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161.
Meegalla SK Wall MJ Chen J Wilson KJ Ballentine SK Desjarlais RL Schubert C Crysler CS Chen Y Molloy CJ Chaikin MA Manthey CL Player MR Tomczuk BE Illig CR 《Bioorganic & medicinal chemistry letters》2008,18(12):3632-3637
An anti-inflammatory 1,2,4-phenylenetriamine-containing series of FMS inhibitors with a potential to form reactive metabolites was transformed into a series with equivalent potency by incorporation of carbon-based replacement groups. Structure-based modeling provided the framework to efficiently effect this transformation and restore potencies to previous levels. This optimization removed a risk factor for potential idiosyncratic drug reactions. 相似文献
162.
Zhi Yang Qianzhen Zhang Ke Xu Juanjuan Shan Junjie Shen Limei Liu Yanmin Xu Feng Xia Ping Bie Xia Zhang Youhong Cui Xiu-wu Bian Cheng Qian 《PloS one》2012,7(9)
Both adoptive immunotherapy and gene therapy hold a great promise for treatment of malignancies. However, these strategies exhibit limited anti-tumor activity, when they are used alone. In this study, we explore whether combination of cytokine-induced killer (CIK) adoptive immunotherapy with oncolytic adenovirus-mediated transfer of human interleukin-12 (hIL-12) gene induce the enhanced antitumor potency. Our results showed that oncolytic adenovirus carrying hIL-12 (AdCN205-IL12) could produce high levels of hIL-12 in liver cancer cells, as compared with replication-defective adenovirus expressing hIL-12 (Ad-IL12). AdCN205-IL12 could specifically induce cytotoxocity to liver cancer cells. Combination of CIK cells with AdCN205-IL12 could induce higher antitumor activity to liver cancer cells in vitro than that induced by either CIK or AdCN205-IL12 alone, or combination of CIK and control vector AdCN205-GFP. Furthermore, treatment of the established liver tumors with the combined therapy of CIK cells and AdCN205-IL12 resulted in tumor regression and long-term survival. High level expression of hIL-12 in tumor tissues could increase traffic of CIK cells to tumor tissues and enhance their antitumor activities. Our study provides a novel strategy for the therapy of cancer by the combination of CIK adoptive immunotherapy with oncolytic adenovirus-mediated transfer of immune stimulatory molecule hIL-12. 相似文献
163.
Bioreactor cultivation enhances NTEB formation and differentiation of NTES cells into cardiomyocytes
Lü S Liu S He W Duan C Li Y Liu Z Zhang Y Hao T Wang Y Li D Wang C Gao S 《Cloning and stem cells》2008,10(3):363-370
Autogenic embryonic stem cells established from somatic cell nuclear transfer (SCNT) embryos have been proposed as unlimited cell sources for cell transplantation-based treatment of many genetic and degenerative diseases, which can eliminate the immune rejection that occurs after transplantation. In the present study, pluripotent nuclear transfer ES (NTES) cell lines were successfully established from different strains of mice. One NTES cell line, NT1, with capacity of germline transmission, was used to investigate in vitro differentiation into cardiomyocytes. To optimize differentiation conditions for mass production of embryoid bodies (NTEBs) from NTES cells, a slow-turning lateral vessel (STLV) rotating bioreactor was used for culturing the NTES cells to produce NTEBs compared with a conventional static cultivation method. Our results demonstrated that the NTEBs formed in STLV bioreactor were more uniform in size, and no large necrotic centers with most of the cells in NTEBs were viable. Differentiation of the NTEBs formed in both the STLV bioreactor and static culture into cardiomyocytes was induced by ascorbic acid, and the results demonstrated that STLV-produced NTEBs differentiated into cardiomyocytes more efficiently. Taken together, our results suggested that STLV bioreactor provided a more ideal culture condition, which can facilitate the formation of better quality NTEBs and differentiation into cardiomyocytes more efficiently in vitro. 相似文献
164.
