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81.
82.
Backgrounds: Most of the hepatitis C virus (HCV) infections elicit poor immune responses and 75% to 85% of cases become chronic; therefore, the development of an effective vaccine against HCV is of paramount importance. In this study, we aimed to evaluate co-administration of HCV non-Structural Protein 2 and IL-12 DNA vaccines in C57BL/6 mice. Methods: A plasmid encoding full-length HCV NS2 protein (non-structural protein 2) was generated and used to vaccinate mice. Negative control (an empty expression vector) was also employed to evaluate the background response. To investigate immune responses against vaccine, C57BL/6 mice received three doses of the vaccine with a two-week interval. Cellular immunity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay for lymphocyte proliferation, lactate dehydrogenase release for cytotoxic T lymphocyte (CTL) activity and cytokine assay. Results: The findings demonstrated that immunization of mice with plasmid expressing HCV NS2 induced CTL response, interferon gamma production, and lymphocyte proliferation compared to negative control. The results also demonstrated that co-administration of IL-12 with the HCV NS2 plasmid induced significantly better immune response in C57BL/6 mice. Conclusion: DNA vaccine encoding HCV NS2 is an effective candidate that can trigger CTL-based immune response against HCV. In addition, the results suggested that combining the DNA vaccine approach with immune stimulatory cytokines may significantly enhance antigen-specific immune responses. Key Words: Hepatitis C virus (HCV), NS2 protein, DNA vaccine, IL-12  相似文献   
83.
Background: It is well known that the development of brain oxidative stress is one of the most serious complications of arterial hypertension that evokes brain tissue damage. The aim of this study was to examine the effects of atorvastatin treatment (20 mg/kg/day), as an antioxidant, to prevent the brain tissue oxidative stress in the hypertensive (HTN) rats. Methods: Experiments were performed in four groups of rats (n = 5 each group): sham, sham-treated, HTN and HTN treated. Rats were made HTN by aortic constriction above the renal arteries. After 30 days, rats were slaughtered under deep anesthesia to remove brain hemispheres. After tissue homogenization, enzyme activities of superoxide dismutase (SOD) and catalase (CAT), as well as glutathione (GSH) content and malondialdehyde (MDA) level were determined by biochemical methods. Results: In HTN rats, arterial blood pressure was increased about 40% and brain enzyme activities of SOD and CAT were significantly decreased compared with sham group. Induction of hypertension significantly decreased GSH content and increased MDA level of brain tissue. Treatment with atorvastatin enhanced the activity of SOD and prevented from GSH decrement during hypertension. Conclusion: Based on the findings of this study, treatment with atorvastatin might have saved the brain tissue of HTN rats from hypertension-induced oxidative stress. Key Words: Atorvastatin, Aortic coarctation, Oxidative stress, Hypertension  相似文献   
84.
Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease with many genetic factors predisposing to disease susceptibility. The aim of the present study was to investigate the impact of CD226 rs727088 and rs763361 polymorphisms and susceptibility to RA in a sample of the Iranian population. Methods: This case-control study was carried out on 100 patients with RA and 104 healthy subjects. The polymorphisms were determined using tetra amplification refractory mutation system-polymerase chain reaction assay. Results: The rs763361 (Gly307Ser) polymorphism increased the risk of RA in codominant, dominant and recessive-tested inheritance models (odds ratio [OR] = 3.18, 95% confidence intervals [95% CI] = 1.44-7.02, P = 0.004, CC vs. TT, and OR = 1.98, 95% CI = 1.10-3.57, P = 0.023, CC vs. CT-TT, and OR = 2.61, 95% CI = 1.26-5.37, P = 0.010, CC + CT vs. TT, respectively). In addition, the rs763361 T allele increased the risk of RA (OR = 2.06, 95% CI = 1.38-3.08, P<0.001). However, no significant difference was observed among the groups regarding CD226 rs727088 polymorphism (χ2 = 3.20, P = 0.202). Conclusions: Our finding showed that CD226 rs763361, but not rs727088, gene polymorphism increased the risk of RA in a sample of the Iranian population.Key Words: Rheumatoid arthritis (RA), CD226, Polymorphism  相似文献   
85.
A 1-week old, two-humped female camel (Camelus bactrianus) calf with continual whining, epiphora, anorexia, muscle twitching, and lateral recumbency was referred to a veterinary hospital. Although she died shortly after preliminary clinical examination, but necropsy was performed and tissue samples were taken for further microbiological and pathological examinations. On bacteriological investigation, Salmonella typhimurium and Streptococcus agalactiae were isolated. Histopathologically, lesions consisted of hyperemia and hemorrhage in all serosal and mucosal surfaces, gastroenteritis, and purulent ascites, associated with suppurative omphalitis. Acute nutmeg liver demonstrated centrilobular congestion and moderate fatty changes without any inflammatory cell infiltration. The abomasal and intestinal mucosa were hemorrhagic and erosive. The brain was hyperemic with severe fibrinopurulent meningoencephalitis. Except for dromedary camels and llamas, there has been no previous report of an acute, fatal septicemia in a two-humped camel calf due to S. typhimurium accompanied by S. agalactiae.  相似文献   
86.
The effects of irradiance and photoperiod on the biomass and fatty acid (FA) composition of Chlorella vulgaris were examined in the exponential growth phase. Results indicated significant differences in biomass and FA at different intensities and photoperiods. Maximum biomass (2.05 ± 0.1 g l−1) was at 62.5 μmol photons m−2 s−1 and 16:8 h light/dark photoperiod. FA composition changed considerably in different light regimes; the maximum percentage of total saturated (SFA) (33.38%) was recorded at 100 μmol photons m−2 s−1 and 16:8 h photoperiod, while monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids decreased with increasing irradiance and light duration. The maximum percentage of total MUFA (15.93%) and PUFA (27.40%) was recorded at 37.5 μmol photons m−2 s−1 and 8:16 h photoperiod.  相似文献   
87.
This study was conducted to investigate the effects of different levels of dietary vitamin C on some skin mucus immune parameters, mucus antimicrobial activity and growth performance of Caspian roach (Rutilus rutilus caspicus) fry. Six hundred sixty Caspian roach (1.4 ± 0.02 g) fry were allocated to 12 tanks (55 fish per tank), and triplicate groups were fed diets containing 0, 1,000, 1,500 and 2,000 mg kg?1 vitamin C for 60 days. At the end of the trial, the epidermal mucus protein level, alkaline phosphatase and antimicrobial activity against two gram-positive bacteria (Streptococcus faecium and Micrococcus luteus) and gram-negative bacteria (Escherichia coli and Serratia marcescens) as well as growth performance were measured. The results demonstrated that feeding on vitamin C significantly elevated skin mucus alkaline phosphatase and protein levels compared to the control group (P < 0.05). However, lysozyme activity was undetectable in both the vitamin C-fed roach fry and the control group. Skin mucus antimicrobial activity was increased following vitamin C administration, and the bacterial growth inhibition zones were significantly elevated in vitamin C-fed roach (P < 0.05). Similar results were obtained in case of the minimum inhibitory concentration of skin mucus. Also fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). These results revealed that dietary vitamin C beneficially affects the skin mucus immune parameters and growth performance of Caspian roach fry.  相似文献   
88.

