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991.
The inhibitory effects of mycobacterial infection and mycobacterium components on multiple sclerosis (MS) and experimental autoimmune encephalitis (EAE; an animal model for MS) have been known for years. However, this effect seems like a paradox that both mycobacterial infection and MS induce type I immune responses. Some mechanisms have been proposed or even proven for this effect in different studies, but among them there is no hint of a possible role for the nervous system (NS). Regarding the close relations between sympathetic nervous system (SNS) and MS disease course, it can be hypothesized that SNS may have a role in the effects of mycobacterium on MS. Hypothesis: SNS can be stimulated by pro-inflammatory cytokines such as TNF-alpha and IL1-beta, production of which are induced by mycobacterial infection or mycobacterium components. Although these cytokines can inhibit SNS in the site of inflammation caused by mycobacterium, they increase sympathetic tone in other places. The beneficial role of SNS in inhibiting or attenuating the course of MS and EAE has been suggested. Inhibitory effects of stimulated SNS on MS may occur via different ways such as inhibiting the production of pro-inflammatory cytokines and inducing the synthesis of anti-inflammatory cytokines, in other words, shifting the immune responses from type 1 toward type 2, as well as, induction of suppressor/regulator T lymphocytes, induction of heat shock proteins in brain and increasing the expression of Fas and Fas-ligand. Therefore, it seems that stimulation of SNS by mycobacterial infection or mycobacterium components is a key step in the mechanism of beneficial effects of mycobacterium on MS. 相似文献
992.
Age-related macular degeneration (ARMD) is the foremost cause of blindness among the elderly population in industrialised countries. Currently, there is no effective treatment for the majority of patients. To develop new and effective modes of therapy, understanding of the molecular basis of the disease is mandatory. Many age-related pathologies have been attributed to cumulative oxidative damage caused by reactive oxygen intermediates. There is growing evidence that uric acid has antioxidant properties and it is a naturally occurring antioxidant. Based on antioxidant role in pathogenesis of ARMD and antioxidant properties of uric acid we conclude that altered uric acid metabolism could play a role in ARMD damage and pathogenesis. Future research needs to evaluate uric acid metabolism in ARMD patients. 相似文献
993.
A novel accurate ACRS-PCR method with a digestion internal control for identification of wild type and YMDD mutants of hepatitis B virus strains 总被引:1,自引:0,他引:1
Hosseini SY Sabahi F Amini-Bavil-Olyaee S Alavian SM Merat S 《Journal of virological methods》2006,137(2):298-303
As a consequence of the point mutation in the YMDD motif of the hepatitis B virus (HBV) polymerase gene, lamivudine-resistant mutants have been reported in chronic hepatitis B patients who underwent lamivudine therapy. The objective of the study was to develop a novel accurate artificially created restriction site (ACRS) method with a digestion internal control for identification of YMDD, YIDD and YVDD HBV strains. Three conserved, specific and diagnostic primers introducing NdeI, SspI and AleI cleavage sites were designed in order to identify YMDD, YIDD and YVDD strains, respectively; while, their reverse primers also modified with the above recognition sites in order to enzyme correctness monitoring and false outcome avoiding. Thirty-two chronic hepatitis B patients who had taken lamivudine for 1-3 years and checked by the Inno-LiPA HBV DR kit, were evaluated by the ACRS method and then compared to sequencing data. The results of the ACRS method revealed the YMDD mutant strain in 20 patients, YMDD plus YIDD pattern in 1 patient, YMDD plus YVDD in 4 patients, the YIDD in 4 patients and mixed infection with each three strains in 1 patient. The sequencing and Inno-LiPA results were in agreement with the ACRS results. The novel ACRS method is a reliable, rapid and a cost-effective technique for determination of HBV strains with the wild type and YMDD mutant patterns. 相似文献
994.
Diffusion-weighted MR imaging characteristics of an acute strokelike form of multiple sclerosis 总被引:3,自引:0,他引:3
Rosso C Remy P Creange A Brugieres P Cesaro P Hosseini H 《AJNR. American journal of neuroradiology》2006,27(5):1006-1008
The characteristics of multiple sclerosis (MS) lesions on diffusion-weighted sequences and apparent diffusion coefficient (ADC) mapping at the very early phase of symptoms have not been clearly described. We report the case of a young woman who presented with a sudden pseudostroke form of MS resulting in hemiplegia and sudden aphasia. MR imaging showed a lesion of the left internal capsule with reduced ADC, which suggests an ischemic stroke. This case shows that very acute MS lesions may have reduced ADC on MR imaging, reflecting cytotoxic and not vasogenic edema. 相似文献
995.
We describe a 20-year-old male patient who presented with gingival bleeding. Physical examination showed gingival swelling of the right maxilla and loosening of the molar teeth. The initial diagnosis of gingivitis was made, but further examination revealed a lytic lesion of the maxilla. On suspicion of fibrous dysplasia, biopsy was attempted but was unsuccessful due to severe haemorrhage. Further evaluation showed palpable and audible bruit on the gingiva, which caused the suspicion of vascular malformation. Angiography was performed and demonstrated arteriovenous malformation (AVM). Embolisation therapy with polyvinyl alcohol was performed. Post-embolisation angiogram demonstrated complete obliteration of the lesion. 相似文献
996.
