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1.
A dominant mutation was generated in transgenic mice as a consequence of insertional mutation. Heterozygous mice from transgenic line 9257 (Tg(9257)) are hyperactive with bidirectional circling behavior and have a distinctive facial appearance due to hypoplasia of the nasal bone. Morphological analysis of the inner ear revealed asymmetric abnormalities of the horizontal canal and flattening or invagination of the crista ampullaris, which can account for the circling behavior. The sensory epithelium appeared to be normal. The transgene insertion site was localized by in situ hybridization to the B1 band of mouse chromosome 18. Genetic mapping in an interspecific backcross demonstrated the gene order centromere--Tg(9257)--8.8 +/- 3.4--Grl-1, Egr-1, Fgf-1, Apc--14.7 +/- 4.3--Pdgfr. The phenotype and the mapping data suggest that the transgene may be inserted at the Twirler locus. Homozygosity for the transgene results in prenatal lethality, but compound heterozygotes carrying the Tw allele and the transgene are viable. The function of the closely linked ataxia locus is not disrupted by the transgene insertion. This insertional mutant will provide molecular access to genes located in the Twirler region of mouse chromosome 18.  相似文献   
2.
DUF538 protein super family includes a number of plant proteins that their role is not yet clear. These proteins have been frequently reported to be expressed in plants under various stressful stimuli such as bacteria and elicitors. In order to further understand about this protein family we utilized bioinformatics tools to analyze its structure in details. As a result, plants DUF538 was predicted to be the partial structural homologue of BPI (bactericidal/permeability increasing) proteins in mammalian innate immune system that provides the first line of defense against different pathogens including bacteria, fungi, viruses and parasites. Moreover, on the base of the experimental data, it was identified that exogenously applied purified fused product of Celosia DUF538 affects the bacterial growth more possibly similar to BPI through the binding to the bacterial membranes. In conclusion, as the first ever time report, we nominated DUF538 protein family as the potential structural and functional homologue of BPI protein in plants, providing a basis to study the novel functions of this protein family in the biological systems in the future.  相似文献   
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The mesic Caspian (Hyrcanian) forest and ecotone communities provide a marked contrast to the arid and semiarid landscapes associated with most of the territory of Iran. To date, the ecological characteristics of these habitats, threatened and of conservation importance, have been little studied. Accordingly, ecological profiles of some important plant species of these communities have been assessed along two altitudinal gradients (300–2300 m a.s.l.). Vegetation and soils were sampled every 100 m in elevation, with the data subsequently analyzed using TWINSPAN and corrected frequency (CF) analyses. Relationships between soil variables (subdivided into three classes, the lowest, the middle and the upper third of all values) and herbaceous and shrub species (presence/absence data) were analyzed by the polythetic divisive classification method. 379 plant species and eleven soil variables – N, P, K, CaCO3, EC, pH, organic matter, C/N ratio and percentage of sand, clay and silt – were considered. The ecological profile method was used to evaluate the affinity and significance of associations between the probability of species’ occurrence and topsoil characteristics found by the polythetic method. Five vegetation groups were identified: two groups, with Acer campestre and Quercus macranthera in the tree layer and Veronica mazanderanae and Phuopsis stylosa as herbs, were restricted to forest-steppe ecotones and the upper mountain areas. Three groups, with Acer velutinum, Ruscus hyrcanus, Carpinus betulus, Danae racemosa, Fagus orientalis and Aruncus vulgaris as indicator species, occurred in the forest itself. Of the 42 plant species assessed as being of particular importance, 13 had significant relationships with eight soil factors. Thus, certain species, including endemic plant species of restricted distribution and conservation importance, can be used as indicators of particular soil conditions in the Hyrcanian forest area.  相似文献   
5.
There is information regarding the rates of gastric cancer (GC) in different populations and the important role of Helicobacter pylori in GC development; however, no comprehensive study has yet been performed to investigate the prevalence of GC in H. pylori–infected patients. PubMed, Embase, and Cochrane Library through January 1, 2000 were searched without language restrictions. Quality of included studies was assessed with a critical appraisal checklist recommended by the Joanna Briggs Institute. All of the analyses were conducted using Comprehensive Meta-Analysis Software Version 2.0 and Stata 14.0. Forty-four studies from 17 countries were included. The pooled frequency of GC was 17.4% (95% confidence interval: 16.4–18.5) in H. pylori–infected population. The frequency of GC among H. pylori–infected population varied markedly across countries. The highest rate of GC was observed in H. pylori–infected individuals from Asian countries. The frequency of GC was relatively high in H. pylori–infected population in the world. However, the eradication of H. pylori might be a promising strategy for GC prevention, especially in high-risk populations such as Asian countries.  相似文献   
6.
