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51.

Genetic variations of microRNA encoding genes influence various sorts of diseases by modifying the expression or activity of microRNAs. MicroRNA 146a is an epigenetic regulator of immune response through controlling the type I interferon (IFN) and nuclear factor kappa B (NF-κB) pathways. Genetic variations of microRNA 146a impact the susceptibility to systemic lupus erythematosus (SLE) and its clinical presentations. This study aimed to investigate the polymorphisms of microRNA-146a gene (rs2431697 and rs57095329) in patients with SLE and its association with disease activity. Sixty-five patients with SLE and 40 apparently healthy controls were enrolled in this study. Patients were subjected to history taking, clinical examination, and disease activity evaluation by SLEDAI score. The microRNA-146a variants were determined by allele discrimination real-time PCR method in all participants. We found a statistically significant association between rs2431697 T allele and SLE (P-value?<?0.05), but there was no significant association between rs57095329 and SLE. The T/T genotype of microRNA-146a rs2431697 was associated with lupus nephritis, higher disease activity, and autoantibodies production. The microRNA-146a rs2431697 T allele could be a potential risk factor that contributes to SLE susceptibility, development of lupus nephritis, and disease activity.

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52.
Molecular Biology Reports - Lead (Pb) is one of the most common heavy metal pollutants affecting living organisms. It induces nephrotoxicity with significant alterations in renal structure and...  相似文献   
53.
This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage.  相似文献   
54.
Essential oils of fennel, peppermint, caraway, eucalyptus, geranium and lemon were tested for their antimicrobial activities against some plant pathogenic micro-organisms (Fusarium oxysporum, Alternaria alternate, Penicilium italicum Penicilium digitatum and Botyritus cinerea). Essential oils of fennel, peppermint, caraway were selected as an active ingredient for the formulation of biocides due to their efficiency in controlling the tested micro-organisms. Successful emulsifiable concentrates (biocides) were prepared from these oils using different emulsifiers (Emulgator B.L.M. Tween20 and Tween80) and different fixed oils (sesame, olive, cotton and soybean oils). Physico-chemical properties of the formulated biocide (spontaneous emulsification, emulsion stability test, cold stability and heat stability tests as well as viscosity, surface tension and pH) were measured. The prepared biocides were ready to be tested for application in a future work as a safe pesticide against different pathogens.  相似文献   
55.
This study was carried out to see the impact of Angoumois grain moth (AGM) on different cultivars of barley so that we must grow resistant variety of barley or improve those which are susceptible to it. Eggs of Sitotroga cerealella (Oliv.) were collected and reared in incubators available in Stored Product Entomology Laboratory, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, under temperature 27 ± 2°C and 60 ± 2% relative humidity. For the experiment, five different cultivars of barley; Sanober-96, Jau-83, Soorab-96, ICBA and Sterling were selected for AGM feed. After an interval of 30, 60 and 90 days of infestation, percentage damage and weight loss in grains were determined. After carrying out laboratory and field germination tests, viability of different cultivars were checked. Damage was maximum in variety Soorab (99.38%), which becomes susceptible while it was minimum in Sanober-96 (90.62%), which becomes resistant. Weight loss was maximum in variety Soorab (49.71%), which becomes susceptible and was minimum in Sanober-96 (45.32%), which becomes resistant. Damage was positively correlated with weight loss and negatively correlated with seed germination. In germination tests, on filter paper, maximum germination was found in variety Sterling (3%) which becomes resistant and it was minimum in ICBA which becomes susceptible (0%). In sand germination test, maximum seeds germinated in variety Sanober-96 (2%), and minimum seeds germinated in ICBA (0%). By calculating the percentage of losses of different cultivars, it was found that none of cultivars proved itself completely resistant or susceptible.  相似文献   
56.
The subcellular localization of the exoribonuclease RNase II is not known despite the advanced biochemical characterization of the enzyme. Here we report that RNase II is organized into cellular structures that appear to coil around the Escherichia coli cell periphery and that RNase II is associated with the cytoplasmic membrane by its amino-terminal amphipathic helix. The helix also acts as an autonomous transplantable membrane binding domain capable of directing normally cytoplasmic proteins to the membrane. Assembly of the organized cellular structures of RNase II required the RNase II amphipathic membrane binding domain. Co-immunoprecipitation of the protein from cell extracts indicated that RNase II interacts with itself. The RNase II self-interaction and the ability of the protein to assemble into organized cellular structures required the membrane binding domain. The ability of RNase II to maintain cell viability in the absence of the exoribonuclease polynucleotide phosphorylase was markedly diminished when the RNase II cellular structures were lost due to changes in the amphipathicity of the amino-terminal helix, suggesting that membrane association and assembly of RNase II into organized cellular structures play an important role in the normal function of the protein within the bacterial cell.  相似文献   
57.
