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21.
Molecular Biology Reports - We studied to ascertain whether the ACE and/or CKMM genotypes independently influence the baseline level of some sport performances in 613 inactive male adolescents...  相似文献   
22.
Colorectal cancer (CRC) is the leading cause of cancer death worldwide. Dysregulation of RAS/MAPK signaling axis is frequently found in CRC patients. The RAS/MAPK axis regulates cancer cell proliferation, apoptosis, inflammation, migration, and metastasis. Oncogenic or tumor-suppressor microRNAs (miRNAs) for RAS/MAPK signaling play a key role in the pathogenesis of CRC and are considered as novel potential biomarkers for diagnosis and prognosis of human malignancies. This review summarizes the current knowledge of mechanisms of action of RAS/MAPK miRNAs in the development and progression of CRC for a better understanding and hence a better management of this disease.  相似文献   
23.
Two detergent stable alkaline serine-proteases (BM1 and BM2) from Bacillus mojavensis A21 were purified. The molecular weights of BM1 and BM2 enzymes determined by SDS–PAGE were approximately 29,000 Da and 15,500 Da, respectively. The optimum pH values of BM1 and BM2 proteases were shown to be 8.0–10.0 and 10.0, respectively. Both enzymes exhibited maximal activity at 60 °C, using casein as a substrate.  相似文献   
24.

Background  

β-catenin is an essential mediator of canonical Wnt signaling and a central component of the cadherin-catenin epithelial adhesion complex. Dysregulation of β-catenin expression has been described in pancreatic neoplasia. Newly published studies have suggested that β-catenin is critical for normal pancreatic development although these reports reached somewhat different conclusions. In addition, the molecular mechanisms by which loss of β-catenin affects pancreas development are not well understood. The goals of this study then were; 1] to further investigate the role of β-catenin in pancreatic development using a conditional knockout approach and 2] to identify possible mechanisms by which loss of β-catenin disrupts pancreatic development. A Pdx1-cre mouse line was used to delete a floxed β-catenin allele specifically in the developing pancreas, and embryonic pancreata were studied by immunohistochemistry and microarray analysis.  相似文献   
25.
Molecular Biology Reports - In this study, the optimized niosomal formulation containing paclitaxel using non-ionic surfactants and cholesterol was designed and its cytotoxic effects against...  相似文献   
26.
Precise timing of sperm activation ensures the greatest likelihood of fertilization. Precision in Caenorhabditis elegans sperm activation is ensured by external signaling, which induces the spherical spermatid to reorganize and extend a pseudopod for motility. Spermatid activation, also called spermiogenesis, is prevented from occurring prematurely by the activity of SPE-6 and perhaps other proteins, termed “the brake model.” Here, we identify the spe-47 gene from the hc198 mutation that causes premature spermiogenesis. The mutation was isolated in a suppressor screen of spe-27(it132ts), which normally renders worms sterile, due to defective transduction of the activation signal. In a spe-27(+) background, spe-47(hc198) causes a temperature-sensitive reduction of fertility, and in addition to premature spermiogenesis, many mutant sperm fail to activate altogether. The hc198 mutation is semidominant, inducing a more severe loss of fertility than do null alleles generated by CRISPR-associated protein 9 (Cas9) technology. The hc198 mutation affects an major sperm protein (MSP) domain, altering a conserved amino acid residue in a β-strand that mediates MSP–MSP dimerization. Both N- and C-terminal SPE-47 reporters associate with the forming fibrous body (FB)-membranous organelle, a specialized sperm organelle that packages MSP and other components during spermatogenesis. Once the FB is fully formed, the SPE-47 reporters dissociate and disappear. SPE-47 reporter localization is not altered by either the hc198 mutation or a C-terminal truncation deleting the MSP domain. The disappearance of SPE-47 reporters prior to the formation of spermatids requires a reevaluation of the brake model for prevention of premature spermatid activation.  相似文献   
27.
