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John JS, Christen DR, Flammer KL, Kendall TL, Nazario EC, Richter BP, Gill V, Williams TM. Conservation energetics of beluga whales: using resting and swimming metabolism to understand threats to an endangered population. J Exp Biol 2024; 227:jeb246899. [PMID: 38483264 PMCID: PMC11070638 DOI: 10.1242/jeb.246899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 01/24/2024] [Indexed: 05/08/2024]
Abstract
The balance between energetic costs and acquisition in free-ranging species is essential for survival, and provides important insights regarding the physiological impact of anthropogenic disturbances on wild animals. For marine mammals such as beluga whales (Delphinapterus leucas), the first step in modeling this bioenergetic balance requires an examination of resting and active metabolic demands. Here, we used open-flow respirometry to measure oxygen consumption during surface rest and submerged swimming by trained beluga whales, and compared these measurements with those of a commonly studied odontocete, the Atlantic bottlenose dolphin (Tursiops truncatus). Both resting metabolic rate (3012±126.0 kJ h-1) and total cost of transport (1.4±0.1 J kg-1 m-1) of beluga whales were consistent with predicted values for moderately sized marine mammals in temperate to cold-water environments, including dolphins measured in the present study. By coupling the rate of oxygen consumption during submerged swimming with locomotor metrics from animal-borne accelerometer tags, we developed predictive relationships for assessing energetic costs from swim speed, stroke rate and partial dynamic acceleration. Combining these energetic data with calculated aerobic dive limits for beluga whales (8.8 min), we found that high-speed responses to disturbance markedly reduce the whale's capacity for prolonged submergence, pushing the cetaceans to costly anaerobic performances that require prolonged recovery periods. Together, these species-specific energetic measurements for beluga whales provide two important metrics, gait-related locomotor costs and aerobic capacity limits, for identifying relative levels of physiological vulnerability to anthropogenic disturbances that have become increasingly pervasive in their Arctic habitats.
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Affiliation(s)
- Jason S. John
- University of California, Santa Cruz, Department of Ecology and Evolutionary Biology, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | | | | | - Traci L. Kendall
- University of California, Santa Cruz, Department of Ecology and Evolutionary Biology, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Emily C. Nazario
- University of California, Santa Cruz, Department of Ecology and Evolutionary Biology, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Beau P. Richter
- University of California, Santa Cruz, Department of Ecology and Evolutionary Biology, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Verena Gill
- NOAA Fisheries, 222 W. 7th Ave, Anchorage, AK 99501, USA
| | - Terrie M. Williams
- University of California, Santa Cruz, Department of Ecology and Evolutionary Biology, 130 McAllister Way, Santa Cruz, CA 95060, USA
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Williams TM. Racing extinction: Can science act fast enough to save large, endangered mammals? Science 2024; 383:eadn9607. [PMID: 38301002 DOI: 10.1126/science.adn9607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
How far can a polar bear swim? The answer to that one question could have altered the course of the global warming movement and tempered current public distrust in scienceand scientists. As is the case for many large, fierce mammals, many aspects of the basic biology that dictate what polar bears (Ursus maritimus) need to survive in a changing world remain a mystery. We don't know the limitations of the bear's thermoregulatory or swimming capabilities in Arctic waters. Nor do we know whether a terrestrial diet of berries and scavenging is able to sustain a mother bear throughout pregnancy and cub rearing should the continued deterioration of sea ice force them to remain on land. At a time when understanding animal capacities and resiliency in the face of human perturbation is crucial to species survival, science has been unable to keep pace with emerging environmental threats.
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Affiliation(s)
- Terrie M Williams
- Department of Ecology and Evolutionary Biology, University of California-Santa Cruz, CA USA.
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3
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Nalin A, Pardo DAD, Pitter KL, Sim AJ, Ejaz A, Manne A, Wolfe AR, Williams TM, Bazan JG, Miller ED. Outcomes of Moderately Dose Escalated Hypofractionated Chemoradiation for Pancreatic Cancer. Int J Radiat Oncol Biol Phys 2023; 117:e328. [PMID: 37785161 DOI: 10.1016/j.ijrobp.2023.06.2376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) A modestly hypofractionated course of chemoradiation (CRT) consisting of 36 Gy/15 fractions (F) concurrent with gemcitabine used in PREOPANC and phase II trials has become increasingly common for the treatment of borderline resectable (BR) and locally advanced (LA) pancreatic cancer (PC). Achieving an R0 resection remains a key prognostic factor in PC. We tested whether escalating dose beyond standard dosing (SD) of 36-39 Gy/15 F (or 50-54 Gy/25-30 F) would improve R0 resection rates and outcomes while respecting nearby organs at risk. MATERIALS/METHODS This was a retrospective analysis of consecutive patients at our institution from 2012-2022 with BR/LA PC treated with moderate dose escalated (MDE) (45 Gy/15 F, N = 45) or SD (36-39 Gy/15 F, N = 68 or 50-54 Gy/25-30 F, N = 25) CRT. For MDE, a 5 mm expansion from the duodenum, small bowel, and stomach was created (GI_PRV); PTV was cropped from this structure and prescribed 45 Gy/15 F. The primary endpoint was R0 resection rate with secondary endpoints of cumulative incidence of local progression (LP, recurrence after surgery/imaging progression if no surgery) with death as a competing risk (LP after occurrence of distant metastasis [DM] were still captured), cumulative incidence of DM, and overall survival (OS). Univariable and multivariable competing risks regression analyses were performed to determine the association between baseline covariates and LP. RESULTS We identified 45 patients treated with MDE and 93 treated with SD. Most patients presented with BR disease (55.6% MDE; 54.8% SD) and received neoadjuvant chemotherapy with FOLFIRINOX (98% MDE; 99% SD). All patients in the MDE group and 99% in the SD group received concurrent chemotherapy with gemcitabine used most often (96% MDE; 77% SD). Median follow-up was 17 m (IQR 13-27 m). Surgical resection rates were similar between groups (33.3% MDE vs. 39.8% SD, p = 0.46). Amongst patients that had surgery, R0 resection rates were non-significantly higher in the MDE group (73.3% vs. 47.4%, p = 0.09). Cumulative incidence of LP at 18 m was significantly lower in the MDE group (9.0% vs. 24.8%, p = 0.04). No difference in rates of DM (51.2% MDE vs. 59.6% SD, p = 0.92) or OS at 18 m (53.9% vs. 53.6%, p = 0.89) were observed. On multivariable analysis, MDE (HR = 0.39, p = 0.03) and pancreatic head location (HR = 0.51, p = 0.04) were the only factors independently associated with LP. Rates of grade 2+ gastrointestinal toxicity during CRT (20% MDE vs. 20.9% SD, p = 0.91) and ≤90 days of completing CRT (11.6% MDE vs. 14.8%, p = 0.62) were similar between groups, as were rates of grade 3+ hematologic toxicity (52.3% MDE vs. 41.3% SD, p = 0.23). CONCLUSION In this single institutional study, we found MDE is a simple, safe, and effective strategy associated with improved local control, higher R0 resection rates, and similar toxicity to SD CRT for patients with BR/LA PC. Further prospective data is needed to clarify the role of dose-escalated RT in the management of this lethal malignancy.
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Affiliation(s)
- A Nalin
- Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
| | - D A Diaz Pardo
- Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
| | - K L Pitter
- Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
| | - A J Sim
- Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
| | - A Ejaz
- Division of Surgical Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
| | - A Manne
- Department of Medical Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
| | - A R Wolfe
- Department of Radiation Oncology, The University of Arkansas for Medical Sciences, Little Rock, AR
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - J G Bazan
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - E D Miller
- Department of Radiation Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH
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4
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Han C, Rosa L, Rayn K, Liu A, Wong JYC, Williams TM, Magliari A. Dosimetric Study of Total Marrow and Lymphoid Irradiation on a Ring Gantry-Based Medical Linac with a Two-Layer Multi-Leaf Collimator. Int J Radiat Oncol Biol Phys 2023; 117:e669. [PMID: 37785975 DOI: 10.1016/j.ijrobp.2023.06.2114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) In this study, we aimed to evaluate dosimetric quality of total marrow and lymphoid irradiation (TMLI) plans for a ring gantry-based medical Linac with a two-layer multi-leaf collimator. MATERIALS/METHODS We retrospectively retrieved treatment planning CT images, structure sets, and plan dose for four adult patients, two male and two female, who previously received TMLI treatments on helical tomotherapy (HT) at our institution. TMLI plans were optimized for a ring gantry-based medical Linac with a two-layer multi-leaf collimator (Halcyon, Varian Medical Systems, Inc., Palo Alto, CA). A prescription dose of 12 Gy in 8 fractions was prescribed to the skeletal bones from the skull to mid-thigh, spleen, spinal canal, and lymphoid volume. Five or six isocenters were placed with equal spacing along the patient's longitudinal direction in each TMLI plan with two 6-MV flattening filter-free volumetric modulated arc therapy (VMAT) fields at each isocenter. Isocenter separation ranged from 15 cm to 16.5 cm. Each VMAT field has a field size of 28 cm to 28 cm with the collimator at 90° and a full gantry rotation. The nominal dose rate was 800 MU/minute, and the maximum gantry rotation speed was 24°/sec. Institutional dosimetric constraints were used for optimization including a mean lung dose limit of less than 8 Gy. All the plans were normalized so that 85% the primary planning target volume received the prescription dose. RESULTS The average mean doses to the target volumes ranged from 12.2 to 12.6 Gy in the Halcyon TMLI plans, while they ranged from 12.1 to 12.5 Gy in the HT TMLI plans. Relative to the prescription dose, the average mean dose for normal organs ranged from 21.3% to 56.6% in the Halcyon TMLI plans, while it ranged from 10.1% to 68.4% in the clinical HT plans. The difference in the average mean dose to normal organs was less than 0.5 Gy except two organs between the Halcyon and HT TMLI plans. The average median dose for normal organs ranged from 18.2% to 48.8% relative to the prescription dose in the Halcyon TMLI plans. The mean lung dose (MLD) in the Halcyon TMLI plans met the institutional limit with an average dose of 6.75±0.42 Gy (range: 6.44 - 7.36 Gy), while the average MLD was 6.54±0.77 Gy (range: 6.24 - 7.22 Gy) in the HT plans (p-value = 0.71 in the paired t-test). The average total monitor unit in the Halcyon TMLI plans was 4,425±906 MU (range: 3,470 - 5,575 MU) with an average beam-on time of 5.1±1.3 minutes (range: 4.1 - 7.0 minutes), which excludes isocenter setup time, while the average beam-on time was 22.2±3.2 minutes (range: 19.6 - 26.1 minutes) with the HT plans. CONCLUSION Halcyon TMLI plans met our institutional dosimetric constraints with adequate normal organ sparing and target dose coverage. The beam-on time with the Halcyon plans was significantly shorter than that with the HT plans, which could lead to shorter treatment time and increased patient comfort. This study showed the feasibility of TMLI treatments on the Halcyon machine. The same method could be used for total body irradiation on Halcyon.
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Affiliation(s)
- C Han
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - L Rosa
- Varian Medical Systems Inc, Palo Alto, CA
| | - K Rayn
- Varian Medical Systems Inc, Palo Alto, CA
| | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - J Y C Wong
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - A Magliari
- Varian Medical Systems Inc, Palo Alto, CA
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Kim JH, Liu B, Liu A, Williams TM. Hippocampal Sparing Whole Brain Radiation Therapy: 2 Arc Coplanar and 4 Arc Noncoplanar Planning Comparison. Int J Radiat Oncol Biol Phys 2023; 117:e679. [PMID: 37786000 DOI: 10.1016/j.ijrobp.2023.06.2138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Whole brain radiation therapy (WBRT) has been shown to provide palliation but with negative neurocognitive effects associated with radiation-induced damage to the hippocampus. Sparing of the hippocampus has been shown to reduce the risk of neurocognitive deficit. Hippocampal sparing WBRT plan optimization is commonly done using 2 arc coplanar technique. The purpose of this work is to show that 4 arc noncoplanar plans will improve hippocampal sparing without compromising PTV coverage. MATERIALS/METHODS Retrospective WBRT with hippocampal sparing using 2 arc coplanar and 4 arc noncoplanar VMAT technique were done on 10 patients previously treated for intracranial lesions. CT and MRI fused images were used to delineate the whole brain and hippocampus. Strictly following RTOG 0933 atlas guidelines, the hippocampus was manually delineated by a single Radiation Oncologist. Plans with prescription dose of 30 Gy in 10 fractions were generated using the 2 techniques. The 4 arc noncoplanar plan included 2 partial field arcs with couch angle at 90 degrees and 2 coplanar arcs. The 2 noncoplanar partial arcs consisted of a clockwise arc and a counterclockwise arc with gantry angles between 5 and 179 degrees. Lens were kept to < 7 Gy and pituitary gland to < 30 Gy. Dosimetric parameters from both techniques were compared by paired t-test. RESULTS Radiation dose to the hippocampus was significantly reduced using 4 arc noncoplanar plan when compared to 2 arc coplanar plan. While hippocampus D100% were similar (7.25 Gy vs 7.32 Gy, p = 0.557), the mean dose (9.46 Gy vs 9.87 Gy, p = 0.003) and D0.03cc (12.48 Gy vs 12.94 Gy, p < 0.001) were significantly reduced with 4 arc noncoplanar plans. Whole brain PTV coverage remained at V100% = 95% for both techniques. However, the 4 arc noncoplanar plans showed significantly improved D2% (32.56 Gy vs 32.97 Gy, P = 0.003), D98% (28.11 Gy vs 27.91 Gy, P = 0.01), and homogeneity index (0.141 vs 0.159, P < 0.001). CONCLUSION The 4 arc noncoplanar plans improved hippocampal sparing without compromising PTV coverage or compromise to other nearby organs at risk.
