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1.
Proc Natl Acad Sci U S A ; 115(12): 3072-3077, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29483242

RESUMO

The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals' movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyze a global dataset of ∼2.8 million locations from >2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared with more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal microhabitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise, and declining oxygen content.


Assuntos
Migração Animal , Bases de Dados Factuais , Oceanos e Mares , Vertebrados , Animais , Ecossistema
2.
J Exp Biol ; 213(5): 740-8, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20154189

RESUMO

In diving animals, skeletal muscle adaptations to extend underwater time despite selective vasoconstriction include elevated myoglobin (Mb) concentrations, high acid buffering ability (beta) and high aerobic and anaerobic enzyme activities. However, because cardiac muscle is perfused during dives, it may rely less heavily on Mb, beta and anaerobic pathways to support contractile activity. In addition, because cardiac tissue must sustain contractile activity even before birth, it may be more physiologically mature at birth and/or develop faster than skeletal muscles. To test these hypotheses, we measured Mb levels, beta and the activities of citrate synthase (CS), beta-hydroxyacyl-CoA dehydrogenase (HOAD) and lactate dehydrogenase (LDH) in cardiac and skeletal muscle samples from 72 harp and hooded seals, ranging in age from fetuses to adults. Results indicate that in adults cardiac muscle had lower Mb levels (14.7%), beta (55.5%) and LDH activity (36.2%) but higher CS (459.6%) and HOAD (371.3%) activities (all P<0.05) than skeletal muscle. In addition, while the cardiac muscle of young seals had significantly lower [Mb] (44.7%) beta (80.7%) and LDH activity (89.5%) than adults (all P<0.05), it was relatively more mature at birth and weaning than skeletal muscle. These patterns are similar to those in terrestrial species, suggesting that seal hearts do not exhibit unique adaptations to the challenges of an aquatic existence.


Assuntos
Caniformia/crescimento & desenvolvimento , Caniformia/metabolismo , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Focas Verdadeiras/crescimento & desenvolvimento , Focas Verdadeiras/metabolismo , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Aerobiose , Envelhecimento/metabolismo , Anaerobiose , Animais , Peso Corporal/fisiologia , Canadá , Locomoção , Músculo Esquelético/enzimologia , Músculo Esquelético/crescimento & desenvolvimento , Miocárdio/enzimologia , Mioglobina/metabolismo , Especificidade de Órgãos
3.
Int J Clin Pract ; 62(5): 701-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18341566

RESUMO

OBJECTIVE: To determine the relationship between insulin resistance (IR) and atheroma burden in Pakistanis. METHODS: A prospective case-control study of 400 patients selected for the presence/absence of angiographic disease. Coronary atheroma burden was quantified and IR and cardiovascular risk factors were measured. RESULTS: The patients were divided into two groups by QuickI score. Waist circumference (90 +/- 10 vs. 90 +/- 9 cm; p = 0.7) was similar but the groups differed in body mass index (26.5 +/- 3.7 vs. 24.2 +/- 3.5 kg/m(2); p < 0.001) and waist:hip ratio (0.94 +/- 0.09 vs. 0.90 +/- 0.06; p < 0.001). Lipid parameters showed similar high-density lipoprotein cholesterol (HDL-C) (0.77 +/- 0.23 vs. 0.82 +/- 0.22 mmol/l; p = 0.1) differences in triglycerides [1.32 (0.08-3.98) vs. 1.12 (0.37-3.61) mmol/l; p = 0.01], but no difference in low-density lipoprotein cholesterol (LDL-C) (2.75 +/- 1.00 vs. 2.90 +/- 0.94 mmol/l; p = 0.14). In insulin-resistant patients C-reactive protein (CRP) [6.8 (0.3-175.1) vs. 3.9 (0.2-57.9) mg/l: p < 0.001], sialic acid (82 +/- 14 vs. 77 +/- 15 mg/l; p < 0.001) aspartate transaminase [24 (7-171) vs. 21 (7-83) IU/l; p < 0.001] and gamma-glutamyl transferase [27 (8-482) vs. 21 (7-168) IU/l; p = 0.005] levels were increased. In insulin-resistant patients (n = 187), coronary artery disease (CAD) burden correlated (r = 0.55) with age (beta = 1.62; p < 0.001), HDL-C (beta = -53.2; p < 0.001), lipoprotein (a) (beta = 11.4; p = 0.007), smoking (beta = 7.98; p = 0.004), CRP (beta = 6.06; p = 0.03) and QuickI index (beta = -146; p = 0.04). In contrast in insulin-sensitive patients (n = 178) CAD burden (r = 0.46) correlated with LDL-C (beta = 10.0; p = 0.02), CRP (beta = 7.13; p = 0.03), HDL-C (beta = -38.1; p = 0.03), and weakly with age (beta = 0.73; p = 0.07) and smoking (beta = 5.52; p = 0.09). CONCLUSIONS: Indian Asians show a dichotomous insulin-resistance phenotype. Atheroma is associated with low HDL-C and inflammation associated in all but LDL-C is a factor in the insulin sensitive in contrast to age and extent of IR in the insulin resistant.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Resistência à Insulina , Adulto , Aterosclerose/fisiopatologia , Constituição Corporal , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Fatores de Risco
4.
Sci Rep ; 7: 45127, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28338047

