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1.
The desulfurization activity of the resting cells of Gordona sp. CYKS1 was strongly depended on harvest time and the highest value when the cells had been harvested in the early growth phase (0.12 mg sulfur g–1 cell–1 h–1). For the model oil, hexadecane containing dibenzothiophene, the specific desulfurization rate decreased as the reaction proceeded. Both the specific and the volumetric desulfurization rates were not significantly affected by the aqueous-to-oil phase ratio. The diesel oils, light gas oil and a middle distillate unit feed were desulfurized at higher rates (ca. 0.34 mg sulfur g–1 cell–1 h–1) than the model oil (0.12 mg sulfur g–1 cell–1 h–1). 相似文献
2.
The purpose of this review is to provide an overview of the effects of adenovirus and influenza virus infections on obesity in various experimental models. We reviewed studies that were conducted within the past 10 years and were related to virus infection and obesity prevalence. Here, we discuss a different causal relationship between adenovirus and influenza infections with obesity. Adenovirus infection can cause obesity, whereas obesity can be a risk factor for increasing influenza virus infection and increases the risk of morbidity and mortality. The prevalence of obesity due to adenovirus infections may be due to an increase in glucose uptake and reduction in lipolysis caused by an increase in corticosterone secretion. Adenovirus infections may lead to increases in appetite by decreasing norepinephrine and leptin levels and also cause immune dysfunction. The relationship between obesity and influenza virus infection could be summarized by the following features: decreases in memory T-cell functionality and interferon (IFN)-α, IFN-β, and IFN-γ mRNA expression, increases in viral titer and infiltration, and impaired dendritic cell function in obese individuals. Moreover, leptin resistance may play an important role in increasing influenza virus infections in obese individuals. In conclusion, prevention of adenovirus infections could be a good approach for reducing obesity prevalence, and prevention of obesity could reduce influenza virus infections from the point of view of viral infections and obesity. 相似文献
3.
4.
Preventing Staphylococcus aureus sepsis through the inhibition of its agglutination in blood 总被引:1,自引:0,他引:1
McAdow M Kim HK Dedent AC Hendrickx AP Schneewind O Missiakas DM 《PLoS pathogens》2011,7(10):e1002307
Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci--coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA)--were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans. 相似文献
5.
Keun Soo Ahn Sung-Tae Hong Yu Na Kang Jung Hyeok Kwon Mi Jeong Kim Tae Jun Park Yong Hoon Kim Tae Jin Lim Koo Jeong Kang 《The Korean journal of parasitology》2012,50(4):357-360
A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''. 相似文献
6.
HIV-1 integrase (IN) is an essential enzyme for the viral replication and an interesting target for the design of new pharmaceuticals for multidrug therapy of AIDS. Single and multiple mutations of IN at residues T66, S153, or M154 confer degrees of resistance to several inhibitors that prevent the enzyme from performing its normal strand transfer activity. Four different conformations of IN were chosen from a prior molecular dynamics (MD) simulation on the modeled IN T66I/M154I catalytic core domain as starting points for additional MD studies. The aim of this article is to understand the dynamic features that may play roles in the catalytic activity of the double mutant enzyme in the absence of any inhibitor. Moreover, we want to verify the influence of using different starting points on the MD trajectories and associated dynamical properties. By comparison of the trajectories obtained from these MD simulations we have demonstrated that the starting point does not affect the conformational space explored by this protein and that the time of the simulation is long enough to achieve convergence for this system. 相似文献
7.
Bacillus subtilis SC-8 is a Gram-positive bacterium displaying narrow antagonistic activity for the Bacillus cereus group. B. subtilis SC-8 was isolated from Korean traditional fermented-soybean food. Here we report the draft genome sequence of B. subtilis SC-8, including biosynthetic genes for antibiotics that may have beneficial effects for control of food-borne pathogens. 相似文献
8.
