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21.
Studies increasingly show that social connectedness plays a key role in determining survival, in addition to natural and anthropogenic environmental factors. Few studies, however, integrated social, non-social and demographic data to elucidate what components of an animal''s socio-ecological environment are most important to their survival. Female giraffes (Giraffa camelopardalis) form structured societies with highly dynamic group membership but stable long-term associations. We examined the relative contributions of sociability (relationship strength, gregariousness and betweenness), together with those of the natural (food sources and vegetation types) and anthropogenic environment (distance from human settlements), to adult female giraffe survival. We tested predictions about the influence of sociability and natural and human factors at two social levels: the individual and the social community. Survival was primarily driven by individual- rather than community-level social factors. Gregariousness (the number of other females each individual was observed with on average) was most important in explaining variation in female adult survival, more than other social traits and any natural or anthropogenic environmental factors. For adult female giraffes, grouping with more other females, even as group membership frequently changes, is correlated with better survival, and this sociability appears to be more important than several attributes of their non-social environment.  相似文献   
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Aldabrachelys gigantea (Aldabra giant tortoise) is one of only two giant tortoise species left in the world and survives as a single wild population of over 100,000 individuals on Aldabra Atoll, Seychelles. Despite this large current population size, the species faces an uncertain future because of its extremely restricted distribution range and high vulnerability to the projected consequences of climate change. Captive‐bred A. gigantea are increasingly used in rewilding programs across the region, where they are introduced to replace extinct giant tortoises in an attempt to functionally resurrect degraded island ecosystems. However, there has been little consideration of the current levels of genetic variation and differentiation within and among the islands on Aldabra. As previous microsatellite studies were inconclusive, we combined low‐coverage and double‐digest restriction‐associated DNA (ddRAD) sequencing to analyze samples from 33 tortoises (11 from each main island). Using 5426 variant sites within the tortoise genome, we detected patterns of within‐island population structure, but no differentiation between the islands. These unexpected results highlight the importance of using genome‐wide genetic markers to capture higher‐resolution genetic structure to inform future management plans, even in a seemingly panmictic population. We show that low‐coverage ddRAD sequencing provides an affordable alternative approach to conservation genomic projects of non‐model species with large genomes.  相似文献   
24.
Classical homocystinuria is the most commonly inherited disorder of sulfur metabolism, caused by the genetic alterations in human cystathionine beta-synthase (CBS) gene. In this study, we present comprehensive clinical findings and the genetic basis of homocystinuria in a cohort of Turkish patients. Excluding some CBS mutations, detailed genotype–phenotype correlation for different CBS mutations has not been established in literature. We aimed to make clinical subgroups according to main clinical symptoms and discussed these data together with mutational analysis results from our patients. Totally, 16 different mutations were identified; twelve of which had already been reported, and four are novel (p.N93Y, p.L251P, p.D281V and c.829−2A>T). The probands were classified into three major groups according to the clinical symptoms caused by these mutations. A psychomotor delay was the most common diagnostic symptom (n = 12, 46.2% neurological presentation), followed by thromboembolic events (n = 6, 23.1% vascular presentation) and lens ectopia, myopia or marfanoid features (n = 5, 19.2% connective tissue presentation). Pyridoxine responsiveness was 7.7%; however, with partial responsive probands, the ratio was 53.9%.  相似文献   
25.
The purpose of this study is to investigate the relationship between the blood level of cadmium and the occurrence of ectopic pregnancy. Forty-one (41) case patients with ectopic pregnancy and 41 uncomplicated intrauterine pregnant patients as controls were recruited. The concentrations of cadmium (Cd) were measured from blood samples using atomic absorption spectrometry. The cases and controls were similar in age, body mass index, and smoking habits. The median blood level of Cd was 0.32 μg/l (interquartile range [IQR] 0.00–0.71) in the women with ectopic pregnancies and 0.34 μg/l (IQR 0.09–0.59) in the controls. There was no significant association between blood cadmium levels and ectopic pregnancy.  相似文献   
26.