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Affiliation(s)
| | | | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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Yang L, Miller ED, Shakya R, Na R, Hu A, Packard R, Williams TM. Investigation of ATR Inhibitor VX970 as a Radiosensitizer in Colorectal Cancer Cells. Int J Radiat Oncol Biol Phys 2023; 117:e271-e272. [PMID: 37785025 DOI: 10.1016/j.ijrobp.2023.06.1239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Colorectal cancer (CRC) is the second leading cause of combined cancer-related mortality in males and females in the U.S. Traditional treatment of locally advanced rectal cancer consists of neoadjuvant chemoradiation followed by surgery and adjuvant chemotherapy. Emerging data suggests that higher response rates can be achieved with total neoadjuvant therapy (TNT) where delivery of all chemotherapy and radiation therapy (RT) occurs prior to surgery. In addition, for patients with a complete response to TNT, non-operative management (NOM) can be considered. However, despite the use of TNT, pathologic complete response rates remain below 40% and NOM is only achieved in approximately 50% of rectal cancer patients. A strong need remains for more active anti-cancer therapies in rectal cancer to both reduce pelvic recurrence and facilitate NOM. Here, we tested the hypothesis that inhibition of the ataxia telangiectasia and Rad3-related protein kinase (ATR), a critical regulator of cellular DNA damage response, could increase the sensitivity of CRC to RT. MATERIALS/METHODS VX970, a highly potent and selective ATR inhibitor, was investigated as a radiosensitizer in SW48 and LoVo CRC cell models. In vitro, IC50 of VX970 was assessed by alamarBlue cytotoxicity assay, while radiosensitivity was revealed by radiation clonogenic assays (0, 2, 4, 6, 8 Gy). ATR activity was determined by p-Chk1 using immunoblotting, and cell cycle distribution was analyzed by propidium iodide flow cytometry. CRC xenografts were generated using both LoVo and SW48 cells injected in the left flanks of athymic nude mice to explore the radiosensitizing effects of VX970 in vivo. Tumors were allowed to grow to 100-150 mm3, and the mice were randomized into multiple groups [vehicle alone, RT alone (10 Gy/5 fractions), VX970 alone, and VX970+RT]. Mouse weights and tumor size were measured three times weekly. Comparison of treatment groups was performed using the log-rank test with P<0.05 considered significant. RESULTS The IC50 concentrations of VX970 on SW48 and LoVo cells were about 500 and 100 nM, respectively. VX970 at doses of 3 nM did not alter the viability of CRC cells, but significantly sensitized CRC cells to radiotherapy (P<0.05), with DER of 1.43 and 1.59, respectively, in SW48 and LoVo cells. VX970 efficiently attenuated p-Chk1 expression and significantly abrogated radiation induced G2/M cell cycle arrest (P<0.05). In addition, VX970 in combination with radiotherapy significantly prolonged tumor growth delay of CRC xenografts compared to radiation alone (P<0.05), with minimal toxicity observed. CONCLUSION Inhibition of the ATR-Chk1 pathway by targeting ATR kinase with VX970 sensitizes CRC to radiotherapy in vitro and in vivo. Our findings support that ATR inhibition by VX970 is a promising new approach to improve the therapeutic ratio of radiotherapy for patients with CRC and warrants further clinical testing.
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Affiliation(s)
- L Yang
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - E D Miller
- Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - R Shakya
- Target Validation Shared Resource, The Ohio State University, Columbus, OH
| | - R Na
- Target Validation Shared Resource, The Ohio State University, Columbus, OH
| | - A Hu
- The Ohio State University Wexner Medical Center, Columbus, OH
| | - R Packard
- The Ohio State University Wexner Medical Center, Columbus, OH
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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7
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Eustace NJ, Sebastian N, Webb A, Denko N, Shilo K, Robb R, Williams TM. Prognostic Value of Hypoxia Gene Expression Signature in Early-Stage Non-Small Cell Lung Cancer Patients Treated with Stereotactic Body Radiation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:e17-e18. [PMID: 37784778 DOI: 10.1016/j.ijrobp.2023.06.685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic body radiation therapy (SBRT) is an effective alternative to surgery in the treatment of early-stage non-small cell lung cancer (NSCLC). However, disease recurrence occurs in approximately 20-30% of patients. Hypoxia is a well-known factor promoting solid tumor progression, radiation resistance, and immune evasion. In this study, we utilize a previously published hypoxia gene expression signature (Buffa) and measure its association with clinical outcomes in patients with NSCLC treated with SBRT. MATERIALS/METHODS Our study focused on patients with localized, node-negative NSCLC treated with SBRT, and we identified 92 patients treated at our institution between 2008 and 2018 with available gene expression data. Total RNA from formalin-fixed paraffin-embedded archival biopsy specimens (pre-therapy) was isolated and mRNA expression was analyzed using an assay for human samples. For each gene in the Buffa signature, the top 50% of mRNA abundance values were given a score of +1, and the bottom 50% were given a score of -1 to generate a tumor hypoxia score. High scores suggest a hypoxic tumor and low scores imply normoxia. Kaplan-Meier curves were used to assess overall survival, disease-free survival, local recurrence, regional nodal recurrence, and distant recurrence. Cox proportional hazards were performed to account for confounding due to age, T stage, ECOG performance status, biologically effective dose, patient sex, and histology (squamous vs non-squamous). RESULTS The patient's gene expression data were dichotomized based on their median hypoxia score (Table 1). Median follow-up was 23.9 months (95% CI 20.6 - 26.6). A high hypoxia score was associated with squamous histology (p = 0.003). On univariate analysis, a high hypoxia score was significantly associated with local recurrence (hazard ratio [HR] = 5.63; 95% CI 1.03 - 30.78; p = 0.046) and distant recurrence (HR = 1.85; 95% CI 1.14 - 3.02; p = 0.013). There was no significant difference in overall survival (HR = 1.93; 95% CI 0.98 - 3.82; p = 0.058), disease-free survival (HR = 2.13; 95% CI 0.93 - 4.89; p = 0.074), or regional nodal recurrence (HR = 1.45; 95% CI 0.41 - 5.14; p = 0.57). On multivariate analysis, a high hypoxia score was associated with worse overall survival (HR = 2.73; 95% CI 1.23 - 6.07; p = 0.014), local recurrence (HR = 12.85; 95% CI 1.08 - 152.49; p = 0.043) and distant recurrence (HR = 1.91; 95% CI 1.13 - 3.22; p = 0.016). CONCLUSION Our findings demonstrate that a hypoxia gene signature is significantly associated with worse survival and increased local and distant recurrence after SBRT for localized NSCLC. This hypoxia signature may be useful in prognostication, selecting patients for surgery versus radiation, or selecting patients for treatment intensification with radiation or other systemic agents, and should be prospectively validated.
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Affiliation(s)
- N J Eustace
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - N Sebastian
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, OH
| | - A Webb
- Department of Biostatistics, The Ohio State University Wexner Medical Center, Columbus, OH
| | - N Denko
- Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - K Shilo
- Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - R Robb
- Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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8
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Qiu L, Chen Y, Williams TM, Amini A, Sampath S, Glaser SM, Chen YJ, Liu L, Leung D, Liu A, McGee HM. Evaluation of 68Ga-Fibroblast Activation Protein Inhibitor vs. 18F-FDG as a Novel Radiotracer for Biologically Guided Radiation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:e251. [PMID: 37784976 DOI: 10.1016/j.ijrobp.2023.06.1193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Real-time biology guided radiation therapy (BgRT) uses real-time positron emissions from a PET tracer during treatment to guide targeted radiation to cancerous lesions. Fibroblast activation protein alpha (FAP) is highly expressed on cancer-associated fibroblasts in tumors with low expression in normal tissues. While 18F-FDG-PET requires fasting and has background in the liver and brain, 68-Gallium labeled FAP inhibitor (FAPI) does not require fasting and has less background uptake. The goal of this study was to investigate the utility of FAPI as a potential universal fiducial for BgRT. We hypothesized that 68Ga-FAPI would be a better radiotracer than 18F-FDG, as assessed by the Normalized Minimal kBq/mL and the Normal Target Signal (NTS), two parameters used to gauge the suitability of BgRT. MATERIALS/METHODS PET-CTs were obtained for 50 patients with pancreatic, liver, lung, head & neck, and cervical cancer using 18F-FDG and 68Ga-FAPI (n = 10 for each). Four DICOM images were obtained per patient (FDG PET + CT, FAPI PET + CT). Radiation oncologists delineated the gross tumor volume (GTV) on PET images. A separate set of auto-contours were generated from the PET using an auto-threshold of 40% maximum SUV for all tumors. A 1 cm expansion was added to the GTV to create a ring around the physician-generated contours and auto-contours. The following parameters were measured: GTV volume, SUV max of GTV, SUV mean of GTV, Normalized Minimal kBq/mL within the GTV, and NTS (= SUV max/Ring SUV mean). Values were compared using paired t-test. For the BgRT product with similar calculations, the required Normalized Minimal kBq/mL is > 5 kBq/mL; the required NTS is > 2.7 for treatment planning and > 2.0 for BgRT delivery. RESULTS The Normalized Minimal kBq/mL for FAPI was > 5 kBq/mL for all tumors and greater for auto-contoured GTVs compared to physician-contoured GTVs. The mean NTS for the auto-contours for all tumor sites was > 2.0. In addition, there was a statistically significant increase in the NTS for FAPI compared to FDG in pancreatic, liver and head & neck cancers. In pancreatic cancer, there was a statistically significant increase in Normalized Minimal kBq/mL for FAPI compared to FDG (26.0 vs 14.2) (p = 0.01) and the SUVmax of FAPI was almost double that of FDG (15.9 vs 8.2) (p = 0.01). FAPI had no background in the liver, but had high background in the uterus, suggesting it may have a role in liver cancer but not cervical cancer. CONCLUSION This is the first study demonstrating the potential superiority of 68Ga-FAPI compared to 18F-FDG as a biologic fiducial for BgRT when treating pancreatic, liver and head & neck cancers, with a similar efficacy for lung cancer. Our results indicate that auto-contoured GTVs generate a higher NTS than physician-contoured GTVs but all are > 2.0. In addition, the Normalized Minimal kBq/mL for auto-contours is > 5 kBq/mL for all tumors. As hypothesized, FAPI-based BgRT is most likely to be successful when treating tumors with significant desmoplastic stroma, such as pancreatic cancer.
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Affiliation(s)
- L Qiu
- Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Y Chen
- Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - A Amini
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S Sampath
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S M Glaser
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - Y J Chen
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - L Liu
- Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - D Leung
- RefleXion Medical, Inc., Hayward, CA
| | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - H M McGee
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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9
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Wong JYC, Liu B, Dandapani SV, Li YR, Glaser SM, Liu J, Chen Q, Qing K, Chen HK, Simpson J, Da Silva A, Leung D, Feghali K, Dorff TB, Liu A, Williams TM. Pilot Study of a Novel Ring Gantry-Based PET/CT Linear Accelerator in Patients with Prostate Cancer Receiving [18F]-DCFPyL for PSMA PET Imaging. Int J Radiat Oncol Biol Phys 2023; 117:e451. [PMID: 37785452 DOI: 10.1016/j.ijrobp.2023.06.1636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The RefleXion X1® system is a hybrid PET imaging-radiotherapy system that uses real-time positron emissions from a PET tracer to deliver biologically guided radiotherapy (BgRT). This study (NCT05470699) evaluated the hypothesis that the X1 PET imaging subsystem would be able to detect [18F]-DCFPyL PSMA PET signal sufficient to generate a deliverable BgRT plan in patients with prostate cancer. MATERIALS/METHODS Patients with prostate cancer scheduled for a diagnostic [18F]-DCFPyL PSMA PET scan as part of standard of care were eligible. Upon completion of the diagnostic PSMA PET scan, images were transferred to the radiotherapy planning system for target identification and contouring. If at least one PET avid tumor lesion was identified, the patient was then scanned on the X1 unit. BgRT planning was performed on each X1 scanned patient. The target lesion volume, activity concentration (AC) and normalized target signal (NTS) were acquired. Successful and deliverable BgRT plans required that the target AC was ≥ 5 kBq/ml and NTS ≥ 2.7. RESULTS Twenty-six patients underwent [18F]-DCFPyL PET scans (13 with rising PSA after surgery or radiotherapy, 6 with known metastases and 7 with newly diagnosed high-risk prostate cancer). Median (range) PSA was 3.40 (0.04-122). In 16 patients a PET avid tumor was identified and contoured for planning (4 lymph nodes, 5 bone, 6 prostate gland, and 1 prostate bed). In 13 patients the target lesion was visualized on the X1 PET scan, while in 3 patients the target lesion was too close to the bladder to be clearly visualized. BgRT planning was feasible and met standard of care published SBRT organ dose constraints in 8 patients (3 prostate gland, 3 bone, 2 lymph nodes). BgRT planning was not feasible in 8 patients due to insufficient AC, low NTS or proximity of the target lesion to the PET avid bladder. The accompanying table compares median (range) target volume, AC and NTS for feasible versus not feasible plans. CONCLUSION This is the first study to investigate the feasibility of using [18F]-DCFPyL PET imaging for BgRT plan generation on the X1 system in patients with prostate cancer. Lesions that are relevant to radiotherapy of prostate cancer can be visualized including lymph node and bone metastases. A dedicated BgRT workflow with PSMA PET imaging on the X1 at 60 minutes post injection will result in higher target AC and will optimize BgRT planning. PET avid lesions < 1 cm or close to the bladder may make BgRT planning challenging. [18F]-DCFPyL-guided BgRT is technically feasible using the RefleXion X1. BgRT using targeted PET radiopharmaceuticals to biologically guide external beam radiotherapy represents a promising new dimension in radiation oncology and warrants further investigation.
