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Storlund RL, Rosen DAS, Haulena M, Sanatani S, Vander Zaag J, Trites AW. Ultrasound images of the ascending aorta of anesthetized northern fur seals and Steller sea lions confirm that the aortic bulb maintains continuous blood flow. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2024; 341:458-469. [PMID: 38409932 DOI: 10.1002/jez.2799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 02/02/2024] [Accepted: 02/09/2024] [Indexed: 02/28/2024]
Abstract
The increased size and enhanced compliance of the aortic bulb-the enlargement of the ascending aorta-are believed to maintain blood flow in pinnipeds during extended periods of diastole induced by diving bradycardia. The aortic bulb has been described ex vivo in several species of pinnipeds, but in vivo measurements are needed to investigate the relationship between structure and function. We obtained ultrasound images using electrocardiogram-gated transesophageal echocardiography during anesthesia and after atropine administration to assess the relationship between aortic bulb anatomy and cardiac function (heart rate, stroke volume, cardiac output) in northern fur seals (Callorhinus ursinus) and Steller sea lions (Eumetopias jubatus). We observed that the aortic bulb in northern fur seals and Steller sea lions expands during systole and recoils over the entire diastolic period indicating that blood flow is maintained throughout the entire cardiac cycle as expected. The stroke volumes we measured in the fur seals and sea lions fit the values predicted based on body size in mammals and did not change with increased heart rates, suggesting that greater stroke volumes are not needed for aortic bulb function. Overall, our results suggest that peripheral vasoconstriction during diving is sufficient to modulate the volume of blood in the aortic bulb to ensure that flow lasts over the entire diastolic period. These results indicate that the shift of blood into the aortic bulb of pinnipeds is a fundamental mechanism caused by vasoconstriction while diving, highlighting the importance of this unique anatomical adaptation.
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Affiliation(s)
- Rhea L Storlund
- Marine Mammal Research Unit, Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - David A S Rosen
- Marine Mammal Research Unit, Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Aquarium, Vancouver, British Columbia, Canada
| | | | - Shubhayan Sanatani
- Division of Cardiology, British Columbia Children's Hospital, Vancouver, British Columbia, Canada
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jessica Vander Zaag
- Division of Cardiology, British Columbia Children's Hospital, Vancouver, British Columbia, Canada
| | - Andrew W Trites
- Marine Mammal Research Unit, Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
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2
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Pearson AB, Hückstädt LA, Kinsey ST, Schmitt TL, Robeck TR, St Leger J, Ponganis PJ, Tift MS. Relationship between red blood cell lifespan and endogenous carbon monoxide in the common bottlenose dolphin and beluga. Am J Physiol Regul Integr Comp Physiol 2024; 326:R134-R146. [PMID: 37982188 DOI: 10.1152/ajpregu.00172.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/17/2023] [Accepted: 11/15/2023] [Indexed: 11/21/2023]
Abstract
Certain deep-diving marine mammals [i.e., northern elephant seal (Mirounga angustirostris), Weddell seal (Leptonychotes weddellii)] have blood carbon monoxide (CO) levels that are comparable with those of chronic cigarette smokers. Most CO produced in humans is a byproduct of heme degradation, which is released when red blood cells (RBCs) are destroyed. Elevated CO can occur in humans when RBC lifespan decreases. The contribution of RBC turnover to CO concentrations in marine mammals is unknown. Here, we report the first RBC lifespans in two healthy marine mammal species with different diving capacities and heme stores, the shallow-diving bottlenose dolphin (Tursiops truncatus) and deep-diving beluga whale (Delphinapterus leucas), and we relate the lifespans to the levels of CO in blood and breath. The belugas, with high blood heme stores, had the longest mean RBC lifespan compared with humans and bottlenose dolphins. Both cetacean species were found to have three times higher blood CO content compared with humans. The estimated CO production rate from heme degradation indicates some marine mammals may have additional mechanisms for CO production, or delay CO removal from the body, potentially from long-duration breath-holds.NEW & NOTEWORTHY This is the first study to determine the red blood cell lifespan in a marine mammal species. High concentrations of carbon monoxide (CO) were found in the blood of bottlenose dolphins and in the blood and breath of belugas compared with healthy humans. Red blood cell turnover accounted for these high levels in bottlenose dolphins, but there may be alternative mechanisms of endogenous CO production that are contributing to the CO concentrations observed in belugas.
