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Mitochondrial DNA (mtDNA) copy number in peripheral blood has been suggested as risk modifier in various types of cancer. However, its influence on melanoma risk is unclear. We evaluated the association between mtDNA copy number in peripheral blood and melanoma risk in 500 melanoma cases and 500 healthy controls from an ongoing melanoma study. The mtDNA copy number was measured using real-time polymerase chain reaction. Overall, mean mtDNA copy number was significantly higher in cases than in controls (1.15 vs 0.99, P<0.001). Increased mtDNA copy number was associated with a 1.45-fold increased risk of melanoma (95% confidence interval: 1.12-1.97). Significant joint effects between mtDNA copy number and variables related to pigmentation and history of sunlight exposure were observed. This study supports an association between increased mtDNA copy number and melanoma risk that is independent on the known melanoma risk factors (pigmentation and history of sunlight exposure). 相似文献
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In a continuing study of microbial secondary metabolism in
simulated microgravity, we have examined gramicidin S (GS) production by
Bacillus brevis strain Nagano in NASA High Aspect Rotating Vessels
(HARVs), which are designed to simulate some aspects of microgravity. Growth
and GS production were found to occur under simulated microgravity. When
performance under simulated microgravity was compared with that under normal
gravity conditions in the bioreactors, GS production was found to be
unaffected by simulated microgravity. The repressive effect of glycerol in
flask fermentations was not observed in the HARV. Thus the negative effect of
glycerol on specific GS formation is dependent on shear and/or vessel
geometry, not gravity.
Received: 7 August 1996 / Accepted: 17 September 1996 相似文献
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Jiefeng He Haichao Zhao Dongfeng Deng Yadong Wang Xiao Zhang Haoliang Zhao Zongquan Xu 《Journal of cellular physiology》2020,235(3):2464-2477
This study aimed to identify significant biomarkers related to the prognosis of liver cancer using long noncoding RNA (lncRNA)-associated competing endogenous RNAs (ceRNAs) analysis. Differentially expressed mRNA and lncRNAs between liver cancer and paracancerous tissues were screened, and the functions of these mRNAs were predicted by gene ontology and pathway enrichment analyses. A ceRNA network consisting of differentially expressed mRNAs and lncRNAs was constructed. LncRNA FENDRR and lncRNA HAND2-AS1 were hub nodes in the ceRNA network. A risk score assessment model consisting of eight genes (PDE2A, ESR1, FBLN5, ALDH8A1, AKR1D1, EHHADH, ADRA1A, and GNE) associated with prognosis were developed. Multivariate Cox regression suggested that both pathologic_T and risk group could be regarded as independent prognostic factors. Furthermore, a nomogram model consisting of pathologic_T and risk group showed a good prediction ability for predicting the survival rate of liver cancer patients. The nomogram model consisting of pathologic_T and a risk score assessment model could be regarded as an independent factor for predicting prognosis of liver cancer. 相似文献
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Introducing chimeric antigen receptor into immune cells against malignancies has contributed to a revolutionary innovation in cancer immunotherapy. As an important type of adaptive immune cells, T cells first caught researchers' attention and became great success in chimeric antigen receptor-based immunotherapy. However, engineered T cells seem to hit their bottleneck when resistance of cancerous cells, less encouraging responses in solid tumors and unwanted toxicities to the host remain to be solved.Meanwhile, innate immune cells get to join the race. Representatives such as natural killer cells, natural killer T cells, γδT cells and macrophages also prove to be well redirected with chimeric antigen receptors. Compared to chimeric antigen receptor engineered T cells, these engineered innate immune cells may possess multiple targeting and killing mechanisms, have the potential to crack the barrier of solid tumors and have less side effects in the host. Besides, possible universal access to cell resources and improvements in expansion and transduction techniques make these cells promising candidates with huge potential in translational medicine. Therefore, innate immune cells claim a brand-new dimension and are likely to supplement T cells greatly in the field of chimeric antigen receptor-based immunotherapy. 相似文献
80.
<正>Aristolochic acids, mutational signature, and hepatocellular carcinoma Aristolochic acids (AA) are the etiologic agents of aristolochic acid nephropathy (AAN) and contribute to the global prevalence of chronic kidney disease and urothelial cancer (Grollman et al., 2007). DNA adducts formed by AA generate a unique AT transversions mutation spectrum at 相似文献