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71.
72.
Studies were undertaken to manufacture a multivalent Shigella inactivated whole-cell vaccine that is safe, effective, and inexpensive. By using several formalin concentrations, temperatures, and incubation periods, an optimized set of inactivation conditions was established for Shigella flexneri 2a, S. sonnei, and S. flexneri 3a to produce inactivated whole cells expressing a full repertoire of Ipa proteins and lipopolysaccharide (LPS). The inactivation conditions selected were treatment with 0.2% formalin (S. flexneri 2a and 3a) or 0.6% formalin (S. sonnei) for 48 h at 25°C. Vaccine formulations prepared under different inactivation conditions, in different doses (10E5, 10E7, and 10E9 cells), and with or without the inclusion of double-mutant heat-labile toxin (dmLT) were evaluated in mice. Two intranasal immunizations with ≥10E7 inactivated whole cells resulted in high levels of anti-Invaplex and moderate levels of LPS-specific IgG and IgA in serum and in lung and intestinal wash samples. Addition of dmLT to the vaccine formulations did not significantly enhance humoral immunogenicity. Minimal humoral responses for IpaB, IpaC, or IpaD were detected after immunization with inactivated whole Shigella cells regardless of the vaccine inactivation conditions. In guinea pigs, monovalent formulations of S. flexneri 2a of 3a or S. sonnei consisting of 10E8, 10E9, or 10E10 cells were protective in a keratoconjunctivitis assay. A trivalent formulation provided protection against all three serotypes (S. flexneri 2a, P = 0.018; S. flexneri 3a, P = 0.04; S. sonnei, P < 0.0001). The inactivated Shigella whole-cell vaccine approach incorporates an uncomplicated manufacturing process that is compatible with multivalency and the future development of a broadly protective Shigella vaccine.  相似文献   
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Conventional high‐grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis‐free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti‐apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell‐cycle arrest; Chk1 protein levels were attenuated and ATR–Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven‐depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven‐controlled ATR–Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix‐embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR–Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
75.
目的:探索可早期预测严重败血症病人死亡的临床和实验室指标或系统模型。方法:对ICU连续收治的26例严重败血症病人行前瞻性观察28天,分析其死亡的相关临床和实验室指标。结果:共有14人(54%)死亡,多死于第1周内(74%)。根据循环中的细胞间粘附分子-1水平能早期预测其脏器衰竭和死亡。一些临床指标水平在死亡病人与生存病人之间差别较大,其中包括血总胆红素、pH值、红细胞压积、氧合指数、动静脉血氧差、四项SIRS指标和一些血流动力学指标等。结论:综合上述指标可以尝试建立起了一个能够早期评估病人死亡可能性的积分系统。  相似文献   
76.
目的 克隆人2型大麻受体(hCB2)基因,并构建相应的稳定表达细胞株.方法 利用人T淋巴细胞株HPB-ALL的总RNA,以RT-PCR及酶切、连接等分子生物学方法克隆hCB2基因于质粒载体pFlag-CMV-3内,以HEK293细胞构建稳定表达细胞株,以Western blot方法利用蛋白标记Flag的单克隆抗体(Anti-Flag)和CB2多克隆抗体(Anti-CB2)同时检测质粒的表达.结果 酶切及测序结果表明hCB2基因克隆成功,Western blot检测结果表明Anti-Flag和Anti-CB2都能检测Flag-hCB2蛋白.结论 成功克隆hCB2基因,并获得稳定表达细胞株,同时证实Anti-CB2多克隆抗体有效.  相似文献   
77.
Extrathoracic esophagectomy has the potential of improving the results of resectional therapy for carcinoma of the esophagus by eliminating the need for thoracotomy and decreasing postoperative pulmonary complications. This report compares the operative and functional results of blunt extrathoracic esophagectomy and substernal reversed gastric tube reconstruction in patients with esophageal cancer to results in 10 consecutive nonrandomized control patients treated by standard esophagogastrectomy. Extrathoracic esophagectomy was associated with greater pulmonary dysfunction than standard esophagogastrectomy. While there was no significant difference in survival in the two groups, three patients in the standard esophagogastrectomy group (mean survival 9.0 months) and none in the extrathoracic esophagectomy group (mean survival 7.4 months) developed anastomotic recurrence. Extrathoracic esophagectomy evidently does not afford patients with esophageal carcinoma better palliation than standard esophagogastrectomy.  相似文献   
78.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析.  相似文献   
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Colorectal cancer screening guidelines are identical for men and women despite reported differences in epidemiology, endoscopy performance, screening preferences, and screening uptake. High-quality research is needed to determine whether gender aspects may in real world increase acceptance and overcome screening barriers, which may lead to better use of limited resources allocated for public health.  相似文献   
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