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991.
992.
Kang S  Park EJ  Joe Y  Seo E  Park MK  Seo SY  Chung HY  Yoo YH  Kim DK  Lee HJ 《Endocrinology》2010,151(12):5638-5646
Recent studies have demonstrated that TNF-related apoptosis-inducing ligand (TRAIL) is a modulator of the immune response. The relation between TRAIL and type 1 diabetes (T1D) as an autoimmune inflammatory disease in vivo is relatively unknown. To explore the potential role of TRAIL in the development of T1D, we examined its in vivo effects in nonobese diabetic (NOD) mice. NOD mice at 7 wk of age were iv injected with an adenovirus carrying either human TRAIL (Ad.hTRAIL) or β-galactosidase genes. Blood glucose was monitored weekly, and the expression of hTRAIL was evaluated in plasma and liver of mice. To investigate whether hTRAIL elicits its effect through the induction of tissue inhibitor of metalloproteinase-1 (TIMP-1), we examined the concentration of plasma TIMP-1 by ELISA and the inhibition of matrix metalloproteinase (MMP) by gelatin zymography. Here, we show that Ad.hTRAIL-transduced mice had significantly reduced blood glucose levels and markedly increased production of TIMP-1 compared with control β-galactosidase animals. Pancreatic tissue isolated from Ad.hTRAIL-treated NOD mice showed reduced MMP activities associated with significantly improved insulitis. In addition, TIMP-1 in vitro suppressed cytokine-induced apoptosis in insulin-producing INS-1 cells. These results indicate that T1D can be prevented by TRAIL overexpression through enhancement of TIMP-1 function. Elevated TIMP-1 production inhibits the activity of MMPs, which may contribute to suppress the transmigration of diabetogenic T cells into the pancreatic islets and protects pancreatic β-cells from cytokine-induced apoptosis. Therefore, TRAIL and TIMP-1 induction may be potential targets to prevent development of T1D.  相似文献   
993.
Jaceosidin (4′,5,7-trihydroxy–3′,6-dimethoxyflavone), isolated from Artemisia species as well as Eupatorium species, has antiallergic, anticancer, anti-inflammatory and antioxidant activity. A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC/MS/MS) method for the quantification of jaceosidin in rat plasma was developed to characterize the pharmacokinetics of jaceosidin. Jaceosidin and the internal standard, linezolid, were extracted from rat plasma with ethyl acetate at acidic pH and analyzed on a Luna phenyl-hexyl column using the mixture of acetonitrile and 0.1% formic acid (45:55, v/v) as a mobile phase. The analytes were determined using an electrospray ionization tandem mass spectrometry in the multiple-reaction-monitoring mode. The calibration curve was linear (r2 = 0.9973) over the concentration range of 2.00–500 ng/ml. The lower limit of quantification for jaceosidin was 2.0 ng/ml using 50 μl of plasma sample. The coefficients of variation of intra- and inter-assay at four QC levels were 2.4–9.6% and the relative errors were −9.1 to 10.0%. The matrix effects for jaceosidin and linezolid were practically absent. The recoveries of jaceosidin and linezolid were 87.0 and 87.7%, respectively. This method was successfully applied to the pharmacokinetic study of jaceosidin in rats.  相似文献   
994.
The dried roots of Sophora flavescens Aiton (SFA) has been used in traditional medicine for treatment of inflammation, gastrointestinal hemorrhage, diarrhea, and asthma. In the present study, we investigated the effect of SFA on the inflammatory allergic reaction using human mast cell-1 (HMC-1). SFA (200 mg/kg) inhibited the mast cell-mediated passive cutaneous anaphylaxis reaction in vivo and the release of histamine from rat peritoneal mast cells by compound 48/80. In addition, the expression levels of phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-stimulated TNF-α, IL-6, and IL-8 were also decreased by SFA treatment. In molecular mechanism level, this study showed that SFA inhibited the nuclear translocation of nuclear factor (NF) κB through inhibition of the phosphorylation and degradation of IκB-α, which is an inhibitor of NF κB. Moreover, SFA suppressed PMA plus A23187-induced phosphorylation of the mitogen-activated protein kinase p38 and c-jun N-terminal kinase. The inhibited induction of NF κB promoter by SFA was determined using luciferase activity. These results suggest that SFA could be used as a treatment for mast cell-derived allergic inflammatory diseases.  相似文献   
995.
