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991.
Background This study attempts to understand the association of candidate tumour suppressor genes SH3GL2, CDKN2A (p16–p14) and CDKN2B (p15) in development of early-onset (group A) and late-onset (group B) breast carcinoma (BC). Methods Deletion, methylation, and mutation of the candidate tumour suppressor genes (TSGs) were analysed in 47 group A and 59 group B samples. Immunohistochemical analysis was used to identify the expression status of SH3GL2 and p16. Clinicopathological correlation of the alterations was analysed by the chi-square and log-rank tests. Results Higher frequency of overall alterations (46–62%) in SH3GL2 and p16-p14 than p15 (22–26%) indicated their importance in BC. Deletion frequencies were in the following order: group A: p14 (43%) > p16 (42%) > SH3GL2 (38%) > p15 (33%) and group B: p14 (36%) > p16 (33%) > SH3GL2 (31%) > p15 (14%) while, methylation frequencies were: group A: SH3GL2 (34%) > p16 (28%) > p14 (26%) > p15 (15%) and group B: SH3GL2 (36%) > p16 (31%) > p14 (29%) > p15 (15%). Infrequent mutation was observed only in CDKN2A common exon-2. Immunohistochemical analysis showed significant association between expression of SH3GL2 and p16 with their deletion (P = 0.01 and 0.02, respectively) and methylation status (P = 0.007 and 0.01, respectively). In group A, overall alterations of SH3GL2 showed significant association with CDKN2A locus with significant prognostic implications, whereas CDKN2A and CDKN2B loci were associated in both groups. Conclusions The molecular mechanisms involving CDKN2A inactivation seem to follow similar pathway in the pathogenesis of both age groups of BC while significant association of SH3GL2 with CDKN2A might play a synergistic role in the development of group A.  相似文献   
992.
Supercritical fluid chromatography (SFC) is increasingly being recognized as a powerful technique for analysis of pharmaceutical compounds in various dosage forms. Assay of aqueous formulations of research compounds by SFC is, however, a relatively unexplored area primarily due to the potential problems associated with it. This work describes the development of a direct assay of a chiral drug compound AZY in a 100% aqueous formulation by SFC, and its qualification following ICH and FDA validation guidelines on chromatographic methods. The results indicated that SFC has the potential for assaying aqueous formulations of research compounds with high degree of selectivity, accuracy, precision, robustness, sensitivity, and linearity over a wide range of concentrations. This work also confirmed a previous hypothesis that direct formulation assay by SFC approach is applicable to both acidic and basic pharmaceutical compounds with equal degree of success.  相似文献   
993.
Epithelioid angiosarcomas of the aorta are extremely rare neoplasms with only 26 previous reports in the literature. An extremely unusual case is reported of an aortic epithelioid angiosarcoma diagnosed in a 47-year-old man who was being evaluated for his rectal adenocarcinoma. This case prompted a review of literature for aortic intimal neoplasms. No previous reports of a synchronous aortic angiosarcomas and adenocarcinomas of the colorectum have been reported. Even though the occurrence of the aortic intimal neoplasia and rectal cancer in this patient is most likely coincidental, the onset of this disease in a young man without risk factors for either disease probably suggests a genetic basis of his disease.  相似文献   
994.
995.
Lapatinib is a dual (ErbB-1 and ErB-2) receptor tyrosine kinase inhibitor (TKI) that was recently approved by the FDA for the treatment of advanced breast cancer. It shows synergy with trastuzumab, and has demonstrated clinical activity in trastuzumab-resistant tumour. This paper reviews the drug development of lapatinib from preclinical studies to the pivotal Phase III trial and ongoing clinical studies. Areas of interest include the advantages of small molecule TKIs versus antibodies in targeting HER receptors and the efficacy of lapatinib in the treatment of cerebral metastases. The surprisingly high response rate in inflammatory breast cancer raises the possibility of other novel predictive biomarkers. The potential for combination and sequencing with other biological and cytotoxic agents is both exciting and challenging.  相似文献   
996.
