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11.
Genetic connectivity of a coral reef ecosystem predator: the population genetic structure and evolutionary history of the Caribbean reef shark (Carcharhinus perezi) 下载免费PDF全文
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Frances MK Williams 《Arthritis research & therapy》2009,11(5):130-2
The field of biomarkers is a growing one, particularly in osteoarthritis (OA). OA is the most common disabling condition in
older persons and a major cause of morbidity. While the debate continues about which of the involved tissues - cartilage,
bone or synovium - is the most important in OA aetiology, there is no doubt that the three develop abnormalities in concert;
perhaps a truly useful biomarker will reflect just that. While efforts continue to identify reliable biomarkers useful for
characterising the status, prognosis and measurement of treatment response in OA, combining existing biomarkers to improve
their accuracy looks promising. 相似文献
15.
Rodrigo R. Domingues Alexandre W. S. Hilsdorf Mahmood M. Shivji Fabio V. H. Hazin Otto B. F. Gadig 《Reviews in Fish Biology and Fisheries》2018,28(1):213-227
The silky shark, Carcharhinus falciformis, is a large-bodied, oceanic-coastal, epipelagic species found worldwide in tropical and subtropical waters. Despite its commercial importance, concerns about overexploitation, and likely ecological significance of this shark as an upper trophic-level predator, understanding of its population dynamics remains unclear for large parts of its distribution. We investigated the genetic diversity, population structure and demographic history of the silky shark along the western Atlantic Ocean based on the use of 707 bp of the mitochondrial DNA control region (mtCR). A total of 211 silky sharks were sampled, originating from five areas along the western Atlantic Ocean. The mitochondrial sequences revealed 40 haplotypes, with overall haplotype and nucleotide diversities of 0.88 (± 0.012) and 0.005 (± 0.003), respectively. The overall population structure was significantly different among the five western Atlantic Ocean regions. Phylogenetic analysis of mtCR sequences from globally sourced silky shark samples revealed two lineages, comprising a western Atlantic lineage and western Atlantic—Indo-Pacific lineage that diverged during the Pleistocene Epoch. In general, tests for the demographic history of silky sharks supported a population expansion for both the global sample set and the two lineages. Although our results showed that silky sharks have high genetic diversity, the current high level of overexploitation of this species requires long-term, scientifically informed management efforts. We recommend that fishery management and conservation plans be done separately for the two western Atlantic matrilineal populations revealed here. 相似文献
16.
Mark J. Corcoran Bradley M. Wetherbee Mahmood S. Shivji Matthew D. Potenski Demian D. Chapman Guy M. Harvey 《PloS one》2013,8(3)
Southern stingrays, Dasyatis americana, have been provided supplemental food in ecotourism operations at Stingray City Sandbar (SCS), Grand Cayman since 1986, with this site becoming one of the world’s most famous and heavily visited marine wildlife interaction venues. Given expansion of marine wildlife interactive tourism worldwide, there are questions about the effects of such activities on the focal species and their ecosystems. We used a combination of acoustic telemetry and tag-recapture efforts to test the hypothesis that human-sourced supplemental feeding has altered stingray activity patterns and habitat use at SCS relative to wild animals at control sites. Secondarily, we also qualitatively estimated the population size of stingrays supporting this major ecotourism venue. Tag-recapture data indicated that a population of at least 164 stingrays, over 80% female, utilized the small area at SCS for prolonged periods of time. Examination of comparative movements of mature female stingrays at SCS and control sites revealed strong differences between the two groups: The fed animals demonstrated a notable inversion of diel activity, being constantly active during the day with little movement at night compared to the nocturnally active wild stingrays; The fed stingrays utilized significantly (p<0.05) smaller 24 hour activity spaces compared to wild conspecifics, staying in close proximity to the ecotourism site; Fed stingrays showed a high degree of overlap in their core activity spaces compared to wild stingrays which were largely solitary in the spaces utilized (72% vs. 3% overlap respectively). Supplemental feeding has strikingly altered movement behavior and spatial distribution of the stingrays, and generated an atypically high density of animals at SCS which could have downstream fitness costs for individuals and potentially broader ecosystem effects. These findings should help environmental managers plan mitigating measures for existing operations, and develop precautionary policies regarding proposed feeding sites. 相似文献
17.
