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Giardino WJ, Rodriguez ED, Smith ML, Ford MM, Galili D, Mitchell SH, Chen A, Ryabinin AE. Control of chronic excessive alcohol drinking by genetic manipulation of the Edinger-Westphal nucleus urocortin-1 neuropeptide system. Transl Psychiatry 2017; 7:e1021. [PMID: 28140406 PMCID: PMC5299395 DOI: 10.1038/tp.2016.293] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/25/2016] [Accepted: 12/15/2016] [Indexed: 11/23/2022] Open
Abstract
Midbrain neurons of the centrally projecting Edinger-Westphal nucleus (EWcp) are activated by alcohol, and enriched with stress-responsive neuropeptide modulators (including the paralog of corticotropin-releasing factor, urocortin-1). Evidence suggests that EWcp neurons promote behavioral processes for alcohol-seeking and consumption, but a definitive role for these cells remains elusive. Here we combined targeted viral manipulations and gene array profiling of EWcp neurons with mass behavioral phenotyping in C57BL/6 J mice to directly define the links between EWcp-specific urocortin-1 expression and voluntary binge alcohol intake, demonstrating a specific importance for EWcp urocortin-1 activity in escalation of alcohol intake.
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Heilman RL, Mathur A, Smith ML, Kaplan B, Reddy KS. Increasing the Use of Kidneys From Unconventional and High-Risk Deceased Donors. Am J Transplant 2016; 16:3086-3092. [PMID: 27172238 DOI: 10.1111/ajt.13867] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/19/2016] [Accepted: 05/03/2016] [Indexed: 01/25/2023]
Abstract
In this paper, we have reviewed the literature and report on kidney donors that are currently used at relatively low rates. Kidneys from donors with acute kidney injury (AKI) seem to have outcomes equivalent to those from donors without AKI, provided one can rule out significant cortical necrosis. Kidneys from donors with preexisting diabetes or hypertension may have marginally lower aggregate survival but still provide patients with a significant benefit over remaining on the wait list. The Kidney Donor Profile Index derives only an aggregate association with survival with a very modest C statistic; therefore, the data indicated that this index should not be the sole reason to discard a kidney, except perhaps in patients with extremely low estimated posttransplant survival scores. It is important to note that the Scientific Registry of Transplant Recipients models of risk adjustment should allay concerns regarding regulatory issues for observed outcomes falling below expectations. The successful utilization of kidneys from donation after cardiac death over the past decade shows how expanding our thinking can translate into more patients benefiting from transplantation. Given the growing number of patients on the wait list, broadening our approach to kidney acceptance could have an important impact on the population with end-stage renal disease. Many lives could be prolonged by carefully considering use of kidneys that are often discarded.
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Demetris AJ, Bellamy C, Hübscher SG, O'Leary J, Randhawa PS, Feng S, Neil D, Colvin RB, McCaughan G, Fung JJ, Del Bello A, Reinholt FP, Haga H, Adeyi O, Czaja AJ, Schiano T, Fiel MI, Smith ML, Sebagh M, Tanigawa RY, Yilmaz F, Alexander G, Baiocchi L, Balasubramanian M, Batal I, Bhan AK, Bucuvalas J, Cerski CTS, Charlotte F, de Vera ME, ElMonayeri M, Fontes P, Furth EE, Gouw ASH, Hafezi-Bakhtiari S, Hart J, Honsova E, Ismail W, Itoh T, Jhala NC, Khettry U, Klintmalm GB, Knechtle S, Koshiba T, Kozlowski T, Lassman CR, Lerut J, Levitsky J, Licini L, Liotta R, Mazariegos G, Minervini MI, Misdraji J, Mohanakumar T, Mölne J, Nasser I, Neuberger J, O'Neil M, Pappo O, Petrovic L, Ruiz P, Sağol Ö, Sanchez Fueyo A, Sasatomi E, Shaked A, Shiller M, Shimizu T, Sis B, Sonzogni A, Stevenson HL, Thung SN, Tisone G, Tsamandas AC, Wernerson A, Wu T, Zeevi A, Zen Y. 2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection. Am J Transplant 2016; 16:2816-2835. [PMID: 27273869 DOI: 10.1111/ajt.13909] [Citation(s) in RCA: 364] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/01/2016] [Accepted: 05/25/2016] [Indexed: 02/06/2023]
Abstract
The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.