A protocol was established for callus induction and plant regeneration of Albizia julibrissin Durazz., a multipurpose tree. Calli were induced on hypocotyl explants excised from 10- to 14-d-old in vitro seedlings cultured on Murashige and Skoog (MS) medium supplemented with α-naphthaleneacetic acid (NAA) alone or in combination with 6-benzylaminopurine (BA) or 6-furfurylaminopurine (kinetin). The highest frequency of organogenic callus (82.2?±?3.6%) was obtained on MS medium with 10.8 μM NAA and 4.4 μM BA. Calli were then cultured on MS medium with BA or zeatin, singly or in combination, for shoot regeneration. Calli cultured on MS medium with 13.2 μM BA and 4.6 μM zeatin produced the highest frequency of adventitious shoot regeneration (75.3?±?6.3%). Maximum rooting of shoots (73.3?±?5%) was achieved using half-strength MS medium with 4.9 μM indole-3-butyric acid. The genetic fidelity of 12 plants acclimatized to the greenhouse was assessed based on analyses of start codon targeted (SCoT) polymorphism and inter-retrotransposon amplified polymorphism (IRAP). The 14 SCoT and 7 IRAP adapted primers produced 71 and 34 scoreable fragments, of which 33 (46%) and 12 (35%) were polymorphic, respectively. The in vitro-raised plants exhibited 0.129–0.438 genetic distance from the mother plant and 0.000–0.788 distance from one another according to the SCoT and IRAP analyses. Although the culture method described here may not be suitable for clonal propagation of elite genotypes, it can be used for conservation of this plant.  相似文献   
28.
Poly(3-hydroxybutyrate-co-38 mol%-3-hydroxyvalerate) [P(3HB-co-38mol%-3HV)] was produced by Cupriavidus sp. USMAA2-4 in the presence of oleic acid and 1-pentanol. Due to enormous production of empty fruit bunch (EFB) in the oil palm plantation and high production cost of P(3HB-co-3HV), oil palm EFB fibers were used for biocomposites preparation. In this study, maleic anhydride (MA) and benzoyl peroxide (DBPO) were used to improve the miscibility between P(3HB-co-3HV) and EFB fibers. Introduction of MA into P(3HB-co-3HV) backbone reduced the molecular weight and improved the thermal stability of P(3HB-co-3HV). Thermal stability of P(3HB-co-3HV)/EFB composites was shown to be comparable to that of commercial packaging product. Composites with 35% EFB fibers content have the highest tensile strength compared to 30% and 40%. P(3HB-co-3HV)/EFB blends showed less chemicals leached compared to commercial packaging.  相似文献   
29.
β-Casein is one of the major components of the milk micelles of most mammals and has been shown to exhibit in vitro chaperone-like activity. Glycerol is a chemical chaperone belonging to the polyol family, which increases protein stability and inhibits protein aggregation. These prompted us to compare the chaperone-like activity of β-casein and glycerol. In this study, the effect of β-casein and glycerol on folding of the target proteins (ovotransferrin, insulin and α-lactalbumin) in the presence of dextran, as a macromolecular crowding agent, is examined using visible absorption spectroscopy, intrinsic fluorescence spectroscopy, 1-anilino-8-naphthalene sulfonic acid fluorescence binding and near CD spectroscopy. In the presence of dextran, the rate and extent of aggregation of target proteins was enhanced and β-casein was less effective in preventing the aggregation and precipitation of target proteins. These data support the hypothesis that β-casein interacts more effectively with slowly aggregating rather than rapidly aggregating target proteins. It is proposed that dextran-induced changes to protein conformation and the rate of intermolecular association are in a kinetic competition with the chaperoning action of β-casein; however our results demonstrated the higher activity of glycerol, as a chemical chaperone, than β-casein on the folding of target proteins, especially in the presence of dextran. This is likely due to the stabilizing effect of glycerol on protein structure and environment. The implications for the in vivo functions of β-casein and glycerol, based on their exhibiting such in vitro chaperone-like activities, are discussed.  相似文献   
30.
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