Long-term protection against Argentine hemorrhagic fever in Tacaribe virus infected marmosets: virologic and histopathologic findings

Tacaribe virus may represent a better alternative than attenuated strains of Junin virus (JV) for immunization against Argentine hemorrhagic fever (AHF) because of possible risk of persistent infection of disease associated with live, attenuated strains. Callithrix jacchus marmosets, which suffer 100% mortality if inoculated with the pathogenic XJ strain of JV, were used to evaluate possible Tacaribe virus persistence, subclinical, or long-term disease and the duration of protection against challenge with JV. Histologic studies did not show pathogenic changes due to Tacaribe virus in primates sacrificed from 7 to 480 days postinoculation (pi). No virus was recovered in tissue samples after primary culture or cocultures with sensitive cells. The presence of anti-Tacaribe neutralizing serum antibodies and protection against pathogenic JV were detected up to 480 days after a single dose of Tacaribe virus. However, anti-Junin antibodies were detected only after challenge. In other experiments, protection against JV was evaluated histologically and virologically. Two primates were immunized with Tacaribe virus, challenged with JV, and sacrificed 18 or 21 days later. Subclinical histopathologic findings were associated with recovery of JV only by the sensitive primary culture-coculture techniques. The immunogenicity, degree of protection, and safety of Tacaribe virus indicate its potential as a vaccine against human AHF.     

葡萄糖酸镁灌胃对大鼠异丙肾上腺素心肌损伤的影响

用大鼠异丙肾上腺素心肌损伤模型,研究了葡萄糖酸镁胃内给药的心肌保护作用。结果表明,葡萄糖酸镁胃内给药能减少异丙肾上腺素所致的心肌细胞Mg~(2+)丢失和Ca~(2+)聚积,减轻心肌组织脂质过氧化损害,抑制细胞内乳酸脱氢酶的释放,并能显著地减轻异丙肾上腺素引起的心肌肥大或/和水肿等病理损伤。证实了葡萄糖酸镁胃肠道给药具有一定的心肌保护作用,为其临床应用提供了实验依据。     

内皮素在评价不阻断升主动脉低温室颤对心肌保护作用中的应用

①目的探讨体外循环条件下低温室颤技术对心肌的保护作用。②方法14只健康成年犬随机分为两组，低温停跳组(n=7)与低温室颤组(n=7)，分别检测两组手术前、手术1、2小时和复跳后1小时4个时间点血内皮素(ET)的水平。③结果室颤组ET水平明显低于停跳组。④结论通过内皮素水平的变化，说明体外循环条件下低温室颤技术是一种安全、有效的心肌保护方式，优于传统低温停跳技术。     

Reinfusion potassium blood cardioplegia versus cold blood reinfusion alone in elective revascularization

The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CB C (10 cc/kg) with potassium. Group I patients (n=23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n=17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.     

茶黄素对大鼠心脏缺血/再灌注损伤的保护作用

目的探讨茶黄素对大鼠心脏缺血/再灌注损伤的保护作用及其机制。方法将雄性SD大鼠随机分为对照组和茶黄素组。利用Langendorff灌注技术,使心脏缺血30min再灌注120min,建立大鼠离体心脏全心缺血/再灌注(I/R)损伤模型,观察茶黄素对缺血/再灌注后心肌梗死面积以及心肌超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量的变化。结果与对照组相比,茶黄素组可剂量依赖性地改善大鼠缺血/再灌注损伤后心肌的梗死面积。茶黄素组大鼠缺血/再灌注后心肌SOD活性明显高于对照组,而MDA含量则低于对照组。结论茶黄素具有明显的抗心肌缺血/再灌注损伤作用,此作用与茶黄素的抗氧化作用有关。     