RESUMO

Estimating animal populations is critical for wildlife management. Aerial surveys are used for generating population estimates, but can be hampered by cost, logistical complexity, and human risk. Additionally, human counts of organisms in aerial imagery can be tedious and subjective. Automated approaches show promise, but can be constrained by long setup times and difficulty discriminating animals in aggregations. We combine unmanned aircraft systems (UAS), thermal imagery and computer vision to improve traditional wildlife survey methods. During spring 2015, we flew fixed-wing UAS equipped with thermal sensors, imaging two grey seal (Halichoerus grypus) breeding colonies in eastern Canada. Human analysts counted and classified individual seals in imagery manually. Concurrently, an automated classification and detection algorithm discriminated seals based upon temperature, size, and shape of thermal signatures. Automated counts were within 95-98% of human estimates; at Saddle Island, the model estimated 894 seals compared to analyst counts of 913, and at Hay Island estimated 2188 seals compared to analysts' 2311. The algorithm improves upon shortcomings of computer vision by effectively recognizing seals in aggregations while keeping model setup time minimal. Our study illustrates how UAS, thermal imagery, and automated detection can be combined to efficiently collect population data critical to wildlife management.


Assuntos
Tecnologia de Sensoriamento Remoto/métodos , Focas Verdadeiras/fisiologia , Termografia/métodos , Aeronaves , Algoritmos , Animais , Automação/instrumentação , Automação/métodos , Biomassa , Tecnologia de Sensoriamento Remoto/instrumentação , Termografia/instrumentação
5.
Physiol Biochem Zool ; 88(2): 167-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25730272

RESUMO

In adult marine mammals, muscles can sustain aerobic metabolism during dives in part because they contain large oxygen (O2) stores and metabolic rates are low. However, young pups have significantly lower tissue O2 stores and much higher mass-specific metabolic rates. To investigate how these differences may influence muscle function during dives, we measured the activities of enzymes involved in aerobic and anaerobic metabolic pathways (citrate synthase [CS], ß-hydroxyacyl-coenzyme A dehydrogenase [HOAD], lactate dehydrogenase [LDH]) and the LDH isoform profile in six muscles from 41 harp (Pagophilus groenlandicus) and 30 hooded (Cystophora cristata) seals ranging in age from fetal to adult. All neonatal muscles had significantly higher absolute but lower metabolically scaled CS and HOAD activities than adults (∼ 70% and ∼ 85% lower, respectively). Developmental increases in LDH activity lagged that of aerobic enzymes and were not accompanied by changes in isozyme profile, suggesting that changes in enzyme concentration rather than structure determine activity levels. Biochemical maturation proceeded faster in the major locomotory muscles. In combination, findings suggest that pup muscles are unable to support strenuous aerobic exercise or rely heavily on anaerobic metabolism during early diving activities and that pups' high mass-specific metabolic rates may play a key role in limiting the ability of their muscles to support underwater foraging.