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Sargazi M, Smith ML, Worth RC, Roberts NB. A rare ganglioneuroblastoma secreting dopamine and the value of its measurement in diagnosis and prognosis. Ann Clin Biochem 2016; 43:73-6. [PMID: 16390613 DOI: 10.1258/000456306775141704] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A case is described of a patient with a ganglioneuroblastoma, initially located in the right adrenal, which produced an excess of dopamine (7646 and 7959 nmol/24 h), approximately two and a half times the upper limit of the normal daily urine output. The urinary excretion of noradrenaline, adrenaline and methylated derivatives was always within the normal reference ranges. The patient was generally well, with normal blood pressure and only mild flushes. Two years after surgical resection, recurrence was indicated by an increase in urinary dopamine (8507 nmol/24 h); it was located in the tumour bed and left side of the neck by CT and 123I MIBG scans. The patient was treated with a high dose of 131I MIBG, with subsequent reduction in dopamine production. This was repeated on four other occasions, the latest being in January 2005. The output of dopamine was thus used as a marker of tumour diagnosis and progression and it is recommended that the assay of dopamine be included in the screening of catecholamine-secreting tumours to avoid possible misdiagnosis.
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Canović EP, Zollinger AJ, Tam SN, Smith ML, Stamenović D. Tensional homeostasis in endothelial cells is a multicellular phenomenon. Am J Physiol Cell Physiol 2016; 311:C528-35. [PMID: 27488661 DOI: 10.1152/ajpcell.00037.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 07/28/2016] [Indexed: 01/19/2023]
Abstract
Mammalian cells of various types exhibit the remarkable ability to adapt to externally applied mechanical stresses and strains. Because of this adaptation, cells can maintain their endogenous mechanical tension at a preferred (homeostatic) level, which is essential for normal physiological functions of cells and tissues and provides protection against various diseases, including atherosclerosis and cancer. Conventional wisdom is that the cell possesses the ability to maintain tensional homeostasis on its own. Recent findings showed, however, that isolated cells cannot maintain tensional homeostasis. Here we studied the effect of multicellular interactions on tensional homeostasis by measuring traction forces in isolated bovine aortic endothelial cells and in confluent and nonconfluent cell clusters of different sizes. We found that, in isolated cells, the traction field exhibited a highly dynamic and erratic behavior. However, in cell clusters, dynamic fluctuations of the traction field became attenuated with increasing cluster size, at a rate that was faster in nonconfluent than confluent clusters. The driving mechanism of attenuation of traction field fluctuations was statistical averaging of the noise, and the impeding mechanism was nonuniform stress distribution in the clusters, which resulted from intercellular force transmission, known as a "global tug-of-war." These results show that isolated cells could not maintain tensional homeostasis, which confirms previous findings, and that tensional homeostasis is a multicellular phenomenon, which is a novel finding.
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Smith LN, Farooq AR, Smith ML, Ivanov IE, Orlando A. Realistic and interactive high-resolution 4D environments for real-time surgeon and patient interaction. Int J Med Robot 2016; 13. [PMID: 27439562 DOI: 10.1002/rcs.1761] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 05/24/2016] [Accepted: 06/10/2016] [Indexed: 01/13/2023]
Abstract
BACKGROUND Remote consultations that are realistic enough to be useful medically offer considerable clinical, logistical and cost benefits. Despite advances in virtual reality and vision hardware and software, these benefits are currently often unrealised. METHOD The proposed approach combines high spatial and temporal resolution 3D and 2D machine vision with virtual reality techniques, in order to develop new environments and instruments that will enable realistic remote consultations and the generation of new types of useful clinical data. RESULTS New types of clinical data have been generated for skin analysis and respiration measurement; and the combination of 3D with 2D data was found to offer potential for the generation of realistic virtual consultations. CONCLUSION An innovative combination of high resolution machine vision data and virtual reality online methods, promises to provide advanced functionality and significant medical benefits, particularly in regions where populations are dispersed or access to clinicians is limited. Copyright © 2016 John Wiley & Sons, Ltd.