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Affiliation(s)
- J Y C Wong
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - B Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S V Dandapani
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - Y R Li
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S M Glaser
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - J Liu
- Clinical Trials Office, City of Hope National Medical Center, Duarte, CA
| | - Q Chen
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - K Qing
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - H K Chen
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - J Simpson
- Clinical Trials Office, City of Hope National Medical Center, Duarte, CA
| | | | - D Leung
- RefleXion Medical, Inc., Hayward, CA
| | - K Feghali
- RefleXion Medical, Inc., Hayward, CA
| | - T B Dorff
- Department of Medical Oncology & Therapeutics Research, City of Hope National Medical Center, Duarte, CA
| | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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Liu B, Chen Q, Qing K, Dandapani SV, Li YR, Glaser SM, Chen HK, Da Silva A, Leung D, Feghali KAA, Simpson J, Liu J, Dorff TB, Liu A, Williams TM, Wong JYC. Dosimetric Plan Evaluation of Biology Guided Radiotherapy Using [18F]-DCFPyL PSMA Radiotracer in Patients with Prostate Cancer. Int J Radiat Oncol Biol Phys 2023; 117:e688. [PMID: 37786022 DOI: 10.1016/j.ijrobp.2023.06.2158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The X1 system represents a cutting-edge solution in radiotherapy delivery, with its capability to perform Biology Guided Radiotherapy (BgRT). The system utilizes real-time positron emission tomography (PET) signal as biological fiducials to provide tracked dose delivery and is initially available for use with [18F]-Fluorodeoxyglucose (FDG). The aim of this research study is to assess the quality of BgRT treatment plans for prostate cancer using patients' PSMA PET images obtained on the X1 system. MATERIALS/METHODS Sixteen patients with at least one PET-avid tumor identified on their whole-body diagnostic PSMA PET scan were selected. These patients were scanned on X1 following their diagnostic scan without additional radiotracer administration. Based on the X1 PET images, a BgRT plan was created for each patient, with the prescription dose determined by the location of treatment sites. The planning objectives of organs-at-risk (OARs) were established in accordance with the 2018 Timmerman guidelines. Target coverage objective was the dose covering 95% (D95%) of the planning target volume (PTV) to be higher than 100%. The following parameters were analyzed: PTV D95%, the minimal dose (Dmin) of gross tumor volume (GTV), plan maximum dose (Dmax), conformity index (CI), gradient index (GI), and maximum point dose (D0.03cc) to the nearest OARs. The X1 BgRT planning system also generated dose volume histogram (DVH) bounds, which model variations in BgRT delivery. The low boundary of GTV Dmin, representing the minimum GTV dose in the worst-case scenario, was recorded. RESULTS BgRT plans were created for all patients, except for one where the target signal was indistinguishable from the bladder. The prescription dose was 2700 cGy or 3000 cGy in 3 fractions for lymph node lesions, 2400 cGy to 3000 cGy in 3 fractions for bone metastasis, and 4500 cGy in 5 fractions for lesions in prostate. All plans met the dose constraints for OARs as per the Timmerman guidelines. The Dmax of all plans was 129.9% ± 6.9% (mean ± standard deviation). The PTV D95% and GTV Dmin were 101.7% ± 1.0% and 111.0% ± 7.6%, respectively. The low boundary of GTV Dmin was 95.9% ± 5.8%. The CI and GI were 1.22 ± 0.11 and 9.40 ± 2.12, respectively. The D0.03cc to nearest OARs was 84.6% ± 25.4%. The estimated treatment time was 699 ± 228 seconds. CONCLUSION This study is a pioneering effort to evaluate the quality of BgRT plans for prostate cancer patients using the [18F]-DCFPyL PSMA radiotracer. Our results showed that all BgRT plans met the planning objectives defined in the Timmerman protocol. BgRT with [18F]-DCFPyL represents a promising treatment modality for patients with prostate cancer. Further research is needed to validate this approach, including a comprehensive assessment of the dosimetric and tracking accuracy through physical measurements.
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Affiliation(s)
- B Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - Q Chen
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - K Qing
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S V Dandapani
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - Y R Li
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S M Glaser
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - H K Chen
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | | | - D Leung
- RefleXion Medical, Inc., Hayward, CA
| | | | - J Simpson
- Clinical Trials Office, City of Hope National Medical Center, Duarte, CA
| | - J Liu
- Clinical Trials Office, City of Hope National Medical Center, Duarte, CA
| | - T B Dorff
- Department of Medical Oncology & Therapeutics Research, City of Hope National Medical Center, Duarte, CA
| | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - J Y C Wong
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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11
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Liu JR, Ladbury CJ, Glaser SM, Chen YJ, Williams TM, Amini A. Patterns of Care for Patients with Locally Advanced Rectal Cancer Treated with Total Neoadjuvant Therapy between 2016-2020: An NCDB Analysis. Int J Radiat Oncol Biol Phys 2023; 117:e317-e318. [PMID: 37785137 DOI: 10.1016/j.ijrobp.2023.06.2353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Treatment for locally advanced rectal cancer (LARC), defined as T3/4 or any T with N+ disease, typically requires multi-modality management consisting of radiation (RT), chemotherapy (CHT), and surgery. Despite emerging evidence that total neoadjuvant therapy (TNT) is the preferred treatment of LARC, it remains unknown what proportion of patients are receiving TNT in the United States. Our objective was to (1) determine the proportion of patients with LARC receiving TNT over time, (2) determine the most common method in which TNT is being delivered, and (3) determine what factors are associated with a lower likelihood of receiving TNT in the United States. MATERIALS/METHODS Retrospective data was obtained from the National Cancer Database (NCDB) for patients diagnosed with rectal cancer between 2016-2020. Patients were excluded if they had M1 disease, T1-2 N0 disease, incomplete staging information, non-adenocarcinoma histology, received RT to a non-rectum site, or received a non-definitive RT dose. Patients were determined to have received TNT if they (1) received RT and multi-agent (MA)-CHT prior to surgery, (2) had an interval of >180 days from the onset of neoadjuvant therapy to surgery if they received long course (LC)-chemoradiation (CRT) (based on 35 days for LC-CRT + 112 days for 8 cycles of MA-CHT + 30 days to surgery), or (3) had an interval of >150 days from the onset of neoadjuvant therapy to surgery if they received short course (SC)-RT (based on 5 days for SC-RT + 112 days for 8 cycles of MA-CHT + 30 days to surgery). Data were analyzed using linear regression, Chi-square test, and binary logistic regression. RESULTS Of the 26,375 patients included, the median age was 60 (range 21-90) years, with the majority of patients being <65 years old (65.6%), male (62.1%), and non-Hispanic white (77.0%). A total of 5,003 (19.0%) patients received TNT, and 21,372 (81.0%) patients received classical combined modality therapy (CMT). The proportion of patients receiving TNT increased significantly over time, from 6.1% in 2016, 9.0% in 2017, 15.3% in 2018, 25.8% in 2019, to 34.6% in 2020 (slope = 7.36, 95% CI 4.58-10.15, R2 = 0.96, p = 0.040). The most common TNT regimen was MA-CHT followed by LC-CRT (73.2% of cases from 2016-2020). The proportion of patients receiving SC-RT as part of TNT significantly increased from 2.8% in 2016, 1.7% in 2017, 4.6% in 2018, 7.3% in 2019, to 13.7% in 2020 (slope = 2.74, 95% CI 0.37-5.11, R2 = 0.82, p = 0.035). On multivariate analysis, factors associated with a lower likelihood of TNT use included age >65 (OR 0.66, 95% CI 0.61-0.71, p<0.001), female gender (OR 0.92, 95% CI 0.86-0.98, p = 0.014), Black race (OR 0.87, 95% CI 0.77-0.98, p = 0.024), and T3 N0 disease (OR 0.60, 95% CI 0.52-0.70, p<0.001). CONCLUSION TNT utilization rates have significantly increased in recent years, from 6.1% in 2016 to 34.6% in 2020. The observed trend appears to be in line with the recent National Comprehensive Cancer Network (NCCN) guidelines recommending TNT as the preferred approach.
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Affiliation(s)
- J R Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - C J Ladbury
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - S M Glaser
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - Y J Chen
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - A Amini
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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12
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Han C, Ketcherside T, Williams TM, Liu A. Reproducibility and Repeatability of Pelvic Radiomics Features with Daily Imaging on a Novel Biology-Guided Radiotherapy Machine Compared to Daily Imaging on Other Radiotherapy Delivery Systems. Int J Radiat Oncol Biol Phys 2023; 117:e670. [PMID: 37785978 DOI: 10.1016/j.ijrobp.2023.06.2115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Radiomics features extracted from computed tomography (CT) images have the potential of being used as imaging biomarkers in diagnostic and prognostic models for prostate cancer. This study aims to evaluate reproducibility and repeatability of radiomics features using daily CT images from a novel biology-guided radiotherapy (BgRT)-capable machine compared to other daily CT imaging modalities from other radiotherapy delivery systems. MATERIALS/METHODS We retrospectively selected thirty male patients treated to the pelvic region at our institution. Among the thirty patients, ten patients were treated on a BgRT-capable machine with daily fan-beam kilovoltage CT (kVCT) scans, ten patients were treated on a conventional Linac with daily cone-beam CT (CBCT) scans, and ten patients were treated on helical tomotherapy with daily megavoltage CT (MVCT) scans. The prostate gland and femoral heads were delineated on planning CT images and on CT images at the first treatment fraction. After all the CT images were resampled to have an identical voxel size, 107 radiomics features were calculated for the prostate and femoral heads on both the planning CT images and daily CT images. Concordance correlation coefficient (CCC) and Pearson's correlation coefficient (r) were calculated to evaluate radiomics feature reproducibility between the planning CT images and pre-treatment CT scans at the first treatment fraction. To evaluate radiomics feature repeatability with kVCT images on the BgRT-capable machine, a total of ten treatment sessions with repeat kVCT scans on the BgRT-capable machine were retrieved and radiomics features were compared between the first and the second kVCT scans. RESULTS For the prostate gland volume, high concordance (CCC > 0.8) was found for 8, 6, and 0 radiomics features with the first-fraction kVCT, CBCT, and MVCT images, respectively, in relation to the planning CT images, while there was strong correlation (r > 0.8) in 38, 22, and 5 radiomics features in the kVCT, CBCT, and MVCT images, respectively, in relation to the planning CT images. For the left and right femoral heads, high concordance (CCC > 0.8) was found in no more than two radiomics features with the kVCT, CBCT, or MVCT images in relation to the planning CT images. Based on repeat kVCT scan data, 97 (90.7%) radiomics features showed high concordance (CCC > 0.8) in repeat kVCT scans with 98 (91.6%) features showing high correlation (Pearson's correlation coefficient > 0.8) for the prostate gland volume. CONCLUSION A small number of radiomics features were found to show strong reproducibility between daily CT images on the first fraction and the planning CT images with the three IGRT CT modalities in this study. On the other hand, our results indicated that strong reproducibility was found with more radiomics features with daily kVCT images from the BgRT-capable machine compared to daily CBCT and MVCT images for the prostate gland. Strong repeatability was also found with most radiomics features in daily kVCT images.
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Affiliation(s)
- C Han
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T Ketcherside
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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13
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Han C, Wong C, Oderinde OM, Watkins WT, Qing K, Liu B, Williams TM, Liu A. Comparison of AI-Based Auto-Segmentation Quality with Different Daily IGRT Imaging Modalities for Adaptive Radiotherapy Treatment Planning. Int J Radiat Oncol Biol Phys 2023; 117:e670. [PMID: 37785979 DOI: 10.1016/j.ijrobp.2023.06.2116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Modern AI-based auto-segmentation tools may be applied on daily computed tomography (CT) images in an image-guided radiotherapy course to facilitate evaluation of anatomical variations and adaptive treatment planning. However, most AI auto-segmentation models are trained with high-quality diagnostic or planning CT image data. This study aims to evaluate and compare auto-segmentation quality by an AI-based auto-segmentation system with different daily CT imaging modalities. MATERIALS/METHODS We retrospectively retrieved daily IGRT images for sixty patients. Among them, twenty patients were treated on helical tomotherapy with daily megavoltage CT (MVCT) scans, twenty patients were treated on conventional Linacs with daily cone-beam CT (CBCT) scans, and twenty patients were treated on a biology-guided radiotherapy (BgRT)-capable machine with daily fan-beam kilovoltage CT (kVCT) scans. With each treatment modality, ten patients received daily CT scans in the pelvic region while the other ten received daily CT scans in the thoracic region. An auto-segmentation system using a convolutional neural network algorithm was trained in-house with historical treatment planning CT and contouring data to generate auto-segmentation models for the pelvic and thoracic regions, respectively. Normal organs were first delineated the auto-segmentation system on the daily CT images and then drawn by an experienced planner. A set of metrics including the dice similarity coefficient (DSC), Jaccard similarity index, and Hausdorff distance were used to evaluate the quality of the auto segmentation results compared with manual contours. RESULTS The auto-segmentation contours on the kVCT images showed higher average DSC compared to those on the MVCT and CBCT images for all the major organs in both the pelvic and thoracic regions including the bladder, rectum, bowel, left and right femurs, esophagus, heart, left and right lung, and spinal cord. With the kVCT images, the average DSC ranged from 0.52±0.22 to 0.996±0.005. In the pelvic region, the largest absolute difference in DSC was observed for the bowel volume with an average DSC of 0.69±0.16, 0.49±0.27, and 0.32±0.25 for the kVCT, MVCT, and CBCT images, respectively (p-value < 0.05 with unpaired t-tests between kVCT and the other two imaging modalities); in the thoracic region, the largest absolute difference in DSC was observed for the esophagus with an average DSC of 0.63±0.16, 0.22±0.08, and 0.15±0.18 for the kVCT, MVCT, and CBCT images, respectively (p-value < 0.05 with unpaired t-tests between kVCT and the other two imaging modalities). Similar results were observed with other metrics. CONCLUSION The AI-based auto segmentation system showed improved agreement with manual contouring when using kVCT images from the BgRT capable machine compared to MVCT or CBCT images. However, manual correction is necessary on auto-segmentation results from all imaging modalities especially for organs with limited contrast from surrounding tissues.
