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441.
For the rabphillin-3A-like (RPH3AL) gene, a putative tumor suppressor, the clinical significance of genetic alterations in breast cancers was evaluated. DNA and RNA were extracted from formalin-fixed, paraffin-embedded (FFPE) cancers and matching normal tissues. DNA samples were assessed for loss of heterozygosity (LOH) at the 17p13.3 locus of RPH3AL and the 17p13.1 locus of the tumor suppressor, TP53. RPH3AL was sequenced, and single nucleotide polymorphisms (SNPs) were genotyped. RNA samples were evaluated for expression of RPH3AL, and FFPE tissues were profiled for its phenotypic expression. Alterations in RPH3AL were correlated with clinicopathological features, LOH of TP53, and patient survival. Of 121 cancers, 80 had LOH at one of the RPH3AL locus. LOH of RHP3AL was associated with nodal metastasis, advanced stage, large tumor size, and poor survival. Although ~50% were positive for LOH at the RPH3AL and TP53 loci, 19 of 105 exhibited LOH only at the RPH3AL locus. Of these, 12 were non-Hispanic Caucasians (Whites), 15 had large tumors, and 12 were older (>50 years). Patients exhibiting LOH at both loci had shorter survival than those without LOH at these loci (log-rank, P = 0.014). LOH at the TP53 locus alone was not associated with survival. Analyses of RPH3AL identified missense point mutations in 19 of 125 cases, a SNP (C>A) in the 5’untranslated region at -25 (5’UTR-25) in 26 of 104, and a SNP (G>T) in the intronic region at 43 bp downstream to exon-6 (intron-6-43) in 79 of 118. Genotype C/A or A/A of the SNP at 5’UTR-25 and genotype T/T of a SNP at intron-6-43 were predominantly in Whites. Low levels of RNA and protein expression of RPH3AL were present in cancers relative to normal tissues. Thus, genetic alterations in RPH3AL are associated with aggressive behavior of breast cancers and with short survival of patients.  相似文献   
442.
TPM1κ is an alternatively spliced isoform of the TPM1 gene whose specific role in cardiac development and disease is yet to be elucidated. Although mRNA studies have shown TPM1κ expression in axolotl heart and skeletal muscle, it has not been quantified. Also the presence of TPM1κ protein in axolotl heart and skeletal muscle has not been demonstrated. In this study, we quantified TPM1κ mRNA expression in axolotl heart and skeletal muscle. Using a newly developed TPM1κ specific antibody, we demonstrated the expression and incorporation of TPM1κ protein in myofibrils of axolotl heart and skeletal muscle. The results support the potential role of TPM1κ in myofibrillogenesis and sarcomeric function. J. Cell. Biochem. 110: 875–881, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
443.
The beneficial effect of garlic on cardiovascular disease is well known. However, the use of raw garlic against cardiac hypertrophy is not established. In the present study we explored whether raw garlic and its compound, diallyl disulfide (DADS) could inhibit hypertrophy through H2S and/or mitochondrial biogenesis. Cardiac hypertrophy was induced in rat by giving isoproterenol at the dose of 5 mg/kg/day subcutaneously for 14 days through alzet minipump. Aqueous garlic homogenate, DADS and NaHS (liberate H2S) were fed to third, forth and fifth group of rats for 14 days at a dose of 250 mg/kg/day, 50 mg/kg/day, 14 µM/kg/day respectively. Garlic and DADS reduced cardiac hypertrophy markers and normalized mitochondrial ETC-complex activities, mitochondrial enzyme activites and mitochondrial biogenetic and apoptotic genes expression. Garlic and DADS enhanced eNOS and p-AKT level in rat heart along with increased NRF2 protein level and Tfam gene expression. However, normalization was not observed after administration of NaHS which generates H2S in-vivo. In conclusion, garlic and DADS induces mitochondrial biogenesis and ameliorates cardiac hypertrophy via activation of eNOS-Nrf2-Tfam pathway in rats.  相似文献   
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Bioactivity-guided separation of an antihyperglycemic extract from the leaves of Dodecadenia grandiflora afforded two phenylpropanoyl esters of catechol glycosides (1 and 4) and two lignane bis(catecol glycoside)esters (2 and 3). Their structures were established on the basis of extensive spectroscopic analysis (1D and 2D-NMR, MS). Compounds 2 and 3 are believed to be derived from dimerization via the two phenylpropanoid units of 1. Compounds 1–4 showed significant antihyperglycemic activity in streptozotocin-induced (STZ) diabetic rats, which is comparable to the standard drug metformin. Our results provide support to explain the use of D. grandiflora as antihyperglycemic agent by the traditional medical practitioners.  相似文献   
446.
Present study was conducted to analyze bacterial contaminants /pathogens in Khoa samples sold in Chambal region of Madhya Pradesh. Total Fifty samples of Khoa were brought from different localities of Chambal region at random and processed. Bacterial colony counts were also performed. Staphylococcus species and Streptococcus species were the predominant isolates. The viable counts obtained ranged from 1.3sX104 to 2.1sX106 CFU/g. Contamination of Khoa by pathogenic bacteria could be an important factor of gastrointestinal infections including food poisoning and food borne illness. Adequate consumer protection can be achieved by measuring the microbiological data of product.  相似文献   
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Isolation of two keratinolytic bacterial strains from poultry soil as well as purification and properties of keratinase were investigated. Isolates were designated as KI8101 and KI8102 (KI, keratin isolates) and were identified as Bacillus subtilis and B. licheniformis respectively. The purified enzyme from KI8102 exhibited a high specific activity of 500 U/mg with 71‐fold purification and 41% yield. SDS‐PAGE analysis indicated that the purified keratinase had a molecular mass of 32 kDa. The optimum temperature and pH were 50°C and 7.5, respectively. Its Km was 83.3 μM and Vmax was 71.4 μmol/mL min. The bacterium could potentially degrade keratin waste such as human hair, nails, bovine hair and wool. Therefore, the enzyme could improve the nutritional value of meat and poultry‐processing waste containing keratin and could be a potential candidate for biotechnological processing involving keratin hydrolysis.  相似文献   
449.
Natural products for cancer chemotherapy   总被引:1,自引:0,他引:1  
For over 40 years, natural products have served us well in combating cancer. The main sources of these successful compounds are microbes and plants from the terrestrial and marine environments. The microbes serve as a major source of natural products with anti‐tumour activity. A number of these products were first discovered as antibiotics. Another major contribution comes from plant alkaloids, taxoids and podophyllotoxins. A vast array of biological metabolites can be obtained from the marine world, which can be used for effective cancer treatment. The search for novel drugs is still a priority goal for cancer therapy, due to the rapid development of resistance to chemotherapeutic drugs. In addition, the high toxicity usually associated with some cancer chemotherapy drugs and their undesirable side‐effects increase the demand for novel anti‐tumour drugs active against untreatable tumours, with fewer side‐effects and/or with greater therapeutic efficiency. This review points out those technologies needed to produce the anti‐tumour compounds of the future.  相似文献   
450.
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