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131.
目的:研究黄豆提取物对经戊四唑(pentylenetrazole,PTZ)诱发癫病发作的女性荷尔蒙缺失雌性大鼠与正常雌性大鼠的不同作用,以及因性别差异引起的植物雌性激素对行为的影响。方法:雄性Wistar大鼠被随机分为雄性生理盐水组,雄性低、中、高剂量黄豆提取物治疗组,每组8只;雌性Wistar大鼠随机分为假手术生理盐水组,假手术低、中、高剂量黄豆提取物治疗组,去卵巢生理盐水组,去卵巢低、中、高剂量黄豆提取物治疗组,每组8只。去卵巢大鼠在氯胺酮麻醉下行卵巢切除术。分别给予各组大鼠生理盐水及不同剂量黄豆提取物治疗2周后腹腔内注射戊四唑。将大鼠放置在树脂玻璃笼内,记录最小阵挛性癫痫发作(minialclonicseizure,MCS)潜伏期和强直性阵挛性癫痫发作(generalizedtonic-clonicseizure,GTCS)潜伏期。结果:与雄性生理盐水组大鼠比较,雄性低、中剂量黄豆提取物治疗组的MSC和GTCS潜伏期显著缩短(P〈10.05或P〈0.01)。雌性假手术大鼠在给予黄豆提取物治疗后,其MSC和GTCS潜伏期没有显著改变。与去卵巢生理盐水组比较,去卵巢低、高剂量黄豆提取物治疗组的MSC和GTCS潜伏期明显缩短(P〈0.05或P〈0.01)。结论:黄豆的植物雌激素能影响由PTZ诱发的癫痫发作的轻重程度,但其影响程度与卵巢激素水平有关。机制还有待进一步研究。 相似文献
132.
Research on plant viruses in natural ecosystems has been increasing rapidly over the past decade. This paper reviews recent research on the barley and cereal yellow dwarf viruses (B/CYDVs) in grasslands of the western US, beginning with the evidence that the disease caused by these viruses facilitated the invasion of western US grasslands by European annual grasses. Observational and experimental studies of B/CYDVs were carried out along a latitudinal gradient (33.8-48.8°N) from southern California to southern Canada. The prevalence and community composition of B/CYDVs were assessed over a variety of scales and under a range of biotic and abiotic conditions. The findings indicate that both biotic and abiotic factors are important influences on virus ecology and epidemiology. Introduced annual grasses are high-quality hosts that amplify both virus and vector populations in this system, but our research suggests that endemic perennial grasses are critically important for sustaining virus populations in contemporary grasslands largely composed of introduced species. Experiments indicated that increased phosphorus supply to hosts resulted in greater host biomass and higher virus prevalence. Using experimental exclosures, it was found that the presence of grazing vertebrate herbivores increased the abundance of annual grasses, resulting in increased virus prevalence. The results of these studies suggest that patterns of B/CYDV prevalence and coinfection in western US grasslands are strongly shaped by the interactions of host plants, vectors, vertebrate herbivores, and abiotic drivers including nutrients. 相似文献
133.
Pirzad Jahromi G Seidi S Sadr SS Shabanzadeh AP Keshavarz M Kaka GR Hosseini SK Sohanaki H Charish J 《Basic & clinical pharmacology & toxicology》2012,110(6):487-493
In this study, we investigated the therapeutic effects of simvastatin administered in combination with bone marrow stromal cells (BMSCs) following experimentally induced embolic stroke in rats. Effects on infarct volume, brain oedema and neurological deficits were examined. Focal ischaemic brain injury was induced by emblazing a preformed clot into the middle cerebral artery in rats. Animals were administered simvastatin (40 mg/kg) at 1 hr after stroke, or BMSCs (3 × 10(6)) at 24 hr after stroke or a combination of these two treatments. Rats receiving a dose of simvastatin in combination with BMSC administration demonstrated a significant reduction in neurological deficits, a significant reduction in infarct volume and a significant decrease in brain oedema. Our data show that combining simvastatin administration with BMSCs has an additive effect on improving functional outcome in this thromboembolic stroke model. 相似文献
134.
