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991.
This investigation aimed to evaluate the differential expression of HoxB7 and notch genes in different developmental stages of Echinococcus granulosus sensu stricto. The expression of HoxB7 gene was observed at all developmental stages. Nevertheless, significant fold differences in the expression level was documented in the juvenile worm with 3 or more proglottids, the germinal layer from infected sheep, and the adult worm from an experimentally infected dog. The notch gene was expressed at all developmental stages of E. granulosus; however, the fold difference was significantly increased at the microcysts in monophasic culture medium and the germinal layer of infected sheep in comparison with other stages. The findings demonstrated that the 2 aforementioned genes evaluated in the present study were differentially expressed at different developmental stages of the parasite and may contribute to some important biological processes of E. granulosus.  相似文献   
992.
Introduction: Trauma is one of the causes of peripheral nerve injuries. Free radicals increase after tissue damage. Free radicals are usually scavenged and detoxi?ed by antioxidants. In this study, we assessed the antioxidative role of the NGAL molecule in sciatic nerve repair in rats. Materials and methods: The sciatic nerves of 40 rats were crushed and the total mRNA of samples from day 1 and 3 and week 1, 3, 5 post injury was extracted. The expression of the NGAL gene was confirmed by RT-PCR. For immunohistochemistry analysis, the samples were ?xed in paraformaldehyde and cut in 20 micrometer slices by cryostat. Results: The expression of NGAL signi?cantly upregulated in day 1, 3 and week 1 following the crushing of sciatic nerves in comparison with the intact nerves. Immunohistochemistry results also confirmed the protein expression of this gene. Discussion: The NGAL molecule showed upregulation in the degeneration process after nerve injury, so it may play an important role in nerve repair.  相似文献   
993.
Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications.  相似文献   
994.

Introduction

To examine the associations between smoking and cardiovascular disease (CVD) / coronary heart disease (CHD) and all-cause mortality events in men with and without type 2 diabetes (T2D) in a Middle Eastern cohort during a median follow-up of 12 years.

Methods

The study population included 2230 subjects aged ≥ 40 years, free from CVD, comprised of 367 participants with diabetes (21.2% current smokers) and 1863 without (27.3% current smokers). Multivariate Hazard ratios (HR) and 95% confidence intervals (CI) were calculated for smoking (considering different definitions) for those with and without diabetes. Potential confounding factors including age, body mass index, estimated Glomerular Filtration Rate, hypertension, hypercholesterolemia and educational level were entered in the multivariate analysis.

Results

In men with diabetes, the HR (95% CI) of comparing current and non-smokers was 1.25 (0.74–2.12) for incident CHD, 1.52 (0.96–2.40) for CVD and 2.10 (1.27–3.47) for mortality events; the corresponding values for men without diabetes were 1.65 (1.24–2.20), 1.70 (1.30–2.22) and 1.72 (1.14–2.58), respectively (all P values for interactions > 0.46). After pooling past smokers with current smokers, among diabetic individuals there was no significant risk for CVD [1.29 (0.89–1.86)] or mortality events [1.25 (0.81–1.92)]; however, among non-diabetic individuals the HRs of current/past smokers reached significant levels for CVD [1.53 (1.23–1.91)] but not for mortality outcomes (all P values for interactions > 0.51).