165.
Cottam EM Wadsworth J Shaw AE Rowlands RJ Goatley L Maan S Maan NS Mertens PP Ebert K Li Y Ryan ED Juleff N Ferris NP Wilesmith JW Haydon DT King DP Paton DJ Knowles NJ 《PLoS pathogens》2008,4(4):e1000050
Foot-and-mouth disease (FMD) virus causes an acute vesicular disease of domesticated and wild ruminants and pigs. Identifying sources of FMD outbreaks is often confounded by incomplete epidemiological evidence and the numerous routes by which virus can spread (movements of infected animals or their products, contaminated persons, objects, and aerosols). Here, we show that the outbreaks of FMD in the United Kingdom in August 2007 were caused by a derivative of FMDV O(1) BFS 1860, a virus strain handled at two FMD laboratories located on a single site at Pirbright in Surrey. Genetic analysis of complete viral genomes generated in real-time reveals a probable chain of transmission events, predicting undisclosed infected premises, and connecting the second cluster of outbreaks in September to those in August. Complete genome sequence analysis of FMD viruses conducted in real-time have identified the initial and intermediate sources of these outbreaks and demonstrate the value of such techniques in providing information useful to contemporary disease control programmes. 相似文献
166.
BackgroundCirculating tumor cells (CTCs) existing in peripheral blood can be used to predict the prognosis and survival of cancer patients. The study was designed to detect circulating tumor cells and circulating tumor single cell genes by applying microfluidic chip technology. It was used to explore the clinical application value in breast cancer.MethodsWe have developed a size-based CTCs sorting microfluidic chip, which contains a hexagonal array and a micro-pipe channel array to isolate and confirm both single CTCs and CTCs clusters. The sorting performance of the as-fabricated chip was tested by analyzing the clinical samples collected from 129 breast cancer patients and 50 healthy persons.ResultsIn this study, the chip can detect different immunophenotypes of CTCs in breast cancer patients. It was found that the new microfluidic device had high sensitivity (73.6%) and specificity (82.0%) in detecting CTCs. By detecting the blood samples of 129 breast cancer patients and 50 healthy blood donors, it was found that the number of CTCs was not associated with clinical factors such as age, gender, pathological type, and tumor size of breast cancer patients (P > 0.05), but was associated with TNM staging of breast cancer, with or without metastasis (P < 0.005). There was a statistically significant difference in the number of CTCs between luminal A (ER+/PR+/HER2-) and HER-2+ (ER-/PR-/HER2+) (P < 0.05). The best cut-off level distinguished by CTC between the breast cancer patients and the healthy persons was 3.5 cells/mL, with 0.845 for AUC-ROC, 0.790–0.901 for 95% CI, 73.6% for sensitivity, and 82% for specificity (P = 0.000). The combination of CTC, CEA, CA125 and CA153 can provide more effective breast cancer screening.ConclusionsThe CTCs analysis method presented here doesn''t rely on the specific antibody, such as anti-EpCAM, which would avoid the missed inspection caused by antibody-relied methods and offer more comprehensive biological information for clinical breast cancer diagnosis and treatment. 相似文献
167.