Assuntos
Mergulho/fisiologia , Músculo Esquelético/metabolismo , Oxigênio/metabolismo , Focas Verdadeiras/metabolismo , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Envelhecimento/fisiologia , Animais , Animais Recém-Nascidos , Citrato (si)-Sintase/metabolismo , Feminino , Feto/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Desenvolvimento Muscular , Músculo Esquelético/enzimologia , Músculo Esquelético/crescimento & desenvolvimento , Focas Verdadeiras/crescimento & desenvolvimento
6.
Eur J Hum Genet ; 8(8): 649-51, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10951529

RESUMO

Refsum's disease (MIM 266500) is a recessive disorder characterised by defective peroxisomal alpha-oxidation of phytanic acid. A Refsum's disease gene, phytanoyl-CoA hydroxylase (PAHX), has been localised to chromosome 10p13 between the markers D10S226-D10S223. This study investigated whether all cases of Refsum's disease were linked with chromosome 10p13. Eight genetically informative families comprising 92 individuals including 17 living patients with a Refsum's disease phenotype and initial plasma phytanic acid > 200 micromol/L were recruited. Linkage to the 10pter-10p11.2 region was investigated using a panel of eight dinucleotide repeat markers. Linkage analysis of this phenotypically identical cohort suggested that Refsum's disease was genetically heterogeneous (Zmax = 5.28, alpha = 0.45). Two subgroups were identified. One group of four families with eight affected individuals had a maximum multipoint lod score for linkage of 3.89 in the region D10S547 to D10S191, whilst in another three families with nine affected individuals linkage to this region was definitely excluded. Our results show that Refsum's disease is genetically heterogeneous, with up to 55% of cases not being linked to the PAHX gene locus at D10S547 to D10S223. This suggests that Refsum's disease, in common with other peroxisomal 'diseases', may be more accurately described as a heterogeneous syndrome.


Assuntos
Cromossomos Humanos Par 10/genética , Heterogeneidade Genética , Oxigenases de Função Mista/genética , Doença de Refsum/genética , Mapeamento Cromossômico , Consanguinidade , Feminino , Genes Recessivos , Ligação Genética , Humanos , Escore Lod , Masculino , Repetições de Microssatélites , Linhagem , Doença de Refsum/enzimologia
7.
J Hum Hypertens ; 14(9): 561-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10980587

RESUMO

Sodium-lithium countertransport kinetics were measured in 87 patients (50 male; 37 female) with heterozygous familial hypercholesterolaemia (FH) and a group of 38 age range and sex-distribution matched controls. Basic clinical data including basic anthropometry, blood pressure were obtained and blood was taken for detailed lipid biochemistry, glucose and insulin measurement. Patients with FH had elevated total cholesterol, low-density lipoprotein (LDL)-cholesterol and apolipoprotein B concentrations compared to controls. The activity and log transformed maximal velocity (Vmax) of the sodium-lithium countertransporter unlike the affinity (Km) were reduced in patients with FH compared to controls (geometric means 0.172 vs 0.217 mmol Li+/L.RBC.hr; P = 0.02; 0.237 vs. 0.317 mmol Li+/L.RBC.hr; P = 0.009 respectively). In multiple regression analysis, log normalised SLC activity correlated weakly with log triglyceride (beta = 0.225; P = 0.06) and cholesterol (beta = -0.112 P = 0.06). Log Vmax correlated with log triglyceride (beta = 0.307; P = 0.02), and high-density lipoprotein (HDL) (beta = 0.74; P = 0.03) whilst Km correlated with HDL (beta = 1.73; P<0.001) and apoAI (beta = -1.76; P = 0.0048), LDL (beta = -0.14; P = 0.05), and creatine kinase (beta = 0.003; P = 0.01). Cholesterol and triglyceride concentrations rather than insulin resistance seem to be the key features affecting the environmental alteration of sodium lithium countertransporter Vmax in patients with familial hypercholesterolaemia.