Yong-Hun Park Sang Keun Ha Inwook Choi Kyu Sik Kim Jeryang Park Nakwon Choi Bumsang Kim Jong Hwan Sung 《Biotechnology and Bioprocess Engineering》2016,21(1):110-118
Transdermal drug delivery system (TDDS) may provide a more reliable method of drug delivery than oral delivery by avoiding gut absorption and first-pass metabolism, but needs a method for efficiently crossing the epidermal barrier. To enhance the delivery through the skin, we have developed a biocompatible, dissolvable microneedle array made from carboxymethyl cellulose (CMC). Using laser ablation for creating the mold greatly improved the efficiency and reduced the cost of microneedle fabrication. Mixing CMC with amylopectin (AP) enhanced the mechanical and tunable dissolution properties of the microneedle for controlled release of model compounds. Using the CMC microneedle array, we observed significant enhancement in the skin permeability of a fluorescent model compound, and also increase in the anti-oxidant activity of ascorbic acid after crossing the skin. Our dissolvable microneedle array provides a new and biocompatible method for delivery of drugs and cosmetic compounds through the skin. 相似文献
9.
Leem JY Park DS Suh EY Hur JH Oh HW Park HY 《Archives of insect biochemistry and physiology》2007,66(4):204-213
A new antimicrobial peptide, cryptonin, was isolated and characterized from the adult Korean blackish cicada, Cryptotympana dubia. It consists of 24 amino acid residues and has a molecular weight of 2,704 Da on mass spectroscopy. The predicted alpha-helical structure analysis and increased helix percent in 40% trifloroethanol of cryptonin suggests that it belongs to the typical linear alpha-helix forming peptide. Binding of the biotin-labeled cryptonin at the surface of E. coli cells and increased influx of propidium iodide in E. coli after cryptonin treatment indicates that it kills microbial cells by binding bacterial cell surfaces and disrupting the cell permeability. Cryptonin showed strong antibacterial (MIC 1.56-25 microg/ml) and antifungal (MIC 3.12-50 microg/ml) activities against tested bacteria and fungi including two antibiotic-resistant bacterial strains; methicilin-resistant S. aureus and vancomycin-resistant Enterococci (MIC 25 microg/ml, each). 相似文献
10.
The Arabidopsis RING E3 ubiquitin ligase AtAIRP2 plays combinatory roles with AtAIRP1 in abscisic acid-mediated drought stress responses 总被引:1,自引:0,他引:1
The ubiquitin (Ub)-26S proteasome pathway is implicated in various cellular processes in higher plants. AtAIRP1, a C3H2C3-type RING (for Really Interesting New Gene) E3 Ub ligase, is a positive regulator in the Arabidopsis (Arabidopsis thaliana) abscisic acid (ABA)-dependent drought response. Here, the AtAIRP2 (for Arabidopsis ABA-insensitive RING protein 2) gene was identified and characterized. AtAIRP2 encodes a cytosolic C3HC4-type RING E3 Ub ligase whose expression was markedly induced by ABA and dehydration stress. Thus, AtAIRP2 belongs to a different RING subclass than AtAIRP1 with a limited sequence identity. AtAIRP2-overexpressing transgenic (35S:AtAIRP2-sGFP) and atairp2 loss-of-function mutant plants exhibited hypersensitive and hyposensitive phenotypes, respectively, to ABA in terms of seed germination, root growth, and stomatal movement. 35S:AtAIRP2-sGFP plants were highly tolerant to severe drought stress, and atairp2 alleles were more susceptible to water stress than were wild-type plants. Higher levels of drought-induced hydrogen peroxide production were detected in 35S:AtAIRP2-sGFP as compared with atairp2 plants. ABA-inducible drought-related genes were up-regulated in 35S:AtAIRP2-sGFP and down-regulated in atairp2 progeny. The positive effects of AtAIRP2 on ABA-induced stress genes were dependent on SNF1-related protein kinases, key components of the ABA signaling pathway. Therefore, AtAIRP2 is involved in positive regulation of ABA-dependent drought stress responses. To address the functional relationship between AtAIRP1 and AtAIRP2, FLAG-AtAIRP1 and AtAIRP2-sGFP genes were ectopically expressed in atairp2-2 and atairp1 plants, respectively. Constitutive expression of FLAG-AtAIRP1 and AtAIRP2-sGFP in atairp2-2 and atairp1 plants, respectively, reciprocally rescued the loss-of-function ABA-insensitive phenotypes during germination. Additionally, atairp1/35S:AtAIRP2-sGFP and atairp2-2/35S:FLAG-AtAIRP1 complementation lines were more tolerant to dehydration stress relative to atairp1 and atairp2-2 single knockout plants. Overall, these results suggest that AtAIRP2 plays combinatory roles with AtAIRP1 in Arabidopsis ABA-mediated drought stress responses. 相似文献