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31.
Zhang J Li G Li Z Yu X Zheng Y Jin K Wang H Gong Y Sun X Teng X Cao J Teng L 《Steroids》2012,77(6):666-673
Estrogen receptor-alpha 36 (ER-α36) is a variant of ER-α that has been found to be expressed in conventional ER (ER-α66)-negative breast cancer cell lines and human breast cancer samples. In this study, we found that, using immunohistochemical study, ER-α36 expression was significantly higher in ER-negative tumors than in ER-positive tumors although the expression was not associated with other clinicopathological characteristics. We then constructed an ER-α36-specific microRNA hairpin vector and established stable ER-α36 knockdown cells, and found that the knockdown cells were more sensitive to paclitaxel; the c-Jun N-terminal kinase pathway appeared to be involved in the mechanism. Downregulation of ER-α36 also resulted in decreased migration and invasion. These changes were estrogen independent. Our findings indicated that target ER-α36 may be a strategy for treating ER-negative breast cancers. 相似文献
32.
Guangliang Pan Marc F. Verhagen Michael W. Adams 《Extremophiles : life under extreme conditions》2001,5(6):393-398
Pyridine-type nucleotides were identified in cell-free extracts of the hyperthermophilic archaeon Pyrococcus furiosus by their ability to replace authentic nicotinamide adenine dinucleotide (phosphate) [NAD(P)] in assays using pure P. furiosus enzymes. The nucleotides were purified using a combination of ion-exchange and reverse-phase chromatography. They were identified as NAD and NADP by analyses using liquid chromatography-mass spectrometry and high performance liquid chromatography. Their intracellular concentrations were measured in P. furiosus grown using maltose and peptides as the carbon sources. The concentrations decreased during the lag phase but remained constant during the exponential phase at approximately 0.17 and 0.13 mM, respectively. The amount of NAD was significantly lower (more than four-fold lower) than that in mesophilic bacteria, although the NADP concentration was comparable. The internal concentrations of NADH and NADPH in P. furiosus were determined to be 0.14 mM and 0.04 mM, respectively. The overall cellular concentration of NAD(P)(H) in P. furiosus (0.48 mM) is about half the value in the mesophiles. The NAD(H)/NADP(H) ratio in P. furiosus is consistent with the preferred use of NADP by several catabolic enzymes that have been purified from this organism. The mechanisms by which hyperthermophiles stabilize these thermally labile nicotinamide nucleotides are not known. 相似文献
33.
Accumulation of α-Keto Acids as Essential Components in Cyanide Assimilation by Pseudomonas fluorescens NCIMB 11764 下载免费PDF全文
Pyruvate (Pyr) and α-ketoglutarate (αKg) accumulated when cells of Pseudomonas fluorescens NCIMB 11764 were cultivated on growth-limiting amounts of ammonia or cyanide and were shown to be responsible for the nonenzymatic removal of cyanide from culture fluids as previously reported (J.-L. Chen and D. A. Kunz, FEMS Microbiol. Lett. 156:61–67, 1997). The accumulation of keto acids in the medium paralleled the increase in cyanide-removing activity, with maximal activity (760 μmol of cyanide removed min−1 ml of culture fluid−1) being recovered after 72 h of cultivation, at which time the keto acid concentration was 23 mM. The reaction products that formed between the biologically formed keto acids and cyanide were unambiguously identified as the corresponding cyanohydrins by 13C nuclear magnetic resonance spectroscopy. Both the Pyr and α-Kg cyanohydrins were further metabolized by cell extracts and served also as nitrogenous growth substrates. Radiotracer experiments showed that CO2 (and NH3) were formed as enzymatic conversion products, with the keto acid being regenerated as a coproduct. Evidence that the enzyme responsible for cyanohydrin conversion is cyanide oxygenase, which was shown previously to be required for cyanide utilization, is based on results showing that (i) conversion occurred only when extracts were induced for the enzyme, (ii) conversion was oxygen and reduced-pyridine nucleotide dependent, and (iii) a mutant strain defective in the enzyme was unable to grow when it was provided with the cyanohydrins as a growth substrate. Pyr and αKg were further shown to protect cells from cyanide poisoning, and excretion of the two was directly linked to utilization of cyanide as a growth substrate. The results provide the basis for a new mechanism of cyanide detoxification and assimilation in which keto acids play an essential role. 相似文献
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35.
Biomarkers indicate changes associated with disease. Blood is relatively stable due to the homeostatic mechanisms of the body;however, urine accumulates metabolites from changes in the body, making it a better source for early biomarker discovery. The Li ethnic group is a unique minority ethnic group that has only lived on Hainan Island for approximately 5,000 years. Studies have shown that various specific genetic variations are different between the Li and Han ethnic groups. However, whether the urinary proteome between these two ethnic groups is significantly different remains unknown. In this study, differential urinary proteins were identified in the Li and Han ethnic groups using liquid chromatography tandem mass spectrometry(LC-MS/MS).In total, 1,555 urinary proteins were identified. Twenty-five of the urinary proteins were statistically significantly different, 16 of which have been previously reported to be biomarkers of many diseases, and that these significantly different proteins were caused by ethnic differences rather than random differences. Ethnic group differences may be an influencing factor in urine proteome studies and should be considered when human urine samples are used for biomarker discovery. 相似文献
36.
