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61.
In this study, the aerial parts of Salvia hypargeia were subjected to hydrodistillation and the resulting compounds were analyzed in GC–MS. Antimicrobial activity of S. hypargeia essential oil (EO) against A. baumannii, S. aureus, and C. tropicalis were determined by agar well diffusion assay and microdilution method. Antimicrobial mechanism of the EO were investigated based on change of TTC-dehydrogenase relative, leakages of intracellular protein, DNA and potassium ion (K +). The main components of the EO were β-pinene, 1,8-cineole, camphor, α-pinene, 4-terpineol, and 4-thujanol. The MICs of the EO against the microorganisms were 15.2 mg/mL for S. aureus, 17.5 mg/mL for C. tropicalis and 28.8 mg/mL for A. baumannii. The inhibition zones were 18.16 mm, 25.01 mm, and 27.01 mm for A. baumannii, S. aureus, and C. tropicalis, respectively (p < 0.05). An increase in DNA, protein and K+ leakage was observed when microorganisms were exposed to the EO. The TTC-DRA of the treated microorganism cells was also significantly decreased because of slowing the respiration. The present study provided an experimental basis of practical application of S. hypargeia EO as a natural agent.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12088-021-00939-1.  相似文献   
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Genetic factors that contribute to the risk of breast cancer are largely not known and association studies have revealed several genes with low penetrance risk alleles for breast cancer. Analysis of these genes may provide important information on the risk factors affecting carcinogenesis. Variations in the ARLTS1, RAD51 and MDM2 genes have been associated with increased risk of different cancer types but for breast cancer the results are not consistent. In this study we investigated the role of the allelic variants in candidate genes acting in the tumor suppressor, DNA repair and p53 pathways as risk factors for familial breast cancer in 147 patients displaying characteristics of familial disease. Presence of the polymorphic variants were investigated by amplification of the corresponding regions and restriction fragment length polymorphism analysis. Genotype and allele frequencies in the patients were significantly different for all three variants. Our results indicate that the polymorphic variants might affect individual susceptibility towards breast cancer.  相似文献   
65.
Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disorder with the responsible gene of MEFV which primarily affects Jewish, Armenian, Turkish and Arab populations. The FMF gene (MEFV) has recently been cloned to chromosome 16p, which encodes pyrin. In the present study, we enrolled 2,067 unrelated patients with the suspicion of FMF in Middle Anatolia between the years 2006–2009 and identified the 12 MEFV mutations. DNA was amplified by PCR and subjected to reverse hybridization for the detection of MEFV gene mutations. Among the 2,067 patients, 866 (41.9%) were males and 1,201 (58.1%) were females. The mutations were homozygous in 176 (16.85%) patients, compound heterozygous in 314 (30.1%) patients, heterozygous in 546 (52.25%) patients and the other forms of mutations were found in 8 patients (0.76%). No mutation was detected in 1,023 (49.5%) patients. The most frequent mutations were M694V, M680I (G/C), E148Q and V726A. We could not find any significant differences between the two common mutations according to the gender. The high incidence of MEFV gene mutations in the Turkish population indicated that newborn screening may be discussed in the future. Because of the ethnic origin of Anatolia, larger serial analyses are necessary to investigate the rate and coexistence of these mutations.  相似文献   
66.
Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima-media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64?±?0.11 vs 0.42?±?0.05, p?相似文献   
67.
The C-terminus of Protein Tyrosine Phosphatase 1B (PTP1B) includes an α-helix α7), which forms an allosteric binding site 20 ? away from the active site. This helix is specific to PTP1B and its truncation decreases the catalytic activity significantly. Here, molecular dynamics (MD) simulations in the presence and absence of α7 were performed to investigate the role played by α7. The highly mobile α7 was found to maintain its contacts with loop 11 (L11)α3 helix throughout the simulations. The interactions of Tyr152 on L11, Tyr176, Thr177 on the catalytically important WPD loop and Ser190 on α3 are important for the conformational stability and the concerted motions of the regions surrounding the WPD loop. In the absence of α7, L11 and WPD loop move away from their crystal structure conformations, resulting in the loss of the interactions in this region, and a decrease in the residue displacement correlations in the vicinity of WPD loop. Therefore, we suggest that one of the functionally important roles of α7 may be to limit the L11 and α3 motions, and, facilitate the WPD loop motions. Truncation of α7 in PTP1B is found to affect distant regions as well, such as the substrate recognition site and the phosphate binding-loop (P-loop), changing the conformations of these regions significantly. Our results show that the PTP1B specific α7 is important for the conformation and dynamics of the WPD loop, and also may play a role in ligand binding.  相似文献   
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Background

