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101.
The purpose of this study was to evaluate the levels of Zinc, Copper, Iron and Copper/Zinc ratio in the serum of adult patients with pulmonary tuberculosis in Iran. Serum levels of Zinc and Copper were determined by flame atomic absorption spectrophotometer and scrum iron concentration was measured by using an Auto Analyzer. The study group consisted of 50 pulmonary tuberculosis patients before treatment and after 6 months of anti-tubercular therapy. Levels of scrum Zn (p < 0.001) and Fe (p < 0.001) in TB patients were significantly increased after 6 months of anti-tubercular therapy. However, serum Cu concentration (p < 0.01) and Cu/Zn ratio (p < 0.05) were decreased after 6 months of anti-tubercular therapy. Some studies indicated a strong association of Zn, Cu, Fe and the Cu/Zn ratio with TB. In this study, we found remarkable change in Cu/Zn ratio. Some researchers mentioned that serum Cu/Zn ratio could be used as an important laboratory marker for diagnosis and treatment of tuberculosis. They also mentioned that trace element levels must be closely monitored during the process of disease.  相似文献   
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103.
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   
104.
Background:One of the main challenges with conventional scaffold fabrication methods is the inability to control scaffold architecture. Recently, scaffolds with controlled shape and architecture have been fabricated using 3D-printing. Herein, we aimed to determine whether the much tighter control of microstructure of 3DP PLGA/β-TCP scaffolds is more effective in promoting osteogenesis than porous scaffolds produced by solvent casting/porogen leaching. Methods:Physical and mechanical properties of porous and 3DP scaffolds were studied. The response of pre-osteoblasts to the scaffolds was analyzed after 14 days. Results:The 3DP scaffolds had a smoother surface (Ra: 22 ± 3 µm) relative to the highly rough surface of porous scaffolds (Ra: 110 ± 15 µm). Water contact angle was 112 ± 4° on porous and 76 ± 6° on 3DP scaffolds. Porous and 3DP scaffolds had the pore size of 408 ± 90 and 315 ± 17 µm and porosity of 85 ± 5% and 39 ± 7%, respectively. Compressive strength of 3DP scaffolds (4.0 ± 0.3 MPa) was higher than porous scaffolds (1.7 ± 0.2 MPa). Collagenous matrix deposition was similar on both scaffolds. Cells proliferated from day 1 to day 14 by fourfold in porous and by 3.8-fold in 3DP scaffolds. ALP activity was 21-fold higher in 3DP scaffolds than porous scaffolds. Conclusion:The 3DP scaffolds show enhanced mechanical properties and ALP activity compared to porous scaffolds in vitro, suggesting that 3DP PLGA/β-TCP scaffolds are possibly more favorable for bone formation. Key Words: Alkaline phosphatase, β-tricalcium phosphate, Poly(lactic-co-glycolic) acid copolymer  相似文献   
105.
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   
106.
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   
107.
Fruit traits and molecular markers (RAPD) were used to survey genetic similarities and inheritance pattern of offspring, derived from self- and open pollination of pomegranate cv. Malase-Tourshe-Saveh (MTS) as well as progenies derived from cross between ‘MTS’ and ‘Narm-Daneh’ (ND) a soft-seed cultivar in the present study. Clustering based on fruit traits, divided the accessions firstly into two major groups, sweets and sour or sweet–sours. Members of sub-clusters were different in fruit characters, and seed softness also was affecting the grouping of individuals. Offspring of ‘MTS’ × ’ND’ showed somehow seed softness with varying degrees compared to other individuals. In RAPD analysis, by using 26 polymorphic primers, 325 fragments were produced from 39 individuals, among which 70 reproducible, polymorphic bands were scored for data analysis. NTsys and Bootstrap software were used for RAPD data analysis and respective dendrogram depicted by Jaccard's similarity coefficients using UPGMA method. The similarity coefficients were ranging from 0.2 to 0.94 and the lowest was obtained between pollen parent (ND cv.) and a genotype from open pollination of MTS cultivar. The highest similarity coefficient (0.94) was observed between two offspring both from self-pollination of MTS cultivar. In corresponding dendrogram, pollen parent was separated from other genotypes and laid individually in a sub-cluster, while the mother plant clustered with its progenies. In addition, some marker–trait associations were observed, especially for seed softness.  相似文献   
108.
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   
109.
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   
110.
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   
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