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991.

Aim of study

This study was performed to elicit the effectiveness of bee venom (BV), a traditional immunosuppressive Korean acupuncture agent, on the maturation of dendrtic cells (DCs).

Materials and methods

Immature dendritic cells (iDCs) were generated from mouse bone marrow cells with GM-CSF. After 10 days of initial differentiation, DCs were activated with lipopolysaccharides (LPS) for another 48h in the presence or absence of BV. Surface molecule analysis, intracytoplasmic staining of cytokines, FITC-conjugated antigen uptake, and transwell migration assays were conducted with iDCs and activated DCs.

Results

Up-regulation of costimulatory molecules, typical of mature DCs (mDCs) was inhibited by addition of BV. Pro-inflammatory cytokines were also found to be reduced with BV treatment in LPS-stimulated DC. A decrease in antigen uptake upon the maturation of DC was reversed in low dose BV treated mDC. In addition, BV treated mDC demonstrated reduced directional migration in response to CCL21, a lymphoid chemokine which directs mDC.

Conclusions

BV may have a therapeutic effect an on abnormally activated immune status, such as autoimmune rheumatoid arthritis, through an immune-modulatory effect on DC.  相似文献   
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Dietary interventions may have the potential to counter age-related cognitive decline. Studies have demonstrated an improvement in age-related cognitive impairment in animals after supplementation with plant extracts containing flavonoids but there are few human studies. This double-blind, controlled study examined the effects on cognitive performance of a 5 week supplementation with Enzogenol Pinus radiata bark extract containing flavonoids, in 42 males aged 50-65 years, with a body mass index >25. Participants were supplemented for 5 weeks either with Enzogenol plus vitamin C, or with vitamin C only. A battery of computerized cognitive tests was administered, and cardiovascular and haematological parameters were assessed prior to and following supplementation. The speed of response for the spatial working memory and immediate recognition tasks improved after supplementation with Enzogenol plus vitamin C, whereas vitamin C alone showed no improvements. A trend in a reduction of systolic blood pressure was observed with Enzogenol plus vitamin C, but not with vitamin C alone. The blood safety parameters were unchanged. The findings suggest a beneficial effect of supplementation with Enzogenol on cognition in older individuals. Larger studies are needed to ascertain its potential as a preventive treatment for age-related cognitive decline.  相似文献   
994.
In early dental plaque formation, oral primary colonizers such as Streptococcus mutans, Streptococcus sanguis and Actinomyces viscosus are initially attached to the pellicle-coated tooth surface to form a biofilm. The study aimed to determine the efficacy of macelignan, isolated from nutmeg (Myristica fragrans Houtt.), in removing each single oral primary biofilm in vitro on a polystyrene 96-well microtiter plate. Four biofilm growth phases (4, 12, 20 and 24 h) were evaluated in this study after treatment with macelignan at various concentrations (0.2, 2 and 10 microg/mL) and exposure times (5, 10 and 30 min). Anti-biofilm activity of macelignan was measured as the percentage of the remaining biofilm absorbance after macelignan treatment in comparison with the untreated control. At 24 h of biofilm growth, S. mutans, A. viscosus and S. sanguis biofilms were reduced by up to 30%, 30% and 38%, respectively, after treatment with 10 microg/mL macelignan for 5 min. Increasing the treatment time to 30 min resulted in a reduction of more than 50% of each of the single primary biofilms. The results indicate that macelignan is a potent natural anti-biofilm agent against oral primary colonizers.  相似文献   
995.
Placenta-restricted expression of LTR-derived NOS3   总被引:2,自引:0,他引:2  
Huh JW  Ha HS  Kim DS  Kim HS 《Placenta》2008,29(7):602-608
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996.
OBJECTIVES: To estimate the combined screening performance of first and early second trimester prenatal serum markers for Down syndrome, in screening for the development of preeclampsia, and analyze the correlation among marker levels, week of onset, and severity of the disease. METHODS: A retrospective cohort study was carried out on 32 women with preeclampsia and 3044 controls. Serum samples from these pregnancies were assayed for pregnancy-associated plasma protein-A (PAPP-A), alpha-fetoprotein (AFP), unconjugated estriol (uE3), human chorionic gonadotrophin (hCG), and inhibin-A. A likelihood ratio and the odds of being affected given a positive result (OAPR) of various combinations of markers were calculated and receiver operating characteristic (ROC) curves analysis was performed. RESULTS: In the pregnancies that subsequently developed preeclampsia, first trimester PAPP-A concentration was significantly lower and concentrations of early second trimester inhibin-A and hCG significantly elevated. Levels of early second trimester uE3 and AFP were not significantly altered. We also found that inhibin-A correlates with both onset of the disease and the severity. CONCLUSION: Down syndrome biochemical markers levels are altered in those patients who subsequently developed preeclampsia and may be a useful screening test for preeclampsia. Inhibin-A is the most predictive marker and correlates with the severity of subsequent preeclampsia and inversely with the week of occurrence of preeclampsia.  相似文献   
997.
OBJECTIVE: The objective was to determine the direct effect of letrozole on the proliferation and apoptosis of cultured leiomyoma cells co-treated with prostaglandin E(2) (PGE(2)). STUDY DESIGN: Leiomyoma cells were obtained from three groups of patients who had undergone hysterectomy due to leiomyoma. Percentages of antiproliferative cells were evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and apoptosis was assessed with sub-G1 cell counts by flow cytometry and Western blot analysis. RESULTS: Combined treatment with 100 microM letrozole and 10 microM PGE(2) for 48 h resulted in a significantly lower viability rate (25.9+/-4.5%) and an increased cell death rate (31.6+/-4.4%) than groups treated with letrozole or PGE(2) alone. However, after adding 10nM estradiol to the combined treatment group, the cell viability rate was restored (75.1+/-7.7%) and the cell death rate was decreased (10.5+/-3.1%). Increased caspase-3 expression was found in the letrozole and PGE(2) combined treatment group, but not in the group in which estradiol was added. CONCLUSION: The present results demonstrate that letrozole inhibits growth and induces apoptosis of leiomyoma cells by blocking the aromatase up-regulated by PGE(2) treatment. These findings support the need for further investigation of aromatase inhibitors as a medical treatment option in leiomyoma.  相似文献   
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