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51.
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   
52.
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   
53.
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   
54.
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   
55.
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   
56.
The Persian Lizard, Iranolacerta brandtii, was until recently considered to be restricted to north-western Iran (Azerbaijan and Esfahan provinces). However, two recent studies have revealed the existence of populations in Eastern Anatolia, extending the range of this species for about 230?km westwards. The fragmented distribution of this species has been considered to be a consequence of the climatic oscillations during the Pleistocene and Holocene, which created events of alternating contact and isolation of populations in distinct glacial refugia. According to our obtained genealogy derived from three mitochondrial fragments (12S rRNA, 16S rRNA and cytb), the Turkish specimens cluster together but form an independent clade, sister to the individuals from Tabriz in Iran. The separation of these two clades is concurrent with the cladogenesis between the Esfahan and Ardabil clades, estimated to have taken place during the late Holocene.  相似文献   
57.
58.

Objectives

To assess the effects of non-communicable diseases, such as diabetes, hypertension and obesity, on the mother and the infant.

Methods

A multicentre cohort study was conducted in three hospitals in the city of Riyadh in Saudi Arabia. All Saudi women and their babies who delivered in participating hospitals were eligible for recruitment. Data on socio-demographic characteristics in addition to the maternal and neonatal outcomes of pregnancy were collected. The cohort demographic profile was recorded and the prevalence of maternal conditions including gestational diabetes, pre-gestational diabetes, hypertensive disorders in pregnancy and obesity were estimated.

Findings

The total number of women who delivered in participating hospitals during the study period was 16,012 of which 14,568 women participated in the study. The mean age of the participants was 29 ± 5.9 years and over 40% were university graduates. Most of the participants were housewives, 70% were high or middle income and 22% were exposed to secondhand smoke. Of the total cohort, 24% were married to a first cousin. More than 68% of the participants were either overweight or obese. The preterm delivery rate was 9%, while 1.5% of the deliveries were postdate. The stillbirth rate was 13/1000 live birth. The prevalence of gestational diabetes was 24% and that of pre-gestational diabetes was 4.3%. The preeclampsia prevalence was 1.1%. The labour induction rate was 15.5% and the cesarean section rate was 25%.

Conclusion

Pregnant women in Saudi Arabia have a unique demographic profile. The prevalence of obesity and diabetes in pregnancy are among the highest in the world.  相似文献   
59.
Exosomal GAPDH from Proximal Tubule Cells Regulate ENaC Activity   总被引:1,自引:0,他引:1  
Exosomes are nanometer-scale, cell-derived vesicles that contain various molecules including nucleic acids, proteins, and lipids. These vesicles can release their cargo into adjacent or distant cells and mediate intercellular communication and cellular function. Here we examined the regulation of epithelial sodium channels in mpkCCD cells and distal tubule Xenopus 2F3 cells by exosomes isolated from proximal tubule LLC-PK1 cells. Cultured mpkCCD cells were stained with CTX coupled to a green fluorophore in order to label the cell membranes and freshly isolated exosomes from LLC-PK1 cells were labeled with the red lipophilic dye PKH26 in order to visualize uptake of exosomes into the cells. Single-channel patch clamp recordings showed the open probability of ENaC in Xenopus 2F3 cells and in freshly isolated split-open tubules decreased in response to exogenous application of exosomes derived from LLC-PK1 proximal tubule cells. Active GAPDH was identified within exosomes derived from proximal tubule LLC-PK1 cells. The effect on ENaC activity in Xenopus 2F3 cells was blunted after application of exosomes transfected with the GAPDH inhibitor heptelidic acid. Also, we show GAPDH and ENaC subunits associate in mpkCCD cells. These studies examine a potential role for exosomes in the regulation of ENaC activity and examine a possible mechanism for communication from proximal tubule cells to distal tubule and collecting duct cells.  相似文献   
60.
Recent studies suggest that magnetic susceptibility (MS) measurements can play an important role in identifying zones where microbial-mediated iron mineral transformations are occurring. Here we investigated the microbial community variations within zones of elevated MS in a petroleum hydrocarbon-contaminated aquifer near Bemidji, Minnesota, USA. Our main objective was to 1) identify the key microbial populations that may play a role in hydrocarbon degradation, 2) analyze which microbial populations could be connected to the elevated MS and 3) explore the use of non-destructive geophysical techniques as a tool to guide microbial sampling. Clone libraries based on the 16S rRNA gene revealed the presence of iron-reducing β-Proteobacteria in the vadose zone, whereas the free petroleum phase on the water table was characterized by a methanogenic consortium, in which the syntrophic δ-proteobacterium Smithella and the hydrogenotrophic Methanoregula predominated. Nonmetric multidimensional scaling (NMDS) found a close relationship between elevated MS values and the methanogenic hydrocarbon-degrading consortium. Our results suggest that magnetic susceptibility measurements can guide microbiologists to zones of active microbial biodegradation in aged petroleum spills.  相似文献   
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