Chen XT Chan ST Hosseini H Layton D Boyd R Alderuccio F Toh BH Chan J 《Autoimmunity》2011,44(5):384-393
Transplantation of bone marrow (BM) engineered to express self-antigen has been shown to protect 100% of young mice from myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE), with thymic clonal deletion as a tolerance mechanism. Here, we asked whether aged mice can also be tolerised following transplantation with self-antigen-engineered BM and whether castration-induced thymus regrowth can enhance this outcomes. Then, 50% of aged mice were protected from EAE regardless of castration-induced thymus regrowth. EAE-free and diseased mice demonstrated MOG-specific lymphocyte proliferation and antibody production regardless of castration-induced thymus regrowth, consistent with lack of intrathymic deletion of self-antigen-reactive T cells. Although low chimerism levels (?4%) were observed, EAE-free mice showed significantly higher chimerism levels in lymphocytes in peripheral lymphoid organs compared with thymus. CD4(+)CD25(+) regulatory T cells were elevated in lymph nodes of EAE-free mice. We conclude that transplantation of self-antigen expressing BM protects 50% of aged mice and castration-induced thymic regrowth had no effect on outcomes. Peripheral tolerance mechanisms are implicated since protection is associated with higher chimerism levels in peripheral T and B lymphocytes and with elevated regulatory T cells. 相似文献
135.
Mahmoud Hosseini Hamid Reza Sadeghnia Soodabeh Salehabadi Hassan Alavi Ali Gorji 《Seizure》2009,18(10):695-698
The role of ovarian hormones and nitric oxide (NO) on seizure and their interaction have been widely investigated. The present study carried out to evaluate the effect of chronic administration of l-arginine (lA) and l-NAME (lN) on pentylenetetrazole (PTZ) induced epilepsy in ovariectomized (OVX) and naïve female rats.Fourty-eight female rats were randomly divided into six groups (n = 8) as follows: (1) sham, (2) ovarectomized (OVX), (3) sham-lA, (4) sham-lN, (5) OVX-lA, and (6) OVX-lN.The animals of sham-lA and OVX-lA received daily injection of 500 mg/kg l-arginine (i.p.) during 4 weeks. Sham-lN and OVX-lN were treated by 10 mg/kg l-NAME (i.p.) daily for 4 weeks. The animals of sham and OVX groups received 1 ml/kg saline (i.p.) instead of l-arginine and l-NAME. The latencies to minimal clonic seizures (MCS) and generalized tonic–clonic seizures (GTCS) after intraperitoneal injection of penetylenetetrazole (PTZ, 90 mg/kg) was recorded and compared between groups.A significant increase in the GTCS, but not MCS, latency was seen in OVX rats in comparison with sham-operated animals. Pretreatment of animals with l-NAME resulted in a significant increase in the GTCS and MCS latencies in sham group while no significant effects were seen in OVX rats. On the contrary, while pretreatment with l-arginine had no effects on MCS and GTCS latencies in sham group, a significant decrease in GTCS latency was observed in OVX rats.It is concluded that ovarian sex hormones affect seizure thresholds induced by PTZ and NO has a role on seizures susceptibility following PTZ administration. This NO effect might be differing in the presence or absence of ovarian hormones, but further investigations need to be done. 相似文献
136.
137.