弥散张量成像对胶质瘤手术风险的评估

Objective To elucidate the clinical significance of diffusion tensor imaging (DTI) mainly used for protecting neurological functions in patients with gliomas. Methods Thirty - eight patients with gliomas were recruited to undergo DTI test and assess the status of neurological functions before and after surgery. According to the relationships between gliomas and adjacent white matter(WM) tracts, DTI can be classfied as the following types : type Ⅰ - displacement; type Ⅱ - Infiltration; type Ⅲ - Disruption. The neurological functions before surgery were compared in three groups,as well as the change of neurological functions after surgery was also compared in three groups. Results There were 14 cases in type Ⅰ , 16 cases in type Ⅱ, and 8 cases in type Ⅲ. There were significant difference between DTI types and preoperative neurological functions, as well as between DTI types and the change of postoperative neurological functions ( P < 0. 05 ). Conclusions DTI allows to visualizate the relationships of gliomas and adjacent WM tracts, which represent the different growth patterns of gliomas. It is useful for neurosurgeons to select suitable surgical approaches and determine appropriate extent of resection.     

阿司匹林对大鼠脊髓损伤细胞凋亡的保护作用

目的 观察阿司匹林对大鼠慢性压迫性脊髓损伤后神经细胞凋亡及神经功能恢复的影响。方法选择65只体重为220～250g的Wistar大鼠（雌雄不限），于T10部位置入后路渐进式压迫装置，制作成慢性压迫性脊髓损伤模型。随机分为阿司匹林治疗组（A组，30只）、生理盐水对照组（B组，30只）和假手术组（C组，5只）。应用原位末端脱氧核糖核苷酸转移酶介导dUTP标记技术，分别于慢性压迫性脊髓损伤后1、3、7、14、28d做行为学评价，并取材对脊髓损伤区进行细胞凋亡检测。结果A、B组均发现细胞凋亡，A组与B组细胞凋亡率相比差异有显著性（P〈0．05），A组与B组行为学评价相比差异有显著性（P〈0．05），神经细胞凋亡情况与运动功能改变具有相关性。结论 阿司匹林对慢性脊髓压迫损伤后所导致的神经细胞凋亡产生抑制作用。     

IL-1Ra基因多态性在冠心病病人心血管事件中的作用

目的 探讨白细胞介素-1受体拮抗剂(interleukin-1 receptor antagonist,IL-1Ra)基因多态性与冠心病患病率及心血管事件发生的关系.方法 利用聚合酶链式反应(PCR)技术对220例冠心病患者及100例正常对照者IL-1Ra基因进行扩增;检测冠心病患者的高敏感性C反应蛋白、血清总胆固醇、甘油三酯、低密度脂蛋白和体重指数;所有冠心病患者随访12个月,了解患者在出院后1年内的心血管事件.结果 冠心病患者和正常人的IL-1Ra基因多态性分布的差别没有统计学意义;出院后未发生心血管事件的冠心病患者Ⅱ型基因型携带率高于其他基因型.结论 监测IL-1Ra基因多态性不能预测冠心病的发生;但其多态性中Ⅱ型基因对已患冠心病患者的预后有一定保护作用.     

Transforming growth factor alpha treatment alters intracellular calcium levels in hair cells and protects them from ototoxic damage in vitro

To determine if transforming growth factor alpha (TGFα) pretreatment protects hair cells from aminoglycoside induced injury by modifying their intracellular calcium concentration, we assayed hair cell calcium levels in organ of Corti explants both before and after aminoglycoside (i.e. neomycin, 10⁻³M) exposure either with or without growth factor pretreatment. After TGFα (500ng/ml) treatment, the intracellular calcium level of hair cells showed a five-fold increase as compared to the levels observed in the hair cells of control cultures. After ototoxin exposure, calcium levels in hair cells of control explants showed an increase relative to their baseline levels, while in the presence of growth factors pretreatment, hair cells showed a relative reduction in calcium levels. Pretreatment of organ of Corti explants afforded significant protection of hair cell stereocilia bundle morphology from ototoxic damage when compared to explants exposed to ototoxin alone. This study correlates a rise in hair cell calcium levels with the otoprotection of hair cells by TGFα in organ of Corti explants.