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Affiliation(s)
- Anna B Pearson
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, United States
| | - Luis A Hückstädt
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, United States
- Centre for Ecology and Conservation, University of Exeter, Penryn, United Kingdom
| | - Stephen T Kinsey
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, United States
| | - Todd L Schmitt
- SeaWorld Parks and Entertainment, San Diego, California, United States
| | - Todd R Robeck
- SeaWorld Parks and Entertainment, San Diego, California, United States
| | - Judy St Leger
- Cornell University College of Veterinary Medicine, Cornell University, Ithaca, New York, United States
| | - Paul J Ponganis
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States
| | - Michael S Tift
- Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, North Carolina, United States
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3
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Udroiu I. A Simplified Method for Calculating Surface Area of Mammalian Erythrocytes. Methods Protoc 2024; 7:11. [PMID: 38392685 PMCID: PMC10891711 DOI: 10.3390/mps7010011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 01/05/2024] [Accepted: 01/22/2024] [Indexed: 02/24/2024] Open
Abstract
Knowledge of the geometric quantities of the erythrocyte is useful in several physiological studies, both for zoologists and veterinarians. While the diameter and volume (MCV) are easily obtained from observations of blood smears and complete blood count, respectively, the thickness and surface area are instead much more difficult to measure. The precise description of the erythrocyte geometry is given by the equation of the oval of Cassini, but the formulas deriving from it are very complex, comprising elliptic integrals. In this article, three solids are proposed as models approximating the erythrocyte: sphere, cylinder and a spheroid with concave caps. The volumes and surface areas obtained with these models are compared to those effectively measured. The spheroid with concave caps gives the best approximation and can be used as a simple model to determine the erythrocyte surface area. With this model, a simple method that allows one to estimate the surface area by knowing only the diameter and MCV is proposed.
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Affiliation(s)
- Ion Udroiu
- Dipartimento di Scienze, Università degli Studi "Roma Tre", 00146 Rome, Italy
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4
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He RS, De Ruiter S, Westover T, Somarelli JA, Blawas AM, Dayanidhi DL, Singh A, Steves B, Driesinga S, Halsey LG, Fahlman A. Allometric scaling of metabolic rate and cardiorespiratory variables in aquatic and terrestrial mammals. Physiol Rep 2023; 11:e15698. [PMID: 37271741 PMCID: PMC10239733 DOI: 10.14814/phy2.15698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 04/21/2023] [Accepted: 04/23/2023] [Indexed: 06/06/2023] Open
Abstract
While basal metabolic rate (BMR) scales proportionally with body mass (Mb ), it remains unclear whether the relationship differs between mammals from aquatic and terrestrial habitats. We hypothesized that differences in BMR allometry would be reflected in similar differences in scaling of O2 delivery pathways through the cardiorespiratory system. We performed a comparative analysis of BMR across 63 mammalian species (20 aquatic, 43 terrestrial) with a Mb range from 10 kg to 5318 kg. Our results revealed elevated BMRs in small (>10 kg and <100 kg) aquatic mammals compared to small terrestrial mammals. The results demonstrated that minute ventilation, that is, tidal volume (VT )·breathing frequency (fR ), as well as cardiac output, that is, stroke volume·heart rate, do not differ between the two habitats. We found that the "aquatic breathing strategy", characterized by higher VT and lower fR resulting in a more effective gas exchange, and by elevated blood hemoglobin concentrations resulting in a higher volume of O2 for the same volume of blood, supported elevated metabolic requirements in aquatic mammals. The results from this study provide a possible explanation of how differences in gas exchange may serve energy demands in aquatic versus terrestrial mammals.