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Ostwald MM, Smith ML, Seeley TD. The behavioral regulation of thirst, water collection and water storage in honey bee colonies. J Exp Biol 2016; 219:2156-65. [DOI: 10.1242/jeb.139824] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/10/2016] [Indexed: 11/20/2022]
Abstract
ABSTRACT
This study investigated how a honey bee colony develops and quenches its collective thirst when it experiences hyperthermia of its broodnest. We found that a colony must strongly boost its water intake because evaporative cooling is critical to relieving broodnest hyperthermia, and that it must rapidly boost its water intake because a colony maintains only a small water reserve. We also clarified how a colony's water collectors know when to spring into action – by sensing either more frequent requests for fluid or greater personal thirst, or both. Finally, we found that the behavioral flexibility of a colony's water collectors enables them not only to satisfy their colony's current water needs but also to buffer their colony against future extreme water stresses by storing water in their crops and in their combs.
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Gibson J, Smith ML, Xue RD, Ren DS. Evaluation of a New Thermal Fog Machine for Control of Adult Aedes albopictus in a Large Enclosed Space. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:167-170. [PMID: 27280358 DOI: 10.2987/moco-32-02-167-170.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Testing of the PSO BASDKA-AC1200 multifunction ultrafine particle atomization machine, a thermal fog machine, with Aqualuer 20-20(®) (permethrin 20.6%, piperonyl butoxide 20.6%) was conducted against Aedes albopictus. The machine was set at a 40 sec maximum burst interval dispersing 36 ml of chemical with an average droplet volume of 50%. Female adult Ae. albopictus were placed into cylindrical paper cages and adhered to poles at 5, 8, 10, 15, and 25 m from the center point of the machine. Control cages consisted of 1 cage placed at 5, 10, and 25 m. Control and treatment groups were left in the experiment area for 15 min. Initial knockdown after 15 min and 24 h mortality were documented. At 15 min post-treatment, Ae. albopictus displayed less than 50% knockdown. After 24 h, all treatment cages displayed greater than 90% mortality. Further bottle bioassays were conducted to determine the lowest chemical dose possible to achieve a lethal dose of 90%. A 1% dilution (10 ml Aqualuer 20-20 to 1,000 ml of polyether) of Aqualuer showed high mortality in the laboratory. However, after running 3 repetitions of a 1% dilution, there was no significant difference between the mortality of the mosquitoes at any of the distances 24 h post-treatment. This study indicates that the test machine would be an applicable and suitable machine for control of Ae. albopictus in enclosed spaces.
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Camelio K, Gibson J, Smith ML, Drake LL, Xue RD. Evaluation of Three Commercial Handheld Ultra-Low-Volume Foggers with Aqualure® 20-20 Against Adult Aedes albopictus. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:163-166. [PMID: 27280357 DOI: 10.2987/moco-32-02-163-166.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The Anastasia Mosquito Control District (AMCD) tests all equipment before field use to determine if machines are suitable for the needs of the district. Three handheld ultra-low-volume (ULV) foggers--the American LongRay (ULV) Fogger Model 3600B with rechargeable lithium battery (DC model), American LongRay ULV Fogger Model 3600E with 110V or 220V AC power (AC model), and Boston Fog Battery Motorized Fogger (Boston Fogger)--were compared to determine which fogger would be most suitable for use by AMCD. Mortality of caged Aedes albopictus was analyzed after 24 h to determine the success of a single application. All 3 foggers resulted in 100% mortality after 24 h using the insecticide Aqualuer 20-20 (active ingredients permethrin 20.6% and piperonyl butoxide 20.6%) 1:5 dilution with reverse osmosis water. Based on operator safety, robustness, and operational performance, the American LongRay DC model was found to be the most suitable at administering Aqualuer 20-20 against caged adult Ae. albopictus.
