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91.
The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human–carnivore conflict, which has led to long‐term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the ‘pre‐genomic era’ and the first insights of the ‘genomics era’. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large‐scale trends and patterns of genetic variation in European wolf populations, we conducted a meta‐analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south‐west (lowest genetic diversity) to north‐east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650?850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science‐based wolf conservation and management at regional and Europe‐wide scales.  相似文献   
92.
Large carnivore feeding ecology plays a crucial role for management and conservation for predators and their prey. One of the keys to this kind of research is to identify the species composition in the predator diet, for example, prey determination from scat content. DNA‐based methods applied to detect prey in predators’ scats are viable alternatives to traditional macroscopic approaches, showing an increased reliability and higher prey detection rate. Here, we developed a molecular method for prey species identification in wolf (Canis lupus) scats using multiple species‐specific marker loci on the cytochrome b gene for 18 target species. The final panel consisted of 80 assays, with a minimum of four markers per target species, and that amplified specifically when using a high‐throughput Nanofluidic array technology (Fluidigm Inc.). As a practical example, we applied the method to identify target prey species DNA in 80 wolf scats collected in Sweden. Depending on the number of amplifying markers required to obtain a positive species call in a scat, the success in determining at least one prey species from the scats ranged from 44% to 92%. Although we highlight the need to evaluate the optimal number of markers for sensitive target species detection, the developed method is a fast and cost‐efficient tool for prey identification in wolf scats and it also has the potential to be further developed and applied to other areas and large carnivores as well.  相似文献   
93.
BAFF (BLyS) and APRIL are TNF-like cytokines that support survival and differentiation of B cells. Recent studies have discovered a role for BAFF in augmenting both innate and adaptive immune responses as well as in collaborating with other inflammatory cytokines to promote the activation and differentiation of effector immune cells. BAFF is an important pathogenic factor in lupus mouse models and BAFF inhibition successfully delays disease onset in these mice, although the responsiveness to BAFF inhibition varies among different strains. These results have led to the development of inhibitors targeting BAFF and APRIL in humans. An anti-BAFF antibody has shown significant but modest efficacy in two Phase III clinical trials for moderately active SLE and other inhibitors are being developed or at early stages of clinical testing.  相似文献   
94.
Regulatory T cells (Tregs) are critical for maintenance of peripheral tolerance via suppression of T-cell responses, and absence of Tregs results in autoimmunity. The role of aberrations in the Treg pool for the development of systemic lupus erythematosus (SLE, lupus) remains uncertain. Treg-mediated generation of adenosine, dependent on the ectonucleotidase CD39, is an important mechanism for suppression of T-cell responses. We tested whether decreases in numbers of Tregs, and specifically CD39-expressing Tregs, are associated with human lupus. We studied 15 SLE patients, six patients with rheumatoid arthritis (RA) and 24 healthy controls. Treg phenotypic markers, including CD39 expression, were studied by flow cytometry. Varying numbers of sorted Tregs cells were co-cultured with responder T (Tresp) cells, with proliferation assessed by 3H-thymidine incorporation. The proportion of Tregs as defined by Foxp3+ CD25+high CD127−/low was similar in lupus and control populations. CD39-expressing Tregs comprised 37 ± 13% of the Treg population in healthy controls and 36 ± 21% in lupus subjects using nonsteroidal immunosuppressants to control active disease, but was nearly absent in five of six lupus subjects with minimally active disease. In contrast to healthy controls and lupus subjects without the CD39 defect, in SLE subjects with the CD39 defect, adenosine-dependent Treg-mediated suppression was nearly absent. These results suggest that functional defects in Tregs, rather than reduced Treg numbers, are important for the loss of peripheral tolerance in lupus. Presentation of this defect may serve as a biomarker for untreated disease.  相似文献   
95.
A 67-year-old gentleman presented to Yale-New Haven Hospital (YNHH) for assessment of a supratherapeutic INR and sacral lesion. Hematologic workup revealed elevated ESR, PT, INR, PTT, and CRP, mixing studies that failed to correct, and a positive Russell Viper Venom Test (RVVT), which confirmed the presence of lupus anticoagulant (LA), a subtype of antiphospholipid syndrome (APA). Pathology of the patient's sacral lesion revealed diffuse large B-cell lymphoma. This case provides insight into the association between APA and lymphoid neoplasm. The patient's unique presentation is in marked contrast to other reports of APA and lymphoid malignancy, which are typically associated with elevated PTT, normal PT, minimal extranodal disease, and potential thrombotic complications. Further, treatment with Rituximab-CHOP chemotherapy led to excellent clinical response with tumor remission and normalization of PT and PTT.  相似文献   
96.
We have previously reported the anti-inflammatory potential and the possible underlying mechanisms of Withangulatin A (WA), which is an active component isolated from Physalis angulata L. Here, we demonstrated that WA might improve the life quality, as well as reduced the accumulation of proteinuria symptoms and levels of anti-double-stranded DNA antibodies in MRL/lpr mice. Moreover, WA could improve renal histopathologic characteristics of MRL/lpr mice. Intriguingly, expression of B cell-activating factor (BAFF), BAFF-R and related gene in the spleen were significantly reduced in 10 mg/kg WA-treated mice compared with that in 5 mg/kg WA-treated mice and untreated mice. These findings indicate that WA might have a pleiotropic therapeutic effect through their immunosuppression via inhibiting BAFF signaling, which suggest a potential application of this active constituent in the treatment of SLE.  相似文献   
97.
用亲和层析法对6例正常人和4例SLE患者血清中抗DNA抗体进行提取和定量研究,发现正常人血清中抗DNA抗体的组成IgM/IgG大于1,是以IgM为主的抗体,SLE患者血清中抗DNA抗体含量高,IgM/IgG小于1,是以IgG为主的抗体。用胰蛋白酶降解提取的抗DNA抗体再借助于SDS—聚丙烯酰胺凝胶电泳对正常人和SLE患者抗DNA抗体的结构进行初步探讨,电泳结果表明正常人和SLE患者纯化抗DNA抗体经胰蛋白酶降解以后,正常人在52.2Kd区有一特异性降解片段,而SLE患者则在33.6Kd区有明显的降解片段富集,且表明它们是抗DNA—IgG所产生的。这说明SLE患者血清中抗DNA—IgG不仅在数量上比正常人有所增加,而且在结构上也有所不同。此外,这两种不同的抗DNA—IgG被胰蛋白酶降解的速度也有差异。  相似文献   
98.

