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991.
Yazdi MH Mahdavi M Varastehmoradi B Faramarzi MA Shahverdi AR 《Biological trace element research》2012,149(1):22-28
Selenium salts as well as elemental selenium nanoparticles are attracting the attention of researchers due to their excellent biological properties. The aim of the present work was to study immunomodulation by applying elemental Se NPs to stimulate the immune response of mice bearing 4?T1 breast cancer tumors. Six- to 8-week-old female inbred BALB/c mice were divided into two groups of test and control, each containing 15 mice. Every day, for 2?weeks prior to tumor induction, selenium nanoparticles were orally administered to the mice at a dose of 100?μg/day. Then, 1?×?10(6) cells from a 4?T1 cell line were injected subcutaneously to each mouse. Oral nanoparticle administration was continued daily for 3?weeks after tumor induction. Different immunological parameters were then evaluated including cytokine level, delayed type hypersensitivity (DTH) response as well as tumor growth and the survival rates in all treated or nontreated animals. The production of Th1 cytokines, such as IFN-γ and IL-12, in spleen cell culture was increased in the test mice-administered selenium nanoparticles. The DTH response of test mice also showed a significant increase when compared to the control mice. The survival rate was notably higher for the selenium nanoparticle-treated mice compared to the control mice. Our results suggest that selenium nanoparticle administration can result in considerable induction of the Th1 platform of immune response through the elevation of IFN-γ and IL-12 and may be a cause for better prognosis in mice with tumors. 相似文献
992.
Pajouhesh H Feng ZP Zhang L Pajouhesh H Jiang X Hendricson A Dong H Tringham E Ding Y Vanderah TW Porreca F Belardetti F Zamponi GW Mitscher LA Snutch TP 《Bioorganic & medicinal chemistry letters》2012,22(12):4153-4158
We previously reported the small organic N-type calcium channel blocker NP078585 that while efficacious in animal models for pain, exhibited modest L-type calcium channel selectivity and substantial off-target inhibition against the hERG potassium channel. Structure-activity studies to optimize NP078585 preclinical properties resulted in compound 16, which maintained high potency for N-type calcium channel blockade, and possessed excellent selectivity over the hERG (~120-fold) and L-type (~3600-fold) channels. Compound 16 shows significant anti-hyperalgesic activity in the spinal nerve ligation model of neuropathic pain and is also efficacious in the rat formalin model of inflammatory pain. 相似文献
993.
Mehri S Abnous K Mousavi SH Shariaty VM Hosseinzadeh H 《Cellular and molecular neurobiology》2012,32(2):227-235
Acrylamide (ACR) is a potent neurotoxic in human and animal models. In this study, the effect of crocin, main constituent
of Crocus sativus L. (Saffron) on ACR-induced cytotoxicity was evaluated using PC12 cells as a suitable in vitro model. The exposure of PC12
cells to ACR reduced cell viability, increased DNA fragmented cells and phosphatidylserine exposure, and elevated Bax/Bcl-2
ratio. Results showed that ACR increased intracellular reactive oxygen species (ROS) in cells and ROS played an important
role in ACR cytotoxicity. The pretreatment of cells with 10–50 μM crocin before ACR treatment significantly attenuated ACR
cytotoxicity in a dose-dependent manner. Crocin inhibited the downregulation of Bcl-2 and the upregulation of Bax and decreased
apoptosis in treated cells. Also, crocin inhibited ROS generation in cells exposed to ACR. In conclusion, our results indicated
that pretreatment with crocin protected cells from ACR-induced apoptosis partly by inhibition of intracellular ROS production. 相似文献
994.
Sayed Mohammad Masoumi Danial Kahrizi Hossein Rostami-Ahmadvandi Jahad Soorni Sara Kiani Ali Mostafaie Kheirollah Yari 《Molecular biology reports》2012,39(12):10361-10365
Cumin (Cuminum cyminum L.), Fennel (Foeniculum vulgare L.) and Longleaf (Falcaria vulgaris Bernh) that all belong to Apiaceae family as medicinal plants are very important in many countries. Study of genetic diversity for medicinal plant is important for researches in future. One of the methods to evaluate plant genetic diversity and classification of them is the electrophoresis of seed storage proteins. This research was conducted in order to evaluate seed protein variability in different Iranian Cumin, Fennel and Longleaf accessions and grouping them based on these proteins as a biochemical marker. For this purpose, the samples were first powdered in liquid nitrogen and seed protein was extracted with extraction buffer. Then total soluble proteins were resolved on 12.5?% sodium dodecyl sulphate polyacrylamide gel electrophoresis gels. The electrophoretic protein pattern showed 38 bands that were low polymorphism among the accessions. The result of cluster analysis showed that the accessions were classified in three groups (all 29 Cumin accessions in the first group, three Fennel ecotypes in second group and three Longleaf accessions in the last one). 相似文献
995.