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Drake LL, Gibson J, Smith ML, Farooq M, Sallam MF, Xue RD. Evaluation of DeltaGard® Ground Application Against Aedes albopictus in a Residential Area in St. Augustine, Florida. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:160-162. [PMID: 27280356 DOI: 10.2987/moco-32-02-160-162.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Aedes albopictus is an invasive species that poses a health threat in many residential neighborhoods throughout Florida. Aedes albopictus is a high priority for mosquito control efforts in the state. The efficacy of DeltaGard(®) (AI 2% deltamethrin) application against Ae. albopictus was evaluated in a residential area in St. Augustine, FL. DeltaGard was applied using a truck-mounted ultra-low-volume aerosol generator along 3 streets in a residential neighborhood. Caged mosquito mortality and droplet density data were recorded. Leaf clippings from houses on treated streets were bioassayed against laboratory-reared Ae. albopictus. Overall, the DeltaGard application was found to be more effective in the front yard of the houses, resulting in 78.3% mortality in caged mosquitoes, 42 % mortality in leaf bioassays, and 50.5 nl/cc in spray density. Based on the amount of vegetation and residential barriers around the houses, the application caused only 46.3% mortality in caged mosquitoes, 7.5% mortality in leaf bioassays, and 5.4 nl/cc in spray density in the back yard sites.
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Schnurman Z, Smith ML, Kondziolka D. Off-label innovation: characterization through a case study of rhBMP-2 for spinal fusion. J Neurosurg Spine 2016; 25:406-14. [PMID: 27104282 DOI: 10.3171/2016.1.spine151192] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Off-label therapies are widely used in clinical practice by spinal surgeons. Some patients and practitioners have advocated for increased regulation of their use, and payers have increasingly questioned reimbursment for off-label therapies. In this study, the authors applied a model that quantifies publication data to analyze the developmental process from initial on-label use to off-label innovation, using as an example recombinant human bone morphogenetic protein 2 (rhBMP-2) because of its wide off-label use. METHODS As a case study of off-label innovation, the developmental patterns of rhBMP-2 from FDA-approved use for anterior lumbar interbody fusion to several of its off-label uses, including posterolateral lumbar fusion, anterior cervical discectomy and fusion, and posterior lumbar interbody fusion/transforaminal lumbar interbody fusion, were evaluated using the "progressive scholarly acceptance" (PSA) model. In this model, PSA is used as an end point indicating acceptance of a therapy or procedure by the relevant scientific community and is reached when the total number of peer-reviewed studies devoted to refinement or improvement of a therapy surpasses the total number assessing initial efficacy. Report characteristics, including the number of patients studied and study design, were assessed in addition to the time to and pattern of community acceptance, and results compared with previous developmental study findings. Disclosures and reported conflicts of interest for all articles were reviewed, and these data were also used in the analysis. RESULTS Publication data indicated that the acceptance of rhBMP-2 off-label therapies occurred more rapidly and with less evidence than previously studied on-label therapies. Additionally, the community appeared to respond more robustly (by rapidly changing publication patterns) to reports of adverse events than to new questions of efficacy. CONCLUSIONS The development of off-label therapies, including the influence of investigative methods, regulation, and changing perspectives, can be characterized on the basis of publication patterns. The approach and findings in this report could inform future off-label development of therapies and procedures as well as attempts to regulate off-label use.
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Loftus JC, Smith ML, Seeley TD. How Honey Bee Colonies Survive in the Wild: Testing the Importance of Small Nests and Frequent Swarming. PLoS One 2016; 11:e0150362. [PMID: 26968000 PMCID: PMC4788434 DOI: 10.1371/journal.pone.0150362] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/12/2016] [Indexed: 12/04/2022] Open
Abstract
The ectoparasitic mite, Varroa destructor, and the viruses that it transmits, kill the colonies of European honey bees (Apis mellifera) kept by beekeepers unless the bees are treated with miticides. Nevertheless, there exist populations of wild colonies of European honey bees that are persisting without being treated with miticides. We hypothesized that the persistence of these wild colonies is due in part to their habits of nesting in small cavities and swarming frequently. We tested this hypothesis by establishing two groups of colonies living either in small hives (42 L) without swarm-control treatments or in large hives (up to 168 L) with swarm-control treatments. We followed the colonies for two years and compared the two groups with respect to swarming frequency, Varroa infesttion rate, disease incidence, and colony survival. Colonies in small hives swarmed more often, had lower Varroa infestation rates, had less disease, and had higher survival compared to colonies in large hives. These results indicate that the smaller nest cavities and more frequent swarming of wild colonies contribute to their persistence without mite treatments.
