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21.
Analysis of the protein composition of urine has been the subject of much research that has captured the interest of scientific groups over the years. A number of factors have been isolated from urine that possess anti-neoplastic activities as seen both in vitro and in vivo studies. The urine from pregnant women and commercial preparations of crude clinical grade human chorionic gonadotropin contain factors (HAF for hCG associated factor) with anti-Kaposi's sarcoma activity. Also found in urine with activity are eosinophil-derived neurotoxin (EDN), anti-neoplastic urinary protein (ANUP), inhibin, activin A, and angiostatin. The anti-cancer activity of urinary proteins is associated with apoptosis of endothelial cells and of tumor-associated endothelial cells. A better understanding of the biological functions of these various urinary proteins, and of others that remain to be discovered, should provide insights into novel cell regulatory systems operating during pregnancy.  相似文献   
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The objective is to describe an outbreak of Trichophyton simii in a Cebus apella monkey colony in Argentine. During summer, alopecic zones appeared on dorsal regions from head to base of the tail of the animals. The hair and skin of nine animals were streaked onto Sabouraud dextrose with cloramphenicol and incubated at 25 degrees C. By the 10th day, white, filamentous colonies, which turned pale pink, developed from simples of four animals. Microscopical examinations were carried out and, because of colony and macroconidia morphology, were classified as Trichopyton simii. Although infection with T. simii is considered a zoonosis, we did not find human cases.  相似文献   
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The Galápagos giant tortoise is an icon of the unique, endemic biodiversity of Galápagos, but little is known of its parasitic fauna. We assessed the diversity of parasitic nematode communities and their spatial distributions within four wild tortoise populations comprising three species across three Galápagos islands, and consider their implication for Galápagos tortoise conservation programmes. Coprological examinations revealed nematode eggs to be common, with more than 80% of tortoises infected within each wild population. Faecal samples from tortoises within captive breeding centres on Santa Cruz, Isabela and San Cristobal islands also were examined. Five different nematode egg types were identified: oxyuroid, ascarid, trichurid and two types of strongyle. Sequencing of the 18S small-subunit ribosomal RNA gene from adult nematodes passed with faeces identified novel sequences indicative of rhabditid and ascaridid species. In the wild, the composition of nematode communities varied according to tortoise species, which co-varied with island, but nematode diversity and abundance were reduced or altered in captive-reared animals. Evolutionary and ecological factors are likely responsible for the variation in nematode distributions in the wild. This possible species/island-parasite co-evolution has not been considered previously for Galápagos tortoises. We recommend that conservation efforts, such as the current Galápagos tortoise captive breeding/rearing and release programme, be managed with respect to parasite biogeography and host-parasite co-evolutionary processes in addition to the biogeography of the host.  相似文献   
24.
Mitochondrial genome sequences have been widely used for evolutionary and phylogenetic studies. Among vertebrates, fish are an important, diverse group, and their mitogenome sequences are growing rapidly in public repositories. To facilitate mitochondrial genome analysis and to explore the valuable genetic information, we developed the Fish Mitogenome Resource (FMiR) database to provide a workbench for mitogenome annotation, species identification and microsatellite marker mining. The microsatellites are also known as simple sequence repeats (SSRs) and used as molecular markers in studies on population genetics, gene duplication and marker assisted selection. Here, easy-to-use tools have been implemented for mining SSRs and for designing primers to identify species/habitat specific markers. In addition, FMiR can analyze complete or partial mitochondrial genome sequence to identify species and to deduce relational distances among sequences across species. The database presently contains curated mitochondrial genomes from 1302 fish species belonging to 297 families and 47 orders reported from saltwater and freshwater ecosystems. In addition, the database covers information on fish species such as conservation status, ecosystem, family, distribution and occurrence downloaded from the FishBase and IUCN Red List databases. Those fish information have been used to browse mitogenome information for the species belonging to a particular category. The database is scalable in terms of content and inclusion of other analytical modules. The FMiR is running under Linux operating platform on high performance server accessible at URL http://mail.nbfgr.res.in/fmir.  相似文献   
25.