Together with mesangial cells, glomerular endothelial cells and the basement membrane, podocytes constitute the glomerular filtration barrier (GFB) of the kidney. Podocytes play a pivotal role in the progression of various kidney-related diseases such as glomerular sclerosis and glomerulonephritis that finally lead to chronic end-stage renal disease. During podocytopathies, the slit-diaphragm connecting the adjacent podocytes are detached leading to severe loss of proteins in the urine. The pathophysiology of podocytopathies makes podocytes a potential and challenging target for nanomedicine development, though there is a lack of known molecular targets for cell selective drug delivery. To identify VCAM-1 as a cell-surface receptor that is suitable for binding and internalization of nanomedicine carrier systems by podocytes, we investigated its expression in the immortalized podocyte cell lines AB8/13 and MPC-5, and in primary podocytes. Gene and protein expression analyses revealed that VCAM-1 expression is increased by podocytes upon TNFα-activation for up to 24 h. This was paralleled by anti-VCAM-1 antibody binding to the TNFα-activated cells, which can be employed as a ligand to facilitate the uptake of nanocarriers under inflammatory conditions. Hence, we next explored the possibilities of using VCAM-1 as a cell-surface receptor to deliver the potent immunosuppressant rapamycin to TNFα-activated podocytes using the lipid-based nanocarrier system Saint-O-Somes. Anti-VCAM-1-rapamycin-SAINT-O-Somes more effectively inhibited the cell migration of AB8/13 cells than free rapamycin and non-targeted rapamycin-SAINT-O-Somes indicating the potential of VCAM-1 targeted drug delivery to podocytes.  相似文献   
7.
The development of meiotic division and associated genetic recombination paved the way for evolutionary changes. However, the secondary and tertiary structure and functional domains of many of the proteins involved in genetic recombination have not been studied in detail. We used the human Dmc1 gene product along with secondary and tertiary domain structures of Escherichia coli RecA protein to help determine the molecular structure and function of maize Dmc1, which is required for synaptonemal complex formation and cell cycle progression. The maize recombinase Dmc1 gene was cloned and characterized, using rice Dmc1 cDNA as an orthologue. The deduced amino acid sequence was used for elaborating its 3-D structure, and functional analysis was made with the CDD software, showing significant identity of the Dmc1 gene product in Zea mays with that of Homo sapiens. Based on these results, the domains and motives of WalkerA and WalkerB as ATP binding sites, a multimer site (BRC) interface, the putative ssDNA binding L1 and L2 loops, the putative dsDNA binding helix-hairpin-helix, a polymerization motif, the subunit rotation motif, and a small N-terminal domain were proposed for maize recombinase Dmc1.  相似文献   
8.
In proteobacterial cytosol, ClpS protein is known as a molecular adaptor for substrate selectivity and proteolytic activity of the ATP-dependent chaperone-protease complex, ClpAP. ClpA-related ClpS is a small protein usually encoded immediately upstream of ClpA in the genome of proteobacteria. Recent bioinformatics analysis has revealed the presence of cyanobacterial-type ClpS or ClpC-related ClpS in organisms lacking ClpA, including all the plant species sequenced to date. Here we report the identification of an actinobacterial homologue of the ClpS (possibly Clp-related) gene from a plant system. A cDNA, spanning 566 bp with a complete coding region corresponding to 132 amino acids, was isolated from a Celosia cristata expression library constructed on a λ TriplEX2 vector. This cDNA product was considered to be an ATP-dependent Clp protease adaptor and was designated as Celosia actinobacterial-type ClpS, since it contains a highly conserved domain belonging to the ClpS family of proteins from actinobacteria. Celosia ClpS is about 80% identical to actinobacterial ClpS proteins in its overall deduced amino acid sequence. Based on this finding, we may define a novel target of ATP-dependent Clp complex in a plant system or speculate the presence of a second type of molecular chaperone besides ClpC in plants, as predicted for actinobacteria.  相似文献   
9.
A number of antiangiogenic drugs have been approved by the Food and Drug Administration which are used in cancer therapy, and variety of other agents in several stages of clinical development or in preclinical assessment. Among these, combretastatin A4 (CA-4) is an under-researched inhibitor of angiogenesis that shows potential activity in the treatment of advanced tumors with migration capacity. However, its clinical application has been limited due to poor water solubility, low bioavailability, rapid metabolism, and systemic elimination. During the last decade, numerous investigations have been done to overcome these problems by using different CA-4 delivery systems or developing produgs of CA-4 or its structural analogs. Nevertheless, these strategies could not be efficient out of the undesired side effects on normal tissues. Nanoliposomal CA-4 not only benefits from the advantage of using liposomal drugs as opposed to free drugs but also can accumulate in the tumor site via specific targeting ligands, which leads to efficient targeting and enhancement of bioavailability. To the best of our knowledge, we consider an important attempt to understand different factors that might influence the CA-4 loading and release pattern of liposomes and the consequent results in tumor therapy. In this review, we shed light on various studied liposomal CA-4 formulations showing application thereof in cancer treatment.  相似文献   
10.
Plants antiviral proteins are being used as anticancer agents and inhibit other viral diseases in humans. We modified the purification protocol of the two N-terminally blocked antiviral glycoproteins, CCP-25 and CCP-27, purified from the leaves of Celosia cristata. This not only gave rise to single pure samples with few steps of purification but also resulted in N-terminally free proteins. The extra purity of the samples was analyzed by reverse phase HPLC. Deglycosylation studies of CCP-25 with PNGase F enzyme revealed that its asparagine or asparagine-linked glycon contents are negligible. Partial N-terminal sequence of the CCP-25 showed the sequence (ANDIS), which seems to be conserved among plant antiviral proteins.  相似文献   
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