Mast cells are responsible for IgE-mediated allergic responses. Although dietary flavonoid morin has been known to suppress mast cell activation, its in vivo anti-allergic activity and the underlying mechanisms remain are largely unknown. In this study, we determine whether morin suppresses IgE-mediated allergic responses in an animal model and its mechanism of action. Morin suppressed IgE-mediated PCA in mice (ED50 23.9 mg/kg) and inhibited degranulation and production of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-4 in antigen (Ag)-stimulated mast cells. The mechanism of action was a follows. Morin inhibited the activating phosphorylation of spleen tyrosine kinase (Syk) and linker for activation of T cells (LAT) in rat basophilic leukemia (RBL)-2H3 cells and bone marrow-derived mast cells (BMMCs). Akt and the mitogen-activated protein (MAP) kinases, p38, extracellular signal-regulated kinase (ERK)1/2, and c-Jun N-terminal kinase (JNK) were inhibited as well. In vitro kinase assay indicated that Fyn kinase, not Lyn and Syk, was inhibited by morin in a dose-dependent manner (IC50 5.7 μM). In conclusion, the results suggest that morin suppresses the IgE-mediated allergic response by primarily inhibiting Fyn kinase in mast cells.  相似文献   
996.
The mast cell-mediated immediate-type allergic reaction is involved in many allergic diseases such as asthma, allergic rhinitis, and sinusitis. Stimulation of mast cells starts the process of degranulation resulting in release of mediators such as histamine and an array of inflammatory cytokines. In this report, we investigated the effect of aqueous extract of Teucrium japonicum Houttuyn (Labiatae) (AXTJ) on the mast cell-mediated allergy model and studied its possible mechanisms of action. AXTJ inhibited compound 48/80-induced systemic reactions and serum histamine release in mice. AXTJ decreased immunoglobulin E-mediated passive cutaneous anaphylaxis reaction. AXTJ reduced histamine release and intracellular calcium from rat peritoneal mast cells activated by compound 48/80. In addition, AXTJ attenuated activation of nuclear factor (NF)-κB, and downstream tumor necrosis factor (TNF)-α expression in phorbol 12-myristate 13-acetate and calcium ionophore A23187-stimulated human mast cells. Our findings provide evidence that AXTJ inhibits mast cell-derived allergic reactions and involvement of intracellular calcium, TNF-α, and NF-κB in these effects.  相似文献   
997.
The increasing prevalence of strains of Plasmodium falciparum resistant to chloroquine and other antimalarial drugs, necessitates the need for developing novel antimalarial drugs with a potent pharmacological activity. Pyronaridine tetraphosphate (PNDP) is one such drug that is currently undergoing preclinical and clinical trials for use in a chemotherapy treatment of malaria. The present investigation was carried out with the objective of synthesizing carbon‐13 [13C]‐ and deuterium [2H]‐labeled PNDP for use in studying the ADME and pharmacokinetics of the drug. Here, we present a methodology to synthesize [13C]‐ and [2H]‐PNDP using a microwave irradiation technique as this method was found to be more advantageous than the classical method. The labeled compounds thus synthesized had a chemical purity of >99% as determined by HPLC and were also found to be relatively stable up to 3 months when stored under standard conditions. Further they also revealed satisfactory instrumental analysis data. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
998.
Age-related macular degeneration is the leading cause of blindness in the elderly. Choroidal neovascularization (CNV) leads to severe vision loss in patients of age-related macular degeneration. Previously, we have demonstrated that deguelin, isolated from plants in the Mundulea sericea family, is a chemopreventive agent. This study evaluates the antiangiogenic effect of deguelin on CNV. The toxicity of deguelin was evaluated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in human umbilical vein endothelial cells (HUVECs) as well as histological examination and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining in the deguelin-injected retina. Antiangiogenic activity of deguelin was evaluated by in vitro tube formation assay of HUVECs and in vivo angiogenesis of chick chorioallantoic membrane (CAM). In C57BL/6 mice with laser-induced CNV, deguelin or phosphate-buffered saline was injected intravitreously. CNV lesions were examined by fluorescence angiography and vessel counting in cross-sections. Deguelin showed no effect on cell viability of HUVECs and no retinal toxicity in a concentration range of 0.01 to 1 microM. Deguelin effectively inhibited in vitro tube formation of HUVECs and in vivo angiogenesis of CAM. Interestingly, deguelin significantly reduced CNV and its leakage in mouse model of laser photocoagulation-induced CNV. Our data suggests that deguelin is a potent inhibitor of CNV and may be applied in the treatment of other vasoproliferative retinopathies such as retinopathy of prematurity and diabetic retinopathy.  相似文献   
999.
1000.
Increasing condom use requires an understanding of the influencing factors. Previous research has used psychosocial theories such as the social cognitive theory and health belief to explain AIDS risk factors and condom use. However, it is still difficult to effectively predict the multidimensional factors associated with condom use. The present study utilizes the transtheoretical model to investigate condom use among college students by examining stages of change for condom use and measuring decisional balance and self-efficacy for each stage. The aim was to identify the variables affecting condom use so as to provide scientific data that would aid the development of effective strategies for increasing condom use.  相似文献   
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