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101.
Kim DM Yun NR Neupane GP Shin SH Ryu SY Yoon HJ Wie SH Kim WJ Lee CY Choi JS Yang TY 《PloS one》2011,6(8):e22731
Background
Scrub typhus is an infectious disease caused by Orientia tsutsugamushi. The differences in virulence of O. tsutsugamushi prototypes in humans are still unknown. We investigated whether there are any differences in the clinical features of the Boryoung and Karp genotypes.Methodology/Principal Findings
Patients infected with O. tsutsugamushi, as Boryoung and Karp clusters, who had visited 6 different hospitals in southwestern Korea were prospectively compared for clinical features, complications, laboratory parameters, and treatment responses. Infected patients in the Boryoung cluster had significantly more generalized weakness, eschars, skin rashes, conjunctival injection, high albumin levels, and greater ESR and fibrinogen levels compared to the Karp cluster. The treatment response to current antibiotics was significantly slower in the Karp cluster as compared to the Boryoung cluster.Conclusion
The frequency of occurrence of eschars and rashes may depend on the genotype of O. tsutsugamushi. 相似文献102.
Exposure to artificial light at night (ALAN) has been reported to be associated with various pathological changes including sleep deprivation, circadian rhythm disruption, and melatonin suppression with increase in various cancers such as breast or prostate cancers. In this study, we sought to elucidate the association between ALAN and prostate cancer in 27 districts within Gwangju City and urban and rural areas from South Jeolla Province in South Korea. We analyzed the correlation between ALAN and the incidence of a range of cancers by Poisson regression analysis, after adjustment for confounding risk factors, such as smoking, drinking, obesity, stress, air pollution (particulate matter <10 μm in diameter), urbanization (proportion of urbanized area), and the cancer screening rate. Interestingly, the incidence of prostate cancer was significantly associated with ALAN (risk ratio = 1.02, p = 0.0369) and urbanization (risk ratio = 1.06, p = 0.0055). In particular, comparing the prostate cancer incidence at 25% and 75% level of ALAN, the risk ratio was 1.726 (12.6 over 7.3, respectively). No significant association was observed between ALAN and other cancers, including stomach, esophageal, liver, pancreatic, laryngeal, lung and tracheal, bladder, and brain and central nervous system cancers, as well as lymphoma and multiple myeloma. In conclusion, this study shows that a high incidence of prostate cancer may be independently associated with light pollution and urbanization, which represent significant factors in the rapid process of industrialization of South Korea. 相似文献
103.
Shenqiang Rao Shuangmei Liu Lifang Zou Tianyu Jia Shanhong Zhao Bing Wu Zhihua Yi Shouyu Wang Yun Xue Yun Gao Changshui Xu Guilin Li Hong Xu Chunping Zhang Shangdong Liang 《Purinergic signalling》2017,13(2):227-235
Type 2 diabetes mellitus (T2DM) accounts for more than 90% of all cases of diabetes mellitus (DM). Diabetic neuropathic pain (DNP) is a common complication of T2DM. Sinomenine is a natural bioactive component extracted from the Sinomenium acutum and has anti-inflammatory effects. The aim of our study was to investigate the effects of sinomenine on DNP mediated by the P2X3 receptor in dorsal root ganglia (DRG). The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) in T2DM rats were lower than those of control rats. MWT and TWL in T2DM rats treated with sinomenine were higher compared with those in T2DM rats. The expression levels of the P2X3 protein and mRNA in T2DM rat DRG were higher compared with those of the control, while those in T2DM rats treated with sinomenine were significantly lower compared with those of the T2DM rats. Sinomenine significantly inhibited P2X3 agonist ATP-activated currents in HEK293 cells transfected with the P2X3 receptor. Sinomenine decreased the phosphorylation and activation of P38MAPK in T2DM DRG. Therefore, sinomenine treatment may suppress the up-regulated expression and activation of the P2X3 receptor and relieve the hyperalgesia potentiated by the activation of P38MAPK in T2DM rats. 相似文献
104.
【目的】塑料废物处理是世界环境难题,近期有研究报道黄粉虫可啮食聚苯乙烯泡沫塑料,肠道细菌可能在黄粉虫生物降解塑料的过程中起重要作用。本文以啮食聚苯乙烯泡沫塑料的黄粉虫幼虫(Tenebrio molitor)为材料,探究其肠道细菌的多样性和细菌群落组成。【方法】分别以聚苯乙烯泡沫塑料(聚苯乙烯组)和纸片(对照组)为唯一食物来源喂养黄粉虫幼虫,在90 d后采集粪便样品,对16S r RNA基因V3-V4区进行PCR扩增和高通量测序,并以PICRUSt进行肠道菌群的功能预测。【结果】饲喂期间,两组黄粉虫均正常存活,部分幼虫完成变态发育。泡沫塑料有明显的减重。样本测序共得到144 258条有效序列,179个OTU,共涉及10个门111个属。其中,聚苯乙烯组黄粉虫的肠道细菌在属水平高丰度的是Alcaligenes(35.9%)、Brevundimonas(12.3%)、Myroides(10.3%)。基于16S r RNA基因序列的功能预测表明,在聚苯乙烯组中,芳香类化合物的降解基因被明显富集。【结论】高通量测序揭示了啮食聚苯乙烯泡沫塑料的黄粉虫肠道菌群的多样性,这对从黄粉虫肠道中分离高效降解聚苯乙烯的细菌具有指导意义。 相似文献
105.
