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Guo Hongwei Huang Tianqiu Zhao Jun Chen Hongwen Chen Guo 《Applied microbiology and biotechnology》2018,102(11):4653-4662
Applied Microbiology and Biotechnology - Short-chain carboxylic acids and their derivatives are widely utilized in all aspects of our daily life. Given their specific functional groups, these... 相似文献
84.
Novel biomarkers for cancer diagnosis and therapy selection are urgently needed to facilitate early detection and improve therapy outcomes. We have previously identified a novel phosphorylation site at serine 506 (PS506) on topoisomerase-I (topo-I) and have shown that it is widely expressed in cell lines derived from several cancers, including lung cancer, but is low in cell lines derived from non-cancerous tissues. Here we have investigated how PS506 expression in lung tissue specimens correlates with their malignant status. We find that PS506 expression is significantly elevated in malignant tumors of non-small cell lung cancer (NSCLC) compared to adjacent, non-cancerous lung tissue and benign lung tumors. PS506 expression was up to 6-fold higher in malignant specimens than in paired non-malignant tissue. Using the well-characterized NIH/NCI 60-cell line panel, we correlate the most elevated expression levels of PS506 in lung, ovarian, and colon cancer cells lines with increased sensitivity to camptothecin, a plant alkaloid that targets topo-I. This is consistent with our earlier studies in a smaller sampling of cell lines and with our finding that PS506 increases topo-I DNA binding. Two widely used chemotherapeutic drugs for ovarian and colon cancer, topotecan and irinotecan, respectively, are derived from camptothecin. Irinotecan has also displayed efficacy in clinical trials of NSCLC. Our results suggest that elevated PS506 expression may correlate with clinical chemosensitivity to these agents in ovarian, colon, and NSCLC. PS506 may therefore serve as a biomarker for diagnosis or therapy selection. 相似文献
85.
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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One new genus of the spider subfamily Coelotinae, Flexicoelotes
gen. n., with five new species is described from southern China: Flexicoelotes
huyunensis
sp. n. (female), Flexicoelotes
jiaohanyanensis
sp. n. (male and female), Flexicoelotes
jinlongyanensis
sp. n. (male and female), Flexicoelotes
pingzhaiensis
sp. n. (female), Flexicoelotes
xingwangensis
sp. n. (male and female). 相似文献
88.
Carpooling is an effective means of reducing traffic. A carpool team shares a vehicle for their commute, which reduces the number of vehicles on the road during rush hour periods. Carpooling is officially sanctioned by most governments, and is supported by the construction of high-occupancy vehicle lanes. A number of carpooling services have been designed in order to match commuters into carpool teams, but it known that the determination of optimal carpool teams is a combinatorially complex problem, and therefore technological solutions are difficult to achieve. In this paper, a model for carpool matching services is proposed, and both optimal and heuristic approaches are tested to find solutions for that model. The results show that different solution approaches are preferred over different ranges of problem instances. Most importantly, it is demonstrated that a new formulation and associated solution procedures can permit the determination of optimal carpool teams and routes. An instantiation of the model is presented (using the street network of Guangzhou city, China) to demonstrate how carpool teams can be determined. 相似文献
89.
Xingyu Zhu Qianqian Gao Genhua Zhao Heng Wang Ling Liu Zhipeng Chen Yijun Chen Li Wu Zisheng Xu Weidong Li 《Biological trace element research》2018,184(1):136-147
To evaluate and compare the effect of raw and processed pyritum on tibial defect healing, 32 male Sprague Dawley rats were randomly divided into four groups. After tibial defect, animals were produced and grouped: sham and control group were orally administrated with distilled water (1 mL/100 g), while treatment groups were given aqueous extracts of raw and processed pyritum (1.5 g/kg) for successive 42 days. Radiographic examination showed that bone defect healing effect of the treatment groups was obviously superior compared to that of the control group. Bone mineral density of whole tibia was increased significantly after treating with pyritum. Inductively coupled plasma-optical emission spectrometry showed that the contents of Ca, P, and Mg in callus significantly increased in the treatment groups comparing with the control. Moreover, serological analysis showed that the concentration of serum phosphorus of the treatment groups significantly increased compared with that of the control group. By in vitro study, we have evaluated the effects of drug-containing serum of raw and processed pyritum on osteoblasts. It was manifested that both the drug-containing sera of raw and processed pyritum significantly increased the mRNA levels of alkaline phosphatase and collagen type I. Protein levels of phosphorylated Smad2/3 also increased. The mRNA levels of osteocalcin and transforming growth factor β (TGF-β) type I and II receptors, as well as the protein levels of TGF-β1 in the processed groups, were higher than those in the control. In summary, both raw and processed pyritum-containing sera exhibited positive effects on osteoblasts, which maybe via the TGF-β1/Smad signaling pathway. Notably, the tibia defect healing effect of pyritum was significantly enhanced after processing. 相似文献
90.