Assuntos
Antiporters/metabolismo , Hiperlipoproteinemia Tipo II/metabolismo , Lipídeos/sangue , Adulto , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Valores de Referência , Triglicerídeos/sangue
8.
Sci Total Environ ; 243-244: 243-62, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10635597

RESUMO

Blubber samples from harbour (Phoca vitulina) and grey seals (Halichoerus grypus) captured in the St Lawrence Estuary were analysed for PCBs and OC pesticides. Concentrations of sigma PCB, sigma DDT, sigma CHLOR and mirex were higher in harbour than in grey seals, while sigma HCH and HCB were similar in the two species. Age vs. concentration plots showed that sigma PCB, sigma DDT and sigma CHLOR concentrations increased with age in males, but plateaued at sexual maturity in females. Concentrations of sigma HCH decreased and mirex increased with age for post-weaning animals, regardless of gender. HCB did not show age-related trends. PCB congener and OC pesticide patterns varied within harbour seals (based on gender and maturity) and between harbour and grey seals. PCB and OC concentrations in harbour seals were lower than those seen in a sample of significantly older beluga whales. Both species remain in the Estuary year-round. PCB and OC pesticide concentrations were higher in resident harbour seals than in either grey or harp seals that visit the Estuary seasonally. PCB and OC pesticide concentrations in harbour seals from the Estuary were generally higher than in harbour seals from other regions of North America. They were comparable to, or higher than those from the NE Atlantic Ocean and the North Sea, and lower than those from the Wadden and Baltic Seas.


Assuntos
Tecido Adiposo/química , Inseticidas/farmacocinética , Bifenilos Policlorados/farmacocinética , Focas Verdadeiras , Poluição Química da Água , Tecido Adiposo/citologia , Tecido Adiposo/crescimento & desenvolvimento , Envelhecimento , Animais , Biópsia , Canadá , Feminino , Água Doce , Inseticidas/análise , Masculino , Bifenilos Policlorados/análise , Água do Mar , Fatores Sexuais , Maturidade Sexual
9.
Environ Pollut ; 111(1): 29-43, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11202713

RESUMO

Levels of tris (4-chlorophenyl) methanol (TCPM) and its presumed precursor tris (4-chlorophenyl) methane (TCPMe) are reported in marine mammals from the Estuary and Gulf of St. Lawrence, Canada. These compounds were measured in blubber samples of seals and whales using ion trap mass spectrometry (MS/MS) detection. Detectable concentrations of both TCPM and TCPMe were observed in all of the samples analysed. Concentrations of these compounds varied with species ranging from 1.7 to 153 and from 1.3 to 50.6 ng/g lipid wt. for TCPM and TCPMe, respectively. TCPM was from 1.3 to 10 times more concentrated than TCPMe. The highest levels of both TCPM and TCPMe were observed in adult male beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary, while adult female beluga whales from the same area showed levels similar to those in the seals examined. Among the four seal species investigated, TCPM and TCPMe levels were the highest in grey (Halichoerus grypus) and hooded (Cystophora cristata) seals, and lowest in harp seals (Phoca groenlandica). Intermediate levels were found in harbour seals (Phoca vitulina); however, their concentrations might be underestimated considering the younger mean age of these animals. Ratios of both 4,4'-DDE/sigma DDT and TCPM/sigma TCP were very similar between animals from the same species. Strong correlations between sigma TCP and sigma DDT were also observed for each species of mammals, most likely indicating that both sigma TCP and sigma DDT are bioaccumulated in marine mammals. The relationships between sigma DDT and sigma TCP also demonstrate that sigma TCP are less bioaccumulated than sigma DDT by the marine mammal species examined.


Assuntos
Tecido Adiposo/química , Focas Verdadeiras , Compostos de Tritil/análise , Poluentes Químicos da Água/análise , Baleias , Animais , Monitoramento Ambiental , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Quebeque
10.
Sci Total Environ ; 302(1-3): 145-55, 2003 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-12526905