A Sghaier-Ayadi M Feki I Bezrati-Ben Ayed O Abene MK Ben Fredj K Kaabachi A Chaouachi 《Biology of sport / Institute of Sport》2015,32(4):281-287
Recent reports suggest that hypovitaminosis D in athletes is as common as in the general population. This study was devised to examine vitamin D status and determinants of deficiency in athletes living in a sunny country (Tunisia). One hundred and fifty national elite athletes, training outdoors (n = 83) or indoors (n = 67), were enrolled from January to February 2012. Plasma 25-hydroxyvitamin D was measured by radioimmunoassay. Concentrations were between 50 and 75 nmol · l-1 in 21.3% of participants, between 25 and 50 nmol · l-1 in 55.3% of participants and <25 nmol · l-1 in 14.7% of participants. The concentrations were significantly lower in indoor athletes than outdoor athletes (36.2±19.0 nmol · l-1 vs. 49.1±19.2 nmol · l-1; p < 0.001). In multivariate analysis, vitamin D deficiency (25-hydroxyvitamin D <50 nmol · l-1) was associated with indoor sports [multi-adjusted odds ratio (95% confidence interval), 5.03 (1.64-15.4); p = 0.005], female gender [3.72 (1.44-9.65); p = 0.007] and age < 18 years [2.40 (1.01-5.85); p = 0.05]. Athletes living in sun-rich environments are exposed to a high risk of vitamin D inadequacy. Given the importance of vitamin D in health and athletic ability, targeting sufficient levels of plasma 25-hydroxyvitamin D in athletes is well justified. 相似文献
18.
An internal standard for porphyrin analysis 总被引:2,自引:0,他引:2
Robert E. Carlson Ramani Sivasothy David Dolphin Melvyn Bernstein Ally Shivji 《Analytical biochemistry》1984,140(2):360-365
The routine clinical analysis of the porphyrin precursors of heme requires an internal standard to determine the efficiency of the analytical procedure used. 2-Vinyl-4-hydroxymethyldeuteroporphyrin IX has been prepared as an internal standard. Its application to porphyrin analysis has been demonstrated using high-performance liquid chromatographic resolution of the uro- to protoporphyrins in normal and porphyric urine. 相似文献
19.
Guma MK Abdeldaim Kristoffer Strålin Jens Korsgaard Jonas Blomberg Christina Welinder-Olsson Björn Herrmann 《BMC microbiology》2010,10(1):310
Background
Streptococcus pneumoniae and Haemophilus influenzae cause pneumonia and as Neisseria meningitidis they are important agents of meningitis. Although several PCR methods have been described for these bacteria the specificity is an underestimated problem. Here we present a quantitative multiplex real-time PCR (qmPCR) for detection of S. pneumoniae (9802 gene fragment), H. influenzae (omp P6 gene) and N. meningitidis (ctrA gene). The method was evaluated on bronchoalveolar lavage (BAL) samples from 156 adults with lower respiratory tract infection (LRTI) and 31 controls, and on 87 cerebrospinal fluid (CSF) samples from meningitis patients. 相似文献20.
The basking shark (Cetorhinus maximus) is found in temperate waters throughout the world's oceans, and has been subjected to extensive exploitation in some regions. However, little is known about its current abundance and genetic status. Here, we investigate the diversity of the mitochondrial DNA control region among samples from the western North Atlantic, eastern North Atlantic, Mediterranean Sea, Indian Ocean and western Pacific. We find just six haplotypes defined by five variable sites, a comparatively low genetic diversity of pi=0.0013 and no significant differentiation between ocean basins. We provide evidence for a bottleneck event within the Holocene, estimate an effective population size (Ne) that is low for a globally distributed species, and discuss the implications. 相似文献