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease, with multiple genetic and environmental factors involving in its etiology. The toll-like receptor 9 (TLR9) gene has been reported to have important roles in the development and progression of SLE. We performed a case–control study to investigate the effects of 4 SNPs in the TLR9 gene in the development of SLE in Northern Chinese population.

Methods

Four SNPs including rs187084, rs5743836, rs352139 and rs352140 were genotyped using the SNaPshot® method. A group of 430 SLE patients were compared to 424 normal controls. Data were analyzed by SPSS 17.0 and HaploView v 4.1 software.

Results

The frequency distributions of SNP rs351240 and haplotype H2 (TGCT) and H3 (CATT) were found to differ significantly between patient and control groups (p < 0.05), while other SNPs and haplotypes showed no significant difference between the two cohorts (p > 0.05).

Conclusion

The results revealed that variations in the TLR9 gene are associated with SLE, indicating that TLR9 may play an important role in the pathogenesis of SLE in the northern Chinese Han population.  相似文献   
99.
100.
目的:探讨系统性红斑狼疮并发低T3综合征的影响因素。方法:选择2102年6月~2013年6月于我科住院的SLE女性患者60例,其中伴有低T3综合征的30例(排除具有原发性甲状腺疾病的病例),甲状腺功能正常的30例,分析和比较伴有低T3综合征的SLE患者与甲状腺功能正常的SLE患者入院时的血常规、C反应蛋白、血沉、肝功能、肾功能、补体C3、补体C4、24小时尿蛋白等实验室指标和临床特征,并通过单因素和多因素Logistic回归分析探讨系统性红斑狼疮并发低T3综合征的影响因素。结果:伴有低T3综合征的SLE患者SLEDAI积分、红细胞计数、血红蛋白、血小板、补体C3、白蛋白、谷丙转氨酶、尿素、24小时尿蛋白定量与甲状腺功能正常的SLE患者比较均有统计学差异(P0.05);Logistic回归分析显示SLEDAI积分(OR=2.194,1.045~4.606,P=0.038)、血红蛋白(OR=0.719,0.518~0.998,P=0.049)、谷丙转氨酶(OR=2.417,1.071~5.457,P=0.034)、白蛋白(OR=0.313,0.105~0.934,P=0.037)是系统性红斑狼疮并发低T3综合征的影响因素。结论:SLEDAI积分和谷丙转氨酶水平是系统性红斑狼疮并发低T3综合征的危险性因素,而血红蛋白和白蛋白水平是其保护性因素。  相似文献   
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