RESUMO

Phocid seals have lipid rich milk, which is known to serve as a transfer medium through which persistent organic pollutants (POPs) move from mother to offspring during lactation. However, knowledge on this generational transfer of different POPs and the partitioning of these compounds in maternal and offspring tissues over the course of the lactation are limited. In this study we examined the qualitative and quantitative partitioning of a range of chlorinated POPs in maternal blubber, blood and milk as well as in pup blubber, collected early in the lactation period and late in the lactation period. In the lactating female, the high-chlorinated and hydrophobic compounds were passed less efficiently into the milk than the low-chlorinated compounds and more water-soluble compounds. Significantly, lower maternal blood concentrations than in maternal blubber biopsies suggest a stratification of POP concentrations in the blubber column of lactating female and lower concentrations in the metabolic active inner layers. Over the course of lactation, there was a significant increase in maternal blood and milk concentrations of POPs as opposed to no change in maternal blubber biopsy concentrations. This was most apparent for the hydrophobic and high-chlorinated compounds. The most likely explanation for this is that the metabolic active inner blubber layer, from which the milk lipids are derived from, is in steady state with the circulatory system, while the outer layers are more static and only slowly respond to changes in concentrations elsewhere in the body. The concentrations of the high-chlorinated and hydrophobic compounds were substantially lower in pup blubber than in maternal blubber. This probably relates the combined effect of these compounds stratification in maternal blubber and their slow transfer into the milk. The present study shows that the more hydrophobic and high-chlorinated compounds come to steady state less quickly in the different tissues than the more water-soluble and low-chlorinated compounds in the lactating female and her offspring. This has implications for which matrices to choose when sampling for assessing the toxicological risk of POPs in seals.


Assuntos
Tecido Adiposo/química , Hidrocarbonetos Clorados , Inseticidas/farmacocinética , Lactação , Focas Verdadeiras , Animais , Animais Recém-Nascidos , Biópsia , Feminino , Inseticidas/análise , Medição de Risco , Distribuição Tecidual
11.
AANA J ; 60(3): 282-6, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1632156

RESUMO

Many physicians, Certified Registered Nurse Anesthetists (CRNAs), and registered nurses have the clinical impression that either morphine sulfate or meperidine hydrochloride is a better drug to control postoperative pain. In this study, we evaluated pain relief and side effects for these two drugs to assess their potential differences. CRNAs conducted a structured interview of 500 female patients 24 hours after major gynecologic, urologic, or breast surgery. Patients' responses on 4-point scales of none, mild, moderate, and severe were collected for pain intensity, degree of nausea, severity of vomiting and itchiness, and degree of sedation experienced since the operation. There were 91 patients who received morphine patient-controlled analgesia (PCA) and 409 patients administered meperidine PCA. No statistically significant differences for pain intensity, degree of nausea, severity and incidence of vomiting, or degree of sedation were found. However, a significant difference was found in the incidence rates of mild itchiness, which occurred more frequently in the morphine PCA group (P less than .001). Patients vomited more often after vaginal hysterectomy than patients having laparotomy, major oncology, or tuboplasty surgeries (P less than .05), and vaginal repair patients reported more vomiting than patients having major oncology or tuboplasty surgeries. Clinical impressions that either morphine or meperidine should be the preferred treatment for patients following gynecologic operations was not found by a 24-hour review of 500 patients for pain relief and side effects. Although mild itchiness occurred more frequently in the morphine PCA group, treatment was rarely necessary.


Assuntos
Analgesia Controlada pelo Paciente/efeitos adversos , Meperidina/administração & dosagem , Morfina/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Adulto , Idoso , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Pesquisa em Avaliação de Enfermagem , Prurido/induzido quimicamente , Vômito/induzido quimicamente
12.
Nurs Manage ; 24(6): 28-30, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8510853

RESUMO

Prior to a JCAHO accreditation visit, Southeast Georgia Regional Medical Center implemented a program for improved prevention and treatment of nosocomial pressure ulcers. Forms were developed for monitoring skin integrity and therapy beds were tried from a vendor, which also provided a computerized assessment tool. Results included 15 percent pressure ulcer prevention in addition to enhanced collaborative nursing practice.


Assuntos
Serviço Hospitalar de Enfermagem/normas , Úlcera por Pressão/enfermagem , Garantia da Qualidade dos Cuidados de Saúde , Infecção Hospitalar/enfermagem , Infecção Hospitalar/prevenção & controle , Georgia , Humanos , Joint Commission on Accreditation of Healthcare Organizations , Avaliação em Enfermagem , Úlcera por Pressão/prevenção & controle , Projetos de Pesquisa
13.
J Comp Physiol B ; 183(8): 1075-88, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23743798