Hossein Nejadnik Tobias D. Henning Thuy Do Elizabeth J. Sutton Frederick Baehner Andrew Horvai Barbara Sennino Donald McDonald Reinhard Meier Bernd Misselwitz Thomas M. Link Heike E. Daldrup-Link 《PloS one》2012,7(12)
Objectives
The purpose of our study was to assess the chondrogenic potential and the MR signal effects of GadofluorineM-Cy labeled matrix associated stem cell implants (MASI) in pig knee specimen.Materials and Methods
Human mesenchymal stem cells (hMSCs) were labeled with the micelle-based contrast agent GadofluorineM-Cy. Ferucarbotran-labeled hMSCs, non-labeled hMSCs and scaffold only served as controls. Chondrogenic differentiation was induced and gene expression and histologic evaluation were performed. The proportions of spindle-shaped vs. round cells of chondrogenic pellets were compared between experimental groups using the Fisher''s exact test. Labeled and unlabeled hMSCs and chondrocytes in scaffolds were implanted into cartilage defects of porcine femoral condyles and underwent MR imaging with T1- and T2-weighted SE and GE sequences. Contrast-to-noise ratios (CNR) between implants and adjacent cartilage were determined and analyzed for significant differences between different experimental groups using the Kruskal-Wallis test. Significance was assigned for p<0.017, considering a Bonferroni correction for multiple comparisons.Results
Collagen type II gene expression levels were not significantly different between different groups (p>0.017). However, hMSC differentiation into chondrocytes was superior for unlabeled and GadofluorineM-Cy-labeled cells compared with Ferucarbotran-labeled cells, as evidenced by a significantly higher proportion of spindle cells in chondrogenic pellets (p<0.05). GadofluorineM-Cy-labeled hMSCs and chondrocytes showed a positive signal effect on T1-weighted images and a negative signal effect on T2-weighted images while Ferucarbotran-labeled cells provided a negative signal effect on all sequences. CNR data for both GadofluorineM-Cy-labeled and Ferucarbotran-labeled hMSCs were significantly different compared to unlabeled control cells on T1-weighted SE and T2*-weighted MR images (p<0.017).Conclusion
hMSCs can be labeled by simple incubation with GadofluorineM-Cy. The labeled cells provide significant MR signal effects and less impaired chondrogenesis compared to Ferucarbotran-labeled hMSCs. Thus, GadoflurineM-Cy might represent an alternative MR cell marker to Ferucarbotran, which is not distributed any more in Europe or North America. 相似文献996.
Aliakbar Rajabzadeh Alireza Ebrahimzadeh Bideskan Alireza Fazel Mojtaba Sankian Houshang Rafatpanah Hossein Haghir 《Journal of biomedical science》2012,19(1):56
Background
Maternal epileptic seizures during pregnancy can affect the hippocampal neurons in the offspring. The polysialylated neural cell adhesion molecule (PSA-NCAM), which is expressed in the developing central nervous system, may play important roles in neuronal migration, synaptogenesis, and axonal outgrowth. This study was designed to assess the effects of kindling either with or without maternal seizures on hippocampal PSA-NCAM expression in rat offspring.Methods
Forty timed-pregnant Wistar rats were divided into four groups: A) Kind+/Seiz+, pregnant kindled (induced two weeks prior to pregnancy) rats that received repeated intraperitoneal (i.p.) pentylenetetrazol, PTZ injections on gestational days (GD) 14-19; B) Kind-/Seiz+, pregnant non-kindled rats that received PTZ injections on GD14-GD19; C) Kind+/Seiz-, pregnant kindled rats that did not receive any PTZ injections; and D) Kind-/Seiz-, the sham controls. Following birth, the pups were sacrificed on PD1 and PD14, and PSA-NCAM expression and localization in neonates’ hippocampi were analyzed by Western blots and immunohistochemistry.Results
Our data show a significant down regulation of hippocampal PSA-NCAM expression in the offspring of Kind+/Seiz+ (p = 0.001) and Kind-/Seiz+ (p = 0.001) groups compared to the sham control group. The PSA-NCAM immunoreactivity was markedly decreased in all parts of the hippocampus, especially in the CA3 region, in Kind+/Seiz+ (p = 0.007) and Kind-/Seiz+ (p = 0.007) group’s newborns on both PD1 and 14.Conclusion
Our findings demonstrate that maternal seizures but not kindling influence the expression of PSA-NCAM in the offspring’s hippocampi, which may be considered as a factor for learning/memory and cognitive impairments reported in children born to epileptic mothers. 相似文献997.