为研究冻融作用对泥炭沼泽土壤酶活性的影响,选取金川草本泥炭沼泽为研究对象,采集表层(0-15 cm)和深层(15-30 cm)土壤样品,进行室内冻融模拟实验。实验设置(-5-5℃)和(-10-10℃)两个冻融幅度,分析经0、1、3、5、7、15次冻融循环处理后土壤3种水解酶活性(β-1,4-葡萄糖苷酶(BG)、β-1,4-N-乙酰葡糖胺糖苷酶(NAG)和酸性磷酸酶(AP))和2种氧化酶(过氧化物酶(PER)和多酚氧化酶(PPO))的变化特征,并结合土壤有机碳、氮组分,探讨泥炭沼泽土壤酶活性与土壤活性有机碳、氮组分间的相关关系。结果表明,冻融频次与冻融幅度均显著影响了土壤有机碳、氮组分及土壤酶活性。-10-10℃冻融作用下,土壤可溶性有机碳(DOC)与可溶性有机氮(DON)含量呈现先增加后降低的变化趋势。-5-5℃的冻融作用下土壤DOC与DON释放相对-10-10℃冻融作用更为缓慢,在冻融结束后呈现增加趋势。冻融循环增加了土壤微生物碳(MBC)含量,而降低了土壤微生物氮(MBN)含量。冻融幅度对土壤MBC和MBN的影响表现为-5-5℃ < -10-10℃。随着土层的增加,土壤MBC、MBN和DOC含量的幅度变化表现为0-15 cm < 15-30 cm,而土壤DON含量幅度变化表现为0-15 cm > 15-30 cm。冻融循环降低了土壤水解酶活性和氧化酶活性。冻融幅度对土壤水解酶活性的影响表现为-5-5℃ > -10-10℃,对土壤氧化酶活性的影响表现为-5-5℃ < -10-10℃。随着土层深度的增加,土壤水解酶活性变化的幅度表现为0-15 cm < 15-30 cm,土壤氧化酶活性变化的幅度表现为0-15 cm > 15-30 cm。土壤酶活性与土壤MBC和MBN含量呈正相关,而与土壤DOC含量呈显著负相关(P < 0.05)。研究结果表明冻融作用初期促使部分微生物死亡,其死亡残体释放的可利用养分,促进了适应冻融作用的微生物生长,但在培养后期随着土壤养分的消耗,土壤微生物量呈现下降趋势,进而最终降低了土壤酶活性。 相似文献
168.
169.
超声诊断对输尿管结石的临床价值探讨 总被引:1,自引:0,他引:1
蔡燕敏 《上海生物医学工程》2010,(3):165-166
目的探讨超声诊断输尿管结石的临床价值,并对其声像图进行分析。方法分析我院2008年1月-2009年6月确诊的21例输尿管结石患者的超声声像图及诊断符合率情况。结果21例输尿管结石中超声确诊19例,诊断符合率90.48%。结论超声诊断输尿管结石具有方便、无创,诊断符合率高,值得临床推广和应用。 相似文献
170.
Wu C Ramirez A Cui B Ding J Delcroix JD Valletta JS Liu JJ Yang Y Chu S Mobley WC 《Traffic (Copenhagen, Denmark)》2007,8(11):1503-1520
Rap1 transduces nerve growth factor (NGF)/tyrosine receptor kinase A (TrkA) signaling in early endosomes, leading to sustained activation of the p44/p42 mitogen-activated protein kinases (MAPK1/2). However, the mechanisms by which NGF, TrkA and Rap1 are trafficked to early endosomes are poorly defined. We investigated trafficking and signaling of NGF, TrkA and Rap1 in PC12 cells and in cultured rat dorsal root ganglion (DRG) neurons. Herein, we show a role for both microtubule- and dynein-based transport in NGF signaling through MAPK1/2. NGF treatment resulted in trafficking of NGF, TrkA and Rap1 to early endosomes in the perinuclear region of PC12 cells where sustained activation of MAPK1/2 was observed. Disruption of microtubules with nocodazole in PC12 cells had no effect on the activation of TrkA and Ras. However, it disrupted intracellular trafficking of TrkA and Rap1. Moreover, NGF-induced activation of Rap1 and sustained activation of MAPK1/2 were markedly suppressed. Inhibition of dynein activity through overexpression of dynamitin (p50) blocked trafficking of Rap1 and the sustained phase of MAPK1/2 activation in PC12 cells. Remarkably, even in the continued presence of NGF, mature DRG neurons that overexpressed p50 became atrophic and most (>80%) developing DRG neurons died. Dynein- and microtubule-based transport is thus necessary for TrkA signaling to Rap1 and MAPK1/2. 相似文献