Wild type p53 exists in a constant state of equilibrium between wild type and mutant conformation and undergoes conformational changes at elevated temperature. We have demonstrated that the co-chaperone CHIP (carboxyl terminus of Hsp70-interacting protein), which suppressed aggregation of several misfolded substrates and induced the proteasomal degradation of both wild type and mutant p53, physically interacts with the amino terminus of WT53 and prevented it from irreversible thermal inactivation. CHIP preferentially binds to the p53 mutant phenotype and restored the DNA binding activity of heat-denatured p53 in an ATP-independent manner. In cells under elevated temperatures that contained a higher level of p53 mutant phenotype, CHIP restored the native-like conformation of p53 in the presence of geldanamycin, whereas CHIP-small interfering RNA considerably increased the mutant form. Further, under elevated temperatures, the levels of CHIP and p53 were higher in nucleus, and chromatin immunoprecipitation shows the presence of p53 and CHIP together upon the DNA binding site in the p21 and p53 promoters. We propose that CHIP might be a direct chaperone of wild type p53 that helps p53 in maintaining wild type conformation under physiological condition as well as help resurrect p53 mutant phenotype into a folded native state under stress condition.  相似文献   
26.
RAD51C is a member of the RecA/RAD51 protein family, which is known to play an important role in DNA repair by homologous recombination. In mice, it is essential for viability. Therefore, we have generated a hypomorphic allele of Rad51c in addition to a null allele. A subset of mice expressing the hypomorphic allele is infertile. This infertility is caused by sexually dimorphic defects in meiotic recombination, revealing its two distinct functions. Spermatocytes undergo a developmental arrest during the early stages of meiotic prophase I, providing evidence for the role of RAD51C in early stages of RAD51-mediated recombination. In contrast, oocytes can progress normally to metaphase I after superovulation but display precocious separation of sister chromatids, aneuploidy, and broken chromosomes at metaphase II. These defects suggest a possible late role of RAD51C in meiotic recombination. Based on the marked reduction in Holliday junction (HJ) resolution activity in Rad51c-null mouse embryonic fibroblasts, we propose that this late function may be associated with HJ resolution.  相似文献   
27.
Ribonuclease S peptide and S protein offer a unique complementation system to understand the finer features of molecular recognition. In the present study the S peptide (1-16), and its retro and retro-inverso analogs have been analyzed for their structural and biological attributes. RPHPLC, CD, and NMR analyses have revealed that the physicochemical and conformational properties of the S peptide are distinct from those of its retro and retro-inverso analogs. On the functional side, while the S peptide complemented the S protein to give RNase activity, was recognized by anti-S peptide antibodies and induced T cell proliferation, neither the retro nor the retro-inverso S peptides could do so.  相似文献   
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An economical and efficient one step synthesis of a series of 8-(arylidene)-4-(aryl)-5,6,7,8-tetrahydro-quinazolin-2-ylamines and 9-(arylidene)-4-(aryl)-6,7,8,9-tetrahydro-5H-cycloheptapyrimidin-2-ylamines by the reaction of bis-benzylidene cycloalkanones and guanidine hydrochloride in presence of NaH has been developed. All the synthesized compounds were evaluated against Mycobacterium tuberculosis H37Rv strain and the α-glucosidase and glycogen phosphorylase enzymes. Few of the compounds have shown interesting in vitro activity with MIC up to 3.12 μg/mL against M. tuberculosis and very good inhibition of α-glucosidase and glycogen phosphorylase enzymes. The most potent non toxic compound 40 exhibited about 58% ex vivo activity at MIC of 3.12 μg/mL. The present study opens a new gate to synthesize antitubercular agents for diabetic TB patients. In silico docking studies indicate that mycobacterial dihydrofolate reductase is the possible target of these compounds.  相似文献   
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