The colonization patterns of oceanic islands are often interpreted through transmarine dispersal. However, in islands with intense human activities and unclear geological history, this inference may be inappropriate. Cyprus is such an island, whose geotectonic evolution has not been clarified yet to the desired level for biogeographical reconstructions, leaving the questions of ‘how the Cypriote biota arrived’ and ‘does the dispersal have the formative role in patterns of its diversification’ unanswered. Here, we address these issues through a reconstruction of the evolutionary history of six herptiles (Ablepharus budaki, Ophisops elegans, Acanthodactylus schreiberi, Telescopus fallax, Pelophylax cf. bedriagae, and Hyla savignyi) by means of mitochondrial DNA (cytochrome b and 16S rRNA), applying a Bayesian phylogenetic, biogeographical, and chronophylogenetic analyses. The phylogeographical analyses show that the colonization history of those species in Cyprus started in the late Miocene and extended into the Pliocene and Pleistocene, with geodispersal, transmarine dispersal, and human‐mediated dispersal having their share in shaping the diversification of Cypriote herptiles. The revealed patterns could be divided into three biogeographical categories: old colonizers that arrived in Cyprus during the late Miocene or early Pliocene either by a land bridge (geodispersal) which connected Cyprus with the mainland or by transmarine dispersal, younger colonizers that reached the island through transmarine dispersal from the Middle East, and new settlers that arrived through human‐induced (voluntary or not) introductions. This work advances our knowledge of the biogeography of Cyprus and highlights the need to consider both geo‐ and transmarine dispersal when dealing with islands whose associations do not have a straightforward interpretation. © 2013 The Linnean Society of London  相似文献   
58.
Identification and molecular characterization of Babesia gibsoni proteins with potential antigenic properties are crucial for the development and validation of the serodiagnostic method. In this study, we isolated a cDNA clone encoding a novel B. gibsoni 76-kDa protein by immunoscreening of the parasite cDNA library. Computer analysis revealed that the protein presents a glutamic acid-rich region in the C-terminal. Therefore, the protein was designated as B. gibsoni glutamic acid-rich protein (BgGARP). A BLASTp analysis of a translated BgGARP polypeptide demonstrated that the peptide shared a significant homology with a 200-kDa protein of Babesia bigemina and Babesia bovis. A truncated BgGARP cDNA (BgGARPt) encoding a predicted 13-kDa peptide was expressed in Escherichia coli (E. coli), and mouse antisera against the recombinant protein were used to characterize a corresponding native protein. The antiserum against recombinant BgGARPt (rBgGARPt) recognized a 140-kDa protein in the lysate of infected erythrocytes, which was detectable in the cytoplasm of the parasites by confocal microscopic observation. In addition, the specificity and sensitivity of enzyme-linked immunosorbent assay (ELISA) with rBgGARPt were evaluated using B. gibsoni-infected dog sera and specific pathogen-free (SPF) dog sera. Moreover, 107 serum samples from dogs clinically diagnosed with babesiosis were examined using ELISA with rBgGARPt. The results showed that 86 (80.4%) samples were positive by rBgGARPt-ELISA, which was comparable to IFAT and PCR as reference test. Taken together, these results demonstrate that BgGARP is a suitable serodiagnostic antigen for detecting antibodies against B. gibsoni in dogs.  相似文献   
59.
The aim of this study was to evaluate the efficacy of selected bacterial strains against the wheat soil‐borne pathogen Fusarium graminearum under greenhouse conditions. The most potent isolates were 3 isolates out of 18 isolates, which have numbers 3, 9 and 10 with in vitro inhibition index 42.5%, 41.3% and 46.3% respectively. Isolates 3 and 10 were selected for the following experiments. Isolates 3 and 10 were identified as Bacillus subtilis MAA03 and Pseudomonas fluorescens MAA10, respectively according to International Identification Keys and, confirmed by using Biolog system and 16S rDNA where the strains exhibited more than 99.5% sequence identity. Their close taxonomic relationship was further documented by phenotypic similarities. The using of B. subtilis and P. fluorescens separately or in mixture as biocontrol agent against F. graminearum on wheat significantly increased the final germination percent, the mean daily germination and germination index of wheat cultivar, while the mean germination time was significantly decreased relative to infested control. The final infection percent, the mean daily infection and infection index were decreased significantly, while the mean infection time was significantly increased relative to infested control. The use of P. fluorescens as biocontrol agent was the most efficient than B. subtilis or in mixture and the best treatment was seed coating. The application of B. subtilis and P. fluorescens separately or in combination significantly affected the growth parameters of wheat cultivar Tabuki, the root length was significantly increased in seed coating and seed soaking treatments, while non‐significantly decreased in case of soil drench treatment relative to infested control. Shoot length was significantly decreased in case of seed coating treatment relative to infested control. The shoot fresh and dry weights were significantly increased in seed coating and seed soaking treatments relative to infested control. The root fresh and dry weights were significantly increased in seed coating and seed soaking treatments relative to infested control. The number of leaves was significantly increased in all treatments relative to infested control.  相似文献   
60.
A series of novel 3-hydroxy vinylboronates which share structural similarities with sphingolipids were synthesized and tested in vitro and in vivo as anticancer agents. The molecules reduced cancer cell survival in vitro by influencing their sphingolipid metabolism. In a cancer model in nude mice the lead compound E7 prevented the development of tumor as long as the treatment period continued. Moreover, it delayed tumor growth after the treatment was finished.  相似文献   
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