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Affiliation(s)
- Rebecca S. He
- Duke University Marine LaboratoryNicholas School of the EnvironmentBeaufortNorth CarolinaUSA
- Department of BiologyDuke UniversityDurhamNorth CarolinaUSA
| | - Stacy De Ruiter
- Department of Mathematics and StatisticsCalvin UniversityGrand RapidsMichiganUSA
| | - Tristan Westover
- Duke University Marine LaboratoryNicholas School of the EnvironmentBeaufortNorth CarolinaUSA
- Department of BiologyDuke UniversityDurhamNorth CarolinaUSA
| | - Jason A. Somarelli
- Department of MedicineDuke University Medical CenterDurhamNorth CarolinaUSA
| | - Ashley M. Blawas
- Duke University Marine LaboratoryNicholas School of the EnvironmentBeaufortNorth CarolinaUSA
- Department of MedicineDuke University Medical CenterDurhamNorth CarolinaUSA
| | - Divya L. Dayanidhi
- Department of MedicineDuke University Medical CenterDurhamNorth CarolinaUSA
| | - Ana Singh
- Department of Mathematics and StatisticsCalvin UniversityGrand RapidsMichiganUSA
| | - Benjamin Steves
- Department of Mathematics and StatisticsCalvin UniversityGrand RapidsMichiganUSA
| | - Samantha Driesinga
- Department of Mathematics and StatisticsCalvin UniversityGrand RapidsMichiganUSA
| | - Lewis G. Halsey
- School of Life and Health SciencesUniversity of RoehamptonLondonUK
| | - Andreas Fahlman
- Fundación Oceanogràfic de la Comunitat ValencianaValenciaSpain
- Kolmarden Wildlife ParkKolmardenSweden
- Linkoping University, IFMLinköpingSweden
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5
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Wilman B, Staniszewska M, Bełdowska M. Is the inhalation influence on the level of mercury and PAHs in the lungs of the baltic grey seal (Halichoerus grypusgrypus)? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 320:121083. [PMID: 36649880 DOI: 10.1016/j.envpol.2023.121083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
For many decades, mercury (Hg) has been recognized as one of the most dangerous environmental pollutants that negatively affects the ecosystem, including human health. Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic, toxic and potentially carcinogenic compounds. The process of respiration in addition to dietary intake is a significant source of these compounds to the human or marine mammalian body. Therefore, the aim of this study was to determine the sources of PAHs and labile forms of mercury in the lungs of dead seals found in the southern Baltic Sea. Of the PAHs: pyrene, fluoranthene and chrysene showed the highest concentrations. Considering the content of individual Hg fractions, the highest percentage was characterized by Hg labile 1b (related to organic matter). In a few specimens, deviations from the trend described above were observed: a higher proportion of Hg labile 1a (mainly halide-bound forms of mercury than the mean value which may indicate their origin from aerosols). Hg concentrations increased with seal age due to bioaccumulation and biomagnification of Hg from food; therefore, adsorption of atmospheric mercury on alveoli is probably of decreasing importance with seal age. Ratios obtained: FLA/PYR <1; B(a)A/CHR <1; FLA/(PYR + FLA) < 0.4 indicate a petrogenic source. In contrast, high correlations of B(a)A, FLA and PYR and CHR with Hg suggest a common source of PAHs and mercury - from food. Conversely, the presence of pyrogenic (combustion-derived) benzo(a)pyrene in the lungs of these mammals could indicate a respiratory route of entry. Mercury and PAHs in the lungs of the seals studied were mainly of trophic origin, but the results presented here make the hypothesis of an airborne influx of Hg and PAHs into the lungs from marine mammals plausible. This is of particular importance in juveniles (pups), who, at the initial stage of life, spend time on land and do not obtain food on their own.
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Affiliation(s)
- Bartłomiej Wilman
- Department of Marine Chemistry and Environmental Protection, Institute of Oceanography, University of Gdansk, Al. Marszałka J. Piłsudskiego 46, 81-378 Gdynia, Poland.