Wei Huang Yong-Mei Xia Hui Gao Yin-Jun Fang Yi Wang Yun Fang 《Journal of Molecular Catalysis .B, Enzymatic》2005,35(4-6):113-116
The enzymatic esterification between n-alcohol homologs and n-caprylic acid catalyzed by lipozyme RM IM (LRI) in microwave field was investigated. Some interesting findings were obtained. The optimum reaction temperature slightly shifted from that in enzymatic esterification by conventional heating. n-Alcohol homologs used in this experiment showed substrate specificity in terms of the odd and even carbon numbers. THF expressed abnormal solvent effect. Whereas in the contrastive enzymatic esterification by conventional heating, the above mentioned substrate specificity and solvent effect were not observed. All the above phenomena could be explained by both thermal and non-thermal effect of microwave on enzyme and substrates. Further investigation revealed that microwave irradiation reduced the apparent activation energy of the enzymatic reaction according to Arrhenius equation, which is considered as one of the causes increasing initial reaction rate. 相似文献
106.
青鱼生长激素的重组表达及其多克隆抗体的制备 总被引:2,自引:0,他引:2
以含有的青鱼生长激素编码区cDNA的重组质粒pbcGHc为模板,高保真PCR扩增青鱼生长激素(GH)成熟肽cDNA序列,定向插入原核表达载体pET-28a,构建青鱼GH原核表达质粒pET-bcGH。将pET-bcGH转化大肠杆菌BL21(DE3),IPTG诱导青鱼GH基因在大肠杆菌中的融合表达,SDS-PAGE凝胶电泳结果显示一条23 kDa的诱导表达重组青鱼GH带。以草鱼GH多克隆抗体为一抗,Western Blot证明,该重组青鱼GH具有免疫学活性。将经过亲和层析、透析纯化后的重组青鱼GH作为抗原,采用改进的方法对家兔进行皮下免疫注射,获得青鱼GH多克隆抗血清。以该多抗为一抗,Western Blot 可以检测出4 ng的抗原量;并且在青鱼垂体组织抽提液中和血清中检测到一种能与该抗血清作用的大小为21 kDa的蛋白质。这些结果表明本研究得到的青鱼GH多克隆抗血清具有较好的免疫特性。 相似文献
107.
108.
Alternative splicing of mRNA allows many gene products with different functions to be produced from a single coding sequence. Exon skipping is the most commonly known alternative splicing mechanism. A comprehensive database of alternative splicing by exon skipping is made available for the human genome data. 1,229 human genes are identified to exhibit alternative splicing by exon skipping. Availability: http://sege.ntu.edu.sg/wester/ashes/. 相似文献
109.
DNA topoisomerase (topo) IIalpha, an essential enzyme for cell proliferation, is targeted to a proteasome-dependent degradation pathway when human tumor cells are glucose-starved. Here we show that the topo IIalpha destabilization depends on the newly identified domain, GRDD (glucose-regulated destruction domain), which was mapped to the N-terminal 70-170 amino acid sequence. Indeed, the deletion of GRDD conferred a stable feature on topo IIalpha, whereas the fusion of GRDD rendered green fluorescent protein unstable under glucose starvation conditions. Nuclear localization was a prerequisite for GRDD function, because the inhibition of nuclear translocation resulted in the suppression of GRDD-mediated topo IIalpha degradation. Further, GRDD was identified as an interactive domain for Jab1/CSN5, which promoted the degradation of topo IIalpha in a manner dependent on the MPN (Mpr1p/Prd1p N terminus) domain. Depleting Jab1/CSN5 by antisense oligonucleotide and treating cells with the CSN-associated kinase inhibitor, curcumin, inhibited topo IIalpha degradation induced by glucose starvation. These findings demonstrate that GRDD can act as a stress-activated degron for regulating topo IIalpha stability, possibly through interaction with the MPN domain of Jab1/CSN5. 相似文献
110.
Characterization of a fungal strain capable of degrading chlorpyrifos and
its use in detoxification of the insecticide on vegetables 总被引:2,自引:0,他引:2
A fungal strain capable of utilizing chlorpyrifos as sole carbon and energy sources was isolated from soil by enrichment cultivation approach. The half-lives of degradation (DT50) for chlorpyrifos at concentrations of 1, 10, and 100 mg l−1 by the fungal strain DSP in mineral salt medium were measured to be 2.03, 2.93, and 3.49 days, respectively. Two cell-free extracts [E (1:10) and E (1:20)] from the fungal strain DSP in bran–glucose medium were prepared and used to enhance chlorpyrifos degradation on vegetables. Compared with the controls, the DT50 of chlorpyrifos were reduced by 70.3%, 65.6%, 80.6%, 80.6%, and 86.1%, and by 53.8%, 43.2%, 66.0%, 54.3%, and 67.7% on E (1:20) and E (1:10) treated pakchoi, water spinach, Malabar spinach, haricot beans, and pepper, respectively. The 7-day residual values (R
7) of chlorpyrifos on E (1:10) treated vegetables were all lower than the corresponding maximum residue levels of European Union (EU MRLs), except that the R
7 value on haricot beans was slightly higher than the corresponding EU MRLs. The results indicate that cell-free extracts could rapidly degrade chlorpyrifos residues on vegetables. 相似文献