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为了寻找毒性低、增敏作用强的乏氧细胞放射增敏剂,设计并合成了一系列5-溴-,5-甲基-,和5-未取代的3-硝基-1,2,4-三唑-1-乙酰胺类化合物,用HeLaS3细胞进行了体外试验。结果表明5-溴取代衍生物的增敏作用强于相应的5-甲基-或5-未取代的硝基三唑衍生物,但是它们的毒性亦增大。修饰1位乙酰胺侧链也可以改变化合物的增敏作用和亲脂性。在所测定的化合物中TA-101[2-(3-硝基-1-三唑基)乙酰胺]由于有高的增敏作用和低亲脂性,可能是一个有希望的放射增敏剂。  相似文献   
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The oncogenic PI3K/Akt/mammalian target of rapamycin (mTOR) signaling axis and its downstream effector, the ribosomal protein S6 kinase 1 (S6K1) play a key role in mediating cell survival in various tumor cells. Here, we investigated the effects of brassinin (BSN), a phytoalexin first identified as a constituent of cabbage, on the PI3K/Akt/mTOR/S6K1 activation, cellular proliferation, and apoptosis in PC‐3 human prostate cancer. BSN exerted a significant dose‐dependent cytotoxicity and reduced constitutive phosphorylation of Akt against androgen‐independent PC‐3 cells as compared to androgen‐dependent LNCaP cells. Moreover, knockdown of androgen receptor (AR) by small interfering RNA enhanced the potential effect of BSN on induction of apoptosis in LNCaP cells. BSN clearly suppressed the constitutive activation of PI3K/Akt/mTOR/S6K1 signaling cascade, which correlated with the induction of apoptosis as characterized by accumulation of cells in subG1 phase, positive Annexin V binding, TUNEL staining, loss of mitochondrial membrane potential, down‐regulation of antiapoptotic and proliferative proteins, activation of caspase‐3, and cleavage of PARP. Additionally, BSN could block broad‐spectrum inhibition of PI3K/Akt/mTOR/S6K1 axes, and aberrant Akt activation by pcDNA3‐myr‐HA‐Akt1 plasmid could not prevent the observed suppressive effect of BSN on constitutive mTOR activation. Finally, overexpression of Bcl‐2 also attenuated BSN‐mediated apoptosis in PC‐3 cells. Taken together, our findings suggest that BSN can interfere with multiple signaling cascades involved in tumorigenesis and might be provided as a potential therapeutic candidate for both the prevention and treatment of prostate cancer. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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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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Obesity and overweight are closely related to diet, and the gut microbiota play an important role in body weight and human health. The aim of this study was to explore how Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032 supplementation alleviate obesity by modulating the human gut microbiome. A randomized, double-blind, placebo-controlled study was conducted on 72 individuals with overweight. Over a 12-week period, probiotic groups consumed 1 × 1010 colony-forming units of HY7601 and KY1032, whereas the placebo group consumed the same product without probiotics. After treatment, the probiotic group displayed a reduction in body weight (p < 0.001), visceral fat mass (p < 0.025), and waist circumference (p < 0.007), and an increase in adiponectin (p < 0.046), compared with the placebo group. Additionally, HY7601 and KY1032 supplementation modulated bacterial gut microbiota characteristics and beta diversity by increasing Bifidobacteriaceae and Akkermansiaceae and decreasing Prevotellaceae and Selenomonadaceae. In summary, HY7601 and KY1032 probiotics exert anti-obesity effects by regulating the gut microbiota; hence, they have therapeutic potential for preventing or alleviating obesity and living with overweight.  相似文献   
38.
PurposeInterleukin (IL)-17A has been suggested to play a role in the growth and organization of thrombi. We examined whether IL-17A plays a role in the early stages of thrombosis and whether there are sex differences in the effects of IL-17A.Materials and MethodsWe performed a blinded, randomized, placebo-controlled study to compare time to thrombotic occlusion and sex differences therein between mice treated with IL-17A and those treated with saline using a ferric chloride-induced model. We also assessed thrombus histology, blood coagulation, and plasma levels of coagulation factors.ResultsTime to occlusion values did not differ between the IL-17A group and the control group (94.6±86.9 sec vs. 121.0±84.4 sec, p=0.238). However, it was significantly shorter in the IL-17A group of female mice (74.6±57.2 sec vs. 130.0±76.2 sec, p=0.032). In rotational thromboelastometry, the IL-17A group exhibited increased maximum clot firmness (71.3±4.5 mm vs. 66.7±4.7 mm, p=0.038) and greater amplitude at 30 min (69.7±5.2 mm vs. 64.5±5.3 mm, p=0.040) than the control group. In Western blotting, the IL-17A group showed higher levels of coagulation factor XIII (2.2±1.5 vs. 1.0±0.9, p=0.008), monocyte chemoattractant protein-1 (1.6±0.6 vs. 1.0±0.4, p=0.023), and tissue factor (1.5±0.6 vs. 1.0±0.5, p=0.003).ConclusionIL-17A plays a role in the initial st ages of arterial thrombosis in mice. Coagulation factors and monocyte chemoattractant protein-1 may be associated with IL-17A-mediated thrombosis.  相似文献   
39.
PurposeThis study aimed to evaluate the cumulative recurrence rate and risk factors for recurrent abdominal wall endometriosis (AWE) after surgical treatment.Materials and MethodsA retrospective cohort study was conducted at a single gynecological surgery center between January 2004 and December 2020. Patients who were surgically treated and followed up for at least 6 months after surgery were selected.ResultsEighteen patients with pathologically diagnosed AWE were included in this study. The median follow-up duration was 22.5 months (range, 6–106). The median age was 37 years (range, 22–48), and 33.3% of the patients were nulliparous. Among the patients included in our study, 55.6% complained of a mass with cyclic pain, and 27.8% had a palpable mass. In addition, 22.2% of patients experienced recurrence with 17.5±9.7 months of mean time to recurrence. The cumulative recurrence rates at 24 and 60 months after surgical treatment of AWE were 23.8% and 39.1%, respectively. There were no statistically significant risk factors for the recurrence of AWE, including postoperative medical treatment.ConclusionThe recurrence rate of AWE appears to be correlated with the follow-up duration. There was no statistically significant risk factor for the recurrence of AWE. Unlike ovarian endometriosis, postoperative hormonal treatment does not seem to lower the recurrence of AWE. The findings of the current study may help healthcare providers in counselling and managing patients with AWE.  相似文献   
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