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101.
Guohong Liu Bo Liu Naiquan Lin Weiqi Tang Jianyang Tang Yingzhi Lin 《Journal of bacteriology》2012,194(23):6633
Bacillus sp. strain FJAT-13831 was isolated from the no. 1 pit soil of Emperor Qin''s Terracotta Warriors in Xi''an City, People''s Republic of China. The isolate showed a close relationship to the Bacillus cereus group. The draft genome sequence of Bacillus sp. FJAT-13831 was 4,425,198 bp in size and consisted of 5,567 genes (protein-coding sequences [CDS]) with an average length of 782 bp and a G+C value of 36.36%. 相似文献
102.
S S Bo?ko V P Zherdev A A Dvorianinov I Janku E Buchar 《Biulleten' eksperimental'no? biologii i meditsiny》1990,110(11):501-503
Pharmacokinetics of novel immunostimulating drug kamantane was studied by using gas-liquid chromatography in experiments on rats. It was found that kemantane biotransformed rapidly after oral administration with the forming of active metabolite. Kemantane and its metabolites are distributed rapidly from the blood to organs. The drug is eliminated from the organism of rats as metabolite. 相似文献
103.
Bo Lin Dipika Gupta Christopher D. Heinen 《The Journal of biological chemistry》2014,289(35):24314-24324
Human pluripotent stem cells (PSCs) are presumed to have robust DNA repair pathways to ensure genome stability. PSCs likely need to protect against mutations that would otherwise be propagated throughout all tissues of the developing embryo. How these cells respond to genotoxic stress has only recently begun to be investigated. Although PSCs appear to respond to certain forms of damage more efficiently than somatic cells, some DNA damage response pathways such as the replication stress response may be lacking. Not all DNA repair pathways, including the DNA mismatch repair (MMR) pathway, have been well characterized in PSCs to date. MMR maintains genomic stability by repairing DNA polymerase errors. MMR is also involved in the induction of cell cycle arrest and apoptosis in response to certain exogenous DNA-damaging agents. Here, we examined MMR function in PSCs. We have demonstrated that PSCs contain a robust MMR pathway and are highly sensitive to DNA alkylation damage in an MMR-dependent manner. Interestingly, the nature of this alkylation response differs from that previously reported in somatic cell types. In somatic cells, a permanent G2/M cell cycle arrest is induced in the second cell cycle after DNA damage. The PSCs, however, directly undergo apoptosis in the first cell cycle. This response reveals that PSCs rely on apoptotic cell death as an important defense to avoid mutation accumulation. Our results also suggest an alternative molecular mechanism by which the MMR pathway can induce a response to DNA damage that may have implications for tumorigenesis. 相似文献
104.
Bo Ram Kim Ji-Young Park Hyung Jae Jeong Hyung-Jun Kwon Su-Jin Park In-Chul Lee 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):1256-1265
Sialidases are key virulence factors that remove sialic acid from the host cell surface glycan, unmasking receptors that facilitate bacterial adherence and colonisation. In this study, we developed potential agents for treating bacterial infections caused by Streptococcus pneumoniae Nan A that inhibit bacterial sialidase using Turmeric and curcumin analogues. Design, synthesis, and structure analysis relationship (SAR) studies have been also described. Evaluation of the synthesised derivatives demonstrated that compound 5e was the most potent inhibitor of S. pneumoniae sialidase (IC50?=?0.2?±?0.1?µM). This compound exhibited a 3.0-fold improvement in inhibitory activity over that of curcumin and displayed competitive inhibition. These results warrant further studies confirming the antipneumococcal activity 5e and indicated that curcumin derivatives could be potentially used to treat sepsis by bacterial infections. 相似文献
105.