Conclusions

The strength of the associations between smoking habits and incident CVD/CHD and mortality events from all causes did not differ significantly among diabetic and non-diabetic participants. Therefore, a comprehensive community-based smoking prevention program is important, given the increasing trend of smoking among the Iranian population regardless of diabetes status.  相似文献   
995.
Mesophilic and thermophilic anaerobic digesters (MD and TD, respectively) utilizing Gracilaria and marine sediment as the substrate and inoculum, respectively, were compared by analyzing their performances and microbial community changes. During three successive transfers, the average cumulative methane yields in the MD and TD were 222.6 ± 17.3 mL CH4/g volatile solids (VS) and 246.1 ± 11 mL CH4/g VS, respectively. The higher hydrolysis rate and acidogenesis in the TD resulted in a several fold greater accumulation of volatile fatty acids (acetate, propionate, and butyrate) followed by a larger pH drop with a prolonged recovery than in the MD. However, the operational stability between both digesters remained comparable. Pyrosequencing analyses revealed that the MD had more complex microbial diversity indices and microbial community changes than the TD. Interestingly, Methanomassiliicoccales, the seventh methanogen order was the predominant archaeal order in the MD along with bacterial orders of Clostridiales, Bacteriodales, and Synergistales. Meanwhile, Coprothermobacter and Methanobacteriales dominated the bacterial and archaeal community in the TD, respectively. Although the methane yield is comparable, both MD and TD show a different profile of pH, VFA and the microbial communities.  相似文献   
996.
997.
A bench-scale integrated process based on submerged aerobic powdered activated carbon-membrane bioreactor (PAC-MBR) has been utilized and established for the treatment of landfill leachate. The results showed that the submerged PAC-MBR system effectively removed biodegradable trace organic compounds by the average removal rate about 71 % at optimum food to microorganism (F/M) ratio of 0.4 gCOD/g day under a HRT of 24 h. Adding nanofiltration (NF) process increased the treatment efficiency up to 99 %. Further, adding powdered activated carbon to activated sludge (AS) resulted in a higher adsorption capacity in comparison with AS. Adsorption isotherms were investigated and fitted by the Langmuir and Freundlich isotherm models in which the Langmuir model performed better. The specific oxygen uptake rate (SOUR) showed that adding PAC reduces the effects of COD on microorganism activities. NH3–N, TKN and Heavy metals removal efficiency amounted to 97 ± 2, 96 ± 2, and 99 ± 2 %, respectively.  相似文献   
998.
Phage display is a powerful methodology for the identification of peptide ligands binding to any desired target. However, the selection of target-unrelated peptides (TUPs) appears as a huge problem in the screening of phage display libraries through biopanning. The phage-displayed peptide TLHPAAD has been isolated both in our laboratory and by another reserach group on completely different screening targets prompting us to hypothesize that it may be a potential TUP. In the current study, we analyzed the binding characteristics and propagation rate of phage clone displaying TLHPAAD peptide (SW-TUP clone). The results of ELISA experiment and phage recovery assay provided strong support for the notion that SW-TUP phage binds to polystyrene with a significantly higher affinity than control phage clones. Furthermore, this polystyrene binding was demonstrated to occur in a concentration- and pH-dependent mode. Characterization of the propagation profile of phage clones within a specified time course revealed no statistically significant difference between the amplification rate of SW-TUP and control phages. Our findings lead us to the conclusion that SW-TUP phage clone with the displayed peptide TLHPAAD is not a true target binder and its selection in biopanning experiments results from its bidning affinity to the polystyrene surface of the solid phase.  相似文献   
999.
There are a few studies with conflicting results on the effects of opioids on the functioning of immune system. This study was performed to investigate the in vitro production of interferon-gamma and interleukin-10 after antigenic stimulation of cells using whole blood from opioid addicts. Blood samples were taken from 20 chronically opioid-addicted persons, who voluntarily enrolled for detoxification (10 opium and 10 heroin addicts). Blood samples were also taken from 10 healthy individuals with no history of drug abuse as the control. Cell culture was performed in a whole blood culture assay. Diluted blood samples were stimulated with phytohemagglutinin or with lipopolysaccharide and the supernatants were collected to measure cytokine production. The results demonstrated a significant decrease in interferon-gamma production and an increase in interleukin-10 secretion in heroin addicts, relative to the control group (35.9+/-26.3 versus 110.2+/-60.3 pg/mL, p<0.01 and 71.8+/-28.4 versus 17.1+/-13.5 pg/mL, p<0.01, respectively), however the changes in these values in opium addicts were not significant compared to healthy individuals. The results could suggest that opioid addiction leads to a shift in the Th1/Th2 cytokine balance of peripheral CD4+ cells towards the Th2 response, and opioid addicts demonstrate reduced mitogenic responsiveness of lymphocytes relative to healthy individuals.  相似文献   
1000.
The herpes simplex viruses are important causes of disease worldwide. Herpes simplex virus type 1 (HSV-1) is the primary cause of oral-facial and pharyngeal infections and may cause herpetic whitlow, eye infections as well as severe and sometimes dangerous infections of the eyes and brain. HSV-1 also accounts for 10-15% of all genital herpetic infections. Therefore, laboratory diagnosis of this virus and development of diagnostic serological techniques for HSV-1 is of particular importance. In the present study, pTrc His2A-gG1 plasmid, containing the full-length glycoprotein G (gG) protein, was produced in a prokaryotic system for the first time. Upon confirmation of a 37-kDa gG-1 protein production in a prokaryotic system based on western blotting and monoclonal antibodies, the protein was produced at a large scale and purified by ion-exchange chromatography using DEAE-sepharose. An HSV-1 type-specific diagnostic kit was designed and developed and the specificity and sensitivity of this kit were demonstrated to be 89.5% and 100%, respectively, as compared with a commercially available kit. A significant correlation was shown between the developed kit and the commercial kit.  相似文献   
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