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Fulcher A, Farooq M, Richardson AG, Smith ML, Scott JM, Gaines MK, Xue RD. Characteristics and Efficacy of Three Commercial Handheld Thermal Foggers with Pyrethroid Insecticides Against Three Species of Mosquitoes. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:44-50. [PMID: 27105215 DOI: 10.2987/8756-971x-32.1.44] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The field study's objectives were to compare the physical characteristics as well as efficacy with multiple insecticides for Bonide(®) Fog Rx Insect Fogger, Black Flag(®) Propane Insect Fogger, and Burgess(®) Outdoor Propane Insect Fogger. Evaluations were conducted with 7 machine chemical combinations, 3 depths of spray, and 3 species of laboratory-reared mosquitoes, Anopheles quadrimaculatus, Culex quinquefasciatus, and Aedes aegypti. Combinations of these factors were analyzed in conjunction with environmental parameters. Data showed statistical significance between all machines. The Bonide machine maintained integrity and durability for the longest period of time compared with the other 2 machines. When evaluating the 3 machines with DUET™, mortality was highest with the Bonide and lowest with the Burgess machine.
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Batra RK, Heilman RL, Smith ML, Thomas LF, Khamash HA, Katariya NN, Hewitt WR, Singer AL, Mathur AK, Huskey J, Chakkera HA, Moss A, Reddy KS. Rapid Resolution of Donor-Derived Glomerular Fibrin Thrombi After Deceased Donor Kidney Transplantation. Am J Transplant 2016; 16:1015-20. [PMID: 26689853 DOI: 10.1111/ajt.13561] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Revised: 09/11/2015] [Accepted: 09/29/2015] [Indexed: 01/25/2023]
Abstract
The aim of this study was to determine the clinical and histologic outcomes related to transplanting kidneys from deceased donors with glomerular fibrin thrombi (GFT). We included all cases transplanted between October 2003 and October 2014 that had either a preimplantation biopsy or an immediate postreperfusion biopsy showing GFT. The study cohort included 61 recipients (9.9%) with GFT and 557 in the control group without GFT. Delayed graft function occurred in 49% of the GFT group and 39% in the control group (p = 0.14). Serum creatinine at 1, 4, and 12 months and estimated GFR at 12 months were similar in the two groups. Estimated 1-year graft survival was 93.2% in the GFT group and 95.1% in the control group (p = 0.22 by log-rank). Fifty-two of the 61 patients in the GFT group (85%) had a 1-month protocol biopsy, and only two biopsies (4%) showed residual focal glomerular thrombi. At the 1-year protocol biopsy, the prevalence of moderate to severe interstitial fibrosis and tubular atrophy was 24% in the GFT group and 30% in the control group (p = 0.42). We concluded that GFT resolves rapidly after transplantation and that transplanting selected kidneys from deceased donors with GFT is a safe practice.
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Jouett NP, Moralez G, White DW, Eubank WL, Chen S, Tian J, Smith ML, Zimmerman MC, Raven PB. N-Acetylcysteine reduces hyperacute intermittent hypoxia-induced sympathoexcitation in human subjects. Exp Physiol 2016; 101:387-96. [PMID: 27027616 DOI: 10.1113/ep085546] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/12/2016] [Indexed: 01/31/2023]
Abstract
NEW FINDINGS What is the central question of this study? This study evaluated the following central question: does N-acetylcysteine (N-AC), an antioxidant that readily penetrates the blood-brain barrier, have the capability to reduce the increase in sympathetic nerve activity observed during hyperacute intermittent hypoxia? What is the main finding and its importance? We demonstrate that N-AC decreases muscle sympathetic nerve activity in response to hyperacute intermittent hypoxia versus placebo control. This finding suggests that antioxidants, such as N-AC, have therapeutic potential in obstructive sleep apnoea. This investigation tested the following hypotheses: that (i) N-acetylcysteine (N-AC) attenuates hyperacute intermittent hypoxia-induced sympathoexcitation, (ii) without elevating superoxide measured in peripheral venous blood. Twenty-eight healthy human subjects were recruited to the study. One hour before experimentation, each subject randomly ingested either 70 mg kg(-1) of N-AC (n = 16) or vehicle placebo (n = 12). Three-lead ECG and arterial blood pressure, muscle sympathetic nerve activity (n = 17) and whole-blood superoxide concentration (using electron paramagnetic resonance spectroscopy; n = 12) were measured. Subjects underwent a 20 min hyperacute intermittent hypoxia training (hAIHT) protocol that consisted of cyclical end-expiratory apnoeas with 100% nitrogen. N-AC decreased muscle sympathetic nerve activity after hAIHT compared with placebo (P < 0.02). However, N-AC did not alter superoxide concentrations in venous blood compared with placebo (P > 0.05). Moreover, hAIHT did not increase superoxide concentrations in the peripheral circulation as measured by electron paramagnetic resonance (P > 0.05). Based on these findings, we contend that (i) hAIHT and (ii) the actions of N-AC in hAIHT are primarily mediated centrally rather than peripherally, although central measurements of reactive oxygen species are difficult to obtain in human subjects, thus making this assertion difficult to verify. This investigation suggests the possibility of developing a pharmaceutical therapy to inhibit the sympathoexcitation associated with obstructive sleep apnoea.