RESUMO

Phocid seals have been proposed as models for diabetes because they exhibit limited insulin response to glucose, high blood glucose and increasing insulin resistance when fasting. Liver glucose-6-phosphatase (G6Pase) catalyses the final step in glucose production and is central to glucose regulation in other animals. G6Pase comprises a translocase (SLC37A4) and a catalytic subunit (G6PC). G6PC and SLC37A4 expression and activity are normally regulated by nutritional state and glucostatic hormones, particularly insulin, and are elevated in diabetes. We tested the hypotheses that (1) grey seal G6PC and SLC37A4 cDNA and predicted protein sequences differ from other species' at functional sites, (2) relative G6Pase protein abundances are lower during feeding than fasting and (3) relative G6Pase protein abundances are related to insulin, insulin receptor phosphorylation and key metabolite levels. We show that G6PC and partial SLC37A4 cDNA sequences encode proteins sharing 82-95 % identity with other mammals. Seal G6PC contained no differences in sites responsible for activity, stability or subcellular location. Several substitutions in seal SLC37A4 were predicted to be tolerated with low probability, which could affect glucose production. Suckling pups had higher relative abundance of both subunits than healthy, postweaned fasting pups. Furthermore, relative G6PC abundance was negatively related to glucose levels. These findings contrast markedly with the response of relative hepatic G6Pase abundance to feeding, fasting, insulin, insulin sensitivity and key metabolites in other animals, and highlight the need to understand the regulation of enzymes involved in glucose control in phocids if these animals are to be informative models of diabetes.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Diabetes Mellitus/metabolismo , Glucose-6-Fosfatase/metabolismo , Insulina/metabolismo , Fígado/metabolismo , Focas Verdadeiras/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Primers do DNA/genética , DNA Complementar/genética , Modelos Animais de Doenças , Glucose/biossíntese , Glucose-6-Fosfatase/genética , Dados de Sequência Molecular , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Nova Escócia , Escócia , Focas Verdadeiras/genética , Focas Verdadeiras/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência , Especificidade da Espécie , Desmame
14.
J Comp Physiol B ; 180(5): 757-66, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20140678

RESUMO

Adult marine mammal muscles rely upon a suite of adaptations for sustained aerobic metabolism in the absence of freely available oxygen (O(2)). Although the importance of these adaptations for supporting aerobic diving patterns of adults is well understood, little is known about postnatal muscle development in young marine mammals. However, the typical pattern of vertebrate muscle development, and reduced tissue O(2) stores and diving ability of young marine mammals suggest that the physiological properties of harbor seal (Phoca vitulina) pup muscle will differ from those of adults. We examined myoglobin (Mb) concentration, and the activities of citrate synthase (CS), beta-hydroxyacyl coA dehydrogenase (HOAD), and lactate dehydrogenase (LDH) in muscle biopsies from harbor seal pups throughout the nursing period, and compared these biochemical parameters to those of adults. Pups had reduced O(2) carrying capacity ([Mb] 28-41% lower than adults) and reduced metabolically scaled catabolic enzyme activities (LDH/RMR 20-58% and CS/RMR 29-89% lower than adults), indicating that harbor seal pup muscles are biochemically immature at birth and weaning. This suggests that pup muscles do not have the ability to support either the aerobic or anaerobic performance of adult seals. This immaturity may contribute to the lower diving capacity and behavior in younger pups. In addition, the trends in myoglobin concentration and enzyme activity seen in this study appear to be developmental and/or exercise-driven responses that together work to produce the hypoxic endurance phenotype seen in adults, rather than allometric effects due to body size.


Assuntos
Mergulho/fisiologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/fisiologia , Phoca/fisiologia , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Envelhecimento/fisiologia , Animais , Animais Lactentes/crescimento & desenvolvimento , Animais Lactentes/metabolismo , Citrato (si)-Sintase/metabolismo , Feminino , L-Lactato Desidrogenase/metabolismo , Mioglobina/metabolismo , Phoca/crescimento & desenvolvimento , Desmame
16.
J Comp Physiol B ; 179(8): 985-96, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19565249

RESUMO

Pinnipeds rely on muscle oxygen stores to help support aerobic diving, therefore muscle maturation may influence the behavioral ecology of young pinnipeds. To investigate the pattern of muscle development, myoglobin concentration ([Mb]) and acid buffering ability (beta) was measured in ten muscles from 23 harp and 40 hooded seals of various ages. Adult [Mb] ranged from 28-97 to 35-104 mg g tissue(-1) in harp and hooded seals, respectively, with values increasing from the cervical, non-swimming muscles to the main swimming muscles of the lumbar region. Neonatal and weaned pup muscles exhibited lower (approximately 30% adult values) and less variable [Mb] across the body than adults. In contrast, adult beta showed little regional variation (60-90 slykes), while high pup values (approximately 75% adult values) indicate significant in utero development. These findings suggest that intra-uterine conditions are sufficiently hypoxic to stimulate prenatal beta development, but that [Mb] development requires additional postnatal signal such as exercise, and/or growth factors. However, because of limited development in both beta and [Mb] during the nursing period, pups are weaned with muscles with lower aerobic and anaerobic capacities than those of adults.