Vitamin C reduces spatial learning deficits in middle-aged and very old APP/PSEN1 transgenic and wild-type mice 总被引:1,自引:0,他引:1
F.E. Harrison A.H. Hosseini M.P. McDonald J.M. May 《Pharmacology, biochemistry, and behavior》2009,93(4):443-450
Alzheimer's disease is a progressive and fatal neurodegenerative disease characterized by a build up of amyloid β (Aβ) deposits, elevated oxidative stress, and deterioration of the cholinergic system. The present study investigated short-term cognitive-enhancing effects of acute intraperitoneal (i.p.) Vitamin C (ascorbate) treatment in APP/PSEN1 mice, a mouse model of Alzheimer's disease. Middle-aged (12 months) and very old (24 months) APP/PSEN1 bigenic and wild-type mice were treated with ascorbate (125 mg/kg i.p.) or the vehicle 1 h before testing on Y-maze spontaneous alternation and Morris water maze tasks. Very old mice performed more poorly on cognitive tasks than middle-aged mice. Ascorbate treatment improved Y-maze alternation rates and swim accuracy in the water maze in both wild-type and APP/PSEN1 mice. Aβ deposits and oxidative stress both increased with age, and acetylcholinesterase (AChE) activity was significantly reduced in APP/PSEN1 compared to wild-type mice. However, the short course of acute ascorbate treatment did not alter Alzheimer-like neuropathological features of plaque deposition, oxidative stress, or AChE activity. These data suggest that ascorbate may have noötropic functions when administered parenterally in high doses and that the mode of action is via an acute, pharmacological-like mechanism that likely modulates neurotransmitter function. 相似文献
138.
Hosseini-Farahabadi S Tavakkol-Afshari J Rafatpanah H Farid Hosseini R Khaje Daluei M 《Iranian journal of allergy, asthma, and immunology》2007,6(1):9-14
Allergic asthma is a multifactorial disease, influenced by genetic and environmental factors. Recent family-based studies have revealed evidence for linkage of human chromosomes 5q31-33, 12q15-24, 11q13 and 15q23.6 as regions likely to contain genes related to asthma. Among the candidate genes in these regions are the genes encoding for human interleukin-4, interleukin-13 and interleukin-16. To evaluate this linkage, we examined an Iranian population of patients with asthma. A total of 30 patients with allergic asthma and 50 normal subjects were studied. Allergic asthma was confirmed using skin prick test and spirometry. DNA was extracted from blood cells and IL-4 (-590C>T), IL-13 (R130Q) and IL-16 (-295T>C) polymorphisms were determined by PCR-RFLP method. Out of 30 patients with allergic asthma, the following genotypes for IL-4, IL-13 and IL-16 cytokines were found: IL-4 genotypes consisted of 17 (56.7%) CC, 8 (26.7%) CT and 5 (16.7%) TT; IL-13 genotypes consisted of 11 (36.7%) GG, 13 (43.3%) GA and 6 (20%) AA; IL-16 genotypes consisted of 23 (76.7%) TT and 7 (23.3%) CT. No patient showed CC genotype for IL-16. A higher proportion of case subjects with the C allele for the IL-4, G allele for the IL-13 and T allele for the IL-16 polymorphisms was found compared with the T, A and C alleles, respectively. These results suggest an influence of genetic variability at the promoter of IL-4 gene (-590C>T) and a coding region of IL-13 gene (R130Q) on the occurrence of allergic asthma and no relationship between IL-16 promoter polymorphism (-295T>C) and this disease. 相似文献
139.
140.
Xesús Fes Lei Ye Seyed V. Hosseini Cristina A. Fente Alberto Cepeda 《Journal of pharmaceutical and biomedical analysis》2009,50(5):1044-1049
A rapid and sensitive liquid chromatographic–tandem mass spectrometric (LC–MS/MS) method was developed and validated for the qualitative and quantitative assay of cyproheptadine (CP) in pharmaceutical samples. Diphenylpyraline hydrochloride (DPP) was used as an internal standard (IS). Two multiple reaction-monitoring (MRM) transitions for each analyte were observed: 288.1/96.1 and 288.1/191.2 for CP and 282.1/167.2 and 282.1/116.3 for DPP. The retention time of the drug was 7.29 min. The analytical method was successfully validated for linearity (1–100 ng/ml), intra-day precision, inter-day precision, and accuracy. The limit of detection (LOD) and limit of quantification (LOQ) were 0.86 and 0.98 ng/ml, respectively. The proposed method was applied to analyse the cyproheptadine content from seven different syrup formulations. 相似文献