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Jouett NP, Hardisty JM, Mason JR, Niv D, Romano JJ, Watenpaugh DE, Burk JR, Smith ML. Systolic pressure response to voluntary apnea predicts sympathetic tone in obstructive sleep apnea as a clinically useful index. Auton Neurosci 2016; 194:38-45. [DOI: 10.1016/j.autneu.2015.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 12/04/2015] [Accepted: 12/08/2015] [Indexed: 11/28/2022]
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Smith ML, Li J, Cote DM, Ryabinin AE. Effects of isoflurane and ethanol administration on c-Fos immunoreactivity in mice. Neuroscience 2015; 316:337-43. [PMID: 26742790 DOI: 10.1016/j.neuroscience.2015.12.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 11/17/2015] [Accepted: 12/25/2015] [Indexed: 11/19/2022]
Abstract
Noninvasive functional imaging holds great promise for the future of translational research, due to the ability to directly compare between preclinical and clinical models of psychiatric disorders. Despite this potential, concerns have been raised regarding the necessity to anesthetize rodent and monkey subjects during these procedures, because anesthetics may alter neuronal activity. For example, in studies on drugs of abuse and alcohol, it is not clear to what extent anesthesia can interfere with drug-induced neural activity. Therefore, the current study investigated whole-brain c-Fos activation following isoflurane anesthesia as well as ethanol-induced activation of c-Fos in anesthetized mice. In the first experiment, we examined effects of one or three sessions of gaseous isoflurane on c-Fos activation across the brain in male C57BL/6J mice. Isoflurane administration led to c-Fos activation in several areas, including the piriform cortex and lateral septum. Lower or similar levels of activation in these areas were detected after three sessions of isoflurane, suggesting that multiple exposures may eliminate some of the enhanced neuronal activation caused by acute isoflurane. In the second experiment, we investigated the ability of ethanol injection (1.5 or 2.5g/kgi.p.) to induce c-Fos activation under anesthesia. Following three sessions of isoflurane, 1.5g/kg of ethanol induced c-Fos in the central nucleus of amygdala and the centrally-projecting Edinger-Westphal nucleus (EWcp). This induction was lower after 2.5g/kg of ethanol. These results demonstrate that ethanol-induced neural activation can be detected in the presence of isoflurane anesthesia. They also suggest, that while habituation to isoflurane helps reduce neuronal activation, interaction between effects of anesthesia and alcohol can occur. Studies using fMRI imaging could benefit from using habituated animals and dose-response analyses.