Background:

Ovarian tissue cryopreservation is an alternative strategy to preserve the fertility of women predicted to undergo premature ovarian failure. This study was designed to evaluate the expression of folliculogenesis-related genes, including factor in the germline alpha (FIGLA), growth differentiation factor-9 (GDF-9), follicle-stimulating hormone receptor (FSHR), and KIT LIGAND after vitrification/warming of human ovarian tissue.

Methods:

Human ovarian tissue samples were collected from five transsexual women. In the laboratory, the ovarian medullary part was removed by a surgical blade, and the cortical tissue was cut into small pieces. Some pieces were vitrified and warmed and the others were considered as non-vitrified group (control). Follicular normality was assessed with morphological observation by a light microscope, and the expression of FIGLA, KIT LIGAND, GDF-9,, and FSHR genes was examined using real-time RT-PCR in both the vitrified and non-vitrified groups.

Results:

Overall, 85% of the follicles preserved their normal morphologic feature after warming. The percentage of normal follicles and the expression of FIGLA, KIT LIGAND, GDF-9, and FSHR genes were similar in both vitrified and non-vitrified groups (P > 0.05).

Conclusion:

Vitrification/warming of human ovarian tissue had no remarkable effect on the expression of folliculogenesis-related genes. Key Words: Vitrification, Gene expression, Humans  相似文献   
89.
Potassium (K) is one of the major essential nutrient elements whose application of organic or nano-chelate-fertilizers has received increased attention recently. Cadmium (Cd) contamination in agricultural soils and environment is increasing due to the over-application of Cd-containing phosphate fertilizers. But few studies have been carried out on the environmental influences of K-nano-chelate fertilizers especially on Cd-polluted soils. Therefore, the effects of K-fertilizer application in different rates (0, 100 and 200 mg kg?1 soil) and forms (KCl, K2SO4 and K-nano-chelate) on Cd content and partitioning in Ocimum basilicum grown on an artificially Cd-contaminated calcareous soil (with 40 mg Cd kg?1 soil) were studied under greenhouse conditions. Cadmium decreased shoot dry weight (SDW), but did not affect root dry weight (RDW) and no consistent trend was observed with applied K. Cadmium increased shoot and root Cd concentration or uptake. KCl and K2SO4 increased shoot Cd concentration compared to that of control, whereas K-nano-chelate did not affect it. In Cd-treated soils the mean value of Cd translocation factor (ratio of Cd concentration in shoots to that of roots) decreased by 60% as compared to that of the control. Application of 100 mg K-K2SO4 and 100 and 200 mg K-nano-chelate increased the Cd translocation factor by 49, 59 and 112% in Cd-treated soils, respectively. In Cd-treated soils, greater amounts of Cd accumulated in roots. K-nano-chelate could mitigate the adverse effect of Cd on SDW and Cd accumulation in plants grown on Cd-polluted soils, so the risk of Cd entrance to the food chain is reduced (however, in Cd-untreated soils, K-nano-chelate increased the Cd translocation factor higher than other K sources). In Cd-polluted soils KCl was the most inappropriate fertilizer that may intensify Cd accumulation in plants. However, it may be useful in the phytoremediation of Cd-polluted soils.  相似文献   
90.
The study aims at performing a comparative assessment of two types of burn wound treatment. The present study was designed to prepare crosslinked and blended two natural polymers nanofiber scaffolds using gelatin (GE) and hyaluronic acid (HA). The GE/HA composite nanofibrous membranes with varied GE/HA weight ratio have also been successfully fabricated by an electrospinning method. The average diameter of GE/HA fibers was in the range of 20 to 150 nm. In vivo efficacy was also investigated based on a deep second degree burns model for Wistar rats. At 14 days post-operation, the dermal defect basically recovered its normal condition. A percentage of wound closure of GE/HA composite nanofibrous membranes and ChitoHeal gel reached up to 81.9 % and 77.8 % respectively, compared with 65 % of the untreated control (p<0.05). Also, histological parameters were assessed on postoperative day 7 and 14. The results of in vivo experiments showed that more epidermis was formed in the gel and scaffold groups compared to the control group. The numbers of inflammatory cells in these two groups were also smaller as compared with the control group, which could well be the reason for the delayed healing in the control group.  相似文献   
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