Assuntos
Equilíbrio Ácido-Base , Envelhecimento/fisiologia , Músculo Esquelético/crescimento & desenvolvimento , Mioglobina/metabolismo , Focas Verdadeiras/metabolismo , Animais , Animais Recém-Nascidos , Oceano Atlântico , Composição Corporal , Peso Corporal , Canadá , Mergulho/fisiologia , Feminino , Groenlândia , Masculino , Desenvolvimento Muscular , Músculo Esquelético/metabolismo , Especificidade de Órgãos , Focas Verdadeiras/crescimento & desenvolvimento , Especificidade da Espécie , Fatores de Tempo , Titulometria
17.
J Comp Physiol B ; 177(6): 687-700, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17576570

RESUMO

Pinnipeds rely primarily on oxygen stores in blood and muscles to support aerobic diving; therefore rapid development of body oxygen stores (TBO(2)) is crucial for pups to transition from nursing to independent foraging. Here, we investigate TBO(2) development in 45 harp (Pagophilus groenlandicus) and 46 hooded (Cystophora cristata) seals ranging in age from neonates to adult females. We found that hooded seal adults have the largest TBO(2) stores yet reported (89.5 ml kg(-1)), while harp seal adults have values more similar to other phocids (71.6 ml kg(-1)). In adults, large TBO(2) stores resulted from large blood volume (harp169, hood 194 ml kg(-1)) and high muscle Mb content (harp 86.0, hood 94.8 mg g(-1)). In contrast, pups of both species had significantly lower mass-specific TBO(2 )stores than adults, and stores declined rather than increased during the nursing period. This decline was due to a reduction in mass-specific blood volume and the absence of an increase in the low Mb levels (harp 21.0, hood 31.5 mg g(-1)). Comparisons with other phocid species suggests that the pattern of blood and muscle development in the pre- and post-natal periods varies with terrestrial period, and that muscle maturation rates may influence the length of the postweaning fast. However, final maturation of TBO(2) stores does not take place until after foraging begins.


Assuntos
Mergulho/fisiologia , Oxigênio/sangue , Oxigênio/metabolismo , Focas Verdadeiras/sangue , Focas Verdadeiras/fisiologia , Fatores Etários , Animais , Animais Recém-Nascidos/sangue , Animais Lactentes/sangue , Análise Química do Sangue/veterinária , Composição Corporal , Tamanho Corporal , Estudos Transversais , Índices de Eritrócitos/veterinária , Feminino , Testes Hematológicos/métodos , Testes Hematológicos/veterinária , Hemoglobinas/metabolismo , Músculo Esquelético/metabolismo , Mioglobina/metabolismo , Focas Verdadeiras/crescimento & desenvolvimento , Especificidade da Espécie
18.
Mol Ecol ; 16(8): 1639-48, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17402979

RESUMO

Two putative populations of hooded seals (Cystophora cristata) occur in the North Atlantic. The Greenland Sea population pup and breed on the pack ice near Jan Mayen ('West Ice') while the Northwest Atlantic population is thought to pup in the Davis Strait, in the Gulf of St. Lawrence (the 'Gulf'), and off southern Labrador or northeast Newfoundland (the 'Front'). We used microsatellite profiling of 300 individuals at 13 loci and mitochondrial DNA sequencing of the control region of 123 individuals to test for genetic differentiation between these four breeding herds. We found no significant genetic differences between breeding areas, nor evidence for cryptic nor higher level genetic structure in this species. The Greenland Sea breeding herd was genetically most distant from the Northwest Atlantic breeding areas; however, the differences were statistically nonsignificant. Our data therefore suggest that the world's hooded seals comprise a single panmictic genetic population.