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Hubbard B, Buczek-Thomas JA, Nugent MA, Smith ML. Fibronectin Fiber Extension Decreases Cell Spreading and Migration. J Cell Physiol 2015; 231:1728-36. [DOI: 10.1002/jcp.25271] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 11/30/2015] [Indexed: 12/25/2022]
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Han JH, Zhang F, Kadis DS, Houston LM, Samy RN, Smith ML, Dimitrijevic A. Auditory cortical activity to different voice onset times in cochlear implant users. Clin Neurophysiol 2015; 127:1603-1617. [PMID: 26616545 DOI: 10.1016/j.clinph.2015.10.049] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 10/20/2015] [Accepted: 10/28/2015] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Voice onset time (VOT) is a critical temporal cue for perception of speech in cochlear implant (CI) users. We assessed the cortical auditory evoked potentials (CAEPs) to consonant vowels (CVs) with varying VOTs and related these potentials to various speech perception measures. METHODS CAEPs were recorded from 64 scalp electrodes during passive listening in CI and normal-hearing (NH) groups. Speech stimuli were synthesized CVs from a 6-step VOT /ba/-/pa/ continuum ranging from 0 to 50 ms VOT in 10-ms steps. Behavioral measures included the 50% boundary point for categorical perception ("ba" to "pa") from an active condition task. RESULTS Behavioral measures: CI users with poor speech perception performance had prolonged 50% VOT boundary points compared to NH subjects. The 50% boundary point was also significantly correlated to the ability to discriminate consonants in quiet and noise masking. Electrophysiology: The most striking difference between the NH and CI subjects was that the P2 response was significantly reduced in amplitude in the CI group compared to NH. N1 amplitude did not differ between NH and CI groups. P2 latency increased with increases in VOT for both NH and CI groups. P2 was delayed more in CI users with poor speech perception compared to NH subjects. N1 amplitude was significantly related to consonant perception in noise while P2 latency was significantly related to vowel perception in noise. When dipole source modelling in auditory cortex was used to characterize N1/P2, more significant relationships were observed with speech perception measures compared to the same N1/P2 activity when measured at the scalp. N1 dipole amplitude measures were significantly correlated with consonants in noise discrimination. Like N1, the P2 dipole amplitude was correlated with consonant discrimination, but additional significant relationships were observed such as sentence and word identification. CONCLUSIONS P2 responses to a VOT continuum stimulus were different between NH subjects and CI users. P2 responses show more significant relationships with speech perception than N1 responses. SIGNIFICANCE The current findings indicate that N1/P2 measures during a passive listening task relate to speech perception outcomes after cochlear implantation.
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95
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Vogan VM, Morgan BR, Powell TL, Smith ML, Taylor MJ. The neurodevelopmental differences of increasing verbal working memory demand in children and adults. Dev Cogn Neurosci 2015; 17:19-27. [PMID: 26615571 PMCID: PMC6990091 DOI: 10.1016/j.dcn.2015.10.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 08/26/2015] [Accepted: 10/13/2015] [Indexed: 01/10/2023] Open
Abstract
Working memory (WM) – temporary storage and manipulation of information in the mind – is a key component of cognitive maturation, and structural brain changes throughout development are associated with refinements in WM. Recent functional neuroimaging studies have shown that there is greater activation in prefrontal and parietal brain regions with increasing age, with adults showing more refined, localized patterns of activations. However, few studies have investigated the neural basis of verbal WM development, as the majority of reports examine visuo-spatial WM. We used fMRI and a 1-back verbal WM task with six levels of difficulty to examine the neurodevelopmental changes in WM function in 40 participants, twenty-four children (ages 9–15 yr) and sixteen young adults (ages 20–25 yr). Children and adults both demonstrated an opposing system of cognitive processes with increasing cognitive demand, where areas related to WM (frontal and parietal regions) increased in activity, and areas associated with the default mode network decreased in activity. Although there were many similarities in the neural activation patterns associated with increasing verbal WM capacity in children and adults, significant changes in the fMRI responses were seen with age. Adults showed greater load-dependent changes than children in WM in the bilateral superior parietal gyri, inferior frontal and left middle frontal gyri and right cerebellum. Compared to children, adults also showed greater decreasing activation across WM load in the bilateral anterior cingulate, anterior medial prefrontal gyrus, right superior lateral temporal gyrus and left posterior cingulate. These results demonstrate that while children and adults activate similar neural networks in response to verbal WM tasks, the extent to which they rely on these areas in response to increasing cognitive load evolves between childhood and adulthood.
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96
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Dearden JC, Hewitt M, Roberts DW, Enoch SJ, Rowe PH, Przybylak KR, Vaughan-Williams GD, Smith ML, Pillai GG, Katritzky AR. Mechanism-Based QSAR Modeling of Skin Sensitization. Chem Res Toxicol 2015; 28:1975-86. [PMID: 26382665 DOI: 10.1021/acs.chemrestox.5b00197] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Many chemicals can induce skin sensitization, and there is a pressing need for non-animal methods to give a quantitative indication of potency. Using two large published data sets of skin sensitizers, we have allocated each sensitizing chemical to one of 10 mechanistic categories and then developed good QSAR models for the seven categories that have a sufficient number of chemicals to allow modeling. Both internal and external validation checks showed that each model had good predictivity.