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Affiliation(s)
- C Han
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - C Wong
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - O M Oderinde
- Health Sciences, Purdue University, West Lafayette, IN
| | - W T Watkins
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - K Qing
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - B Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - T M Williams
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
| | - A Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA
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Williams TM. Mother Nature's playground: Sometimes in the wild it is all about fun. Science 2023; 381:adk6636. [PMID: 37733870 DOI: 10.1126/science.adk6636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/23/2023]
Abstract
From surfboard-stealing sea otters to sailboat-chomping killer whales, the summer of 2023 was a landmark year of wild animal antics. Why is wildlife suddenly interacting with humans and their toys in this way? Speculation and headlines have espoused theories about learned behaviors due to enticements with food, increased intrusion, and proximity of humans in wild habitats, as well as aberrant animal responses instigated by oceanic noise or disease-related neurological disorders. However, the most honest answer is, "We don't really know. Maybe the animals are just playing around."
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Affiliation(s)
- Terrie M Williams
- Department of Ecology and Evolutionary Biology, University of California-Santa Cruz, Santa Cruz, CA 95073, USA.
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15
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Kendall-Bar JM, Williams TM, Mukherji R, Lozano DA, Pitman JK, Holser RR, Keates T, Beltran RS, Robinson PW, Crocker DE, Adachi T, Lyamin OI, Vyssotski AL, Costa DP. Brain activity of diving seals reveals short sleep cycles at depth. Science 2023; 380:260-265. [PMID: 37079694 DOI: 10.1126/science.adf0566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
Sleep is a crucial part of the daily activity patterns of mammals. However, in marine species that spend months or entire lifetimes at sea, the location, timing, and duration of sleep may be constrained. To understand how marine mammals satisfy their daily sleep requirements while at sea, we monitored electroencephalographic activity in wild northern elephant seals (Mirounga angustirostris) diving in Monterey Bay, California. Brain-wave patterns showed that seals took short (less than 20 minutes) naps while diving (maximum depth 377 meters; 104 sleeping dives). Linking these patterns to accelerometry and the time-depth profiles of 334 free-ranging seals (514,406 sleeping dives) revealed a North Pacific sleepscape in which seals averaged only 2 hours of sleep per day for 7 months, rivaling the record for the least sleep among all mammals, which is currently held by the African elephant (about 2 hours per day).
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Affiliation(s)
- Jessica M Kendall-Bar
- Scripps Institution of Oceanography, University of California San Diego, San Diego, CA, USA
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Terrie M Williams
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Ritika Mukherji
- Department of Neuroscience, University of Oxford, Oxford, UK
| | - Daniel A Lozano
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
| | | | - Rachel R Holser
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Theresa Keates
- Ocean Sciences Department, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Roxanne S Beltran
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Patrick W Robinson
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Daniel E Crocker
- Department of Biology, Sonoma State University, Rohnert Park, CA, USA
| | - Taiki Adachi
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Oleg I Lyamin
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA, USA
- A.N. Severtsov Institute of Ecology and Evolution, Moscow, Russia
| | - Alexei L Vyssotski
- Institute of Neuroinformatics, University of Zurich and Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Daniel P Costa
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, USA
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, CA, USA
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16
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Barnewall RJ, Marsh IB, Williams TM, Cusack PMV, Sales N, Galea F, Szentirmay AN, Quinn JC. Efficiency-corrected PCR quantification for identification of prevalence and load of respiratory disease-causing agents in feedlot cattle. Aust Vet J 2022; 100:539-549. [PMID: 36328540 PMCID: PMC9804408 DOI: 10.1111/avj.13200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/10/2022] [Accepted: 07/27/2022] [Indexed: 01/05/2023]
Abstract
Bovine respiratory disease (BRD) is the most prevalent disease in feedlot cattle worldwide with Bovine alphaherpesvirus 1 (BoAHV1), Histophilus somni, Mannheimia haemolytica, Mycoplasma bovis, Pasteurella multocida and Trueperella pyogenes accepted to be common etiological agents associated with BRD. Although these agents are common in the upper and lower airways in clinical BRD cases, some also exist as normal flora suggesting their presence in the upper airways alone is not necessarily informative with respect to disease status or risk. To determine the relationship between presence, load and disease status, we investigated the relationship between load in the upper airways at induction and active BRD cases in feedlot cattle using efficiency-corrected PCR quantification. By this approach, we were able to accurately determine the prevalence and load of the key BRD agents in the upper respiratory tract showing that cattle in the hospital pen had a higher prevalence, and load, of these agents both singly and in combination compared to cattle sampled at feedlot induction. A combination of agents was the most accurate indicator of BRD risk with cattle with four or more agents detected in the upper airway more likely to be undergoing treatment for BRD than non-BRD ailments. In addition, M. bovis was rarely detected at feedlot induction but was identified at high prevalence in cattle in the hospital pen. These findings present a potential new technological approach for the investigation, analysis and identification of BRD-associated viral and bacterial agents for Australian feedlot systems as well as for BRD disease management and treatment.
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Affiliation(s)
- RJ Barnewall
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt UniversityLocked Bag 588Wagga WaggaNew South Wales2678Australia,Gulbali Institute for Agriculture, Water and the EnvironmentWagga WaggaNew South Wales2678Australia
| | - IB Marsh
- NSW DPI, Elizabeth Macarthur Agricultural InstitutePMB 4008NarellanNew South Wales2567Australia
| | - TM Williams
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt UniversityLocked Bag 588Wagga WaggaNew South Wales2678Australia,Gulbali Institute for Agriculture, Water and the EnvironmentWagga WaggaNew South Wales2678Australia,Present address:
School of Health, Medical and Applied Sciences, Central Queensland University554‐700 Yaamba Road, Norman GardensRockhamptonQueensland4701Australia
| | - PMV Cusack
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt UniversityLocked Bag 588Wagga WaggaNew South Wales2678Australia,Australian Livestock Production ServicesCowraNew South Wales2794Australia
| | - N Sales
- NSW DPI, Elizabeth Macarthur Agricultural InstitutePMB 4008NarellanNew South Wales2567Australia
| | - F Galea
- NSW DPI, Elizabeth Macarthur Agricultural InstitutePMB 4008NarellanNew South Wales2567Australia
| | - AN Szentirmay
- Gene Target Solutions Pty Ltd, Unit 3CBuilding 4, 256B New Line RoadDuralNew South Wales2158Australia
| | - JC Quinn
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt UniversityLocked Bag 588Wagga WaggaNew South Wales2678Australia,Gulbali Institute for Agriculture, Water and the EnvironmentWagga WaggaNew South Wales2678Australia
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17
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Abstract
Modification of cerebral vasculature helps to cushion the brains of whales and dolphins against injury.
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Affiliation(s)
- Terrie M Williams
- Department of Ecology and Evolutionary Biology, University of California - Santa Cruz, Santa Cruz, CA, USA
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18
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Harrison JF, Biewener A, Bernhardt JR, Burger JR, Brown JH, Coto ZN, Duell ME, Lynch M, Moffett ER, Norin T, Pettersen AK, Smith FA, Somjee U, Traniello JFA, Williams TM. White Paper: An Integrated Perspective on the Causes of Hypometric Metabolic Scaling in Animals. Integr Comp Biol 2022; 62:icac136. [PMID: 35933126 PMCID: PMC9724154 DOI: 10.1093/icb/icac136] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 04/16/2022] [Accepted: 05/19/2022] [Indexed: 11/15/2022] Open
Abstract
Larger animals studied during ontogeny, across populations, or across species, usually have lower mass-specific metabolic rates than smaller animals (hypometric scaling). This pattern is usually observed regardless of physiological state (e.g. basal, resting, field, maximally-active). The scaling of metabolism is usually highly correlated with the scaling of many life history traits, behaviors, physiological variables, and cellular/molecular properties, making determination of the causation of this pattern challenging. For across-species comparisons of resting and locomoting animals (but less so for across populations or during ontogeny), the mechanisms at the physiological and cellular level are becoming clear. Lower mass-specific metabolic rates of larger species at rest are due to a) lower contents of expensive tissues (brains, liver, kidneys), and b) slower ion leak across membranes at least partially due to membrane composition, with lower ion pump ATPase activities. Lower mass-specific costs of larger species during locomotion are due to lower costs for lower-frequency muscle activity, with slower myosin and Ca++ ATPase activities, and likely more elastic energy storage. The evolutionary explanation(s) for hypometric scaling remain(s) highly controversial. One subset of evolutionary hypotheses relies on constraints on larger animals due to changes in geometry with size; for example, lower surface-to-volume ratios of exchange surfaces may constrain nutrient or heat exchange, or lower cross-sectional areas of muscles and tendons relative to body mass ratios would make larger animals more fragile without compensation. Another subset of hypotheses suggests that hypometric scaling arises from biotic interactions and correlated selection, with larger animals experiencing less selection for mass-specific growth or neurolocomotor performance. A additional third type of explanation comes from population genetics. Larger animals with their lower effective population sizes and subsequent less effective selection relative to drift may have more deleterious mutations, reducing maximal performance and metabolic rates. Resolving the evolutionary explanation for the hypometric scaling of metabolism and associated variables is a major challenge for organismal and evolutionary biology. To aid progress, we identify some variation in terminology use that has impeded cross-field conversations on scaling. We also suggest that promising directions for the field to move forward include: 1) studies examining the linkages between ontogenetic, population-level, and cross-species allometries, 2) studies linking scaling to ecological or phylogenetic context, 3) studies that consider multiple, possibly interacting hypotheses, and 4) obtaining better field data for metabolic rates and the life history correlates of metabolic rate such as lifespan, growth rate and reproduction.
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Affiliation(s)
- Jon F Harrison
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA
| | - Andrew Biewener
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Joanna R Bernhardt
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Yale Institute for Biospheric Studies, New Haven, CT 06520, USA
| | - Joseph R Burger
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - James H Brown
- Center for Evolutionary and Theoretical Immunology, The University of New Mexico, Albuquerque, NM 87131, USA
| | - Zach N Coto
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Meghan E Duell
- Department of Biology, The University of Western Ontario, London, ON N6A 3K7, Canada
| | - Michael Lynch
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ 85281, USA
| | - Emma R Moffett
- Department of Ecology and Evolution, University of California, Irvine, CA 92697, USA
| | - Tommy Norin
- DTU Aqua | National Institute of Aquatic Resources, Technical University of Denmark, Anker Engelunds Vej 1 Bygning 101A, 2800 Kgs. Lyngby, Denmark
| | - Amanda K Pettersen
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Felisa A Smith
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Ummat Somjee
- Smithsonian Tropical Research Institute, Panama City, Panama
| | | | - Terrie M Williams
- Division of Physical and Biological Sciences, University of California, Santa Cruz, CA 95064, USA
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19
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Williams TM, Blackwell SB, Tervo O, Garde E, Sinding MS, Richter B, Heide‐Jørgensen MP. Physiological responses of narwhals to anthropogenic noise: A case study with seismic airguns and vessel traffic in the Arctic. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Terrie M. Williams
- Coastal Biology Building‐ Department of Ecology and Evolutionary Biology, 130 McAllister Way University of California‐ Santa Cruz CA
| | | | - Outi Tervo
- Greenland Institute of Natural Resources Copenhagen K Denmark
| | - Eva Garde
- Greenland Institute of Natural Resources Copenhagen K Denmark
| | | | - Beau Richter
- Coastal Biology Building‐ Department of Ecology and Evolutionary Biology, 130 McAllister Way University of California‐ Santa Cruz CA
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20
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Abstract
Reinvasion of the oceans beginning 10-60 million years ago by ancient mammals instigated one of the most remarkable metabolic transitions across evolutionary time. A consequence of marine living, especially in colder waters, has been a 1.4 to 2.9-fold increase in resting metabolic rate (RMR) for otters, pinnipeds and cetaceans over predicted levels for terrestrial mammals of similar body mass. Notably, the greatest metabolic elevation occurred in the smallest marine mammals, suggesting an underlying thermal causative mechanism. Superimposed on these resting costs are the metabolic demands of locomotion. Collectively termed the field metabolic rate, such active costs consistently approach three times the resting rates of individuals regardless of locomotor style, species, foraging patterns, habitat or geographic location. In wild non-reproducing mammals, the FMR/RMR ratio averages 2.6-2.8 for both terrestrial and marine species, with the latter group maintaining larger absolute daily metabolic rates supported by comparatively higher food ingestion rates. Interestingly, the limit for habitual (multi-day), sustained maximal energy expenditure in human endurance athletes averages < 3.0 times resting metabolic levels, with a notable exception in Tour de France cyclists. Importantly, both athletes and wild mammals seem similarly constrained; that is, by the ability to process enough calories in a day to support exceptional metabolic performance.
