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BReast CAncer gene 1 (BRCA1)—a tumor suppressor gene plays an important role in the DNA repair mechanism. Several BRCA1 variants perturb its structure and function, including synonymous and nonsynonymous single nucleotide polymorphisms (SNPs). In the present study, we performed in-silico analyses of nonsynonymous SNPs (nsSNPs) of the BRCA1 gene. In total, 122 nsSNPs were retrieved from the NCBI SNP database and in-silico analyses were performed using computational prediction tools: SIFT, PROVEAN, Mutation Taster, PolyPhen-2, MutPred, and ConSurf. Of these tools, SIFT, PROVEAN, and Mutation Taster predicted 61 out of 122 nsSNPs as “damaging”, based on structural homology analysis. PolyPhen-2 classified 22 nsSNPs as “probably damaging”. These nsSNPs were further analyzed by MutPred to predict basic molecular mechanisms of amino acid alteration. ConSurf analysis predicted eleven conserved amino acid residues with structural and functional consequences. We identified five amino acid residues in the RING finger domain (L22, C39, H41, C44, and C47) and two in the BRCT domain (P1771 and I1707) with the potential to deter the BRCA1 protein function. This study provides insights into the effect of nsSNPs and amino acid substitutions in BRCA1.

  相似文献   
23.
International Journal of Peptide Research and Therapeutics - Pseudomonas aeruginosa (P. aeruginosa) is a critical healthcare challenge due to its ability to cause persistent infections and the...  相似文献   
24.
This paper represents an attempt to investigate the mating behaviour of Symmorphus allobrogus, explaining the willingness of male to mount and copulate. The male displays including mode and frequency of antennation and position while copulating, the displays further comprises of intensity and frequency of rejecting behaviour. The presence of the male’s copulatory and postcopulatory courtship studies, understands the maintenance of monandry. The wasp has numerous secondary sexual characters, and the mating behaviour follows a phyletic and the specific sexual mating characters in context of sexual selection. The duration of mating phases and the number of male antennation series during precopulatory, copulatory and postcopulatory phases of mounting, differs significantly. Mating success depends mostly on the activities of male in the premounting phase and the behaviour of both sexes has a roughly equal importance for it in precopulatory phase. While during copulation, activity of male has little influence on its duration; however, behaviour of female has crucial effect, inducing its earlier termination.  相似文献   
25.
Vegetation analysis provides the prerequisites to understand the overall community structure and function of any ecosystem and is a fundamental requirement for the precise evaluation of biodiversity. Although many studies have assessed floristic attributes of specific areas, there are still unexplored regions, as is the case of the mountain region in the Kashmir Himalayas. Current research highlighted the recent findings of the scientific characterization of floristic and ecological aspects on the forest flora found in the Bhimber hills, Pakistan. Floristically, a total of 93 species belonging to 80 genera in 41 families were recorded. The species distribution patterns across the families were disproportionate with half of the species contributed by 8 families and 25 families were monotypic. Based on the floristic analysis, Asteraceae was the largest family with 12% of species followed by Poaceae with (11%) species. PAST software, a multivariate ecological community analysis was used to classify the species similarities and differences among the different habitat types. According to the habitat wise distribution, 21% of species were growing in the natural forest habitat, while 15% of species were dispersed in highly distributed habitats along roadsides and 8% on pedestrians. In terms of functional diversity, the herbaceous growth form was dominant (58%). The biological spectrum revealed therophytes as the dominant life form as it indicates the disturbed habitat vegetation. The phytogeographical analysis revealed that the maximum (69%) species were native, while the minimum (31%) species were exotic. Thus, the study of these functional and habitat diversity patterns can significantly improve our understanding of the ecological aspects of the flora in the geographical location. This information may additionally be useful in devising management plans to ensure sustainable utilization and better management of forest landscapes in this Himalayan region.  相似文献   
26.
Mutations in the voltage-gated potassium channel Kv7.4 (encoded as KCNQ4) lead to the early onset of non-syndromic hearing loss, which is significant during language acquisition. The deletion of the S269 pore residue (genetic Δ mutation) in Kv7.4 has been reported to be associated with hearing loss. So far, there is no mechanistic understanding of how this mutation modulates channel function. To understand the role of S269 in ion conduction, we performed molecular dynamics simulations for both wild type and ΔS269 mutant channels. Simulations indicate that the ΔS269 mutation suppresses the fluctuations in the neighboring Y269 residue and thereby consolidates the ring formed by I307 and F310 residues in the adjacent S6 helixes in the cavity region. We show that the long side chains of I307 near the entrance to the cavity form a hydrophobic gate. Comparison of the free energy profiles of a cavity ion in Kv7.4 and Kv7.4[ΔS269] channels reveals a sizable energy barrier in the latter case, which suppresses ion conduction. Thus the simulation studies reveal that the hydrophobic gate resulting from the ΔS269 mutation appears to be responsible for sensorineural hearing loss.  相似文献   
27.
A series of new benzenesulfonamides, most of which are chiral, incorporating 1, 3, 4-oxadiazole and amino acid moieties have been synthesized. Some of these compounds were screened for antimalarial activity and also evaluated for their ability to inhibit hem polymerization. The electrophoretic analysis indicated that one compound was effective in inhibiting the degradation of hemoglobin. The synthesized compounds were tested in mice infected with Plasmodium berghei. These derivatives have the potential for the development of novel antimalarial lead compounds.  相似文献   
28.
We have isolated Clostridium perfringens type B, an epsilon toxin-secreting bacillus, from a young woman at clinical presentation of Multiple Sclerosis (MS) with actively enhancing lesions on brain MRI. This finding represents the first time that C. perfringens type B has been detected in a human. Epsilon toxin’s tropism for the blood-brain barrier (BBB) and binding to oligodendrocytes/myelin makes it a provocative candidate for nascent lesion formation in MS. We examined a well-characterized population of MS patients and healthy controls for carriage of C. perfringens toxinotypes in the gastrointestinal tract. The human commensal Clostridium perfringens type A was present in approximately 50% of healthy human controls compared to only 23% in MS patients. We examined sera and CSF obtained from two tissue banks and found that immunoreactivity to ETX is 10 times more prevalent in people with MS than in healthy controls, indicating prior exposure to ETX in the MS population. C. perfringens epsilon toxin fits mechanistically with nascent MS lesion formation since these lesions are characterized by BBB permeability and oligodendrocyte cell death in the absence of an adaptive immune infiltrate.  相似文献   
29.