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97
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Heilman RL, Smith ML, Reddy KS. Utilization of Kidneys With Acute Kidney Injury in the Extended Criteria Donor Setting. Am J Transplant 2015; 15:2783. [PMID: 26211677 DOI: 10.1111/ajt.13392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 05/20/2015] [Indexed: 01/25/2023]
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98
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Pohlmann-Eden B, Aldenkamp A, Baker GA, Brandt C, Cendes F, Coras R, Crocker CE, Helmstaedter C, Jones-Gotman M, Kanner AM, Mazarati A, Mula M, Smith ML, Omisade A, Tellez-Zenteno J, Hermann BP. The relevance of neuropsychiatric symptoms and cognitive problems in new-onset epilepsy - Current knowledge and understanding. Epilepsy Behav 2015; 51:199-209. [PMID: 26291774 DOI: 10.1016/j.yebeh.2015.07.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 07/03/2015] [Indexed: 01/11/2023]
Abstract
Neurobehavioral and cognition problems are highly prevalent in epilepsy, but most research studies to date have not adequately addressed the precise nature of the relationship between these comorbidities and seizures. To address this complex issue and to facilitate collaborative, innovative research in the rising field of neurobehavioral comorbidities and cognition disturbances in new-onset epilepsy, international epilepsy experts met at the 3rd Halifax International Epilepsy Conference & Retreat at White Point, South Shore, Nova Scotia, Canada from September 18 to 20, 2014. This Conference Proceedings provides a summary of the conference proceedings. Specifically, the following topics are discussed: (i) role of comorbidities in epilepsy diagnosis and management, (ii) role of antiepileptic medications in understanding the relationship between epilepsy and neurobehavioral and cognition problems, and (iii) animal data and diagnostic approaches. Evidence to date, though limited, strongly suggests a bidirectional relationship between epilepsy and cognitive and psychiatric comorbidities. In fact, it is likely that seizures and neurobehavioral problems represent different symptoms of a common etiology or network-wide disturbance. As a reflection of this shared network, psychiatric comorbidities and/or cognition problems may actually precede the seizure occurrence and likely get often missed if not screened.
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99
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Kubow KE, Vukmirovic R, Zhe L, Klotzsch E, Smith ML, Gourdon D, Luna S, Vogel V. Mechanical forces regulate the interactions of fibronectin and collagen I in extracellular matrix. Nat Commun 2015; 6:8026. [PMID: 26272817 PMCID: PMC4539566 DOI: 10.1038/ncomms9026] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 07/09/2015] [Indexed: 12/11/2022] Open
Abstract
Despite the crucial role of extracellular matrix (ECM) in directing cell fate in healthy and diseased tissues--particularly in development, wound healing, tissue regeneration and cancer--the mechanisms that direct the assembly and regulate hierarchical architectures of ECM are poorly understood. Collagen I matrix assembly in vivo requires active fibronectin (Fn) fibrillogenesis by cells. Here we exploit Fn-FRET probes as mechanical strain sensors and demonstrate that collagen I fibres preferentially co-localize with more-relaxed Fn fibrils in the ECM of fibroblasts in cell culture. Fibre stretch-assay studies reveal that collagen I's Fn-binding domain is responsible for the mechano-regulated interaction. Furthermore, we show that Fn-collagen interactions are reciprocal: relaxed Fn fibrils act as multivalent templates for collagen assembly, but once assembled, collagen fibres shield Fn fibres from being stretched by cellular traction forces. Thus, in addition to the well-recognized, force-regulated, cell-matrix interactions, forces also tune the interactions between different structural ECM components.
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100
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Jouett NP, Watenpaugh DE, Dunlap ME, Smith ML. Interactive effects of hypoxia, hypercapnia and lung volume on sympathetic nerve activity in humans. Exp Physiol 2015; 100:1018-29. [DOI: 10.1113/ep085092] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 06/24/2015] [Indexed: 01/11/2023]
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