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Affiliation(s)
- Terrie M Williams
- Department of Ecology and Evolutionary Biology, University of California- Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95064
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21
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Ackermans NL, Varghese M, Williams TM, Grimaldi N, Selmanovic E, Alipour A, Balchandani P, Reidenberg JS, Hof PR. Evidence of traumatic brain injury in headbutting bovids. Acta Neuropathol 2022; 144:5-26. [PMID: 35579705 PMCID: PMC9217783 DOI: 10.1007/s00401-022-02427-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 04/20/2022] [Accepted: 04/26/2022] [Indexed: 12/24/2022]
Abstract
Traumatic brain injury (TBI) is a leading cause of neurologic impairment and death that remains poorly understood. Rodent models have yet to produce clinical therapies, and the exploration of larger and more diverse models remains relatively scarce. We investigated the potential for brain injury after headbutting in two combative bovid species by assessing neuromorphology and neuropathology through immunohistochemistry and stereological quantification. Postmortem brains of muskoxen (Ovibos moschatus, n = 3) and bighorn sheep (Ovis canadensis, n = 4) were analyzed by high-resolution MRI and processed histologically for evidence of TBI. Exploratory histological protocols investigated potential abnormalities in neurons, microglia, and astrocytes in the prefrontal and parietal cortex. Phosphorylated tau protein, a TBI biomarker found in the cerebrospinal fluid and in neurodegenerative lesions, was used to detect possible cellular consequences of chronic or acute TBI. MRI revealed no abnormal neuropathological changes; however, high amounts of tau-immunoreactive neuritic thread clusters, neurites, and neurons were concentrated in the superficial layers of the neocortex, preferentially at the bottom of the sulci in the muskoxen and occasionally around blood vessels. Tau-immunoreactive lesions were rare in the bighorn sheep. Additionally, microglia and astrocytes showed no grouping around tau-immunoreactive cells in either species. Our preliminary findings indicate that muskoxen and possibly other headbutting bovids suffer from chronic or acute brain trauma and that the males’ thicker skulls may protect them to a certain extent.
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22
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Nisi AC, Suraci JP, Ranc N, Frank LG, Oriol-Cotterill A, Ekwanga S, Williams TM, Wilmers CC. Temporal scale of habitat selection for large carnivores: Balancing energetics, risk and finding prey. J Anim Ecol 2021; 91:182-195. [PMID: 34668571 PMCID: PMC9298125 DOI: 10.1111/1365-2656.13613] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 09/19/2021] [Indexed: 11/29/2022]
Abstract
When navigating heterogeneous landscapes, large carnivores must balance trade-offs between multiple goals, including minimizing energetic expenditure, maintaining access to hunting opportunities and avoiding potential risk from humans. The relative importance of these goals in driving carnivore movement likely changes across temporal scales, but our understanding of these dynamics remains limited. Here we quantified how drivers of movement and habitat selection changed with temporal grain for two large carnivore species living in human-dominated landscapes, providing insights into commonalities in carnivore movement strategies across regions. We used high-resolution GPS collar data and integrated step selection analyses to model movement and habitat selection for African lions Panthera leo in Laikipia, Kenya and pumas Puma concolor in the Santa Cruz Mountains of California across eight temporal grains, ranging from 5 min to 12 hr. Analyses considered landscape covariates that are related to energetics, resource acquisition and anthropogenic risk. For both species, topographic slope, which strongly influences energetic expenditure, drove habitat selection and movement patterns over fine temporal grains but was less important at longer temporal grains. In contrast, avoiding anthropogenic risk during the day, when risk was highest, was consistently important across grains, but the degree to which carnivores relaxed this avoidance at night was strongest for longer term movements. Lions and pumas modified their movement behaviour differently in response to anthropogenic features: lions sped up while near humans at fine temporal grains, while pumas slowed down in more developed areas at coarse temporal grains. Finally, pumas experienced a trade-off between energetically efficient movement and avoiding anthropogenic risk. Temporal grain is an important methodological consideration in habitat selection analyses, as drivers of both movement and habitat selection changed across temporal grain. Additionally, grain-dependent patterns can reflect meaningful behavioural processes, including how fitness-relevant goals influence behaviour over different periods of time. In applying multi-scale analysis to fine-resolution data, we showed that two large carnivore species in very different human-dominated landscapes balanced competing energetic and safety demands in largely similar ways. These commonalities suggest general strategies of landscape use across large carnivore species.
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Affiliation(s)
- Anna C Nisi
- Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA, USA
| | - Justin P Suraci
- Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA, USA.,Conservation Science Partners, Truckee, CA, USA
| | - Nathan Ranc
- Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA, USA
| | - Laurence G Frank
- Living with Lions, Mpala Research Centre, Nanyuki, Kenya.,Museum of Vertebrate Zoology, University of California, Berkeley, CA, USA
| | - Alayne Oriol-Cotterill
- Wildlife Conservation Research Unit, Zoology Department, Oxford University, Abingdon, UK.,Lion Landscapes, Teignmouth, UK
| | - Steven Ekwanga
- Living with Lions, Mpala Research Centre, Nanyuki, Kenya
| | - Terrie M Williams
- Ecology and Evolutionary Biology Department, University of California, Santa Cruz, CA, USA
| | - Christopher C Wilmers
- Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA, USA
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23
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Ackermans NL, Varghese M, Wicinski B, Torres J, De Gasperi R, Pryor D, Elder GA, Gama Sosa MA, Reidenberg JS, Williams TM, Hof PR. Unconventional animal models for traumatic brain injury and chronic traumatic encephalopathy. J Neurosci Res 2021; 99:2463-2477. [PMID: 34255876 PMCID: PMC8596618 DOI: 10.1002/jnr.24920] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/09/2021] [Accepted: 06/24/2021] [Indexed: 12/11/2022]
Abstract
Traumatic brain injury (TBI) is one of the main causes of death worldwide. It is a complex injury that influences cellular physiology, causes neuronal cell death, and affects molecular pathways in the brain. This in turn can result in sensory, motor, and behavioral alterations that deeply impact the quality of life. Repetitive mild TBI can progress into chronic traumatic encephalopathy (CTE), a neurodegenerative condition linked to severe behavioral changes. While current animal models of TBI and CTE such as rodents, are useful to explore affected pathways, clinical findings therein have rarely translated into clinical applications, possibly because of the many morphofunctional differences between the model animals and humans. It is therefore important to complement these studies with alternative animal models that may better replicate the individuality of human TBI. Comparative studies in animals with naturally evolved brain protection such as bighorn sheep, woodpeckers, and whales, may provide preventive applications in humans. The advantages of an in-depth study of these unconventional animals are threefold. First, to increase knowledge of the often-understudied species in question; second, to improve common animal models based on the study of their extreme counterparts; and finally, to tap into a source of biological inspiration for comparative studies and translational applications in humans.
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Affiliation(s)
- Nicole L Ackermans
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Merina Varghese
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Bridget Wicinski
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Joshua Torres
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Rita De Gasperi
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- General Medical Research Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY, USA
| | - Dylan Pryor
- General Medical Research Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY, USA
| | - Gregory A Elder
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Neurology Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY, USA
| | - Miguel A Gama Sosa
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- General Medical Research Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY, USA
| | - Joy S Reidenberg
- Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Terrie M Williams
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, USA
| | - Patrick R Hof
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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24
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John JS, Thometz NM, Boerner K, Denum L, Kendall TL, Richter BP, Gaspard JC, Williams TM. Metabolic trade-offs in tropical and subtropical marine mammals: unique maintenance and locomotion costs in West Indian manatees and Hawaiian monk seals. J Exp Biol 2021; 224:271210. [PMID: 34357378 PMCID: PMC8353161 DOI: 10.1242/jeb.237628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 06/09/2021] [Indexed: 11/20/2022]
Abstract
Unlike the majority of marine mammal species, Hawaiian monk seals (Neomonachus schauinslandi) and West Indian manatees (Trichechus manatus latirostris) reside exclusively in tropical or subtropical waters. Although potentially providing an energetic benefit through reduced maintenance and thermal costs, little is known about the cascading effects that may alter energy expenditure during activity, dive responses and overall energy budgets for these warm-water species. To examine this, we used open-flow respirometry to measure the energy expended during resting and swimming in both species. We found that the average resting metabolic rates (RMRs) for both the adult monk seal (753.8±26.1 kJ h-1, mean±s.e.m.) and manatees (887.7±19.5 kJ h-1) were lower than predicted for cold-water marine mammal species of similar body mass. Despite these relatively low RMRs, both total cost per stroke and total cost of transport (COTTOT) during submerged swimming were similar to predictions for comparably sized marine mammals (adult monk seal: cost per stroke=5.0±0.2 J kg-1 stroke-1, COTTOT=1.7±0.1 J kg-1 m-1; manatees: cost per stroke=2.0±0.4 J kg-1 stroke-1, COTTOT=0.87±0.17 J kg-1 m-1). These lower maintenance costs result in less variability in adjustable metabolic costs that occur during submergence for warm-water species. However, these reduced maintenance costs do not appear to confer an advantage in overall energetic costs during activity, potentially limiting the capacity of warm-water species to respond to anthropogenic or environmental threats that require increased energy expenditure.
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Affiliation(s)
- Jason S John
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Nicole M Thometz
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA.,University of San Francisco, 2130 Fulton Street, San Francisco, CA 94117, USA
| | - Katharine Boerner
- Mote Marine Laboratory & Aquarium, 1600 Ken Thompson Pkwy, Sarasota, FL 34236, USA
| | - Laura Denum
- Mote Marine Laboratory & Aquarium, 1600 Ken Thompson Pkwy, Sarasota, FL 34236, USA
| | - Traci L Kendall
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Beau P Richter
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Joseph C Gaspard
- Pittsburgh Zoo & PPG Aquarium, One Wild Place, Pittsburgh, PA 15206, USA
| | - Terrie M Williams
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
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25
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Pagano AM, Williams TM. Physiological consequences of Arctic sea ice loss on large marine carnivores: unique responses by polar bears and narwhals. J Exp Biol 2021; 224:224/Suppl_1/jeb228049. [PMID: 33627459 DOI: 10.1242/jeb.228049] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Rapid environmental changes in the Arctic are threatening the survival of marine species that rely on the predictable presence of the sea ice. Two Arctic marine mammal specialists, the polar bear (Ursus maritimus) and narwhal (Monodon monoceros), appear especially vulnerable to the speed and capriciousness of sea ice deterioration as a consequence of their unique hunting behaviors and diet, as well as their physiological adaptations for slow-aerobic exercise. These intrinsic characteristics limit the ability of these species to respond to extrinsic threats associated with environmental change and increased industrial activity in a warming Arctic. In assessing how sea ice loss may differentially affect polar bears that hunt on the ice surface and narwhals that hunt at extreme depths below, we found that major ice loss translated into elevated locomotor costs that range from 3- to 4-fold greater than expected for both species. For polar bears this instigates an energy imbalance from the combined effects of reduced caloric intake and increased energy expenditure. For narwhals, high locomotor costs during diving increase the risk of ice entrapment due to the unreliability of breathing holes. These species-specific physiological constraints and extreme reliance on the polar sea ice conspire to make these two marine mammal specialists sentinels of climate change within the Arctic marine ecosystem that may foreshadow rapid changes to the marine ecosystem.
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Affiliation(s)
- Anthony M Pagano
- Institute for Conservation Research, San Diego Zoo Global, San Diego, CA 92027, USA
| | - Terrie M Williams
- University of California, Santa Cruz, Department of Ecology and Evolutionary Biology, Santa Cruz, CA 95060, USA
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26
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Williams TM, Davis RW. Physiological resiliency in diving mammals: Insights on hypoxia protection using the Krogh principle to understand COVID-19 symptoms. Comp Biochem Physiol A Mol Integr Physiol 2020; 253:110849. [PMID: 33227435 PMCID: PMC8711794 DOI: 10.1016/j.cbpa.2020.110849] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 11/27/2022]
Abstract
Sequential diving by wild marine mammals results in a lifetime of rapid physiological transitions between lung collapse-reinflation, bradycardia-tachycardia, vasoconstriction-vasodilation, and oxygen store depletion-restoration. The result is a cycle of normoxia and hypoxia in which blood oxygen partial pressures can decline to <20–30 mmHg during a dive, a level considered injurious to oxygen-dependent human tissues (i.e., brain, heart). Safeguards in the form of enhanced on-board oxygen stores, selective oxygen transport, and unique tissue buffering capacities enable marine-adapted mammals to maintain physiological homeostasis and energy metabolism even when breathing and pulmonary gas exchange cease. This stands in stark contrast to the vulnerability of oxygen-sensitive tissues in humans that may undergo irreversible damage within minutes of ischemia and tissue hypoxia. Recently, these differences in protection against hypoxic injury have become evident in the systemic, multi-organ physiological failure during COVID-19 infection in humans. Prolonged recoveries in some patients have led to delays in the return to normal exercise levels and cognitive function even months later. Rather than a single solution to this problem, we find that marine mammals rely on a unique, integrative assemblage of protections to avoid the deleterious impacts of hypoxia on tissues. Built across evolutionary time, these solutions provide a natural template for identifying the potential for tissue damage when oxygen is lacking, and for guiding management decisions to support oxygen-deprived tissues in other mammalian species, including humans, challenged by hypoxia.
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Affiliation(s)
- Terrie M Williams
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, USA.
| | - Randall W Davis
- Department of Marine Biology, Texas A&M University, Galveston, TX, USA
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27
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Chambault P, Tervo OM, Garde E, Hansen RG, Blackwell SB, Williams TM, Dietz R, Albertsen CM, Laidre KL, Nielsen NH, Richard P, Sinding MHS, Schmidt HC, Heide-Jørgensen MP. The impact of rising sea temperatures on an Arctic top predator, the narwhal. Sci Rep 2020; 10:18678. [PMID: 33122802 PMCID: PMC7596713 DOI: 10.1038/s41598-020-75658-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 10/14/2020] [Indexed: 02/04/2023] Open
Abstract
Arctic top predators are expected to be impacted by increasing temperatures associated with climate change, but the relationship between increasing sea temperatures and population dynamics of Arctic cetaceans remains largely unexplored. Narwhals (Monodon monoceros) are considered to be among the most sensitive of Arctic endemic marine mammals to climate change due to their limited prey selection, strict migratory patterns and high site fidelity. In the context of climate change, we assume that the population dynamics of narwhals are partly influenced by changes in environmental conditions, with warm areas of increasing sea temperatures having lower abundance of narwhals. Using a unique large dataset of 144 satellite tracked narwhals, sea surface temperature (SST) data spanning 25 years (1993–2018) and narwhal abundance estimates from 17 localities, we (1) assessed the thermal exposure of this species, (2) investigated the SST trends at the summer foraging grounds, and (3) assessed the relationship between SST and abundance of narwhals. We showed a sharp SST increase in Northwest, Mideast and Southeast Greenland, whereas no change could be detected in the Canadian Arctic Archipelago (CAA) and in the Greenland Sea. The rising sea temperatures were correlated with the smallest narwhal abundance observed in the Mideast and Southeast Greenland (< 2000 individuals), where the mean summer sea temperatures were the highest (6.3 °C) compared to the cold waters of the CAA (0.7 °C) that were associated with the largest narwhal populations (> 40,000 individuals). These results support the hypothesis that warming ocean waters will restrict the habitat range of the narwhal, further suggesting that narwhals from Mideast and Southeast Greenland may be under pressure to abandon their traditional habitats due to ocean warming, and consequently either migrate further North or locally go extinct.
