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21.
血管内皮生长因子促进小鼠胚胎干细胞的造血分化   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:研究血管内皮生长因子(VEGF)体外促进小鼠胚胎干细胞系ES-D3向造血分化的能力。方法:先将ES-D3形成拟胚体,将拟胚体细胞转入含不同浓度的VEGF和VEGF+SCF的培养基中。实验分6组,分别为VEGF 5 μg/L组、VEGF 10 μg/L组、VEGF 20 μg/L组、VEGF 5 μg/L+SCF组、VEGF 10 μg/L+SCF组、VEGF 20 μg/L+SCF组,同时设不加因子的自发分化对照组。RT-PCR检测造血转录基因GATA-2和早期造血细胞基因c-kit和β-H1的表达,流式细胞仪检测CD34+细胞,甲基纤维素半固体培养法检测生成造血集落的能力。结果:经过1周的诱导培养,实验组生成的细胞可以表达GATA-2、c-kit和β-H1,CD34+细胞的比例也升高,并可形成造血祖细胞的集落。从诱导生成CD34+细胞的比例和生成的集落数量看,VEGF联合SCF组的诱导效率要高于VEGF单用组和对照组,其中以VEGF 20 μg/L+SCF组和VEGF 10 μg/L+SCF组的诱导效率最高。结论:VEGF能够促进ESC的早期造血分化,尤以与SCF合用时,其诱导效率更高。  相似文献   
22.
CpG-ODN诱导白血病HL60细胞分化和凋亡的研究   总被引:2,自引:1,他引:2       下载免费PDF全文
目的:研究含CpG基序的寡核苷酸对白血病HL60细胞的作用。方法:设计合成含CpG基序的寡核苷酸(CpG-ODN)、不含CpG基序的寡核苷酸(nonCpG-ODN)和含甲基化CpG基序的寡核苷酸(ZpG-ODN)分别作用于白血病HL60细胞,MTT法测定HL60细胞抑制效应,硝基四氮唑蓝还原实验和细胞表面CD14分子表达状况分析HL60细胞诱导分化结果,流式细胞仪和透射电镜观察HL60细胞的凋亡现象,免疫组化检测HL60细胞后caspase3、Bcl-2和Bax的表达状况。结果:CpG-ODN对白血病HL60细胞有诱导分化和诱导凋亡作用,nonCpG-ODN和ZpG-ODN无此作用。结论:CpG-ODN可直接诱导白血病HL60细胞分化和凋亡,此为白血病免疫治疗提供了新的途径。  相似文献   
23.
目的:研究选择性雌激素受体调节剂(SERM)雷洛昔芬(raloxifene)对血管内皮细胞雌激素应答元件(ERE)转录活性的影响。方法:首先构建ERE荧光素酶报告基因质粒(ERE-TK-Luc),然后采用真核细胞转染技术将ERE-TK-Luc与内参照质粒PRL-SV40一起转染体外培养的血管内皮细胞,检测raloxifene刺激的转染细胞荧光素酶的相对活性,与未用药的转染细胞进行比较。并同时采用raloxifene与雌二醇(E2)共同处理细胞,观察raloxifene对E2作用的影响。结果:在raloxifene处理的转染细胞中荧光素酶表达量低于未用药的转染细胞,raloxifene浓度为10-7mol/L时更明显(P<0.01);E2可使转染细胞荧光素酶表达量明显高于未给药组(P<0.01),而raloxifene与E2同时处理则细胞荧光素酶表达水平与对照组相近(P<0.01)。结论:Raloxifene对血管内皮细胞ERE转录活性有抑制作用。  相似文献   
24.
