The neuroprotective effects of K252a through inhibiting MLK3/MKK7/JNK3 signaling pathway on ischemic brain injury in rat hippocampal CA1 region

It has been well documented that the activation of c-Jun N-terminal protein kinase (JNK) pathway and caspase-3 signal are involved in the delayed neuronal cell death in cerebral ischemia. In this study, we first detected the activation pattern of JNK signaling including mixed lineage kinase (MLK)3, mitogen-activated protein kinase kinase (MKK)7 and JNK3 in hippocampal CA1 and CA3/DG regions at various time points after 15 min of ischemia. These results indicated that cerebral ischemia induced the continuous activation of MLK3/MKK7/JNK3 cascade, which all had two active waves only in the CA1 region. We also detected the phosphorylation of JNK substrates c-Jun and Bcl-2, and the activation of a key protease of caspase-3 in CA1 region, which only had one active peak, respectively. Because K252a has recently been shown to be a potent inhibitor of MLK3 activity both in vivo and in vitro, we further examined the possible effects and mechanism of this interesting drug in cerebral ischemia. In our present paper, we found that administration of K252a 20 min prior to ischemia inhibited MLK3/MKK7/JNK3 signaling, Bcl-2 phosphorylation, the activation of c-Jun and caspase-3, but had no significant effects on these protein expressions. Additionally, pretreatment of K252a significantly increased the number of the surviving CA1 pyramidal cells at 5 days of reperfusion. Our results suggest that K252a play a neuroprotective role in ischemic injury via inhibition of the JNK pathway, involving the death effector of caspase-3. Thus, JNK signaling may eventually emerge as a prime target for novel therapeutic approaches to treatment of ischemic stroke, and K252a may serve as a potential and important neuroprotectant in therapeutic aspect in ischemic stroke.     

磷酸钛钾激光声带切除术不同术式的临床特点

目的 探讨支撑喉镜下磷酸钛钾（ｐｏｔａｓｉｕｍ ｔｉｔａｎｉｕｍ ｐｈｏｓｐｈａｔｅ,ＫＴＰ）激光声带切除术不同术式的选择及愈合过程中的临床特点。方法 选择７６例早期声门型喉癌行ＫＴＰ激光声带切除术,对不同术式术后喉内结构恢复过程、音质变化等进行随访观察记录。结果 Ⅰ型术式１１例,３个月后恢复喉的正常结构及功能;Ⅱ型术式５０例,３个月后有声带样粘膜皱襞（以下称新声带）形成,基本恢复喉的结构;Ⅲ型术     

Microsomal casein kinase II in endoplasmic reticulum- and Golgi apparatus-rich fractions of ROS 17/2.8 osteoblast-like cells: An enzyme that modifies osteopontin

Osteopontin is an acidic phosphoprotein containing casein kinase II (CKII) phosphorylatable sites and an acidic amino acid cluster. The metabolically ³²P-labelings of both serines and threonines in vitro in osteopontin immunoprecipitated from rat osteoblast-like ROS 17/2.8 cells may suggest that casein kinase II catalyzes this modification. The enzyme occurs in microsomal fractions of rat osteoblast-like ROS 17/2.8 cells. Subcellular fractions containing endoplasmic reticulum and Golgi apparatus were isolated by differential centrifugation and were identified according to their ultrastructures and the presence of marker enzymes such as glucose-6-phosphatase and thiamine pyrophosphatase, respectively. Both fractions phosphorylated the partially dephosphorylated osteopontin and the specific substrate peptide RRREEETEEE. Endoplasmic reticulum-catalyzed peptide phosphorylation was 2.7 times lower than that of Golgi although both endoplasmic reticulum- and Golgi-catalyzed peptide reactions were 50% inhibited by 20 and 100 ng/ml heparin, respectively. Western blot analysis revealed that both fractions contained osteopontin and microsomal CKII. Furthermore, microsomal CKII was immunogold-labeled in endoplasmic reticulum and Golgi apparatus. Heparin inhibition and utilization of [-³²P]GTP as a phosphate donor by both fractions confirmed their capacity to phosphorylate osteopontin. The results suggest that microsomal CKII modifies the acidie matrix proteins during transportation. These matrix phosphoproteins may participate in the mineralization process of hard tissues.     

医疗机构产权制度改革及其监管

本文从产权的角度出发,对当前的医疗机构改革进行了分析,并对医疗机构自主经营、企业化经营过程中可能出现的一些问题,提出了政府作为财产的最终所有者应加强对医疗机构经营状况的监管。     

红景天提取物的制备及其抗缺氧抗疲劳作用

目的 :探讨红景天对提高缺氧耐力和劳动能力的机理 ,为提高运动能力和在缺氧环境下的工作能力提出防护办法。方法 :对红景天提取物进行初步纯化 ,以小鼠常压缺氧和力竭游泳时间作为耐氧能力和劳动能力指标 ,对动物服药前后的体重变化进行考察。结果 :红景天可明显提高动物的缺氧耐力和劳动能力 ,减轻体重。提示服用红景天可以作为缺氧环境下提高工作能力的有效措施 ,并可作为舰艇长航人员防止体力耐力下降、肥胖人员减肥、轻量级运动员提高运动能力的保健药物。     

测定尿红细胞平均体积和分布曲线鉴别血尿来源的临床价值

目的观察尿红细胞平均体积（ＭＣＶ）和尿红细胞分布曲线鉴别血尿来源和性质。方法用ＣＯＵＬＴＥＲ－ＪＴ全自动血球计数仪检测４０例肾小球性血尿、４０例非肾小球性血尿ＭＣＶ和分布曲线。结果肾小球肾炎ＭＣＶ为６１±１４ｆｌ,非肾小球肾炎ＭＣＶ为８９±１８ｆｌ,以ＭＣＶ＜８０ｆｌ鉴别为肾小球性血尿,敏感性和特异性分别为９７．５％和８８．２％。分布曲线的特点不同,峰值差异很大。结论测定尿ＭＣＶ及分布曲线对鉴别血尿来源和性质有重要意义。     

联合内分泌治疗对前列腺和睾丸的影响

目的 探讨抑那通和缓退瘤联合治疗对正常前列腺,增生的前列腺（ＢＰＨ）和前列腺癌以及睾丸的作用。方法 对１６例接受联合内分泌治疗至少３个月且有治疗前后病理资料的前列腺癌患者的标本进行了系统的病理学检查。对内分泌治疗后的睾丸标本与同龄未接受治疗的进行对照研究。结果 １４例内分泌治疗后的前列腺标本２例未见残存癌灶,９例对治疗有明显的反应;３例对治疗反应差,治疗并未降低前列腺癌的病理分期。３例内分泌治疗后