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Affiliation(s)
- P Chambault
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark.
| | - O M Tervo
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark
| | - E Garde
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark
| | - R G Hansen
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark
| | - S B Blackwell
- Greeneridge Sciences, Inc, 5266 Hollister Avenue, Suite 107, Santa Barbara, CA, 93111, USA
| | | | - R Dietz
- Department of Bioscience, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark
| | - C M Albertsen
- DTU Aqua, Technical University of Denmark, 2800, Kgs. Lyngby, DK, Denmark
| | - K L Laidre
- Applied Physics Laboratory, Polar Science Center, University of Washington, Seattle, WA, 98105-6698, USA
| | - N H Nielsen
- Greenland Institute of Natural Resources, Box 570, 3900, Nuuk, Greenland
| | - P Richard
- Fisheries and Oceans Canada, Winnipeg, MB, R3T 2N6, Canada
| | - M H S Sinding
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark.,Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - H C Schmidt
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark
| | - M P Heide-Jørgensen
- Greenland Institute of Natural Resources, Strandgade 91, 1401, Copenhagen, Denmark
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28
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Williams TM, Peter‐Heide Jørgensen M, Pagano AM, Bryce CM. Hunters versus hunted: New perspectives on the energetic costs of survival at the top of the food chain. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13649] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Terrie M. Williams
- Department of Ecology and Evolutionary Biology Coastal Biology Building University of California Santa Cruz Santa Cruz CA USA
| | | | - Anthony M. Pagano
- Institute for Conservation Research San Diego Zoo Global San Diego CA USA
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Wright TJ, Davis RW, Holser RR, Hückstädt LA, Danesi CP, Porter C, Widen SG, Williams TM, Costa DP, Sheffield-Moore M. Changes in Northern Elephant Seal Skeletal Muscle Following Thirty Days of Fasting and Reduced Activity. Front Physiol 2020; 11:564555. [PMID: 33123026 PMCID: PMC7573231 DOI: 10.3389/fphys.2020.564555] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/17/2020] [Indexed: 12/21/2022] Open
Abstract
Northern elephant seals (NES, Mirounga angustirostris) undergo an annual molt during which they spend ∼40 days fasting on land with reduced activity and lose approximately one-quarter of their body mass. Reduced activity and muscle load in stereotypic terrestrial mammalian models results in decreased muscle mass and capacity for force production and aerobic metabolism. However, the majority of lost mass in fasting female NES is from fat while muscle mass is largely preserved. Although muscle mass is preserved, potential changes to the metabolic and contractile capacity are unknown. To assess potential changes in NES skeletal muscle during molt, we collected muscle biopsies from 6 adult female NES before the molt and after ∼30 days at the end of the molt. Skeletal muscle was assessed for respiratory capacity using high resolution respirometry, and RNA was extracted to assess changes in gene expression. Despite a month of reduced activity, fasting, and weight loss, skeletal muscle respiratory capacity was preserved with no change in OXPHOS respiratory capacity. Molt was associated with 162 upregulated genes including those favoring lipid metabolism. We identified 172 downregulated genes including those coding for ribosomal proteins and genes associated with skeletal muscle force transduction and glucose metabolism. Following ∼30 days of molt, NES skeletal muscle metabolic capacity is preserved although mechanotransduction may be compromised. In the absence of exercise stimulus, fasting-induced shifts in muscle metabolism may stimulate pathways associated with preserving the mass and metabolic capacity of slow oxidative muscle.
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Affiliation(s)
- Traver J Wright
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, United States.,Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Randall W Davis
- Department of Marine Biology, Texas A&M University, Galveston, TX, United States
| | - Rachel R Holser
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Luis A Hückstädt
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Christopher P Danesi
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Craig Porter
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
| | - Terrie M Williams
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Daniel P Costa
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Melinda Sheffield-Moore
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, United States.,Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
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30
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Dunford CE, Marks NJ, Wilmers CC, Bryce CM, Nickel B, Wolfe LL, Scantlebury DM, Williams TM. Surviving in steep terrain: a lab-to-field assessment of locomotor costs for wild mountain lions ( Puma concolor). Mov Ecol 2020; 8:34. [PMID: 32782806 PMCID: PMC7414561 DOI: 10.1186/s40462-020-00215-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 06/09/2020] [Indexed: 05/28/2023]
Abstract
BACKGROUND Under current scenarios of climate change and habitat loss, many wild animals, especially large predators, are moving into novel energetically challenging environments. Consequently, changes in terrain associated with such moves may heighten energetic costs and effect the decline of populations in new localities. METHODS To examine locomotor costs of a large carnivorous mammal moving in mountainous habitats, the oxygen consumption of captive pumas (Puma concolor) was measured during treadmill locomotion on level and incline (6.8°) surfaces. These data were used to predict energetic costs of locomotor behaviours of free-ranging pumas equipped with GPS/accelerometer collars in California's Santa Cruz Mountains. RESULTS Incline walking resulted in a 42.0% ± 7.2 SEM increase in the costs of transport compared to level performance. Pumas negotiated steep terrain by traversing across hillsides (mean hill incline 17.2° ± 0.3 SEM; mean path incline 7.3° ± 0.1 SEM). Pumas also walked more slowly up steeper paths, thereby minimizing the energetic impact of vertical terrains. Estimated daily energy expenditure (DEE) based on GPS-derived speeds of free-ranging pumas was 18.3 MJ day- 1 ± 0.2 SEM. Calculations show that a 20 degree increase in mean steepness of the terrain would increase puma DEE by less than 1% as they only spend a small proportion (10%) of their day travelling. They also avoided elevated costs by utilizing slower speeds and shallower path angles. CONCLUSIONS While many factors influence survival in novel habitats, we illustrate the importance of behaviours which reduce locomotor costs when traversing new, energetically challenging environments, and demonstrate that these behaviours are utilised by pumas in the wild.
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Affiliation(s)
- Carolyn E. Dunford
- School of Biological Sciences, Institute of Global Food Security, Queen’s University of Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland
| | - Nikki J. Marks
- School of Biological Sciences, Institute of Global Food Security, Queen’s University of Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland
| | - Christopher C. Wilmers
- Center for Integrated Spatial Research, Environmental Studies Department, University of California- Santa Cruz, Santa Cruz, CA 95064 USA
| | | | - Barry Nickel
- Center for Integrated Spatial Research, Environmental Studies Department, University of California- Santa Cruz, Santa Cruz, CA 95064 USA
| | - Lisa L. Wolfe
- Colorado Division of Parks and Wildlife, Wildlife Health Program, 4330 Laporte Avenue, Fort Collins, CO 80521-2153 USA
| | - D. Michael Scantlebury
- School of Biological Sciences, Institute of Global Food Security, Queen’s University of Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL Northern Ireland
| | - Terrie M. Williams
- Department of Ecology and Evolutionary Biology, Coastal Biology Building, 130 McAllister Way, University of California- Santa Cruz, Santa Cruz, CA 95060 USA
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31
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Heide‐Jørgensen MP, Blackwell SB, Williams TM, Sinding MHS, Skovrind M, Tervo OM, Garde E, Hansen RG, Nielsen NH, Ngô MC, Ditlevsen S. Some like it cold: Temperature-dependent habitat selection by narwhals. Ecol Evol 2020; 10:8073-8090. [PMID: 32788962 PMCID: PMC7417212 DOI: 10.1002/ece3.6464] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 05/11/2020] [Accepted: 05/15/2020] [Indexed: 12/27/2022] Open
Abstract
The narwhal (Monodon monoceros) is a high-Arctic species inhabiting areas that are experiencing increases in sea temperatures, which together with reduction in sea ice are expected to modify the niches of several Arctic marine apex predators. The Scoresby Sound fjord complex in East Greenland is the summer residence for an isolated population of narwhals. The movements of 12 whales instrumented with Fastloc-GPS transmitters were studied during summer in Scoresby Sound and at their offshore winter ground in 2017-2019. An additional four narwhals provided detailed hydrographic profiles on both summer and winter grounds. Data on diving of the whales were obtained from 20 satellite-linked time-depth recorders and 16 Acousonde™ recorders that also provided information on the temperature and depth of buzzes. In summer, the foraging whales targeted depths between 300 and 850 m where the preferred areas visited by the whales had temperatures ranging between 0.6 and 1.5°C (mean = 1.1°C, SD = 0.22). The highest probability of buzzing activity during summer was at a temperature of 0.7°C and at depths > 300 m. The whales targeted similar depths at their offshore winter ground where the temperature was slightly higher (range: 0.7-1.7°C, mean = 1.3°C, SD = 0.29). Both the probability of buzzing events and the spatial distribution of the whales in both seasons demonstrated a preferential selection of cold water. This was particularly pronounced in winter where cold coastal water was selected and warm Atlantic water farther offshore was avoided. It is unknown if the small temperature niche of whales while feeding is because prey is concentrated at these temperature gradients and is easier to capture at low temperatures, or because there are limitations in the thermoregulation of the whales. In any case, the small niche requirements together with their strong site fidelity emphasize the sensitivity of narwhals to changes in the thermal characteristics of their habitats.
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Affiliation(s)
| | | | - Terrie M. Williams
- Center for Ocean Health – Long Marine LaboratoryUniversity of California‐Santa CruzSanta CruzCAUSA
| | - Mikkel Holger S. Sinding
- Greenland Institute of Natural ResourcesCopenhagenDenmark
- Smurfit Institute of GeneticsTrinity College DublinDublinIreland
| | | | - Outi M. Tervo
- Greenland Institute of Natural ResourcesCopenhagenDenmark
| | - Eva Garde
- Greenland Institute of Natural ResourcesCopenhagenDenmark
| | | | | | - Mạnh Cường Ngô
- Greenland Institute of Natural ResourcesCopenhagenDenmark
| | - Susanne Ditlevsen
- Data Science LaboratoryDepartment of Mathematical SciencesUniversity of CopenhagenCopenhagenDenmark
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32
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Sebastian NT, Tan Y, Miller ED, Williams TM, Diaz DA. Surgery with and without adjuvant radiotherapy is associated with similar survival in T4 colon cancer. Colorectal Dis 2020; 22:779-789. [PMID: 31910314 DOI: 10.1111/codi.14953] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 11/29/2019] [Indexed: 01/11/2023]
Abstract
AIM There is little evidence regarding the role of adjuvant radiotherapy for colon cancer. Despite this, national consensus guidelines recommend consideration of radiation for patients with T4 colon cancer. Large comparative studies may be beneficial in clarifying the potential benefit of postoperative radiation for this cohort. METHOD We compared the overall survival between patients treated with surgery with and without adjuvant radiation using the National Cancer Database (NCDB) and the Surveillance, Epidemiology, and End Results Program (SEER), as well as disease-specific survival using SEER. Cox proportional hazards models and propensity score matching were used to adjust for relevant confounders. RESULTS There were a total of 18 776 patients in the NCDB cohort and 9926 patients in the SEER cohort. After propensity score matching, there was no statistically significant difference in overall mortality between surgery with and without radiation in the NCDB [hazard ratio (HR) 1.11; 95% CI 0.93-1.31; P = 0.25] or in SEER (HR 1.20; 95% CI 0.84-1.72; P = 0.32). Additionally, using SEER, we found no statistically significant difference in disease-specific mortality between these two groups (HR 1.13; 95% CI 0.76-1.67; P = 0.54). CONCLUSION Using the NCDB and SEER, we found no statistically significant difference in overall survival or disease-specific survival between patients treated with and without adjuvant radiation. Further studies should evaluate the impact of adjuvant radiotherapy on local control and prevention of recurrence-related morbidity in patients with T4 colon cancer.
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Affiliation(s)
- N T Sebastian
- Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA
| | - Y Tan
- Department of Biomedical Informatics, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - E D Miller
- Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA
| | - T M Williams
- Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA
| | - D A Diaz
- Department of Radiation Oncology, Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA
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33
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Pagano AM, Atwood TC, Durner GM, Williams TM. The seasonal energetic landscape of an apex marine carnivore, the polar bear. Ecology 2020; 101:e02959. [DOI: 10.1002/ecy.2959] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/22/2019] [Accepted: 11/12/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Anthony M. Pagano
- U.S. Geological SurveyAlaska Science Center4210 University Drive Anchorage Alaska99508USA
- Department of Ecology & Evolutionary Biology University of California Santa Cruz 130 McAllister Way Santa Cruz California95060USA
| | - Todd C. Atwood
- U.S. Geological SurveyAlaska Science Center4210 University Drive Anchorage Alaska99508USA
| | - George M. Durner
- U.S. Geological SurveyAlaska Science Center4210 University Drive Anchorage Alaska99508USA
| | - Terrie M. Williams
- Department of Ecology & Evolutionary Biology University of California Santa Cruz 130 McAllister Way Santa Cruz California95060USA
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34
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Affiliation(s)
- Terrie M Williams
- Department of Ecology and Evolutionary Biology, 130 McAllister Way, University of California-Santa Cruz, CA 95060, USA.
