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As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major wintering grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite = 208/46), Brazil (nnew mtDNA/microsatellite = 50/50), South Africa (nnew mtDNA/microsatellite = 66/77, npub mtDNA/microsatellite = 350/47), Chile-Peru (nnew mtDNA/microsatellite = 1/1), the Indo-Pacific (npub mtDNA/microsatellite = 769/126), and SG (npub mtDNA/microsatellite = 8/0, nnew mtDNA/microsatellite = 3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG, and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of 1 genetically identified individual between the South American grounds. The single sample from Chile-Peru had an mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic and were more similar to the South American than the South African wintering grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.
Assuntos
Variação Genética , Baleias/genética , Distribuição Animal , Migração Animal , Animais , Brasil , Chile , Comportamento Alimentar , Feminino , Técnicas de Genotipagem , Ilhas , Masculino , PeruRESUMO
Since 1970, blue whales (Balaenoptera musculus) have been seen feeding in the waters off southern Chile during the summer and autumn (December to May). Investigation of the genetic, acoustic and morphological characteristics of these blue whales shows that they are a distinct but unnamed subspecies, called the Chilean blue whales. Photo-identification surveys have been conducted in the waters off northwestern Isla Grande de Chiloé, southern Chile from 2004-2012 and Isla Chañaral, central Chile in 2012. Over this time, 1,070 blue whales were encountered yielding, after photo-quality control, 318 and 267 unique photographs of the left and right side of the flank respectively. Using mark-recapture analysis of left and right side photographs collected from Isla Grande de Chiloé (2004-2012), open population models estimate that ~570-760 whales are feeding seasonally in this region. POPAN superpopulation abundance estimates for the same feeding ground in 2012 are 762 (95% confidence intervals, CI = 638-933) and 570 (95% CI 475-705) for left and right side datasets respectively, very similar to results from closed population models. Estimates of trend revealed strong variation in abundance, peaking in 2009 and [suggesting] fluctuating use in the survey area over time, likely related to the density of their prey. High inter-annual return rates suggest a degree of site-fidelity of individuals to Isla Grande de Chiloé and that the number of whales using this feeding ground is relatively small.
Assuntos
Balaenoptera/fisiologia , Bases de Dados Factuais , Animais , Chile , Feminino , Masculino , Dinâmica Populacional , Estações do AnoRESUMO
BACKGROUND: Oxidative stress promotes endothelial dysfunction and atherosclerosis in chronic renal disease. OBJECTIVES: This study investigated the impact of Hatha yoga on oxidative stress indicators and oxidant status, in patients with end-stage renal disease (ESRD) on hemodialysis. DESIGN: This prospective randomized study consisted of 33 ESRD patients in the Hatha yoga exercise group who were matched with 35 ESRD patients in the control group. OUTCOME MEASURES: The oxidative stress indicators (malondialdehyde - MDA, protein oxidation - POX, phospholipase A2 - PLA2 activity) and the oxidative status (superoxide dismutase (SOD) and catalase activities) were determined in the blood samples taken at the pre-hemodialysis treatment, at baseline (0 months) and after four months. RESULTS: In patients in the Hatha yoga exercise group, lipid peroxidation, as indicated by MDA decreased by 4.0% after four months (P = 0.096). There was also a significant reduction in the activity of PLA from 2.68 ± 0.02 IU / L to 2.34 IU / L (- 12.7%; P = 0.010) and POX from 2.28 ± 0.02 nmol / mg to 2.22 ± 0.01 nmol / mg (- 22.6%; P = 0.0001). The activity of SOD significantly increased from 12.91 ± 0.17 U / L to 13.54 ± 0.15 U / L (4.65%; P = 0.0001) and catalase from 79.83 ± 0.63 U / L to 80.54 ± 0.80 U / L (0.90%; P = 0.0001). There was a significant correlation between the pre-hemodialysis oxidative stress parameters at the zero month and after four months for the activities of PLA (r = 0.440), catalase (r = 0.872), and SOD (r = 0.775). CONCLUSIONS: These findings suggest that the Hatha yoga exercise has therapeutic, preventative, and protective effects in ESRD subjects, by decreasing oxidative stress.
RESUMO
BACKGROUND: Dyslipidemia has been established as a well-known traditional risk factor for cardiovascular disease in chronic kidney disease patients. AIM: This study investigated the impact of Hatha yoga exercise on lipid parameters in patients with end-stage renal disease (ESRD) on hemodialysis. MATERIALS AND METHODS: This prospective randomized study consisted of 33 ESRD patients in the Hatha yoga exercise group that was matched with 35 ESRD patients in the control group. Serum total cholesterol, triglycerides, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol were determined at baseline (0 month) and after 4 months. RESULTS: Comparing values after 4 months versus baseline in the prehemodialysis Hatha yoga exercise group, there was found a significant decrease in total cholesterol from 5.126 ± 0.092 mmol/l to 4.891 ± 0.072 mmol/l (-4.58%; P = 0.0001), triglycerides from 2.699 ± 0.078 mmol/l to 2.530 ± 0.063 mmol/l (-6.26%; P = 0.0001), LDL-cholesterol from 2.729 ± 0.083 mmol/l to 2.420 ± 0.066 mmol/l (-11.32%; P = 0.0001), and total cholesterol/HDL-cholesterol ratio from 5.593 ± 0.119 mmol/l to 4.907 ± 0.116 mmol/l (-12.26%; P = 0.047). For patients in the Hatha yoga exercise group, 51.5% had normal total cholesterol at 0 month while 70.0% had normal total cholesterol (P < 0.05) after 4 four months and 54.5% of patients had normal LDL-cholesterol at 0 month while 84.9% had normal LDL-cholesterol after 4 months (P < 0.05). CONCLUSION: These findings suggest that Hatha yoga exercise has preventive and beneficial effects and may be a safe therapeutic modality in ESRD patients.
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Several studies have reported that mutations in genes involved in maintenance of genome integrity may be responsible for increased cancer risk. Human RAD51, known to function in DNA repair, interacts with a number of proteins implicated in breast cancer (BC), including BRCA1 and BRCA2. Few studies have investigated the role of RAD51 gene variations in familial BC. To detect potential novel gene defects that may contribute to hereditary BC susceptibility, 143 patients belonging to 143 Chilean families tested for BRCA1 and BRCA2 mutations were screened for mutations in RAD51, using conformational sensitive gel electrophoresis (CSGE) and DNA sequencing. No mutations were detected in the exon or splice-boundary regions of the RAD51 gene in these families. The RAD51 135G>C polymorphism (c.-98G>C, rs1801320) was studied in a case-control design, to evaluate its possible association with BC susceptibility. The frequency of the RAD51 135C allele was established in 143 cases and 247 controls, using restriction fragment length polymorphism-polymerase chain reaction. RAD51 135C genotypes (G/C and C/C) were associated with an increased BC risk only among women with (a) a family history of BC, (b) BRCA1/2 negative (n = 131), and (c) age at onset <50 years (P = 0.020; OR = 2.17, 95% CI = 1.11-4.24). Thus, we propose that RAD51 135G>C polymorphism presents an increased risk of familial BC in women with age < 50 years at diagnosis, and this polymorphism may be a BC risk variant. This finding should be confirmed in other populations.