Advanced hepatic fibrosis therapy using drug-delivering nanoparticles is a relatively unexplored area. Angiotensin type 1 (AT1) receptor blockers such as losartan can be delivered to hepatic stellate cells (HSC), blocking their activation and thereby reducing fibrosis progression in the liver. In our study, we analyzed the possibility of utilizing drug-loaded vehicles such as hyaluronic acid (HA) micelles carrying losartan to attenuate HSC activation. Losartan, which exhibits inherent lipophilicity, was loaded into the hydrophobic core of HA micelles with a 19.5% drug loading efficiency. An advanced liver fibrosis model was developed using C3H/HeN mice subjected to 20 weeks of prolonged TAA/ethanol weight-adapted treatment. The cytocompatibility and cell uptake profile of losartan-HA micelles were studied in murine fibroblast cells (NIH3T3), human hepatic stellate cells (hHSC) and FL83B cells (hepatocyte cell line). The ability of these nanoparticles to attenuate HSC activation was studied in activated HSC cells based on alpha smooth muscle actin (α-sma) expression. Mice treated with oral losartan or losartan-HA micelles were analyzed for serum enzyme levels (ALT/AST, CK and LDH) and collagen deposition (hydroxyproline levels) in the liver. The accumulation of HA micelles was observed in fibrotic livers, which suggests increased delivery of losartan compared to normal livers and specific uptake by HSC. Active reduction of α-sma was observed in hHSC and the liver sections of losartan-HA micelle-treated mice. The serum enzyme levels and collagen deposition of losartan-HA micelle-treated mice was reduced significantly compared to the oral losartan group. Losartan-HA micelles demonstrated significant attenuation of hepatic fibrosis via an HSC-targeting mechanism in our in vitro and in vivo studies. These nanoparticles can be considered as an alternative therapy for liver fibrosis. 相似文献
106.
The effect of overexpression of the heat shock chaperone genes dnaK and groESL on heterologous protein production in Escherichia coli was examined, using a set of related human procollagenase proteins. A diverse range of effects on protein solubility, secretion, and accumulation was observed, and these effects were highly dependent on the particular chaperone/procollagenase pairing involved. Both chaperones caused a large increase in the apparent solubility of a fusion of the LamB signal peptide to procollagenase. GroESL had no effect on the accumulation of mature (secreted) procollagenase, while DnaK suppressed secretion considerably. In the absence of a signal peptide, overexpression of either chaperone resulted in a dramatic increase in both solubility and accumulation of procollagenase. The 10-fold increase in accumulation was associated with an increase in in vivo protein half-life. 相似文献
107.
108.
109.
Lee D. Major Thomas S. Partridge Joy Gardner Stephen J. Kent Robert de Rose Andreas Suhrbier Wayne A. Schroder 《PloS one》2013,8(2)
SerpinB2, also known as plasminogen activator inhibitor type 2, is a major product of activated monocytes/macrophages and is often strongly induced during infection and inflammation; however, its physiological function remains somewhat elusive. Herein we show that SerpinB2 is induced in peripheral blood mononuclear cells following infection of pigtail macaques with CCR5-utilizing (macrophage-tropic) SIVmac239, but not the rapidly pathogenic CXCR4-utilizing (T cell-tropic) SHIVmn229. To investigate the role of SerpinB2 in lentiviral infections, SerpinB2−/− mice were infected with EcoHIV, a chimeric HIV in which HIV gp120 has been replaced with gp80 from ecotropic murine leukemia virus. EcoHIV infected SerpinB2−/− mice produced significantly lower anti-gag IgG1 antibody titres than infected SerpinB2+/+ mice, and showed slightly delayed clearance of EcoHIV. Analyses of published microarray studies showed significantly higher levels of SerpinB2 mRNA in monocytes from HIV-1 infected patients when compared with uninfected controls, as well as a significant negative correlation between SerpinB2 and T-bet mRNA levels in peripheral blood mononuclear cells. These data illustrate that SerpinB2 can be induced by lentiviral infection in vivo and support the emerging notion that a physiological role of SerpinB2 is modulation of Th1/Th2 responses. 相似文献
110.
Modelling species distributions has been widely used to understand present and future potential distributions of species, and can provide adaptation and mitigation information as references for conservation and management under climate change. However, various methods of data splitting to develop and validate functions of the models do not get enough attention, which may mislead the interpretation of predicted results. We used the Taiwanese endemic birds to test the influences of temporal independence of datasets on model performance and prediction. Training and testing data were considered to be independent if they were collected during different survey periods (1993–2004 and 2009–2010). The results indicated no significant differences of six model performance measures (AUC, kappa, TSS, accuracy, sensitivity, and specificity) among the combinations of training and testing datasets. Both species- and grid cell-based assessments differed significantly between predictions by the annual and pooled training data. We also found an average of 85.8% similarity for species presences and absences in different survey periods. The remaining dissimilarity was mostly caused by species observed in the late survey period but not in the early one. The method of data splitting, yielding training and testing data, is critical for resulting model species distributions. Even if similar model performance exists, different methods can lead to different species distributional maps. More attention needs to be given to this issue, especially when amplifying these models to project species distributions in a changing world. 相似文献