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35
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Wainwright DK, Fish FE, Ingersoll S, Williams TM, St Leger J, Smits AJ, Lauder GV. How smooth is a dolphin? The ridged skin of odontocetes. Biol Lett 2019; 15:20190103. [PMID: 31311484 DOI: 10.1098/rsbl.2019.0103] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Dolphin skin has long been an inspiration for research on drag reduction mechanisms due to the presence of skin ridges that could reduce fluid resistance. We gathered in vivo three-dimensional surface data on the skin from five species of odontocetes to quantitatively examine skin texture, including the presence and size of ridges. We used these data to calculate k+ values, which relate surface geometry to changes in boundary layer flow. Our results showed that while ridge size differs among species, odontocete skin was surprisingly smooth compared to the skin of other swimmers (average roughness = 5.3 µm). In addition, the presence of ridges was variable among individuals of the same species. We predict that odontocete skin ridges do not alter boundary layer flows at cruising swimming speeds. By combining k+ values and morphological data, our work provides evidence that skin ridges are unlikely to be an adaptation for drag reduction and that odontocete skin is exceptionally smooth compared to other pelagic swimmers.
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Affiliation(s)
- Dylan K Wainwright
- Organismic and Evolutionary Biology, Harvard University, Museum of Comparative Zoology, Cambridge, MA 02138, USA
| | - Frank E Fish
- Department of Biology, West Chester University, West Chester, PA 19383, USA
| | - Sam Ingersoll
- Organismic and Evolutionary Biology, Harvard University, Museum of Comparative Zoology, Cambridge, MA 02138, USA
| | - Terrie M Williams
- Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | | | - Alexander J Smits
- Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA
| | - George V Lauder
- Organismic and Evolutionary Biology, Harvard University, Museum of Comparative Zoology, Cambridge, MA 02138, USA
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36
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Pagano AM, Williams TM. Estimating the energy expenditure of free-ranging polar bears using tri-axial accelerometers: A validation with doubly labeled water. Ecol Evol 2019; 9:4210-4219. [PMID: 31015999 PMCID: PMC6468055 DOI: 10.1002/ece3.5053] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 02/13/2019] [Accepted: 02/19/2019] [Indexed: 01/27/2023] Open
Abstract
Measures of energy expenditure can be used to inform animal conservation and management, but methods for measuring the energy expenditure of free-ranging animals have a variety of limitations. Advancements in biologging technologies have enabled the use of dynamic body acceleration derived from accelerometers as a proxy for energy expenditure. Although dynamic body acceleration has been shown to strongly correlate with oxygen consumption in captive animals, it has been validated in only a few studies on free-ranging animals. Here, we use relationships between oxygen consumption and overall dynamic body acceleration in resting and walking polar bears Ursus maritimus and published values for the costs of swimming in polar bears to estimate the total energy expenditure of 6 free-ranging polar bears that were primarily using the sea ice of the Beaufort Sea. Energetic models based on accelerometry were compared to models of energy expenditure on the same individuals derived from doubly labeled water methods. Accelerometer-based estimates of energy expenditure on average predicted total energy expenditure to be 30% less than estimates derived from doubly labeled water. Nevertheless, accelerometer-based measures of energy expenditure strongly correlated (r 2 = 0.70) with measures derived from doubly labeled water. Our findings highlight the strengths and limitations in dynamic body acceleration as a measure of total energy expenditure while also further supporting its use as a proxy for instantaneous, detailed energy expenditure in free-ranging animals.
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Affiliation(s)
- Anthony M. Pagano
- Alaska Science CenterU.S. Geological SurveyAnchorageAlaska
- Present address:
Institute for Conservation ResearchSan Diego Zoo GlobalSan DiegoCalifornia
| | - Terrie M. Williams
- Department of Ecology & Evolutionary BiologyUniversity of California, Santa CruzSanta CruzCalifornia
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37
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Suraci JP, Frank LG, Oriol‐Cotterill A, Ekwanga S, Williams TM, Wilmers CC. Behavior‐specific habitat selection by African lions may promote their persistence in a human‐dominated landscape. Ecology 2019; 100:e02644. [DOI: 10.1002/ecy.2644] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 12/12/2018] [Accepted: 01/14/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Justin P. Suraci
- Center for Integrated Spatial Research Environmental Studies Department University of California Santa Cruz California 95064 USA
| | - Laurence G. Frank
- Living with Lions Mpala Research Centre Nanyuki 10400 Kenya
- Museum of Vertebrate Zoology University of California Berkeley California 94720 USA
| | - Alayne Oriol‐Cotterill
- Wildlife Conservation Research Unit Zoology Department Oxford University Abingdon OX13 5QL United Kingdom
- Lion Landscapes Highcliffe, New Road Teignmouth TQ14 8UL United Kingdom
| | - Steve Ekwanga
- Living with Lions Mpala Research Centre Nanyuki 10400 Kenya
| | - Terrie M. Williams
- Department of Ecology and Evolutionary Biology University of California Santa Cruz California 95064 USA
| | - Christopher C. Wilmers
- Center for Integrated Spatial Research Environmental Studies Department University of California Santa Cruz California 95064 USA
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38
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Pagano AM, Carnahan AM, Robbins CT, Owen MA, Batson T, Wagner N, Cutting A, Nicassio-Hiskey N, Hash A, Williams TM. Energetic costs of locomotion in bears: is plantigrade locomotion energetically economical? ACTA ACUST UNITED AC 2018; 221:221/12/jeb175372. [PMID: 29921569 DOI: 10.1242/jeb.175372] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 04/21/2018] [Indexed: 02/05/2023]
Abstract
Ursids are the largest mammals to retain a plantigrade posture. This primitive posture has been proposed to result in reduced locomotor speed and economy relative to digitigrade and unguligrade species, particularly at high speeds. Previous energetics research on polar bears (Ursus maritimus) found locomotor costs were more than double predictions for similarly sized quadrupedal mammals, which could be a result of their plantigrade posture or due to adaptations to their Arctic marine existence. To evaluate whether polar bears are representative of terrestrial ursids or distinctly uneconomical walkers, this study measured the mass-specific metabolism, overall dynamic body acceleration, and gait kinematics of polar bears and grizzly bears (Ursus arctos) trained to rest and walk on a treadmill. At routine walking speeds, we found polar bears and grizzly bears exhibited similar costs of locomotion and gait kinematics, but differing measures of overall dynamic body acceleration. Minimum cost of transport while walking in the two species (2.21 J kg-1 m-1) was comparable to predictions for similarly sized quadrupedal mammals, but these costs doubled (4.42 J kg-1 m-1) at speeds ≥5.4 km h-1 Similar to humans, another large plantigrade mammal, bears appear to exhibit a greater economy while moving at slow speeds.
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Affiliation(s)
- Anthony M Pagano
- US Geological Survey, Alaska Science Center, 4210 University Dr., Anchorage, AK 99508, USA .,Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA
| | - Anthony M Carnahan
- School of the Environment and School of Biological Sciences, Washington State University, Pullman, WA 99164, USA
| | - Charles T Robbins
- School of the Environment and School of Biological Sciences, Washington State University, Pullman, WA 99164, USA
| | - Megan A Owen
- Institute for Conservation Research, San Diego Zoo Global, San Diego, CA 92027, USA
| | | | - Nate Wagner
- San Diego Zoo Global, San Diego, CA 92027, USA
| | | | | | - Amy Hash
- Oregon Zoo, Portland, OR 97221, USA
| | - Terrie M Williams
- Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA
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39
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Williams TM, Blackwell SB, Richter B, Sinding MHS, Heide-Jørgensen MP. Paradoxical escape responses by narwhals ( Monodon monoceros). Science 2018; 358:1328-1331. [PMID: 29217577 DOI: 10.1126/science.aao2740] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 11/06/2017] [Indexed: 11/02/2022]
Abstract
Until recent declines in Arctic sea ice levels, narwhals (Monodon monoceros) have lived in relative isolation from human perturbation and sustained predation pressures. The resulting naïvety has made this cryptic, deep-diving cetacean highly susceptible to disturbance, although quantifiable effects have been lacking. We deployed a submersible, animal-borne electrocardiograph-accelerometer-depth recorder to monitor physiological and behavioral responses of East Greenland narwhals after release from net entanglement and stranding. Escaping narwhals displayed a paradoxical cardiovascular down-regulation (extreme bradycardia with heart rate ≤4 beats per minute) superimposed on exercise up-regulation (stroke frequency >25 strokes per minute and energetic costs three to six times the resting rate of energy expenditure) that rapidly depleted onboard oxygen stores. We attribute this unusual reaction to opposing cardiovascular signals-from diving, exercise, and neurocognitive fear responses-that challenge physiological homeostasis.
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Affiliation(s)
- Terrie M Williams
- Coastal Biology Building, Department of Ecology and Evolutionary Biology, 130 McAllister Way, University of California, Santa Cruz (UCSC), Santa Cruz, CA 95060, USA
| | - Susanna B Blackwell
- Greeneridge Sciences, 90 Arnold Place, Suite D, Santa Barbara, CA 93117, USA
| | - Beau Richter
- Coastal Biology Building, Department of Ecology and Evolutionary Biology, 130 McAllister Way, University of California, Santa Cruz (UCSC), Santa Cruz, CA 95060, USA
| | - Mikkel-Holger S Sinding
- Center for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, DK-1350 Copenhagen, Denmark.,Greenland Institute of Natural Resources, c/o Greenland Representation, Strandgade 91, 2, DK-1401 Copenhagen K, Denmark
| | - Mads Peter Heide-Jørgensen
- Greenland Institute of Natural Resources, c/o Greenland Representation, Strandgade 91, 2, DK-1401 Copenhagen K, Denmark
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40
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Williams TM, Kendall TL, Richter BP, Ribeiro-French CR, John JS, Odell KL, Losch BA, Feuerbach DA, Stamper MA. Swimming and diving energetics in dolphins: a stroke-by-stroke analysis for predicting the cost of flight responses in wild odontocetes. ACTA ACUST UNITED AC 2017; 220:1135-1145. [PMID: 28298467 DOI: 10.1242/jeb.154245] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 01/07/2017] [Indexed: 11/20/2022]
Abstract
Exponential increases in hydrodynamic drag and physical exertion occur when swimmers move quickly through water, and underlie the preference for relatively slow routine speeds by marine mammals regardless of body size. Because of this and the need to balance limited oxygen stores when submerged, flight (escape) responses may be especially challenging for this group. To examine this, we used open-flow respirometry to measure the energetic cost of producing a swimming stroke during different levels of exercise in bottlenose dolphins (Tursiops truncatus). These data were then used to model the energetic cost of high-speed escape responses by other odontocetes ranging in mass from 42 to 2738 kg. The total cost per stroke during routine swimming by dolphins, 3.31±0.20 J kg-1 stroke-1, was doubled during maximal aerobic performance. A comparative analysis of locomotor costs (LC; in J kg-1 stroke-1), representing the cost of moving the flukes, revealed that LC during routine swimming increased with body mass (M) for odontocetes according to LC=1.46±0.0005M; a separate relationship described LC during high-speed stroking. Using these relationships, we found that continuous stroking coupled with reduced glide time in response to oceanic noise resulted in a 30.5% increase in metabolic rate in the beaked whale, a deep-diving odontocete considered especially sensitive to disturbance. By integrating energetics with swimming behavior and dive characteristics, this study demonstrates the physiological consequences of oceanic noise on diving mammals, and provides a powerful tool for predicting the biological significance of escape responses by cetaceans facing anthropogenic disturbances.
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Affiliation(s)
- Terrie M Williams
- Center for Ocean Health, Long Marine Laboratory, University of California, Santa Cruz, 115 MacAlister Way, Santa Cruz, CA 95060, USA
| | - Traci L Kendall
- Center for Ocean Health, Long Marine Laboratory, University of California, Santa Cruz, 115 MacAlister Way, Santa Cruz, CA 95060, USA
| | - Beau P Richter
- Center for Ocean Health, Long Marine Laboratory, University of California, Santa Cruz, 115 MacAlister Way, Santa Cruz, CA 95060, USA
| | - Courtney R Ribeiro-French
- Center for Ocean Health, Long Marine Laboratory, University of California, Santa Cruz, 115 MacAlister Way, Santa Cruz, CA 95060, USA
| | - Jason S John
- Center for Ocean Health, Long Marine Laboratory, University of California, Santa Cruz, 115 MacAlister Way, Santa Cruz, CA 95060, USA
| | - Kim L Odell
- Epcot's The Seas, Walt Disney World Resorts™, Lake Buena Vista, FL 32830-1000, USA
| | - Barbara A Losch
- Epcot's The Seas, Walt Disney World Resorts™, Lake Buena Vista, FL 32830-1000, USA
| | - David A Feuerbach
- Epcot's The Seas, Walt Disney World Resorts™, Lake Buena Vista, FL 32830-1000, USA
| | - M Andrew Stamper
- Epcot's The Seas, Walt Disney World Resorts™, Lake Buena Vista, FL 32830-1000, USA
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41
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Bryce CM, Wilmers CC, Williams TM. Energetics and evasion dynamics of large predators and prey: pumas vs. hounds. PeerJ 2017; 5:e3701. [PMID: 28828280 PMCID: PMC5563439 DOI: 10.7717/peerj.3701] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 07/26/2017] [Indexed: 01/17/2023] Open
Abstract
Quantification of fine-scale movement, performance, and energetics of hunting by large carnivores is critical for understanding the physiological underpinnings of trophic interactions. This is particularly challenging for wide-ranging terrestrial canid and felid predators, which can each affect ecosystem structure through distinct hunting modes. To compare free-ranging pursuit and escape performance from group-hunting and solitary predators in unprecedented detail, we calibrated and deployed accelerometer-GPS collars during predator-prey chase sequences using packs of hound dogs (Canis lupus familiaris, 26 kg, n = 4-5 per chase) pursuing simultaneously instrumented solitary pumas (Puma concolor, 60 kg, n = 2). We then reconstructed chase paths, speed and turning angle profiles, and energy demands for hounds and pumas to examine performance and physiological constraints associated with cursorial and cryptic hunting modes, respectively. Interaction dynamics revealed how pumas successfully utilized terrain (e.g., fleeing up steep, wooded hillsides) as well as evasive maneuvers (e.g., jumping into trees, running in figure-8 patterns) to increase their escape distance from the overall faster hounds (avg. 2.3× faster). These adaptive strategies were essential to evasion in light of the mean 1.6× higher mass-specific energetic costs of the chase for pumas compared to hounds (mean: 0.76 vs. 1.29 kJ kg-1 min-1, respectively). On an instantaneous basis, escapes were more costly for pumas, requiring exercise at ≥90% of predicted [Formula: see text] and consuming as much energy per minute as approximately 5 min of active hunting. Our results demonstrate the marked investment of energy for evasion by a large, solitary carnivore and the advantage of dynamic maneuvers to postpone being overtaken by group-hunting canids.