Critical transitions are qualitative changes of state that occur when a stochastic dynamical system is forced through a critical point. Many critical transitions are preceded by characteristic fluctuations that may serve as model‐independent early warning signals, implying that these events may be predictable in applications ranging from physics to biology. In nonbiological systems, the strength of such early warning signals has been shown partly to be determined by the speed at which the transition occurs. It is currently unknown whether biological systems, which are inherently high dimensional and typically display low signal‐to‐noise ratios, also exhibit this property, which would have important implications for how ecosystems are managed, particularly where the forces exerted on a system are anthropogenic. We examine whether the rate of forcing can alter the strength of early warning signals in (1) a model exhibiting a fold bifurcation where a state shift is driven by the harvesting of individuals, and (2) a model exhibiting a transcritical bifurcation where a state shift is driven by increased grazing pressure. These models predict that the rate of forcing can alter the detectability of early warning signals regardless of the underlying bifurcation the system exhibits, but that this result may be more pronounced in fold bifurcations. These findings have important implications for the management of biological populations, particularly harvested systems such as fisheries, and suggest that knowing the class of bifurcations a system will manifest may help discriminate between true‐positive and false‐positive signals.  相似文献   
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BACKGROUND: Distinct virulence factors of Helicobacter pylori have been associated with clinical outcome of the infection; however, considerable variations have been reported from different geographic regions and data on genotypes of Turkish H. pylori isolates are sparse. AIM: To determine the prevalence of specific genotypes of H. pylori in Turkish patients with dyspepsia. MATERIALS AND METHODS: Ninety-three H. pylori-positive patients [30 with non-ulcer dyspepsia (NUD), 30 with duodenal ulcer (DU), and 33 with gastric cancer (GC)] who were admitted to our endoscopy unit due to dyspepsia were enrolled in the study. H. pylori infection was confirmed in all patients by histology and rapid urease test (RUT). The presence of vacA alleles, cagA, cagE, iceA, and babA2 genotypes were determined by polymerase chain reaction (PCR). Chi-squared test and Fisher's exact test were used for statistical comparisons and multivariate regression analysis was performed to find out independent predictors of different clinical outcomes. RESULTS: Turkish strains examined predominantly possessed the vacA s1,m2 (48.4%) and s1,m1 (40.7%) genotypes. The vacA s1a genotype was detected in 66.7, 96.4, and 87.9% of isolates from patients with NUD, DU, and GC, respectively, and its presence was significantly associated with that of DU (p = .004), GC (p = .043), and cagA gene (p = .021). None of the cases was found to harbor the s1c genotype. The frequencies of the cagA and cagE genes among studied isolates were 73.6 and 59.3%, respectively. The cagA gene was significantly associated with the presence of DU (p = .004) and GC (p = .003), and the cagE gene, too, was significantly associated with the presence of DU (p = .002) and GC (p = .000). All H. pylori isolates possessed the iceA gene. In all, 68 isolates (74.7%) were positive for iceA1 and 23 (25.3%) for iceA2. The frequency of icea1 gene was significantly higher in cases with GC (85%) than in cases with NUD (60%) (p = .026). The frequency of babA2 gene was 23.3, 46.4, and 87.9% in isolates of patients with NUD, DU, and GC, respectively. When compared to cases with NUD (p = .000) and DU (p = .000), the presence of babA2 gene was significantly higher in cases with GC. Multivariate regression analysis disclosed cagE (p = .006) and vacA s1a (p = .027) genotypes to be independent predictors of DU and babA2 (p = .000) and cagE (p = .013) genotypes to be independent predictors of GC. CONCLUSIONS: H. pylori vacA s1a, cagA, cagE genotypes have significant relations with the presence of DU and GC, and iceA1, babA2 with GC in Turkish patients with dyspepsia, whereas cagE and vacA s1a genotypes are independent predictors of DU, and babA2 and cagE genotypes are independent predictors of GC.  相似文献   
28.
Caffeic acid phenethyl ester (CAPE) is an active component of honeybee propolis extracts. Carbonic anhydrases (CAs, EC 4.2.1.1) are widespread and intensively studied metalloenzymes present in higher vertebrates including humans as many diverse isoforms. Acetylcholinesterase (AChE) is responsible for acetyl choline (ACh) hydrolysis and plays a fundamental role in nerve impulse transmission by terminating the action of the ACh neurotransmitter at cholinergic synapses and neuromuscular junctions. Butyrylcholinesterase (BChE) is another enzyme abundantly present in the liver and released into blood in a soluble form. Lactoperoxidase (LPO) is an enzyme involved in fighting pathogenic microorganisms whereas glutathione S-transferases (GSTs) are dimeric proteins present both in prokaryotic and eukaryotic organisms and involved in cellular detoxification mechanisms. In the present study, the inhibition effect of CAPE on human carbonic anhydrase (hCA) isoforms I, II, IX, and XII, AChE, BChE, LPO, and GST was evaluated. CAPE inhibited these enzymes with Kis in the range between micromolar to picomolar. The best inhibitory effect was observed against AChE and BChE.  相似文献   
29.
The Familial Mediterranean Fever (FMF) shows an autosomal recessive pattern of inheritance and affects certain ethnic groups. Disease is caused by mutations in MEFV gene and more than 180 mutations have been defined in affected individuals. Current study aimed to determine the frequency-type of the mutations for MEFV gene in Sivas??middle Anatolian city. The cohort was composed of 3340 patients. MEFV gene mutations were studied by multiplex PCR based reverse hybridization stripAssay method. Patients?? clinical features were; family history: 68%, erysipelas-like erythema: 17.6%, fever: 89.9%, abdominal pain: 84.2%, peritonitis: 90.2%, arthritis: 33%, pleuritis: 14.2%, parental consanguinity: 21.2%. Current results revealed that M694V is the most frequent mutation (43.12%), followed by E148Q (20.18), M680I(G/C) (15.00%) and V726A (11.32%). The study population has a high rate of carriers and the E148Q mutation frequency was found to be highest when compared to the other regions of Turkey and other Mediterranean groups.  相似文献   
30.
Functional & Integrative Genomics - This humble effort highlights the intricate details of metagenomics in a simple, poetic, and rhythmic way. The paper enforces the significance of the...  相似文献   
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