Morphine Preconditions Purkinje Cells against Cell Death under In Vitro Simulated Ischemia-Reperfusion Conditions

Background: Morphine pretreatment via activation of [delta]1-opioid receptors induces cardioprotection. In this study, the authors determined whether morphine preconditioning induces ischemic tolerance in neurons.

Methods: Cerebellar brain slices from adult Sprague-Dawley rats were incubated with morphine at 0.1-10 [mu]m in the presence or absence of various antagonists for 30 min. They were then kept in morphine- and antagonist-free buffer for 30 min before they were subjected to simulated ischemia (oxygen-glucose deprivation) for 20 min. After being recovered in oxygenated artificial cerebrospinal fluid for 5 h, they were fixed for morphologic examination to determine the percentage of undamaged Purkinje cells.

Results: The survival rate of Purkinje cells was significantly higher in slices preconditioned with morphine (>= 0.3 [mu]m) before the oxygen-glucose deprivation (57 +/- 4% at 0.3 [mu]m morphine) than that of the oxygen-glucose deprivation alone (39 +/- 3%, P < 0.05). This morphine preconditioning-induced neuroprotection was abolished by naloxone, a non-type-selective opioid receptor antagonist, by naltrindole, a selective [delta]-opioid receptor antagonist, or by 7-benzylidenenaltrexone, a selective [delta]1-opioid receptor antagonist. However, the effects were not blocked by the [mu]-, [kappa]-, or [delta]2-opioid receptor antagonists, [beta]-funaltrexamine, nor-binaltorphimine, or naltriben, respectively. Morphine preconditioning-induced neuroprotection was partially blocked by the selective mitochondrial adenosine triphosphate-sensitive potassium channel antagonist, 5-hydroxydecanoate, or the mitochondrial electron transport inhibitor, myxothiazol. None of the inhibitors used in this study alone affected the simulated ischemia-induced neuronal death.     

Quantifying the blood oxygenation level dependent effect in cerebral blood volume-weighted functional MRI at 9.4T.

In cerebral blood volume (CBV)-weighted functional MRI (fMRI) employing superparamagnetic contrast agent, iron dose and blood oxygenation level dependent (BOLD) contamination are two important issues for experimental design and CBV quantification. Both BOLD and CBV-weighted fMRI are based upon the susceptibility effect, to which spin-echo and gradient-echo sequences have different sensitivities. In the present study, CBV-weighted fMRI was conducted using spin-echo and gradient-echo sequences at 9.4T by systematically changing the doses of contrast agent. Results suggest that BOLD contamination is a significant component in CBV-weighted fMRI at high field, particularly when relatively low dose of contrast agent is administered. A mathematical model was developed to quantify the extravascular (EV) BOLD effect. With a TE of 35 ms, the EV BOLD effect was estimated to account for 76+/-12% of the observed spin-echo fMRI signal at 9.4T. These data suggest that correcting BOLD effect may be necessary for accurately quantifying activation-induced CBV changes at high field.     

急性中毒病例流行病学特征及救治对策

目的研究安徽省肥西县急性中毒病例的临床特点和发病规律,为更有效地提高该地区急性中毒患者的抢救成功率和做好中毒防范工作提供科学依据。方法采取分层随机整群抽样方法随机抽取肥西县县级综合医院、乡镇中心卫生院、乡镇普通卫生院各一所,研究这3所医院2006年1月1日~2008年12月31日就诊的所有初诊中毒患者。结果共报告有效病例798例,其中男性481名,女性317名,性别比1.52∶1,平均年龄为（37.96±15.78）岁,中毒发生时间多集中在13~14点（19.30%）和20~21点（22.81%）,中毒就诊时间平均为1.85 h,中毒死亡率为3.38%。结论急性中毒发生率、死亡率高,急救医务人员应采取针对性和预防性措施,提高救治成功率。     

电针对大鼠脑局部缺血-再灌流损伤的保护作用

再灌流前电针“环跳”穴３０ｍｉｎ，观察对左大脑中动脉（ＭＣＡ）缺血 再灌流模型大鼠早期运动功能、自由基代谢、脑水肿及神经电生理活动的影响。结果：缺血再灌＋针刺组大鼠再灌流后神经功能缺损状况有较明显的改善，病灶侧脑组织过氧化物歧化酶（ＳＯＤ）活性及丙二醛（ＭＤＡ）含量恢复到接近假手术对照组的水平。皮层体感诱发电位（ＳＥＰ）测量表明缺血侧Ｐ１潜伏期及Ｐ１ Ｎ１波幅亦有显著性改善。结果表明：于再灌流前电针处理对本模型脑缺血 再灌流损伤有保护作用     

锌离子对大鼠海马突触体Ca^2＋—Mg^2＋ATP酶活性及蛋白合成的影响

行为实验己经证明，锌过多或缺锌均可影响脑功能。锌作为体内重要的微量元素，影响多种酶的活性及蛋白质和核酸的台成。本实验通过体外分离大鼠脑海马突触体，观察不同浓度锌离子对Ca2 －Mg2 ATP酶的活性和3H－Leu掺入突触蛋白合成的影响．结果表明：1．锌离子浓度在25μmol／L时增加该酶的活性（＜0．01），并促进3H－Leur掺入蛋白质的合成（＜0．05）。2．锌离子在50,100，200μmol／L的较高浓度时对Co2 －M2 ATP酶的活性有显著的抑制作用（分别为：P＜0.05．P＜0．01，P＜0.01），仅200μmol／L对3H—Leu掺入突触蛋白合成有抑制作用。本研究提示：适量的锌对突触体功能的维持是必要的，但剂量过高则起相反作用。     

Effects of Volatile Anesthetics on Glutamate Transporter, Excitatory Amino Acid Transporter Type 3: The Role of Protein Kinase C

Background: Glutamate transporters play an important role in maintaining extracellular glutamate homeostasis. The authors studied the effects of volatile anesthetics on one type of glutamate transporters, excitatory amino acid transporter type 3 (EAAT3), and the role of protein kinase C in mediating these effects.