Turkey is a crossroads of major population movements throughout history and has been a hotspot of cultural interactions. Several studies have investigated the complex population history of Turkey through a limited set of genetic markers. However, to date, there have been no studies to assess the genetic variation at the whole genome level using whole genome sequencing. Here, we present whole genome sequences of 16 Turkish individuals resequenced at high coverage (32 × -48×).

Results

We show that the genetic variation of the contemporary Turkish population clusters with South European populations, as expected, but also shows signatures of relatively recent contribution from ancestral East Asian populations. In addition, we document a significant enrichment of non-synonymous private alleles, consistent with recent observations in European populations. A number of variants associated with skin color and total cholesterol levels show frequency differentiation between the Turkish populations and European populations. Furthermore, we have analyzed the 17q21.31 inversion polymorphism region (MAPT locus) and found increased allele frequency of 31.25% for H1/H2 inversion polymorphism when compared to European populations that show about 25% of allele frequency.

Conclusion

This study provides the first map of common genetic variation from 16 western Asian individuals and thus helps fill an important geographical gap in analyzing natural human variation and human migration. Our data will help develop population-specific experimental designs for studies investigating disease associations and demographic history in Turkey.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-963) contains supplementary material, which is available to authorized users.  相似文献   
69.
Sequence similarity tools, such as BLAST, seek sequences most similar to a query from a database of sequences. They return results significantly similar to the query sequence and that are typically highly similar to each other. Most sequence analysis tasks in bioinformatics require an exploratory approach, where the initial results guide the user to new searches. However, diversity has not yet been considered an integral component of sequence search tools for this discipline. Some redundancy can be avoided by introducing non-redundancy during database construction, but it is not feasible to dynamically set a level of non-redundancy tailored to a query sequence. We introduce the problem of diverse search and browsing in sequence databases that produce non-redundant results optimized for any given query. We define diversity measures for sequences and propose methods to obtain diverse results extracted from current sequence similarity search tools. We also propose a new measure to evaluate the diversity of a set of sequences that is returned as a result of a sequence similarity query. We evaluate the effectiveness of the proposed methods in post-processing BLAST and PSI-BLAST results. We also assess the functional diversity of the returned results based on available Gene Ontology annotations. Additionally, we include a comparison with a current redundancy elimination tool, CD-HIT. Our experiments show that the proposed methods are able to achieve more diverse yet significant result sets compared to static non-redundancy approaches. In both sequence-based and functional diversity evaluation, the proposed diversification methods significantly outperform original BLAST results and other baselines. A web based tool implementing the proposed methods, Div-BLAST, can be accessed at cedar.cs.bilkent.edu.tr/Div-BLAST  相似文献   
70.
Ecosystems are interconnected by energy fluxes that provide resources for the inhabiting organisms along the transition zone. Especially where in situ resources are scarce, ecosystems can become highly dependent on external resources. The dependency on external input becomes less pronounced in systems with elevated in situ production, where only consumer species close to the site of external input remain subsidized, whereas species distant to the input site rely on the in situ production of the ecosystem. It is largely unclear though if this pattern is consistent over different consumer species and trophic levels in one ecosystem, and whether consumer species that occur both proximate to and at a distance from the input site differ in their dependency on external resource inputs between sites. Using stable isotope analysis, we investigated the dependency on external marine input for common ground‐associated consumer taxa on small tropical islands with high in situ production. We show that marine input is only relevant for strict beach‐dwelling taxa, while the terrestrial vegetation is the main carbon source for inland‐dwelling taxa. Consumer species that occurred both close (beach) and distant (inland) to the site of marine input showed similar proportions of marine input in their diets. This supports earlier findings that the relevance of external resources becomes limited to species close to the input site in systems with sufficient in situ production. However, it also indicates that the relevance of external input is also species‐dependent, as consumers occurring close and distant to the input site depended equally strong or weak on marine input.  相似文献   
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