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31.
32.

Aim:

To investigate the effects of piperlongumine (PL), an anticancer alkaloid from long pepper plants, on the primary myeloid leukemia cells from patients and the mechanisms of action.

Methods:

Human BM samples were obtained from 9 patients with acute or chronic myeloid leukemias and 2 patients with myelodysplastic syndrome (MDS). Bone marrow mononuclear cells (BMMNCs) were isolated and cultured. Cell viability was determined using MTT assay, and apoptosis was examined with PI staining or flow cytometry. ROS levels in the cells were determined using DCFH-DA staining and flow cytometry. Expression of apoptotic and autophagic signaling proteins was analyzed using Western blotting.

Results:

PL inhibited the viability of BMMNCs from the patients with myeloid leukemias (with IC50 less than 20 μmol/L), but not that of BMMNCs from a patient with MDS. Furthermore, PL (10 and 20 μmol/L) induced apoptosis of BMMNCs from the patients with myeloid leukemias in a dose-dependent manner. PL markedly increased ROS levels in BMMNCs from the patients with myeloid leukemias, whereas pretreatment with the antioxidant N-acetyl-L-cysteine abolished PL-induced ROS accumulation and effectively reduced PL-induced cytotoxicity. Moreover, PL markedly increased the expression of the apoptotic proteins (Bax, Bcl-2 and caspase-3) and autophagic proteins (Beclin-1 and LC3B), and phosphorylation of p38 and JNK in BMMNCs from the patients with myeloid leukemias, whereas pretreatment with the specific p38 inhibitor SB203580 or the specific JNK inhibitor SP600125 partially reversed PL-induced ROS production, apoptotic/autophagic signaling activation and cytotoxicity.

Conclusion:

Piperlongumine induces apoptotic and autophagic death of the primary myeloid leukemia cells from patients via activation of ROS-p38/JNK pathways.  相似文献   
33.
Previous studies have shown that the effects of manual acupuncture (MA) are contributed by collagen fibers and mast cells in local acupoints, at which acupuncture stimulation causes various afferent fiber groups to be excited. However what happens in local nerve fibers and mast cells after MA remains unclear. The aim of this study was to examine the response of cutaneous nerve fibers and mast cells to MA stimulation in acupoint Hegu (LI4). The contralateral LI4 of the same rat was used as a non-stimulated control. Immnohistochemistry analysis were carried out to observe the expression of histamine (HA), serotonin (5-HT) and nociceptive neuropeptides, calcitonin gene-related peptide (CGRP) and substance P (SP), in the LI4 area. Mast cells were labeled with anti-mast cell tryptase antibody and simultaneously with HA or 5-HT primary antibodies to observe their co-expression. Our results showed that SP and CGRP were expressed more highly on the cutaneous nerve fibers of LI4 after MA stimulation than that of the control. Mast cells aggregated in close proximity to the blood vessels in intra-epidermis and dermis and some of them with degranulation in the lower dermis and subcutaneous tissue of LI4. Both mast cells and their granules appeared with HA (+) and 5-HT (+) expression at stimulated L14 sites, while a few intact mast cells with a little expression of 5-HT and HA were distributed in areas of non-stimulated L14. The results indicated that local cutaneous nerve terminals and mast cells responded to MA with higher expression of SP and CGRP in nerve fibers, as well as with aggregation and degranulation of mast cells with HA and 5-HT granules at acupoint LI4. These neuroactive substances may convey signals to certain pathways that contribute to the effects of acupuncture.  相似文献   
34.
目的:观察电针神门、三阴交对失眠症患者焦虑、抑郁状态的影响,并探索其配伍效应的作用机制。方法:将90例失眠症患者随机分为配伍组、神门组和三阴交组,每组30例,并进一步筛选出37例焦虑状态患者(配伍组12例、神门组13例、三阴交组12例)和42例抑郁状态患者(配伍组14例、神门组14例、三阴交组14例)。配伍组、神门组、三阴交组分别予电针神门-三阴交、神门单穴及三阴交单穴,疏密波,频率5 Hz/25 Hz,治疗每次30 min,每天1次,连续治疗5 d为一疗程,共治疗2个疗程。分别于治疗前后评定各组患者失眠严重程度指数(ISI)、焦虑自评量表(SAS)和抑郁自评量表(SDS)评分,检测血清多巴胺(DA)和去甲肾上腺素(NE)含量。结果:与治疗前比较,治疗后3组患者ISI、SAS、SDS评分均降低(P<0.05),配伍组ISI评分低于神门组(P<0.05)。治疗后,3组失眠症焦虑状态患者ISI、SAS评分及血清DA含量均较治疗前下降(P<0.05),配伍组、神门组患者血清NE较治疗前下降(P<0.05);配伍组、神门组患者SAS评分、血清NE含量及配伍组ISI评分低...  相似文献   
35.
白芍总甙对豚鼠结肠平滑肌作用机制的研究   总被引:8,自引:3,他引:8  
目的 :探讨白芍总甙 (TGP)对离体豚鼠结肠平滑肌的作用方式及对结肠平滑肌中 P物质 (SP)和血管活性肠肽 (VIP)释放的影响。方法 :观察不同剂量 TGP及工具药对离体结肠肌收缩活性的效应及利用 SABC法检测结肠平滑肌中 SP和血管 VIP的变化。结果 :TGP使豚鼠结肠离体平滑肌收缩积分和时间显著性增加 ,且收缩效应的改变具有剂量依赖性。平滑肌中 SP的反应显著性增强。结论 :TGP可通过延长结肠收缩时间 ,增强结肠收缩幅度而调节结肠运动 ,SP是 TGP作用的递质之一。  相似文献   
36.
37.

