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51.
52.
鹅掌藤中三萜类化合物的分离与鉴定 总被引:11,自引:2,他引:11
目的研究五加科鹅掌柴属植物鹅掌藤(Schefflera arboricola)枝茎的化学成分.方法采用柱色谱分离,通过理化数据和光谱分析确定化合物的结构.结果从鹅掌藤乙酸乙酯提取物中分离得到7个三萜化合物,分别鉴定为羽扇醇(1)、桦木酸(2)、3-epi-betulinic acid(3)、齐墩果酸(4)、3-乙酰齐墩果酸(5)、mesembryanthemoidigenic acid(6)、quinatic acid(7).结论化合物1、5、6、7为首次从该属植物中分得. 相似文献
53.
Gatifloxacin inducing apoptosis of stromal fibroblasts through cross-talk between caspase-dependent extrinsic and intrinsic pathways 下载免费PDF全文
AIM: To reveal the cytotoxicity and related mechanisms of gatifloxacin (GFX) to stromal fibroblasts (SFs) in vitro.
METHODS: SFs were treated with GFX at different concentrations (0.009375%-0.3%), and their viability was detected by MTT method. The cell morphology was observed using light/transmission electron microscope. The plasma membrane permeability was measured by AO/EB double-staining. Then cell cycle, phosphatidylserine (PS) externalization, and mitochondrial transmembrane potential (MTP) were analyzed by flow cytometry. DNA damage was analyzed by electrophoresis and immunostaining. ELISA was used to evaluate the caspase-3/-8/-9 activation. Finally, Western blotting was applied for detecting the expressions of apoptosis-related proteins.
RESULTS: Morphological changes and reduced viability of GFX-treated SFs demonstrated that GFX above 0.009375% had cytotoxicity to SFs with dependence of concentration and time. GFX-treating cells also showed G1 phase arrest, increased membrane permeability, PS externalization and DNA damage, which indicated that GFX induced apoptosis of SFs. Additionally, GFX could activate the caspase-8, caspase-9, and caspase-3, induce MTP disruption, downregulate B-cell leukemia-2 (Bcl-2) and B-cell leukemia-XL (Bcl-XL), and upregulate Bcl-2 assaciated X protein (Bax), Bcl-2-associated death promoter (Bad), Bcl-2 interacting domain (Bid) and cytoplasmic cytochrome C in SFs, suggesting that caspase-dependent extrinsic and intrinsic pathways were related to GFX-contributed apoptosis of SFs.
CONCLUSION: The cytotoxicity of GFX induces apoptosis of SFs through triggering the caspase-dependent extrinsic and intrinsic pathways. 相似文献
54.
目的:探讨转染解聚素-金属蛋白酶17-shRNA(a disintegrin and metalloprotease 17-shRNA,ADAM 17-shRNA)的骨髓间充质干细胞(bone marrow mesenehymal stem cells,BMMSC)对乳腺癌MCF-7细胞裸鼠移植瘤的抑制效果.方法:全骨髓贴壁法分离并培养3周雄性SD大鼠的BMMSC,利用慢病毒介导的ADAM17-shRNA转染BMMSC.30只裸鼠建立MCF-7乳腺癌移植瘤模型,种植肿瘤细胞14d后建模成功.按照数字表法随机分成对照组(注射等量PBS)、BMMSC组(注射l×106/mlBMMSC)和转染组(注射1×106/ml转染ADAM 17-shRNA的BMMSC),每组10只.在种植细胞第15天开始经尾静脉注射BMMSC进行抑瘤实验(0.1 ml/只,每3d给药1次,共计5次),观察裸小鼠移植瘤的生长情况;抑瘤实验16d后处死裸鼠.利用Real-time PCR法检测移植瘤组织ADAM17 mRNA表达,Westem blotting法检测移植瘤组织ADAM 17蛋白表达.结果:抑瘤实验16d时,对照组、BMMSC组移植瘤体积明显高于转染组[(787.15±25.95)、(767.02±28.98) vs (361.89±19.75)mm3,均P<0.01];BMMSC组、转染组抑瘤率明显高于对照组(2.57%、53.89% vs 0.00%,均P<0.05).对照组、BMMSC组ADAM17 mRNA的表达水平明显高于转染组(1.00±0.01、0.97±0.08 vs 0.30±0.09,均P<0.05);对照组、BMMSC组ADAM 17蛋白表达水平明显高于转染组(0.70±0.09、0.68±0.02 vs 0.45±0.05,均P<0.05).结论:ADAM 17-shRNA通过BMMSC介导可将ADAM17靶向归巢至裸鼠乳腺癌移植瘤并发挥抑瘤作用. 相似文献
55.
“保胎Ⅰ冲剂”提高反复自然流产患者免疫功能的临床观察 总被引:2,自引:0,他引:2
为探讨中药对反复自然流产患者的免疫调节作用 ,用自制“保胎Ⅰ冲剂”治疗反复自然流产患者 3 6例 ,观察治疗前后患者血清中封闭抗体对配偶外周血T淋巴细胞CD3 、CD4及CD8抗原反应的变化。结果 :治疗后抗CD3 、抗CD8明显升高 ,抗CD4/CD8下降 ;妊娠成功率 91 67%。提示中药对母胎免疫有调节作用 ,且作用安全 相似文献
56.