Background

There is little information about influenza among the Pakistani population. In order to assess the trends of Influenza-like-Illness (ILI) and to monitor the predominant circulating strains of influenza viruses, a country-wide lab-based surveillance system for ILI and Severe Acute Respiratory Illness (SARI) with weekly sampling and reporting was established in 2008. This system was necessary for early detection of emerging novel influenza subtypes and timely response for influenza prevention and control.

Methods

Five sentinel sites at tertiary care hospitals across Pakistan collected epidemiological data and respiratory samples from Influenza-like illness (ILI) and severe acute respiratory illness (SARI) cases from January 2008 to December 2011. Samples were typed and sub-typed by Real-Time RT-PCR assay.

Results

A total of 6258 specimens were analyzed; influenza virus was detected in 1489 (24%) samples, including 1066 (72%) Influenza type A and 423 (28%) influenza type B viruses. Amongst influenza A viruses, 25 (2%) were seasonal A/H1N1, 169 (16%) were A/H3N2 and 872 (82 %) were A(H1N1)pdm09. Influenza B virus circulation was detected throughout the year along with few cases of seasonal A/H1N1 virus during late winter and spring. Influenza A/H3N2 virus circulation was mainly observed during summer months (August-October).

Conclusions

The findings of this study emphasize the need for continuous and comprehensive influenza surveillance. Prospective data from multiple years is needed to predict seasonal trends for vaccine development and to further fortify pandemic preparedness.  相似文献   
30.
The effects of light, pH and organic carbon sources were investigated on hydrogen production by algae. An optical fiber was examined as an internal light source. The optical fiber rendered prolonged lag time and total time of hydrogen production. The optimal pH to produce hydrogen for Chlorella sp. was 8.0. Glucose, fructose, sucrose and malt extract were compared as organic carbon sources. The optimal dose of each carbon source was 5 g/L for maximum hydrogen yield. Sucrose produced the largest hydrogen volume (1,315 ml/L), while the highest production rate (24 ml/L/h) was observed in the presence of fructose.  相似文献   
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