Sheikhzadeh N Karimi Pashaki A Nofouzi K Heidarieh M Tayefi-Nasrabadi H 《Fish & shellfish immunology》2012,32(3):407-410
The effects of dietary Ergosan on the growth performance and mucosal immunity in rainbow trout skin were investigated. 60 rainbow trout (100-110 g) were randomly assigned to 2 groups in triplicates and fed one of the experimental diet formulated with 5 g kg−1 Ergosan or control diet for 50 days. Results showed that on the 45th day of feeding trial, Ergosan supplementation significantly enhanced the growth performance compared to control group. Various enzyme activities, namely lysozyme, protease, alkaline phosphatase and esterase in treatment group were also enhanced on the 45th and 50th day. Skin mucus in Ergosan-fed fish showed the agglutination of erythrocytes while in control group, no visible agglutination was shown. In addition, skin mucus in treatment group showed strong antibacterial activity against Yersinia ruckeri. In conclusion, the major immune components of rainbow trout mucus that are involved in the non-specific immunity were enhanced by administration of Ergosan in 5 g kg−1. 相似文献
998.
Background: Helicobacter pylori eradication has still remained a challenge, especially in case of failure to novel treatments. Therefore, we designed a study to evaluate the effects of a modified bismuth‐containing quadruple therapy including a short course of furazolidone on a group of patients whose sequential therapy had been unsuccessful. Materials and Methods: Thirty‐six H. pylori‐positive patients who had previously failed a clarithromycin‐containing sequential therapy enrolled the study. They received pantoprazole (40 mg‐bid), amoxicillin (1 g‐bid), and bismuth subcitrate (240 mg‐bid) for 2 weeks and furazolidone (200 mg‐bid) just during the first week. Eight weeks after treatment, H. pylori eradication was reassessed using C14‐urea breath test. Results: Thirty five patients completed the study. H. pylori eradication rates were 80.6% (95% CI = 67.6–93.5) and 82.9% (95% CI = 70.6–95.2) according to intention‐to‐treat and per‐protocol analyses, respectively. All patients had excellent compliance to treatment, and no one interrupted therapy owing to adverse effects. Conclusion: Regarding the eradication rate (>80%), low price, and very low adverse effects, a 2‐week bismuth‐containing quadruple regimen including a short course of furazolidone can be an encouraging regimen for second‐line H. pylori eradication in case of sequential therapy failure. Possibly, it can be improved by alterations in dose, dosing intervals, and/or duration. 相似文献
999.
Yeganeh LP Azarbaijani R Sarikhan S Mousavi H Ramezani M Amoozegar MA Fazeli AS Salekdeh GH 《Journal of bacteriology》2012,194(8):2123-2124
Oceanimonas sp. GK1 (IBRC-M 10197) is a marine halotolerant gammaproteobacterium which was characterized as producing large amounts of poly-β-hydroxybutyrate. Here we present the whole-genome sequence of Oceanimonas sp. GK1, which consists of a single circular chromosome of 3,514,537 bp and two plasmids 8,462 and 4,245 bp in length. 相似文献
1000.
Reza?Kachuei Mohammad Hossein?Yadegari?Email author Sasan?Rezaie Abdolamir?Allameh Naser?Safaie Farideh?Zaini Fatemeh?Khanezad?Yazdi 《Annals of microbiology》2009,59(2):383
Wheat is the most important cereal produced in Iran. A mycological survey was carried out for the first time, on the stored wheat samples in Tehran, East Azarbayejan and Mazandaran provinces in 2007. Exogenous and endogenous fungi, were isolated by the method of flotation with Malachite green agar (MGA 0.25) and Freeze blotter techniques respectively. In this study, 46 species belonging to 23 different genera were isolated.Cladosporium spp. (57.1–89.2%) andAlternaria spp. (82.4–100%) species were the predominant fungal species identified as endogenous mycoflora. The predominant exogenous fungi werePenicillium spp. (78.4–92.8%) andAspergillus spp. (71.4–85.7%) species.Fusarium proliferatum was the most prevalent species ofFusarium isolates.Aspergillus niger (39.4%) andAspergillus flavus (36.7%) were the predominantAspergillus species identified as exogenous mycoflora.Aspergillus flavus (26.6%) was the predominantAspergillus species identified as endogenous mycoflora. Flotation method with MGA 0.25 recommended for isolating of hyaline fungi from wheat cereals. In this study one isolate fromFusarium species was isolated on the basis of morphology and ribosomal internal transcribed spacer classified asFusarium langsethiae but on the basis of partial translation elongation factor-1alpha gene grouped withFusarium sporotrichioides. To our knowledge, this is the first report aboutF. cf.langsethiae in Iran and Asia. 相似文献