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941.
Objectives: Ex vivo expansion is a feasible strategy, which may overcome limitation of the very low frequency of haematopoietic stem/progenitor cells, in umbilical cord blood (UCB). However, both quality of cells and safety of expanded population are critical issues to be addressed for their clinical application. Hence, in this study, we evaluated genetic stability of UCB‐derived CD34+ cells during ex vivo culture, based on karyotype analysis, as well as its effect on cell proliferation characteristics. Materials and methods: CD34+ cells were isolated from human UCB samples by immunomagnetic separation and were expanded ex vivo over a 28‐day period. Expansion of total nucleate cells, CD34+ cells and CD34+ CD38? cells was investigated. Karyotype analysis of the expanded cells from six randomly selected UCB samples was performed to evaluate their genetic stability. Results: Chromosomal abnormality of expanded cells mainly appeared by day 14, but was seldom sustained until day 28. None of the chromosomal abnormal samples displayed neoplastic proliferation, and expanded cells with altered chromosomes did not show obvious transformation phenomena according to soft agar assay. Conclusions: Ex vivo expansion could lead to occurrence of chromosomal abnormality, although here it did not produce excessive proliferative advantage of the expended cells. Importantly, chromosomal alteration seemed not to be inheritable and unlikely to result in malignant transformation. However, further in‐depth evaluation of potential clinical risks of chromosomal abnormality is warranted. 相似文献
942.
Suppression of RAD21 Induces Senescence of MDA‐MB‐231 Human Breast Cancer Cells Through RB1 Pathway Activation Via c‐Myc Downregulation 下载免费PDF全文
943.
944.
Fan Zhang Ying Li Weiran Xu Liang He Yan Tan 《Bioscience, biotechnology, and biochemistry》2019,83(7):1289-1299
Gastric cancer is a common malignant tumor. Studies from our laboratory or others have shown that long non-coding RNA (lncRNA) zinc finger antisense (ZFAS)1 often acts as an oncogene. However, the molecular underpinnings of how ZFAS1 regulates gastric cancer remain to be elucidated. Results showed that ZFAS1 expression was upregulated, and microRNA-200b-3p (miR-200b) expression was downregulated in gastric cancer tissues. MiR-200b overexpression suppressed the proliferation, cell cycle process, and Wnt/β-catenin signaling of gastric cancer cells. Subsequently, we identified miR-200b is a target of ZFAS1 and Wnt1 is a target of miR-200b. Furthermore, promotion of cancer malignant progression and activation of Wnt/β-catenin signaling induced by ZFAS1 was counteracted by increasing miR-200b expression. In vivo, ZFAS1 knockdown suppressed the tumorigenesis with the upregulated miR-200b and the inactive Wnt/β-catenin signaling. Summarily, we demonstrated a critical role of miR-200b in gastric cancer, and ZFAS1 can promote malignant progression through regulating miR-200b mediated Wnt/β-catenin signaling. 相似文献
945.
同地共栖三种鼠耳蝠食性差异及其生态位分化 总被引:1,自引:0,他引:1
2005年9—11月在贵州省安龙县笃山乡暗河村,分析了共栖同一山洞3种鼠耳蝠的形态特征和食性。在体型上,华南水鼠耳蝠体重为(4.46±0.53)g,前臂长为(34.63±1.45)mm;毛腿鼠耳蝠体重为(5.15±1.76)g,前臂长为(35.20±1.07)mm;西南鼠耳蝠体重为(10.94±0.87)g,前臂长为(45.21±1.15)mm。3种鼠耳蝠的体重两两之间差异显著,西南鼠耳蝠与另外2种鼠耳蝠的前臂长相比两两之间差异显著。在食物组成上,华南水鼠耳蝠主要捕食近水面活动的双翅目及其幼虫,体积百分比和频次百分比分别为79.7%和100%;毛腿鼠耳蝠主要捕食双翅目和小型鞘翅目,体积百分比分别占59.6%和28.8%,频次百分比分别为91.3%和80.1%;西南鼠耳蝠的食物组成主要为近地面或在地表活动的鞘翅目步甲科和埋葬虫科昆虫,体积百分比和频次百分比分别为80.8%和100%;3种鼠耳蝠食物组成存在显著差异。结果表明,同地共栖3种鼠耳蝠除了形态结构上出现差异,食物组成也存在明显的差异。据此,推测3种鼠耳蝠可能采取不同的捕食生境和捕食策略,从而导致捕食生态位分离,避免出现激烈竞争,使得3种近缘鼠耳蝠能够同地共栖。 相似文献
946.
