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41.
Spores of Ganoderma applanatum were collected by gravity. The spore extract was prepared and its biochemical and immunological properties were examined. In isoelectric focusing, the extract had 10–12 bands with pl values between 3.5 to 6.0, the strongest being at 3.5, 3.75, 4.55 and 5.2. In crossedradioimmunoelectrophoresis using human atopic sera, the extract had two dominant and two minor allergens. In IgE immunoblots of sodium dodecylsulphate polyacrylamide gel electrophoresis, the extract showed reactivity at 82, 45, 33, 26, 16, 11 kDa MW, the strongest being at 45 kDa MW. These results indicate that G. applanatum contains a complex mixture of allergens.  相似文献   
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C5-Ethynylbenzenesulfonamide-modified nucleotide (EBNA) was investigated as substrate of various DNA polymerases. The experiments revealed that KOD, Phusion and Klenow DNA polymerases successfully accepted EBNA-T nucleotide as a substrate and yielded the fully extended DNA. KOD DNA polymerase was found to be the most efficient enzyme to furnish EBNA-T containing DNA in good yields. Phusion DNA polymerase efficiently amplified the template containing EBNA-T nucleotides by PCR.  相似文献   
43.
Phytochemical investigation of the n-butanol fraction of Evolvulus alsinoides (Linn.) led to the isolation of three new phenolic glycosides, evolvosides C, D and E (13) along with six known compounds (49). The structures of the compounds were elucidated on the basis of spectroscopic analysis, viz. 1D and 2D NMR experiments, chemical study, and comparison with literature data. Evolvoside C (1) was characterized as kaempferol 4′-O-β-d-glucopyranosyl-(1→2)-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside, whereas evolvosides D and E (23) were found to be mono and di-O-methyl derivatives of 1. The new compounds (1–3) represent rare triglycoside derivatives of flavonol at C-4′. The isolated compounds (16) were screened for acute stress-induced biochemical changes in male Sprague–Dawley rats at a dose of 40 mg/kg body weight. Compounds 1 and 2 displayed anti-stress effects by normalizing hyperglycemia, plasma corticosterone, plasma creatine kinase, and adrenal hypertrophy. Compounds 3 and 6 were also found to be effective in normalizing most of these stress parameters, whereas compounds 4 and 5 were ineffective in normalizing most of these effects.  相似文献   
44.
The TGF-b superfamily cytokine MIC-1/GDF15 circulates in all humans and when overproduced in cancer leads to anorexia/cachexia, by direct action on brain feeding centres. In these studies we have examined the role of physiologically relevant levels of MIC-1/GDF15 in the regulation of appetite, body weight and basal metabolic rate. MIC-1/GDF15 gene knockout mice (MIC-1−/−) weighed more and had increased adiposity, which was associated with increased spontaneous food intake. Female MIC-1−/− mice exhibited some additional alterations in reduced basal energy expenditure and physical activity, possibly owing to the associated decrease in total lean mass. Further, infusion of human recombinant MIC-1/GDF15 sufficient to raise serum levels in MIC-1−/− mice to within the normal human range reduced body weight and food intake. Taken together, our findings suggest that MIC-1/GDF15 is involved in the physiological regulation of appetite and energy storage.  相似文献   
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How sex is determined has been one of the most intriguing puzzles in biology since antiquity. Although a fundamental process in most metazoans, there seems to be myriad of ways in which sex can be determined – from genetic to environmental sex determination. This variation is limited mainly to upstream triggers with the core of sex determination pathway being conserved. Zebrafish has gained prominence as a vertebrate model system to study development and disease. However, very little is known about its primary sex determination mechanism. Here we review our current understanding of the sex determination in zebrafish. Zebrafish lack identifiable heteromorphic sex chromosomes and sex is determined by multiple genes, with some influence from the environment. Recently, chromosome 4 has been identified as sex chromosome along with few sex-linked loci on chromosomes 5 and 16. The identities of candidate sex-linked genes, however, have remained elusive. Sex in zebrafish is also influenced by the number of meiotic oocytes in the juvenile ovary, which appear to instruct retention of the ovarian fate. The mechanism and identity of this instructive signal remain unknown. We hypothesize that sex in zebrafish is a culmination of combinatorial effects of the genome, germ cells and the environment with inputs from epigenetic factors translating the biological meaning of this interaction.  相似文献   
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Molecular Biology Reports - Mulberry (Morus alba L.) is the sole food source for the mulberry silkworm, Bombyx mori and therefore important for sericulture industry. Different abiotic stress...  相似文献   
49.
5-HydroxyTriptamine 2A antagonists are potential targets for treatment of various cerebrovascular and cardiovascular disorders. In this study, we have developed and performed a unique screening pipeline for filtering ZINC database compounds on the basis of similarities to known antagonists to determine novel small molecule antagonists of 5-HydroxyTriptamine 2A. The screening pipeline is based on 2D similarity, 3D dissimilarity and a combination of 2D/3D similarity. The shortlisted compounds were docked to a 5-HydroxyTriptamine 2A homology-based model, and complexes with low binding energies (287 complexes) were selected for molecular dynamics (MD) simulations in a lipid bilayer. The MD simulations of the shortlisted compounds in complex with 5-HydroxyTriptamine 2A confirmed the stability of the complexes and revealed novel interaction insights. The receptor residues S239, N343, S242, S159, Y370 and D155 predominantly participate in hydrogen bonding. ππ stacking is observed in F339, F340, F234, W151 and W336, whereas hydrophobic interactions are observed amongst V156, F339, F234, V362, V366, F340, V235, I152 and W151. The known and potential antagonists shortlisted by us have similar overlapping molecular interaction patterns. The 287 potential 5-HydroxyTriptamine 2A antagonists may be experimentally verified.  相似文献   
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