| | - Marta Staniszewska
- Department of Marine Chemistry and Environmental Protection, Institute of Oceanography, University of Gdansk, Al. Marszałka J. Piłsudskiego 46, 81-378 Gdynia, Poland
| | - Magdalena Bełdowska
- Department of Marine Chemistry and Environmental Protection, Institute of Oceanography, University of Gdansk, Al. Marszałka J. Piłsudskiego 46, 81-378 Gdynia, Poland
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6
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Comparative genomics provides insights into the aquatic adaptations of mammals. Proc Natl Acad Sci U S A 2021; 118:2106080118. [PMID: 34503999 PMCID: PMC8449357 DOI: 10.1073/pnas.2106080118] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2021] [Indexed: 12/30/2022] Open
Abstract
Divergent lineages can respond to common environmental factors through convergent processes involving shared genomic components or pathways, but the molecular mechanisms are poorly understood. Here, we provide genomic resources and insights into the evolution of mammalian lineages adapting to aquatic life. Our data suggest convergent evolution, for example, in association with thermoregulation through genes associated with a surface heat barrier (NFIA) and internal heat exchange (SEMA3E). Combined with the support of previous reports showing that the UCP1 locus has been lost in many marine mammals independently, our results suggest that the thermostatic strategy of marine mammals shifted from enhancing heat production to limiting heat loss. The ancestors of marine mammals once roamed the land and independently committed to an aquatic lifestyle. These macroevolutionary transitions have intrigued scientists for centuries. Here, we generated high-quality genome assemblies of 17 marine mammals (11 cetaceans and six pinnipeds), including eight assemblies at the chromosome level. Incorporating previously published data, we reconstructed the marine mammal phylogeny and population histories and identified numerous idiosyncratic and convergent genomic variations that possibly contributed to the transition from land to water in marine mammal lineages. Genes associated with the formation of blubber (NFIA), vascular development (SEMA3E), and heat production by brown adipose tissue (UCP1) had unique changes that may contribute to marine mammal thermoregulation. We also observed many lineage-specific changes in the marine mammals, including genes associated with deep diving and navigation. Our study advances understanding of the timing, pattern, and molecular changes associated with the evolution of mammalian lineages adapting to aquatic life.
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7
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HEMATOLOGY AND SERUM BIOCHEMISTRY OF HARBOR SEAL ( PHOCA VITULINA) PUPS AFTER REHABILITATION IN THE NETHERLANDS. J Zoo Wildl Med 2020; 50:1021-1025. [PMID: 31926541 DOI: 10.1638/2018-0098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/06/2019] [Indexed: 11/21/2022] Open
Abstract
Hematology and serum biochemistry profiles are used to evaluate the health status of animals ongoing rehabilitation. The aim of this project was to develop blood and biochemistry ranges for harbor seal pups (Phoca vitulina) after rehabilitation; thus, 22 different blood parameters in 60 animals were tested before release. The second goal was to test for differences due to sex, stranding location, body condition at admission, and presence or absence of umbilical cord. The alanine aminotransferase, ALT (or glutamate pyruvate transaminase, GPT), (ALT-GPT) differed significantly (P bq = 0.00851) between sexes. Lower leukocyte counts and higher liver enzyme values were the most remarkable findings when comparing the results of this study to other published data. This is the first study to report blood reference ranges for harbor seal pups in the Dutch Wadden Sea after rehabilitation.
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8
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Okhina AA, Rogachev AD, Yarovaya OI, Khvostov MV, Tolstikova TG, Pokrovsky AG, Khazanov VA, Salakhutdinov NF. Development and validation of an LC-MS/MS method for the quantitative analysis of the anti-influenza agent camphecene in rat plasma and its application to study the blood-to-plasma distribution of the agent. J Pharm Biomed Anal 2020; 180:113039. [DOI: 10.1016/j.jpba.2019.113039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/29/2019] [Accepted: 12/08/2019] [Indexed: 12/11/2022]
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9
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Fleischle CV, Sander PM, Wintrich T, Caspar KR. Hematological convergence between Mesozoic marine reptiles (Sauropterygia) and extant aquatic amniotes elucidates diving adaptations in plesiosaurs. PeerJ 2019; 7:e8022. [PMID: 31763069 PMCID: PMC6873879 DOI: 10.7717/peerj.8022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/10/2019] [Indexed: 12/15/2022] Open
Abstract
Plesiosaurs are a prominent group of Mesozoic marine reptiles, belonging to the more inclusive clades Pistosauroidea and Sauropterygia. In the Middle Triassic, the early pistosauroid ancestors of plesiosaurs left their ancestral coastal habitats and increasingly adapted to a life in the open ocean. This ecological shift was accompanied by profound changes in locomotion, sensory ecology and metabolism. However, investigations of physiological adaptations on the cellular level related to the pelagic lifestyle are lacking so far. Using vascular canal diameter, derived from osteohistological thin-sections, we show that inferred red blood cell size significantly increases in pistosauroids compared to more basal sauropterygians. This change appears to have occurred in conjunction with the dispersal to open marine environments, with cell size remaining consistently large in plesiosaurs. Enlarged red blood cells likely represent an adaptation of plesiosaurs repeated deep dives in the pelagic habitat and mirror conditions found in extant marine mammals and birds. Our results emphasize physiological aspects of adaptive convergence among fossil and extant marine amniotes and add to our current understanding of plesiosaur evolution.