《世界针灸杂志》2023,33(3):213-221
ObjectiveTo observe the effects of electroacupuncture (EA) with varied frequencies on headache and anxiety-depression symptoms in patients with migraine and to screen optimal frequency of EA for patients with such conditions.DesignSingle-center, randomized, controlled clinical trial was designed, and the outcome assessors and statisticians were blinded. The patients with migraine were randomized into 2 Hz EA group, 100 Hz EA group and sham-stimulation group. In each group, the changes in migraine attacks, days with headache, the scores of visual analogy scale (VAS), self-rating anxiety scale (SAS), self-rating depression scale (SDS) and migraine-specific quality-of-life questionnaire (MSQ), as well as the dosage of analgesics were observed at the baseline, during treatment, in 1, 2 and 3 months of follow-up separately.SettingPatients were enrolled in the Third Affiliated Hospital of Zhejiang Chinese Medical University, between 1st August 2018 and 31st July 2021.ParticipantsSixty-five migraine patients with or without aura.InterventionsIn the EA groups, the acupoints were bilateral Fengchi (GB20), Gongxue (Extra), Sizhukong (TE23), Taiyang (EX-HN5), Shuaigu (GB8), Waiguan (TE5) and Yanglingquan (GB34). Electric stimulation was exerted at GB20 and Gongxue (Extra), with 2 Hz and 100 Hz separately. In the sham-stimulation group, the shallow acupuncture was operated at the sites 1 cm lateral to GB20 and Gongxue (Extra), and on the radial side of TE5 and GB34. The output wires were cut off after attached to the acupoints. The patients in each group received the treatment 3 times weekly, once every two days, for consecutive 4 weeks. The complete intervention was composed of 12 treatments.Main outcome measuresChanges in numbers of migraine attacks at treatment phase (week 1 to week 4) from the baseline(week -4 to week 0) in patients of each groupResults(1) Changes in migraine attacks and days with headache: In the 2 Hz EA and 100 Hz EA groups, the changes for migraine attacks and days of headache were higher significantly when compared with that in the sham-stimulation group at the same time stage (P < 0.05). There was no statistical difference between two EA groups. (2) Changes of VAS score: In the 2 Hz EA and 100 Hz EA groups, the changes of VAS score were significantly higher when compared with that in the sham-stimulation group at the same time stage (P < 0.05). There was no statistical difference between two EA groups. (3) Assessment of anxiety and depression: The differences in the changes of SAS and SDS scores had no statistical significance in patients of each group at each assessment stage (P > 0.05). (4) Assessment on the quality of life: Compared with the sham-stimulation group at the same time stage, the improvement in MSQ score was increased significantly during treatment in patients of the 2 Hz EA and 100 Hz groups (P < 0.05). There was no statistical difference between two EA groups. (5) Assessment on safety and compliance: The patients of each group had sound compliance. There was no adverse events during trial, suggesting promising safety of treatment.ConclusionEA may effectively reduce the migraine attacks, and the days and intensity of headache, presenting promising safety. However, there was no significant improvement on anxiety-depression symptoms, and no significant difference between high and low frequencies of EA treatment in relieving headache and anxiety/depression symptoms in the patients with migraine.Trial registrationChiCTR1800017259  相似文献   
25.
ObjectiveTo analyze the clinical characteristics and controllable risk factors of osteoporosis in elderly men with type‐2 diabetes mellitus (T2DM).MethodsA total of 250 elderly OP patients with T2DM were included in the present study. Patients with one or more common chronic diseases (including hypertension, coronary heart disease, heart failure, chronic bronchitis, chronic nephrosis, and cirrhosis), and a course of more than 3 years were defined as complicated with chronic diseases. Blood glucose, cholesterol, triglyceride, low‐density lipoprotein, high‐density lipoprotein, calcium, phosphorus, glycosylated hemoglobin, urea nitrogen, creatinine, fasting insulin, liver function, and 25‐hydroxy vitamin D3 levels were measured. Bone mineral density was also measured.ResultsA total of 16 patients (6.4%) had severe osteoporosis. Furthermore, 66 patients (26.4%) had blood glucose control that reached the standard, while 176 patients (70.4%) used more than two anti‐diabetic drugs. The serum testosterone level was lower than the median in 87 patients (34.8%) and in 56 smokers (22.4%). Furthermore, 138 patients (55.2%) were overweight and obese, six patients (2.4%) were underweight, 197 patients (78.8%) had chronic diseases, 88 patients (35.2%) were sticking to exercise, and 117 patients (46.8%) had less exercise. In addition, 92 patients (36.8%) were treated with osteotrophy‐protective agents, and 24 patients (9.6%) received anti‐osteoporosis therapy. Smoking, poor glycemic control, low testosterone levels, less exercise, and complications with chronic diseases were the most relevant controllable risk factors.ConclusionFor elderly male osteoporosis patients with type‐2 diabetes, smoking cessation, blood sugar control up to the standard, regular exercise, active prevention and treatment of complications, and appropriate testosterone supplementation are necessary for preventing and curing osteoporosis.  相似文献   
26.