Oveisgharan S Shirani S Ghorbani A Soltanzade A Baghaei A Hosseini S Sarrafzadegan N 《Cerebrovascular diseases (Basel, Switzerland)》2006,22(5-6):350-354
BACKGROUND: In Iran, a Middle-East country, no disability scale has been translated and validated for use in stroke clinical trials. This study was designed to translate the Barthel Index and make its Persian translated form valid and reliable. METHODS: All items of the Barthel Index were translated into Persian. Also, the Modified Rankin Scale (MRS) was also translated to Persian. Telephone interview was used as the method of data acquisition. Two interviewers were chosen for this means in order to accelerate data gathering and measure interrater agreement. Samples were selected from Isfahan Cardiovascular Research Center's Stroke Registry Unit, a WHO collaborating center in the center of Iran. All the patients were registered as stroke or intracerebral hemorrhage (ICH). These patients were inhabitants of Isfahan Province who had suffered from stroke or ICH between 12 and 24 months before data acquisition. Chronbach's alpha, test-retest reliability, concurrent validity with MRS, interrater agreement and item analysis were done for the translated questionnaire. RESULTS: Translated questionnaires were filled by interview from 459 stroke patients. Their mean age was 68.11 +/- 11.59 years. 243 of them were male (52.9%). Cronbach's alpha was 0.9354. Spearman's correlation coefficient between translated Barthel Index scores and MRS scores was -0.912. Spearman's correlation coefficient between 2 scores, to determine test-retest reliability was 0.989. Concordance correlation to determine interrater agreement was 0.994. All corrected item-total correlations were greater than 0.5. CONCLUSIONS: The Persian translated version of the Barthel Index is a reliable and valid questionnaire for use in stroke clinical trials. 相似文献
997.
Abolfazl Kamkar Ashkan Jebelli Javan Farzad Asadi Mohammad Kamalinejad 《Food and chemical toxicology》2010
The aim of the present study was to evaluate antioxidative activities of the essential oil, methanol and water extracts of Iranian pennyroyal in vegetable oil during storage. Different concentrations (0, 200, 400, 600, 800 and 1000 ppm) of essential oil, water and methanol extracts and beta-hydroxy toluene (BHT; 200 ppm) were added to sunflower oil emulsion in the presence of cupric ions and incubated for 7 days at 60 °C. Peroxide values (PVs) and thiobarbituric acid reacting substances (TBARS) levels were measured in each day up to day of seven. Furthermore, antioxidant capacity of the essential oil and extracts were determined using DPPH and β-carotene–linoleic acid methods. Values were compared among groups in each incubation time points using ANOVA. Results showed that DPPH and β-carotene–linoleic acid assay findings on the Mentha pulegium extracts were comparable to those found on BHT. Furthermore, in all incubation time points, M. pulegium extracts lowered PVs and TBARS levels when compared to the control (p < 0.001). In this respect, water extract was more potent than the methanol extract. Essential oil did not show considerable antioxidative effect. It seems that water extract of M. pulegium is a potent antioxidant which makes it as a potential antioxidant for oil and oily products during storage. 相似文献
998.
999.
Mehdi Tavassoli Nasser Janmohammadi Akram Hosseini Soraya Khafri Seyed Mokhtar Esmaeilnejad-Ganji 《World journal of orthopedics》2019,10(9):310-326
BACKGROUND Platelet-rich plasma(PRP) and hyaluronic acid have been shown to be useful in the treatment of knee osteoarthritis. However, investigations comparing the efficacy of these two drugs together are insufficient.AIM To compare the outcomes of PRP vs hyaluronic acid injections in three groups of patients with bilateral knee osteoarthritis.METHODS This randomized controlled trial study involved 95 patients. Thirty-one subjects received a single injection of PRP(group PRP-1), 33 subjects received two injections of PRP at an interval of 3 wk(group PRP-2) and 31 subjects received three injections of hyaluronic acid at 1-wk intervals(group hyaluronic acid). The patients were investigated prospectively at the enrollment and at 4-, 8-and 12-wk follow-up with the Western Ontario and Mc Master Universities Arthritis Index(WOMAC) and Visual Analogue Scale questionnaires.RESULTS Percentages of patients experiencing at least a 30% decrease in the total score for the WOMAC pain subscale from baseline to wk 12 of the intervention were 86%,100% and 0% in the groups PRP-1, PRP-2 and hyaluronic acid, respectively(P 0.001). The mean total WOMAC scores for groups PRP-1, PRP-2 and hyaluronic acid at baseline were 63.71, 61.57 and 63.11, respectively. The WOMAC scores were significantly improved at final follow-up to 42.5, 35.32 and 57.26,respectively. The highest efficacy of PRP was observed in both groups at wk 4 with about 50% decrease in the symptoms compared with about 25% decrease for hyaluronic acid. Group PRP-2 had higher efficacy than group PRP-1. No major adverse effects were found during the study.CONCLUSION PRP is a safe and efficient therapeutic option for treatment of knee osteoarthritis.It was demonstrated to be significantly better than hyaluronic acid. We also found that the efficacy of PRP increases after multiple injections. 相似文献
1000.