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Affiliation(s)
- Corinna V. Fleischle
- Section Paleontology, Institute of Geosciences, University of Bonn, Bonn, Germany
| | - P. Martin Sander
- Section Paleontology, Institute of Geosciences, University of Bonn, Bonn, Germany
- Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, CA, USA
| | - Tanja Wintrich
- Section Paleontology, Institute of Geosciences, University of Bonn, Bonn, Germany
- Institute of Anatomy, University of Bonn, Bonn, Germany
| | - Kai R. Caspar
- Section Paleontology, Institute of Geosciences, University of Bonn, Bonn, Germany
- Department of General Zoology, Faculty of Biology, University of Duisburg-Essen, Essen, Germany
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10
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Nabi G, Robeck TR, Hao Y, Wang D. Hematologic and Biochemical Reference Interval Development and the Effect of Age, Sex, Season, and Location on Hematologic Analyte Concentrations in Critically Endangered Yangtze Finless Porpoise ( Neophocaena asiaeorientalis ssp. asiaeorientalis). Front Physiol 2019; 10:792. [PMID: 31354505 PMCID: PMC6637261 DOI: 10.3389/fphys.2019.00792] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/05/2019] [Indexed: 11/13/2022] Open
Abstract
In this study, references intervals for 49 clinicopathological parameters were established for the critically endangered Yangtze finless porpoise (YFP) (Neophocaena phocaenoides asiaorientalis). Both from the wild (Poyang Lake) and seminatural (Tian-E-Zhou Oxbow) populations, individual blood samples from 188 animals were collected from 2009 to 2017 and from 2002 to 2015, respectively. For reference interval determination, we used a non-parametric bootstrap-based procedure to determine the 95th percentiles and the associated 90% confidence interval for each analyte. Our results indicated a need to partition the analyte concentrations by sex, age group, or pregnancy; however, we did not find a need to partition results by location. We then used a linear mixed model to determine if evidence existed for mean differences between location with sex and season as covariates and age group as the clustered random variable on mean hematological parameters in the YFP. We found that 88% of the analytes were significantly different between locations. Within the covariates, sex and season showed 31 and 69% significant difference in mean distributions, respectively. Additionally, age group provided a significant source of variation in 25% of the analytes. In summary, our finding suggests that analytes should be grouped according to sex, age, and reproductive status (non-pregnant and non-lactating, pregnant and lactating). Furthermore, we have provided the first set of reference intervals for 49 clinicopathological parameters that could provide guidelines for the initial evaluation of individuals during health assessments.
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Affiliation(s)
- Ghulam Nabi
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Todd R. Robeck
- SeaWorld Parks & Entertainment, Orlando, FL, United States
| | - Yujiang Hao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Ding Wang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
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11
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Vega JL. Ictal Mammalian Dive Response: A Likely Cause of Sudden Unexpected Death in Epilepsy. Front Neurol 2018; 9:677. [PMID: 30174646 PMCID: PMC6108060 DOI: 10.3389/fneur.2018.00677] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 07/27/2018] [Indexed: 12/22/2022] Open
Abstract
Even though sudden unexpected death in epilepsy (SUDEP) takes the lives of thousands of otherwise healthy epilepsy patients every year, the physiopathology associated with this condition remains unexplained. This article explores important parallels, which exist between the clinical observations and pathological responses associated with SUDEP, and the pathological responses that can develop when a set of autonomic reflexes known as the mammalian dive response (MDR) is deployed. Mostly unknown to physicians, this evolutionarily conserved physiological response to prolonged apnea economizes oxygen for preferential use by the brain. However, the drastic cardiovascular adjustments required for its execution, which include severe bradycardia and the sequestration of a significant portion of the total blood volume inside the cardiopulmonary vasculature, can result in many of the same pathological responses associated with SUDEP. Thus, this article advances the hypothesis that prolonged apneic generalized tonic clonic seizures induce augmented forms of the MDR, which, in the most severe cases, cause SUDEP.