Background

Hormone replacement therapy may be beneficial for cardiovascular disease risk (CVR) in post-menopausal women. Soy isoflavones may act as selective estrogen receptor modulators. The aim of this study was to evaluate whether soy isoflavones had an effect on CVR markers.

Methods

The expected 10-year risk of cardiovascular disease and mortality were calculated as a secondary endpoint from a double blind randomised parallel study involving 200 women (mean age 55 years, Caucasian, Hull, UK, 2012) in the early menopause who were randomised to 15 g soy protein with 66 mg isoflavone (SPI) or 15 g soy protein alone (depleted of all isoflavones; SP) given as a snack bar between meals daily for 6 months. Age, diabetes, smoking, blood pressure and lipid profiles were used to calculate CVR using the Framingham CVR engine.

Results

SPI treatment resulted in a significant reduction in the metabolic parameters and systolic blood pressure compared to SP (p < 0.01). There were no changes in fasting lipid profile and diastolic blood pressure with either treatment. At 6 months, changes in these parameters with SPI treatment were reflected in a calculated 27% (p < 0.01) reduction in 10 year coronary heart disease risk, a 37% (p < 0.01) reduction in myocardial infarction risk, a 24% (p < 0.04) reduction in cardiovascular disease and 42% (p < 0.02) reduction in cardiovascular disease death risk.

Conclusions

Supplementation with soy protein with isoflavones for 6 months significantly improved CVR markers and calculated CVR at 6 months during early menopause compared to soy protein without isoflavones.

ISRCTN registry

ISRCTN34051237.  相似文献   
38.
39.
Cancer stem cells (CSCs) comprise a tumor subpopulation responsible for tumor maintenance, resistance to chemotherapy, recurrence and metastasis. The identification of this cell group is very important, but there is still no consensus on its characterization. Several CSC markers have been described, like CD133, CD24, CD44 and ALDH1, but more research to identify new markers to facilitate the identification of CSC in a heterogeneous tumoral mass is required. Thus, this article describes the CD26 expression as a CSC marker and the role that it plays in different types of cancer. CD26 expression correlates with some characteristics of CSCs, like the formation of spheres in vitro, formation of new tumors, and resistance to chemotherapy. CD26 is therefore suggested as an auxiliary marker for CSC in different types of cancer, and as a potential therapeutic target.  相似文献   
40.
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