目的:构建慢病毒干扰LSD1表达的载体并鉴定。方法:设计并合成3对针对LSD1基因的shRNA链,退火形成双链,与酶切的质粒连接,转化DH5a菌株,提取质粒,进行酶切鉴定和测序分析。脂质体法转染人胃癌MKN-28细胞,通过荧光倒置显微镜判定转染效率,并通过real time-PCR法检测细胞中LSD1基因的表达水平。结果:经酶切鉴定筛选出的重组质粒测序结果与目的序列相同,重组质粒构建成功;转染胃癌MKN-28细胞后,LSD1基因在mRNA水平的表达降低。结论:成功构建了靶向LSD1基因的shRNA慢病毒载体,并筛选出1种对LSD1基因有显著抑制作用的shRNA。 相似文献
57.
58.
目的了解本地区健康人群血尿酸浓度,及正常人群存在的无症状性高、低尿酸血症群体比例。方法用尿酸氧化酶法,检测了624份健康人血清样品。结果男性<10岁为163.2±50.0umol/L,11~20岁为253.2±65.3umol/L,中青年(21~50)为232.5±73.2umol/L,>51岁组为231.6±69.3umol/L。女性<10岁组为140.6±49.7umol/L,11~20岁组为174.3±62.2umol/L,中青年(21~50)为177.0±58.1umol/L,>51岁组为214.4±69.4umol/L。同年龄段男女间比较:在<10岁,无显著性差异(p>0.05);在11~50岁,相差均非常显著(p<0.001);从51岁以后,差异无显著性(p>0.05)。男性UA在l~10组水平较低,与其它组比较,差异显著(P<0.001),11~20组与41~50、51~60组相比差异显著(p<0.05)。女性UA在1~10年龄段水平较低,与其它组比较,差异显著(P<0.001),31~40水平最低,41岁以后呈增高趋势。61岁以后比50岁以前水平增高,差异有显著性(p<0.05)。结论诊断高、低尿酸血症各地区最好建立自己的血清尿酸参考范围。 相似文献
59.
Xiaoning Guo Xiaohui Wang Sui Shen Bryan Oronsky Tony R Reid Meaghan Stirn Scott Caroen Franck Brinkhaus Nacer A Abrouk Liandai Yang Lianzong Wu Zhongwen Yu 《American journal of cancer research》2022,12(9):4448
RRx-001, a CD47 antagonist via its inhibition of MYC and the γ-subtype of the peroxisome proliferator-activated receptor (PPAR) has been associated to date with minimal toxicity. The aim of this post-hoc analysis was to evaluate the toxicity and efficacy of RRx-001 in Asian patients since RRx-001, in the context of multiple Phase 3 studies, will be administered in China and Chinese territories as well as potentially throughout the rest of Asia. Patients received 4 mg of RRx-001 in three different antitumor clinical trials with chemotherapy and/or radiation and a retrospective subset efficacy and toxicity analysis was conducted for patients with Asian ancestry in comparison to patients with other ethnic backgrounds. The toxicity and efficacy data from these studies were similar between Asians and the rest of the treated patients. While the sample sizes are too small to draw definitive conclusions, at a dose of 4 mg, when RRx-001 is combined with chemotherapy, no apparent differences in terms of safety and efficacy are observed in cancer patients with Asian ancestry. 相似文献
60.
Zhongquan Dai Hongyu Zhang Feng Wu Ying Chen Chao Yang Hailong Wang Xiukun Sui Yaxiu Guo Bingmu Xin Zhifeng Guo Jianghui Xiong Bin Wu Yinghui Li 《Nutrients》2022,14(18)
Fasting shows great potential in preventing chronic diseases and has to be surmounted under some extraordinary circumstances. This study aimed to investigate the safety, time effects of metabolic homeostasis and health indexes during prolonged fasting. Thirteen participants were recruited to conduct a 10-day complete fasting (CF) in a controlled health research building under medical supervision including 3-day Baseline (BL), 10-day CF, 4-day calorie restriction (CR) and 5-day full recovery (FR). Body healthy status was assessed by surveying pulse, blood pressure, body weight (BW), blood glucose and ketones, body composition and nutritional and biochemistry indexes at different times. BW declined about 7.28 kg (−9.8%) after 10-day CF, accompanied by increased pulse and decreased systolic blood pressure, but there were no changes to the myocardial enzymogram. Body composition analysis showed fat mass was constantly lost, but lean mass could recover after CR. The energy substrate switch from glucose to ketone occurred and formed a stable dynamic balance between 3–6 days of CF. The lipid metabolism presented increased total cholesterol, LDL-C, ApoA1 and almost no changes to TG and HDL-C. Prolonged CF did not influence liver function, but induced a slight decrease of kidney function. The interesting results came from the marked increase of lipid-soluble vitamins and a significant decrease of sodium and chlorine. Adults could well tol-erate a 10-day CF. A new metabolic homeostasis was achieved. No vitamins but NaCl supplement should be considered. These findings provide evidence to design a new fasting strategy for clinical practice. 相似文献