Assuntos
Variação Genética , Focas Verdadeiras/genética , Animais , DNA Mitocondrial/química , Feminino , Fluxo Gênico , Marcadores Genéticos , Geografia , Haplótipos , Masculino , Repetições de Microssatélites , Filogenia , Dinâmica Populacional , Focas Verdadeiras/fisiologia , Análise de Sequência de DNA , Comportamento Sexual Animal
19.
Heart ; 91(8): 1003-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16020583

RESUMO

OBJECTIVE: To assess the relation of the metabolic insulin resistance syndrome (M-IRS) with coronary heart disease (CHD) in Pakistani patients. SUBJECTS: 200 patients with angiographic disease (CHD(+)) matched with 200 patients with chest pain without occlusive disease (CHD(-)). DESIGN: Prospective case-control study. SETTING: Tertiary referral cardiology unit in Pakistan. RESULTS: M-IRS was present in 37% of CHD(+) versus 27% of CHD(-) patients by criteria for white patients or 47% versus 42%, respectively, by Asian criteria (p < 0.001). After adjustment for other risk factors, M-IRS was not a significant predictor for CHD or angiographic disease. Age (p = 0.03), smoking (p < 0.001), diabetes-years (p = 0.003), sialic acid (p = 0.01), and creatinine (p = 0.008) accounted for the excess risk of CHD. Similarly, age (p = 0.005), creatinine (p < 0.001), cigarette pack-years (p = 0.02), diabetes-years (p = 0.003), and sialic acid (p = 0.08) were predictors of greater angiographic disease. M-IRS differed between Pakistani and white patients, as waist circumference correlated weakly (r = -0.03-0.08, p = 0.45-0.52) with triglycerides, high density lipoprotein cholesterol, systolic blood pressure, or glucose. Sialic acid was the only inflammatory marker associated with M-IRS. CONCLUSIONS: Despite strong associations between individual risk factors associated with M-IRS and a univariate association between M-IRS and CHD in native Pakistanis, the principal discriminant risk factors in this group are age, smoking, inflammation, diabetes-years, and impaired renal function. The poor sensitivity of M-IRS for CHD reflects the high underlying prevalence of M-IRS, thus reducing sensitivity, confounding by other urban lifestyle traits, or a lack of association of waist circumference with M-IRS risk factors. The definition of M-IRS may have to be revised to increase its power as a discriminant risk factor for CHD in Pakistani populations.


Assuntos
Doença da Artéria Coronariana/etiologia , Síndrome Metabólica/complicações , Doença da Artéria Coronariana/etnologia , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Síndrome Metabólica/etnologia , Pessoa de Meia-Idade , Paquistão/etnologia
20.
J Comp Physiol B ; 163(6): 433-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8071463

RESUMO

Measurements of growth, activity and energy consumption and estimates of milk intake were made in free-living, nursing ringed seal (Phoca hispida) pups. This was accomplished through the simultaneous use of time-depth recorders and the doubly labelled water technique. The pups spent an average of 52 +/- 7% of their time hauled out on the ice, 37 +/- 5% of the time in the water at the surface, and 11 +/- 5% of the time diving. Average daily mass gain of the pups (n=3) throughout the duration of the study period was 0.35 +/- 0.08 kg. The composition of the mass gain was 76% fat, 6% protein, and 18% water. The total water flux was measured to be 52 +/- 10 ml.kg-1.day-1. Average CO2 production was 0.85 +/- 0.16 ml.g-1.h-1, corresponding to a field metabolic rate of 0.55 +/- 0.10 MJ.kg-1.day-1, or 3.8 +/- 0.6 times the predicted basal metabolic rate based on body size (Kleiber 1975). Average daily milk intake was estimated to be 1379 +/- 390 ml. The field metabolic rate for the different components of seal pup activity budgets were calculated to be FMRhaul out = 1.34 BMR, FMRsurface = 6.44 BMR, and FMRdiving = 5.88 BMR.


Assuntos
Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Leite , Esforço Físico/fisiologia , Focas Verdadeiras/fisiologia , Animais , Animais Recém-Nascidos , Água Corporal/metabolismo , Dióxido de Carbono/metabolismo , Aumento de Peso
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