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81.
Sub‐Saharan Africa is afflicted by high hypertension prevalence that is expected to rise even further along with increasing obesity rates. The present study aimed to investigate the role of visfatin in obesity and to explore associations of visfatin with markers of endothelial function and hemodynamics in African women compared to a well‐matched white sample. The present study involved urban African (n = 102) and white (n = 115) women from South Africa, individually matched for age and BMI. We measured blood pressure, cardiac output, and arterial compliance noninvasively, and analyzed visfatin as well as circulating markers of vascular function and inflammation in serum. Serum visfatin concentration did not differ between African and white women. Visfatin was unrelated to obesity in African women but positive associations for total and abdominal obesity were found in white women. Age‐ and obesity‐adjusted univariate and multivariate analyses revealed significant positive associations of visfatin with endothelin‐1 and fibrinogen in African women. Identical analyses in white women indicated a positive association of visfatin with C‐reactive protein and von Willebrand factor. Our findings suggest a possible role of visfatin in the cardiovascular system that seems to be independent of obesity in the African women.  相似文献   
82.
83.
The interactions of Paecilomyces lilacinus strain 251 with the arbuscular mycorrhizal fungus Glomus intraradices and their significance for the control of Meloidogyne incognita on tomato were investigated in greenhouse experiments. Application of P. lilacinus had no effect on the frequency and intensity of tomato root colonization by G. intraradices. Likewise, the decline of the nematophagous fungus densities after single application in soil was not affected by the presence of the mycorrhizal fungus. Single application of P. lilacinus, as pre-planting soil treatment, resulted in significant reduction of nematode damage. In contrast, mycorrhizal inoculation did not provide sufficient biocontrol. Combined application of the two agents did not enhance root protection compared to single treatments. Double treatment of mycorrhized seedlings with P. lilacinus, as seedling drench and pre-planting soil treatment, 4 and 1 week before transplanting, respectively, resulted in the highest reduction of the nematode damage. These results indicate the potential of the commercial P. lilacinus strain 251 and mycorrhiza for integration in nematode control strategies.  相似文献   
84.

Background

Osteogenesis imperfecta (OI) is a rare bone disorder. In 90% of cases, OI is caused by mutations in the COL1A1/2 genes, which code procollagen α1 and α2 chains. The main aim of the current research was to identify the mutational spectrum of COL1A1/2 genes in Estonian patients. The small population size of Estonia provides a unique chance to explore the collagen I mutational profile of 100% of OI families in the country.

Methods

We performed mutational analysis of peripheral blood gDNA of 30 unrelated Estonian OI patients using Sanger sequencing of COL1A1 and COL1A2 genes, including all intron-exon junctions and 5′UTR and 3′UTR regions, to identify causative OI mutations.

Results

We identified COL1A1/2 mutations in 86.67% of patients (26/30). 76.92% of discovered mutations were located in the COL1A1 (n = 20) and 23.08% in the COL1A2 (n = 6) gene. Half of the COL1A1/2 mutations appeared to be novel. The percentage of quantitative COL1A1/2 mutations was 69.23%. Glycine substitution with serine was the most prevalent among missense mutations. All qualitative mutations were situated in the chain domain of pro-α1/2 chains.

Conclusion

Our study shows that among the Estonian OI population, the range of collagen I mutations is quite high, which agrees with other described OI cohorts of Northern Europe. The Estonian OI cohort differs due to the high number of quantitative variants and simple missense variants, which are mostly Gly to Ser substitutions and do not extend the chain domain of COL1A1/2 products.
  相似文献   
85.
Cells experience multiple environmental stimuli simultaneously. To survive, they must respond accordingly. Unfortunately, the proper response to one stress easily could make the cell more susceptible to a second coexistent stress. To deal with such a problem, a cell must possess a mechanism that balances the need to respond simultaneously to both stresses. Our recent studies of ompR malT(Con) double mutants show that elevated expression of LamB, the outer membrane porin responsible for maltose uptake, causes cell death when the osmoregulator OmpR is disabled. To obtain insight into the nature of the death experienced by ompR malT(Con) mutants, we described the death process. On the basis of microscopic and biochemical approaches, we conclude that death results from a loss of membrane integrity. On the basis of an unbiased genome-wide search for suppressor mutations, we conclude that this loss of membrane integrity results from a LamB-induced envelope stress that the cells do not sufficiently perceive and thus do not adequately accommodate. Finally, we conclude that this envelope stress involves an imbalance in the lipopolysaccharide/porin composition of the outer membrane and an increased requirement for inorganic phosphate.  相似文献   
86.
A small percentage of human immunodeficiency virus (HIV)- and simian immunodeficiency virus (SIV)-infected individuals spontaneously control virus replication. The majority of these elite controllers mount high-frequency virus-specific CD4(+) T cell responses. To evaluate the role these responses might play in viral control, we depleted two elite controller macaques of CD4(+) cells. SIV-specific CD4(+) T cell responses did not return to baseline levels until 8 weeks postdepletion. Viral loads remained stable throughout the experiment, suggesting that SIV-specific CD4(+) T cell responses may not play a direct role in controlling chronic viral replication in these elite controllers.  相似文献   
87.
Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX).  相似文献   
88.
报道了内蒙古清水河黄土丘陵地区发现的紫萼藓科1新变种——缨齿藓菱形变种[Jaffueliobryum wrightii(Sull.)Thér.var.rhombicumX.L.BaiSarula],该变种与干旱山地岩面生境中的原变种缨齿藓[Jaffueliobryum wrightii(Sull.)Thér.]相似,生境的变化导致其形态发生变化,主要表现在上部细胞菱形和细胞壁背部强烈加厚,未分化的叶上部边缘细胞、中肋横切面细胞不分化,叶片长0.7~0.8mm,毛尖长0.8~1.3mm。文中对缨齿藓及其新变种的形态学特征,分布和生境进行了描述,并提供了显微照片,另外,列出了缨齿藓属5个种的检索表。  相似文献   
89.
目的研究长爪沙鼠发情周期,揭示发情规律,优化判定方法。方法连续18 d采集50只长爪沙鼠阴道上皮脱落细胞涂片,采用角化细胞计数法研究长爪沙鼠发情周期规律。比较瑞氏染色、HE染色和直接镜检判定发情周期4个时相的优缺点。结果长爪沙鼠的发情周期有稳定型、不稳定型、假孕三种类型。其中稳定型占68.6%,发情周期为(106.3±35.0)h,可分为4个时相。4个时相角化细胞的比例分别为发情前期(13.5±7.8)%、发情期(86.7±9.9)%、发情后期(27.9±12.8)%和发情间期(3.3±2.8)%。结论角化细胞计数能准确地判定长爪沙鼠的发情周期及各个时相。直接镜检法能快速反映阴道脱落细胞的形态。  相似文献   
90.
人TRAIL基因cDNA的克隆及其在COS—7细胞中的表达   总被引:1,自引:0,他引:1  
TRAIL(TNFrelatedapoptosisinducingligand)是最近克隆的肿瘤坏死因子(TNF)家族的新成员,由于它的蛋白质结构和生物学效应类似于FAS/APO1L,因此,也被称为APO2L。在低浓度下,TRAIL能迅速地诱导多种肿瘤细胞系的?..  相似文献   
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