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Affiliation(s)
- Caleb M. Bryce
- Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA, United States of America
- Botswana Predator Conservation Trust, Maun, Botswana
| | - Christopher C. Wilmers
- Center for Integrated Spatial Research, Environmental Studies Department, University of California, Santa Cruz, CA, United States of America
| | - Terrie M. Williams
- Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA, United States of America
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Affiliation(s)
- Christopher C. Wilmers
- Department of Environmental Studies Center for Integrated Spatial Research University of California Santa Cruz California 95064 USA
- Mpala Research Centre P.O. Box 555 Nanyuki 10400 Kenya
| | - Lynne A. Isbell
- Mpala Research Centre P.O. Box 555 Nanyuki 10400 Kenya
- Department of Anthropology and Animal Behavior Graduate Group University of California Davis California 95616 USA
| | - Justin P. Suraci
- Department of Environmental Studies Center for Integrated Spatial Research University of California Santa Cruz California 95064 USA
| | - Terrie M. Williams
- Mpala Research Centre P.O. Box 555 Nanyuki 10400 Kenya
- Department of Ecology and Evolutionary Biology University of California Santa Cruz California 95060 USA
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Thometz NM, Dearolf JL, Dunkin RC, Noren DP, Holt MM, Sims OC, Cathey BC, Williams TM. Comparative physiology of vocal musculature in two odontocetes, the bottlenose dolphin (Tursiops truncatus) and the harbor porpoise (Phocoena phocoena). J Comp Physiol B 2017; 188:177-193. [PMID: 28569355 DOI: 10.1007/s00360-017-1106-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 05/11/2017] [Indexed: 10/19/2022]
Abstract
The mechanism by which odontocetes produce sound is unique among mammals. To gain insight into the physiological properties that support sound production in toothed whales, we examined myoglobin content ([Mb]), non-bicarbonate buffering capacity (β), fiber-type profiles, and myosin heavy chain expression of vocal musculature in two odontocetes: the bottlenose dolphin (Tursiops truncatus; n = 4) and the harbor porpoise (Phocoena phocoena; n = 5). Both species use the same anatomical structures to produce sound, but differ markedly in their vocal repertoires. Tursiops produce both broadband clicks and tonal whistles, while Phocoena only produce higher frequency clicks. Specific muscles examined in this study included: (1) the nasal musculature around the phonic lips on the right (RNM) and left (LNM) sides of the head, (2) the palatopharyngeal sphincter (PPS), which surrounds the larynx and aids in pressurizing cranial air spaces, and (3) the genioglossus complex (GGC), a group of muscles positioned ventrally within the head. Overall, vocal muscles had significantly lower [Mb] and β than locomotor muscles from the same species. The PPS was predominately composed of small diameter slow-twitch fibers. Fiber-type and myosin heavy chain analyses revealed that the GGC was comprised largely of fast-twitch fibers (Tursiops: 88.6%, Phocoena: 79.7%) and had the highest β of all vocal muscles. Notably, there was a significant difference in [Mb] between the RNM and LNM in Tursiops, but not Phocoena. Our results reveal shared physiological characteristics of individual vocal muscles across species that enhance our understanding of key functional roles, as well as species-specific differences which appear to reflect differences in vocal capacities.
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Affiliation(s)
- Nicole M Thometz
- Department of Biology, University of San Francisco, 2130 Fulton St, San Francisco, CA, 94117, USA. .,Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 115 McAllister Way, Santa Cruz, CA, 95060, USA.
| | - Jennifer L Dearolf
- Biology Department, Hendrix College, 1600 Washington Ave., Conway, AR, 72032, USA
| | - Robin C Dunkin
- Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 115 McAllister Way, Santa Cruz, CA, 95060, USA
| | - Dawn P Noren
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, WA, 98112, USA
| | - Marla M Holt
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, WA, 98112, USA
| | - Olivia C Sims
- Biology Department, Hendrix College, 1600 Washington Ave., Conway, AR, 72032, USA
| | - Brandon C Cathey
- Biology Department, Hendrix College, 1600 Washington Ave., Conway, AR, 72032, USA
| | - Terrie M Williams
- Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 115 McAllister Way, Santa Cruz, CA, 95060, USA
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Pagano AM, Rode KD, Cutting A, Owen MA, Jensen S, Ware JV, Robbins CT, Durner GM, Atwood TC, Obbard ME, Middel KR, Thiemann GW, Williams TM. Using tri-axial accelerometers to identify wild polar bear behaviors. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00779] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Williams TM, Baxi RP, Ahluwalia PK, Haynes R. Is Single Incision Laparoscopy Associated with Increased Incidence of Incisional Umbilical Hernia? J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Baxi RP, Williams TM, Ahluwalia PK, Grinstead JA. HER vs HEM: A Comparative Analysis of Pathology from Hysteroscopic Endometrial Resection (HER) versus Hysteroscopic Endometrial Morcellation (HEM) Procedures. J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Thometz NM, Kendall TL, Richter BP, Williams TM. The high cost of reproduction in sea otters necessitates unique physiological adaptations. J Exp Biol 2016; 219:2260-4. [PMID: 27489214 DOI: 10.1242/jeb.138891] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/16/2016] [Indexed: 11/20/2022]
Abstract
Superimposed on inherently high basal metabolic demands, the additional energetic requirements of reproduction can push female sea otters beyond physiological limits. Indeed, the resulting energy imbalance contributes to disproportionately high rates of mortality at the end of lactation in this species. To examine and quantify metabolic changes associated with reproduction, we measured the resting metabolic rate (RMR) of a female sea otter across gestation, lactation and non-reproductive periods. Concurrently, measurements were made on a non-breeding control female. Our results suggest that RMR declines during gestation. Conversely, RMR increases during lactation, reaches a peak at 3-4 months postpartum, and remains elevated until weaning. Combining these direct measurements with published data, we found the cost of pup rearing to be significantly higher than previously estimated. High baseline energy demands and limited energy reserves, combined with significant lactation and pup rearing costs, appear to necessitate metabolic and thermal lability during key reproductive stages.
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Affiliation(s)
- Nicole M Thometz
- Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Traci L Kendall
- Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Beau P Richter
- Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA
| | - Terrie M Williams
- Department of Ecology and Evolutionary Biology, Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA
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Carhart-Harris RL, Kaelen M, Bolstridge M, Williams TM, Williams LT, Underwood R, Feilding A, Nutt DJ. The paradoxical psychological effects of lysergic acid diethylamide (LSD). Psychol Med 2016; 46:1379-1390. [PMID: 26847689 DOI: 10.1017/s0033291715002901] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Lysergic acid diethylamide (LSD) is a potent serotonergic hallucinogen or psychedelic that modulates consciousness in a marked and novel way. This study sought to examine the acute and mid-term psychological effects of LSD in a controlled study. METHOD A total of 20 healthy volunteers participated in this within-subjects study. Participants received LSD (75 µg, intravenously) on one occasion and placebo (saline, intravenously) on another, in a balanced order, with at least 2 weeks separating sessions. Acute subjective effects were measured using the Altered States of Consciousness questionnaire and the Psychotomimetic States Inventory (PSI). A measure of optimism (the Revised Life Orientation Test), the Revised NEO Personality Inventory, and the Peter's Delusions Inventory were issued at baseline and 2 weeks after each session. RESULTS LSD produced robust psychological effects; including heightened mood but also high scores on the PSI, an index of psychosis-like symptoms. Increased optimism and trait openness were observed 2 weeks after LSD (and not placebo) and there were no changes in delusional thinking. CONCLUSIONS The present findings reinforce the view that psychedelics elicit psychosis-like symptoms acutely yet improve psychological wellbeing in the mid to long term. It is proposed that acute alterations in mood are secondary to a more fundamental modulation in the quality of cognition, and that increased cognitive flexibility subsequent to serotonin 2A receptor (5-HT2AR) stimulation promotes emotional lability during intoxication and leaves a residue of 'loosened cognition' in the mid to long term that is conducive to improved psychological wellbeing.
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Affiliation(s)
- R L Carhart-Harris
- Imperial College London,Centre for Neuropsychopharmacology,Division of Brain Sciences,Faculty of Medicine,London,UK
| | - M Kaelen
- Imperial College London,Centre for Neuropsychopharmacology,Division of Brain Sciences,Faculty of Medicine,London,UK
| | - M Bolstridge
- Imperial College London,Centre for Neuropsychopharmacology,Division of Brain Sciences,Faculty of Medicine,London,UK
| | - T M Williams
- Department of Psychiatry,The University of Bristol,Bristol,UK
| | - L T Williams
- Imperial College London,Centre for Neuropsychopharmacology,Division of Brain Sciences,Faculty of Medicine,London,UK
| | - R Underwood
- Institute of Psychiatry, Psychology & Neuroscience,Department of Psychology,King's College London,London,UK
| | - A Feilding
- The Beckley Foundation,Beckley Park,Oxford,UK
| | - D J Nutt
- Imperial College London,Centre for Neuropsychopharmacology,Division of Brain Sciences,Faculty of Medicine,London,UK
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Maresh JL, Adachi T, Takahashi A, Naito Y, Crocker DE, Horning M, Williams TM, Costa DP. Summing the strokes: energy economy in northern elephant seals during large-scale foraging migrations. Mov Ecol 2015; 3:22. [PMID: 26380090 PMCID: PMC4570705 DOI: 10.1186/s40462-015-0049-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 08/26/2015] [Indexed: 06/01/2023]
Abstract
BACKGROUND The energy requirements of free-ranging marine mammals are challenging to measure due to cryptic and far-ranging feeding habits, but are important to quantify given the potential impacts of high-level predators on ecosystems. Given their large body size and carnivorous lifestyle, we would predict that northern elephant seals (Mirounga angustirostris) have elevated field metabolic rates (FMRs) that require high prey intake rates, especially during pregnancy. Disturbance associated with climate change or human activity is predicted to further elevate energy requirements due to an increase in locomotor costs required to accommodate a reduction in prey or time available to forage. In this study, we determined the FMRs, total energy requirements, and energy budgets of adult, female northern elephant seals. We also examined the impact of increased locomotor costs on foraging success in this species. RESULTS Body size, time spent at sea and reproductive status strongly influenced FMR. During the short foraging migration, FMR averaged 90.1 (SE = 1.7) kJ kg(-1)d(-1) - only 36 % greater than predicted basal metabolic rate. During the long migration, when seals were pregnant, FMRs averaged 69.4 (±3.0) kJ kg(-1)d(-1) - values approaching those predicted to be necessary to support basal metabolism in mammals of this size. Low FMRs in pregnant seals were driven by hypometabolism coupled with a positive feedback loop between improving body condition and reduced flipper stroking frequency. In contrast, three additional seals carrying large, non-streamlined instrumentation saw a four-fold increase in energy partitioned toward locomotion, resulting in elevated FMRs and only half the mass gain of normally-swimming study animals. CONCLUSIONS These results highlight the importance of keeping locomotion costs low for successful foraging in this species. In preparation for lactation and two fasting periods with high demands on energy reserves, migrating elephant seals utilize an economical foraging strategy whereby energy savings from reduced locomotion costs are shuttled towards somatic growth and fetal gestation. Remarkably, the energy requirements of this species, particularly during pregnancy, are 70-80 % lower than expected for mammalian carnivores, approaching or even falling below values predicted to be necessary to support basal metabolism in mammals of this size.
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Affiliation(s)
- JL Maresh
- />University of California Center for Ocean Health/Long Marine Lab, 100 Shaffer Rd., Santa Cruz, CA 95060 USA
| | - T. Adachi
- />Department of Polar Science, Graduate University for Advanced Studies, Midoricho Tachikawa, Japan
| | - A. Takahashi
- />Department of Polar Science, Graduate University for Advanced Studies, Midoricho Tachikawa, Japan
- />National Institute of Polar Research, Midoricho Tachikawa, Japan
| | - Y. Naito
- />National Institute of Polar Research, Midoricho Tachikawa, Japan
| | - DE Crocker
- />Department of Biology, Sonoma State University, Rohnert Park, USA
| | - M. Horning
- />Department of Fisheries & Wildlife, Marine Mammal Institute, Oregon State University, Newport, USA
| | - TM Williams
- />Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, USA
| | - DP Costa
- />Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, USA
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Abstract
The incidence of cardiovascular disease in humans is more than three times that of many wild and domestic mammals despite nearly identical heart morphologies and responses to exercise. A survey of mammalian species from 0.002-kg shrews to 43,000-kg whales shows that the human heart is more dog-like than cat-like and that neither body size nor longevity accounts for the relative vulnerability to cardiovascular disease. Rather, a major difference is daily activity patterns, which may underlie the comparatively healthy hearts of wild mammals.
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Affiliation(s)
- Terrie M. Williams
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California
| | - Penni Bengtson
- USAT Level II Certified Race Director-USAT Swim Task Force, Finish Line Productions, LLC, Boulder Creek, California
| | | | - Donald A. Croll
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California
| | - Randall W. Davis
- Deparments of Marine Biology and Wildlife and Fisheries Science, Texas A&M University, Galveston, Texas
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