《Immunobiology》2023,228(4):152386
Ulcerative colitis (UC) is a chronic inflammatory disease affecting the colon that can be influenced by microRNAs (miRNAs). This study aims to investigate the impact of miR-146a-5p on lipopolysaccharide (LPS)-induced Caco-2/HT-29 cell autophagy and NLRP3 inflammasome activation and the underlying mechanism, with the aim of identifying potential therapeutic targets. We used LPS to establish Caco-2/HT-29 cell models and measured cell viability by CCK-8. The levels of miR-146a-5p, RNF8, markers of NLRP3 inflammasome activation and autophagy, proteins involved in the Notch1/mTORC1 pathway, and inflammatory factors were assessed by RT-qPCR, Western blot, and ELISA. Intestinal epithelial barrier function was evaluated by measuring transepithelial electrical resistance. Autophagic flux was measured using tandem fluorescent-labeled LC3. miR-146a-5p was highly-expressed in LPS-induced Caco-2/HT-29 cells, and autophagy flux was blocked at the autolysosomal stage after LPS induction. Inhibition of miR-146a-5p suppressed NLRP3 inflammasome activation, reduced intestinal epithelial barrier damage, and facilitated autophagy inhibition in LPS-induced Caco-2/HT-29 cells. The autophagy inhibitor NH4Cl partially nullified the inhibitory effects of miR-146a-5p inhibition on NLRP3 inflammation activation. miR-146a-5p targeted RNF8, and silencing RNF8 partly abrogated the action of miR-146a-5p inhibition on promoting autophagy and inhibiting NLRP3 inflammasome activation. miR-146a-5p inhibition suppressed the Notch1/mTORC1 pathway activation by upregulating RNF8. Inhibition of the Notch1/mTORC1 pathway partially nullified the function of silencing RNF8 on inhibiting autophagy and bolstering NLRP3 inflammasome activation. In conclusion, miR-146a-5p inhibition may be a potential therapeutic approach for UC, as it facilitates autophagy of LPS-stimulated Caco-2/HT-29 cells, inhibits NLRP3 inflammasome activation, and reduces intestinal epithelial barrier damage by upregulating RNF8 and suppressing the Notch1/mTORC1 pathway.  相似文献   
27.
目的:探讨残胃癌的早期诊断方法和外科治疗,观察不同手术方式对预后的影响.方法:对26例残胃癌的临床病理资料进行回顾性分析,比较胃镜和钡餐对残胃癌的诊断价值.结果:胃镜对残胃癌的诊断率为80.8%,钡餐为50.0%.手术切除的20例中根治性残胃切除13例均生存≥3年;姑息性切除7例,术后生存2年5例,1.5年2例.行胃空肠吻合4例中3例于6个月内死亡,1例生存10个月.2例腹腔内广泛转移者仅行肿块活检术.结论:胃镜对残胃癌的诊断价值优于钡餐.早期诊断并行根治性残胃切除患者预后较好.  相似文献   
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ObjectiveRarely the tonsillar pillars and the soft palate became adherent to the posterior nasopharyngeal wall by strong fibrous tissue due to excessive dissection and cauterization during surgery leading to nasopharyngeal stenosis. Therefore, many treatment modalities are being tried to cure this problem. The aim of this study is to explore our results of modifying the basic technique to accommodate those patients with combined nasopharyngeal stenosis and tonsillar pillars adhesions in one stage. Study Design: Case series.MethodsThis study was conducted on 10 patients with combined nasopharyngeal stenosis and tonsillar pillars adhesions after adenotonsillectomy. They were subjected to treatment by palatal eversion through dividing the soft palate in the midline to separate each pillar from the pharyngeal wall in continuation with each half of soft palate and removal of the fibrous tissue causing stenosis. This was followed by eversion and fixation of the two palatal divisions on either side to allow complete epithelialization of the stenotic area. Postoperative follow-up was done for one year by the flexible nasopharyngoscopy, perceptual speech analysis, and polysomnography.ResultsThe flexible nasopharyngosopic examination of the 10 patients at the end of post-operative period revealed a freely mobile soft palate with no nasopharyngeal stenosis or palatal fistula. Velopharyngeal function and speech assessment by perceptual speech analysis was normal in all 10 cases. No obstructive episodes were recorded in polysomnograms.ConclusionsPalatal eversion is a promising technique in the treatment of post-adenotonsillectomy of combined nasopharyngeal stenosis and tonsillar pillars adhesion. It is recommended to be used on a wider scale of patients and other indications as nasopharyngeal stenosis following uvulopalatoplasty and post nasopharyngeal radiotherapy. The level of evidence: 4 (case series).  相似文献   
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