This study was to examine whether skeletal health deterioration in the hypogonadal situation is a consequence of an alteration in the functional status of peripheral mononuclear cells and its amelioration, if any, by an oil extract of garlic. The results suggest that hypogonadism-induced oxidative stress of peritoneal macrophages and lymphocytes could be reduced by supplementation with an oil extract of garlic. However, estrogen deficiency did not cause any significant change in DNA fragmentation of peritoneal macrophages. The hypogonadism-induced increase in the serum levels of IL-6 and TNF-alpha were significantly reduced by an oil extract of garlic. Further, such supplementation could revive the hypogonadism-induced decrease in serum estrogen titer and counter-balance the increase in bone turnover as determined by low bone tensile strength and alterations in bone related biochemical variables such as urinary calcium, hydroxyproline, calcium to creatinine ratio and serum tartrate resistant acid phosphatase activity (TRAP). The garlic oil supplemented partial recovery of the serum estrogen titer in hypogonadal rats was found to be persistently associated with reduced oxidative stress of peritoneal macrophages and lymphocytes, reduced serum interleukins and better preservation of bone mass. This study proposes that the hypogonadism-induced bone loss has a direct correlation with the functional status of lymphocytes and peritoneal macrophages, and garlic can prevent this.  相似文献   
997.
The cholinergic hypothesis of Alzheimer's disease (AD) has provided the rationale for the current pharmaco-therapy of this disease, in an attempt to reduce the cognitive decline caused by cholinergic deficits. Nevertheless, the search for potent and long-acting acetylcholinesterase (AChE) inhibitors that exert minimal side effects in AD patients is still ongoing. AChE inhibitors are currently the only approved therapy for the treatment of Alzheimer's disease; only a limited number of drugs are commercially available. Hydroalcohol extracts of six herbs, Andrographis paniculata, Centella asiatica, Evalvulus alsinoides, Nardostachys jatamansi, Nelumbo nucifera, Myristica fragrans used in Indian systems of medicine, were tested for in vitro acetylcholinesterase inhibitory activity based on Ellman's method in 96-well microplates using AChE obtained from bovine erythrocytes. The results showed that the hydroalcohol extract from Centella asiatica, Nardostachys jatamansi, Myristica fragrans, Evalvulus alsinoides inhibited 50% of AChE activity at concentrations of 100-150 microg/mL. Andrographis paniculata and Nelumbo nucifera extracts showed a weak inhibition of acetylcholinesterase with IC(50) values of 222.41 +/- 19.87 microg/mL and 185.55 +/- 21.24 microg/mL, respectively. Physostigmine was used as a standard and showed inhibition of acetylcholinesterase with an IC(50) value of 0.076 +/- 0.0042 microg/mL.  相似文献   
998.
Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals-sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significant (P<0.05) concentration-dependent increases in DNA damage in whole blood cells, lymphocytes, and in Nicotiana plants. The comet parameters show increases in tail DNA percentage (%), tail length (mum), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations.  相似文献   
999.
The purpose of this study was to determine the efficacy of amphotericin B lipid complex (ABLC) against Candida albicans biofilms using a rabbit model of catheter-associated candidal biofilm. A clinical C. albicans isolate was allowed to form biofilms on catheters placed in vivo and was then exposed to lock therapy with ABLC (1.5mg, locked for 4h or 8h for 7 days). Untreated biofilms served as controls. Fungal loads on the proximal and distal sections of catheters were determined by counting colony-forming units (CFUs), whilst surface architecture of formed biofilms was evaluated by scanning electron microscopy (SEM). Studies revealed that all ABLC-treated catheters were sterilised and yielded 0 CFU (P相似文献   
1000.
The presence of class 1 integrons in multiple-antibiotic-resistant (MAR) Gram-negative copiotrophic bacteria from the River Torsa in India was detected using a polymerase chain reaction (PCR)-based screening method. Among 100 isolates that were resistant to at least five of the twelve antibiotics tested, 40 carried class 1 integrons, with inserted DNA regions of 0.7-3.2 kb. Carriage of integrons in strains of higher MAR index was found to be statistically significant. DNA sequencing was used to identify the genetic content of the integron-variable regions. In addition to the identification of gene cassettes dfrA1, dfrA5, dfrA7, dfrA17 and a variant of dfrA12 for trimethoprim, aac(6')-Ib for amikacin and tobramycin and aadA1 and aadA6 for streptomycin and spectinomycin resistance, a novel ORF predicted from a sequence of Morganella sp. TR 90 bearing homology with the Vibrio cholerae dfrA1 gene cassette was characterized. To our knowledge, this is the first report of the incidence and abundance of class 1 integrons in copiotrophic river water bacteria from India.  相似文献   
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