Marlinda Adham Sharon D. Stoker Maarten A. Wildeman Lisnawati Rachmadi Soehartati Gondhowiardjo Djumhana Atmakusumah Djayadiman Gatot Renske Fles Astrid E. Greijer Bambang Hermani Jaap M. Middeldorp I. Bing Tan 《PloS one》2014,9(7)
Background
Nasopharyngeal carcinoma (NPC) is endemic in Indonesia and 20% of the patients are diagnosed before the age of 31. This study evaluates presentation and treatment outcome of young patients in Jakarta, in a tertiary referral centre.Methods
Forty-nine patients under the age of 31, diagnosed with NPC between July 2004 and January 2007, were evaluated. Baseline data included histological type, stage of disease and presenting symptoms. We intended to follow all patients after diagnosis to reveal treatment outcome and overall survival (OS).Results
All but two patients had advanced stage disease (94%), 7 (14%) had distant metastasis. The median interval between start of complaints and diagnosis was 9 months. Forty-two patients were planned for curative intent treatment. Eleven patients (26%) never started treatment, 2 patients did not complete treatment and 3 patients did not return after finishing treatment. Four patients died before radiation could start. Three patients died within 4 months after treatment. Nine patients (21%) had a complete response. Due to the high number of patients who were lost to follow-up (LFU), OS was analyzed as follows: a best-case (patients censored at last contact) and a worst-case scenario (assuming that patients who did not finish treatment or had disease at last contact would have died). The 2-year OS for patients without distant metastases was 39–71%.Conclusion
Treatment outcome for young patients with NPC in this institute was poor. Improvement can be achieved when NPC is diagnosed at an earlier stage and when there is better treatment compliance. 相似文献947.
948.
为研究鸭C4结合蛋白(C4b-binding protein,C4BP)与鸭疫里默氏菌(Riemerella anatipestifer,RA)的相互作用,对鸭C4BPα进行克隆、原核表达,免疫小鼠制备多克隆抗体,并利用间接免疫荧光试验及斑点杂交试验验证C4BP与RA的相互作用。结果显示,鸭C4BPα核苷酸序列全长为1230bp,与鸡C4BPα的相似性最高(82.1%);系统进化树分析发现,鸭C4BPα与鸡C4BPα处于同一系统进化树分支上,两者遗传进化关系最近;C4BPα在大肠杆菌Escherichia coli BL21 (DE3)中能高效表达,重组蛋白以胞内可溶性形式存在;多克隆抗体效价超过1∶10000,并且可以与重组蛋白发生特异性反应;间接免疫荧光试验和斑点杂交试验结果显示RA与鸭C4BP可以发生相互作用。研究结果为进一步揭示RA的致病机制奠定了基础。 相似文献
949.
Toby K McGovern William S Powell Brian J Day Carl W White Karuthapillai Govindaraju Harry Karmouty-Quintana Normand Lavoie Ju Jing Tan James G Martin 《Respiratory research》2010,11(1):138
Background
Exposure to chlorine (Cl2) causes airway injury, characterized by oxidative damage, an influx of inflammatory cells and airway hyperresponsiveness. We hypothesized that Cl2-induced airway injury may be attenuated by antioxidant treatment, even after the initial injury.Methods
Balb/C mice were exposed to Cl2 gas (100 ppm) for 5 mins, an exposure that was established to alter airway function with minimal histological disruption of the epithelium. Twenty-four hours after exposure to Cl2, airway responsiveness to aerosolized methacholine (MCh) was measured. Bronchoalveolar lavage (BAL) was performed to determine inflammatory cell profiles, total protein, and glutathione levels. Dimethylthiourea (DMTU;100 mg/kg) was administered one hour before or one hour following Cl2 exposure.Results
Mice exposed to Cl2 had airway hyperresponsiveness to MCh compared to control animals pre-treated and post-treated with DMTU. Total cell counts in BAL fluid were elevated by Cl2 exposure and were not affected by DMTU treatment. However, DMTU-treated mice had lower protein levels in the BAL than the Cl2-only treated animals. 4-Hydroxynonenal analysis showed that DMTU given pre- or post-Cl2 prevented lipid peroxidation in the lung. Following Cl2 exposure glutathione (GSH) was elevated immediately following exposure both in BAL cells and in fluid and this change was prevented by DMTU. GSSG was depleted in Cl2 exposed mice at later time points. However, the GSH/GSSG ratio remained high in chlorine exposed mice, an effect attenuated by DMTU.Conclusion
Our data show that the anti-oxidant DMTU is effective in attenuating Cl2 induced increase in airway responsiveness, inflammation and biomarkers of oxidative stress. 相似文献950.
Angele V. McGrady Robert Yonker S. Y. Tan Thomas H. Fine Marilynn Woerner 《Applied psychophysiology and biofeedback》1981,6(3):343-353
The effect of EMG biofeedback-assisted relaxation on blood pressure and selected biochemical parameters was evaluated in 38 patients with essential hypertension. Training consisted of 8 weeks of biofeedback and home practice of relaxation exercises. Mean blood pressure decreased in the experimental group from 144/90 to 133/84 mm Hg while the control group remained unchanged. Statistically significant decreases in the experimental group also occurred in muscle tension levels, in plasma aldosterone, and in urinary cortisol. Both aldosterone and cortisol are secreted by the adrenal cortex. It was concluded that the technique taught to the experimental group produced a reduction in skeletal muscle tension and a decrease in stress responding mediated by the adrenal cortex.This work was supported by the Northwestern Ohio Heart Association Grant No. 93298. It was presented as a citation paper at the meetings of the Biofeedback Society in 1979 and 1980. 相似文献