Lian Gu Juanjuan Xie Jianxiong Long Qing Chen Qiang Chen Runde Pan Yan Yan Guangliang Wu Baoyun Liang Jinjing Tan Xinfeng Xie Bo Wei Li Su 《PloS one》2013,8(6)
Background
Major depressive disorder (MDD) is one of the important causes of disease burden in the general population. Given the experiencing rapid economic and social changes since the early 1990s and the internationally recognized diagnostic criteria and interview instruments across the surveys during 2001–2010 in china, the epidemiological studies on MDD got varied results. We performed this meta-analysis to investigate current, 12-month and lifetime prevalence rates of MDD in mainland China.Methods
PubMed, Embase, Chinese Biological Medical Literature database (CBM), Chinese National Knowledge Infrastructure database (CNKI), and the Chinese Wanfang and Chongqing VIP database were searched for associated studies. We estimated the overall prevalence of MDD using meta-analysis.Conclusions
Seventeen eligible studies were included. Our study showed that the overall estimation of current, 12-month and lifetime prevalence of MDD was 1.6, 2.3, 3.3%, respectively. The current prevalence was 2.0 and 1.7% in rural and urban areas, respectively; between female and male, it was 2.1 and 1.3%, respectively. In addition, the current prevalence of MDD diagnosed with SCID (Structured Clinical Interview for DSM-IV) was 1.8% and that diagnosed with CIDI (Composite International Diagnostic Interview) was 1.1%. In conclusion, our study revealed a relatively high prevalence rate in the lifetime prevalence of MDD. For current prevalence, MDD diagnosed with SCID had a higher prevalence rate than with CIDI; males showed a lower rate than females, rural residents seemed to have a greater risk of MDD than urban residents. 相似文献37.
Yufeng Yin Di Liang Lidan Zhao Yang Li Wei Liu Yan Ren Yongzhe Li Xiaofeng Zeng Fengchun Zhang Fulin Tang Guangliang Shan Xuan Zhang 《PloS one》2014,9(4)
Objective
Patients with rheumatoid arthritis (RA) are at risk to develop RA-associated interstitial lung disease (RA-ILD). This retrospective study aimed to investigate the potential association of the positivity of serum anti-cyclic citrullinated peptide antibody (anti-CCP2) and rheumatoid factor (RF) with RA-ILD in RA patients.Methods
A total of 285 RA patients were recruited at the inpatient service of Peking Union Medical College Hospital in China between 2004 and 2013. Individual patients were evaluated for the evidence of ILD. The concentrations of serum anti-CCP2 and RF in individual patients were measured. The potential risk factors for ILD in RA patients were assessed by univariate and multivariate models.Results
There were 71 RA patients with RA-ILD, accounting for 24.9% in this population. The positive rates of anti-CCP2 and RF in the patients with RA-ILD were significantly higher than that in the patients with RA-only (88.7% vs. 67.3%, p<0.001; 84.5% vs. 70.6%, p = 0.02, respectively). Univariate and multivariate logistic regression analysis revealed that RA patients with positive serum anti-CCP2, but not RF, were associated with an increased risk of ILD (crude odds ratio [cOR] 3.83, 95% confidence interval [CI] 1.74–8.43, p<0.001; adjusted odds ratio [aOR] 3.50, 95% CI 1.52–8.04, p<0.001).Conclusion
Our findings suggest that positive serum anti-CCP2, but not RF, may be associated with RA-ILD in RA patients. 相似文献38.
39.
Laibin Huang Junhong Bai Xiaojun Wen Guangliang Zhang Chengdong Zhang Baoshan Cui Xinhui Liu 《Global Change Biology》2020,26(4):2377-2389
With the increasing intensity of global human activities, the ecosystem function, which is supported by the microbial community, will be dramatically changed and impaired. To investigate microbial resistance and resilience of microbial communities to human activities, we chose two typical types of human disturbances, urbanization, and reclamation under the higher intensity of human activities than the global average level. We examined microbial traits, including the abundance, diversity, phylogeny, and co‐occurrence interactions in soil microbial communities, together with the nitrification activities observed in the subtropical coastal ecosystem of the Pearl River Estuary and in soil microcosm experiments. Microbial communities were less resistant to the environmental changes caused by urbanization than to those caused by reclamation, which was significantly reflected in the nitrogen and/or carbon‐related patterns. However, most of the microbial traits could be recovered almost to the original level without significant differences in the microcosm after 40 days of incubation. The co‐occurrence interactions between nitrifiers and other microbial communities were dramatically changed and could not be completely recovered, but this change did not affect their nitrification activities for balancing the ammonium in the soil to the original level during the recovery stage, suggesting that the interactions between microbial communities might have fewer effects on their activities than previously thought. This study quantitatively demonstrated that microbial communities as a whole can recover to a status similar to the original state in a short time after the removal of stress at a large ecosystem scale even under the higher intensity of human activities than global average level in coastal ecosystems, which implied a strong recovery capacity of soil microbial community even after intense human disturbance. 相似文献
40.
The FLASH and STEAM pulse sequences were used to perform the microimaging and localized spectroscopy of brain of living and dead mice, respectively. The phase-shift presaturation approach was used to sup-press water NMR signal. The experimental results show that the differences in localized spectra and MR images of brain between live and dead mice can be observed by means of magnetic resonance microscopy. 相似文献