Methods: Excitatory amino acid transporter type 3 was expressed in Xenopus oocytes by injection of EAAT3 mRNA. Using two-electrode voltage clamp, membrane currents were recorded before, during, and after application of l-glutamate. Responses were quantified by integrating the current trace and are reported as microcoulombs. Data are mean +/- SEM.

Results: l-Glutamate-induced responses were increased gradually with the increased concentrations of isoflurane, a volatile anesthetic. At 0.52 and 0.70 mm isoflurane, the inward current was significantly increased compared with control. Isoflurane (0.70 mm) significantly increased Vmax (maximum velocity) (3.6 +/- 0.4 to 5.1 +/- 0.4 [mu]C;P < 0.05) but not Km (Michoelis-Menten Constant) (55.4 +/- 17.0 vs. 61.7 +/- 13.6 [mu]m;P > 0.05) of EAAT3 for glutamate compared with control. Treatment of the oocytes with phorbol-12-myrisate-13-acetate, a protein kinase C activator, caused a significant increase in transporter current (1.7 +/- 0.2 to 2.5 +/- 0.2 [mu]C;P < 0.05). Responses in the presence of the combination of phorbol-12-myrisate-13-acetate and volatile anesthetics (isoflurane, halothane, or sevoflurane) were not greater than those when volatile anesthetic was present alone. Oocytes pretreated with any of the three protein kinase C inhibitors alone (chelerythrine, staurosporine, or calphostin C) did not affect basal transporter current. Although chelerythrine did not change the anesthetic effects on the activity of EAAT3, staurosporine or calphostin C abolished the anesthetic-induced increase of EAAT3 activity.     

关节镜下射频汽化结合髌骨周围钻孔减压治疗髌骨软骨病

目的: 研究射频汽化结合髌骨钻孔减压在治疗髌骨软骨病变中的临床效果。方法: 利用ArthroCare2000射频汽化仪对 56例髌骨软骨病变患者行损伤的软骨面修整, 髌骨周缘滑膜清理; 直径 2~2. 5mm克氏针, 自髌骨两侧缘向髌骨内钻孔减压。9例同时行外侧支持带松解。结果: 随访 6个月~2年 10个月, 平均 1年 7个月。术后患者疼痛症状明显缓解。Lysholm评分由术前平均 56分提高到术后平均 91分。结论: 射频汽化仪治疗精确, 最大限度地保留了未受损伤的软骨组织; 联合髌骨钻孔减压治疗髌骨软骨病变效果良好, 术后康复快。     

晚期肺癌的中医证候研究

目的　探讨晚期肺癌的主要中医证候。方法　采用回顾性与前瞻性相结合的方法进行临床观察。结果　经 χ2 检验 ,不同中医证候的晚期肺癌组之间有显著性差异 (P <0 0 1) ,而血瘀证、气虚证、痰证、阴虚证最为多见 ;晚期非小细胞肺癌与晚期小细胞肺癌的中医证型没有显著性差异。结论　晚期肺癌的中医证候以血瘀证、气虚证、痰证、阴虚证为主 ;晚期非小细胞肺癌与小细胞肺癌的中医证候无明显差异。     

三种蚊唾腺蛋白IgE亲和成分的初步分析

从我国分布较广的三种蚊中华按蚊、淡色库蚊和白纹伊蚊中分离出唾液腺 ,制成唾腺蛋白粗提物 ,再应用ELISA、竞争抑制ELISA和免疫印迹试验分析其与IgE结合的组分。结果显示三种蚊唾腺蛋白含能与IgE结合的成分 ,以白纹伊蚊反应所呈现的A值最高 ;免疫印迹在三种蚊均显示 4条阳性带 ,中华按蚊和淡色库蚊相似 ,白纹伊蚊有 3条带差异 ,但其相对分子质量为 30 0 0 0～ 310 0 0组分阳性条带均出现于三种蚊唾腺蛋白     

Diagnosis of Kala-Azar by Nested PCR Based on Amplification of the Leishmania Mini-Exon Gene

To diagnose visceral leishmaniasis (kala-azar), we have developed a nested PCR method based on amplification of the mini-exon gene, which is unique and tandomly repeated in the Leishmania genome. Nested PCR was sufficiently sensitive for the detection of DNA in an amount equivalent to a single Leishmania parasite or less. We examined the usefulness of this PCR method using bone marrow aspirates and buffy coat cells collected from kala-azar patients who had or had not received chemotherapy in northwest China. We obtained PCR positivity for all of the parasitologically positive bone marrow samples from the patients. Some ambiguities with the primary PCR results were eliminated by the subsequent nested PCR. The buffy coat samples from 7 of 12 patients with splenomegaly were positive by the nested PCR, although only 2 of them were positive for parasites by culture. However, buffy coat samples from nine children, whose splenomegaly has been reduced and clinically cured by antimony treatment, were all negative. Thus, this nested PCR method represents a new tool for the diagnosis of kala-azar with patient blood samples instead of bone marrow or spleen aspirates obtained by more invasive procedures.