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Affiliation(s)
- Jose L Vega
- Department of Neurosciences and Stroke, Novant Health, Forsyth Medical Center, Winston-Salem, NC, United States.,TeleNeurologia SAS, Medellin, Colombia
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12
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Froelich JJ, Ray U, Monkhorst J, Marwick TH, Hardikar A, Harle R, Carr MW. Evaluation of hemolysis in microcatheter directed blood infusion at different flow rates for transarterial salvage reperfusion: In-vitro study. Biorheology 2015; 52:279-91. [DOI: 10.3233/bir-15074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Jens J. Froelich
- Department of Medical Imaging, Royal Hobart Hospital, Hobart, TAS, Australia
| | - Udayan Ray
- Department of Pathology, Royal Hobart Hospital, Hobart, Australia
| | - Jessica Monkhorst
- Department of Medical Imaging, Royal Hobart Hospital, Hobart, TAS, Australia
| | - Thomas H. Marwick
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Ashutosh Hardikar
- Department of Cardiothoracic Surgery, Royal Hobart Hospital, Hobart, Australia
| | - Robin Harle
- Department of Medical Imaging, Royal Hobart Hospital, Hobart, TAS, Australia
| | - Michael W. Carr
- Department of Medical Imaging, Royal Hobart Hospital, Hobart, TAS, Australia
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13
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Kar S, Dash M, Maiti TK, Chakraborty S. Effect of hematocrit on blood dynamics on a compact disc platform. Analyst 2015; 140:1432-7. [PMID: 25619412 DOI: 10.1039/c4an02020k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We investigate blood flow dynamics on a rotationally actuated lab-on-a-compact disk (LOCD) platform, as a function of the hematocrit level of the blood sample. In particular, we emphasize the resultant implications on the critical fluidic parameters, such as on burst frequency and volumetric flow rate. Our results can be utilized as a characteristic guideline to predict the hematological parameters of a given small amount of blood sample from the observed flow characteristics, and can give rise to a new paradigm of medical diagnostics driven by interactions between blood rheology and rotational forces on an inexpensive platform, with minimal sample consumption.
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Affiliation(s)
- Shantimoy Kar
- Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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14
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Quantitative characterization of endothelial cell morphologies depending on shear stress in different blood vessels of domestic pigs using a focused ion beam and high resolution scanning electron microscopy (FIB-SEM). Tissue Cell 2014; 47:205-12. [PMID: 25622890 DOI: 10.1016/j.tice.2014.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 12/12/2014] [Accepted: 12/19/2014] [Indexed: 11/23/2022]
Abstract
Microstructured surfaces mimicking the endothelial cell (EC) morphology is a new approach to improve the blood compatibility of synthetic vascular grafts. The ECs are capable of changing their shapes depending on different shear conditions. However, the quantitative correlation between EC morphology and shear stress has not yet been investigated statistically. The aim of this study was to quantitatively investigate the morphology of ECs in dependence on the shear stress. Blood flow rates in different types of natural blood vessels (carotid, renal, hepatic and iliac arteries) originated from domestic pigs were first measured in vivo to calculate the shear stresses. The EC morphologies were quantitatively characterized ex vivo by imaging with high resolution scanning electron microscopy (SEM) and cross-sectioning of the cells using a state-of-the-art focused ion beam (FIB). The relationships between EC geometrical parameters and shear stress were statistically analyzed and found to be exponential. ECs under high shear stress conditions had a longer length and narrower width, i.e. a higher aspect ratio, while the cell height was smaller compared to low shear conditions. Based on these results, suitable and valid geometrical parameters of microstructures mimicking EC can be derived for various shear conditions in synthetic vascular grafts to optimize blood compatibility.
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15
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Panneton WM. The mammalian diving response: an enigmatic reflex to preserve life? Physiology (Bethesda) 2014; 28:284-97. [PMID: 23997188 DOI: 10.1152/physiol.00020.2013] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mammalian diving response is a remarkable behavior that overrides basic homeostatic reflexes. It is most studied in large aquatic mammals but is seen in all vertebrates. Pelagic mammals have developed several physiological adaptations to conserve intrinsic oxygen stores, but the apnea, bradycardia, and vasoconstriction is shared with those terrestrial and is neurally mediated. The adaptations of aquatic mammals are reviewed here as well as the neural control of cardiorespiratory physiology during diving in rodents.
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Affiliation(s)
- W Michael Panneton
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, MO, USA.
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