Neuropeptide levels in the basal ganglia of aged common marmosets following prolonged treatment with MPTP

Summary Aged common marmosets were treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP; 0.5–2.0 mg/kg/week i.p.) for 16 or 24 weeks, observed for a total of 30 weeks and then killed for measurement of biochemical pramaters in basal ganglia. The MPTP treatment induced a marked depletion in dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid levels in the caudate nucleus and putamen. In contrast, the concentrations of five neuropeptides: [Met⁵]-enkephalin, [Leu⁵]-enkephalin, cholecystokinin, substance P and neurotensin as measured by a combined HPLC/RIA method, remained unaltered in all basal ganglia regions examined. Enkephalin precursor levels, as reflected by cryptic [Met⁵]-enkephalin content, were increased in the putamen, but not in the caudate nucleus, as a consequence of MPTP administration. Cryptic [Leu⁵]-enkephalin content remained unchanged in the striatum of MPTP treated marmosets. Overall, these results suggest an increase in striatal [Met⁵]-enkephalin release following chronic MPTP treatment of aged marmosets. However, the chronic treatment of aged marmosets with MPTP does not reproduce the neuropeptide alterations characteristic of Parkinson's disease.     

碳纤维根管桩的研制

目的研究高强度碳纤维增强复合树脂根管桩的加工成型工艺.方法用湿法制备碳纤维预浸料,在预成型模具中预成型,然后在成型模具中经特殊的工艺进行成型,最后用车床加工成预定形状的桩钉;并测试其弯曲强度、剪切强度和碳纤维含量.结果随着碳纤维含量的增加,根管桩的弯曲强度和剪切强度均逐渐增加.碳纤维含量达到67.13%时,弯曲强度和剪切强度分别达到406MPa和653.86MPa.结论高强度的碳纤维根管桩可以满足临床需要.     

Photolysis and ozonolysis of (iso) desmosine-containing crosslinked peptides from porcine aorta elastin

This report describes the use of photolysis and ozonolysis as a means of achieving complete cleavage of the pyridinium ring of (iso)desmosine in crosslinked elastin peptides. Although photolysis leads to the opening of the ring with concomitant formation of lysine, the peptide chains remain attached. Subsequent ozonolysis is able to completely achieve the cleavage of the rest of the ring skeleton, thus leading to the separation of the peptide chains. Formation of new amino acids, i.e. α-aminoadipic and glutamic acids, is emphasized. Localization of these amino acids within the released peptides should be of help in structural investigations on the crosslinking zones involving either isodesmosine or desmosine. However, other amino acids such as tyrosine and phenylalanine are sensitive to this procedure and side reactions occur which are responsible for peptide bond cleavage with the formation of breakdown products.     

早期应用纳洛酮治疗急性重症颅脑损伤

目的 观察早期应用纳洛酮对急性重症颅脑损伤的临床疗效及对改善预后的影响.方法 62例急性重症颅脑损伤患者按就诊顺序分为治疗组30例和对照组32例,所有患者均给予脱水剂、镇静类、钙离子拮抗剂等药物,以及吸氧、支持、亚低温冬眠和抗感染治疗.治疗组除采用以上常规处理外,均在入院后6 h内应用纳洛酮,剂量为0.4 ms/(kg·d),生理盐水稀释至500 ml,用输液泵24 h持续静脉输入,3 d后改为0.1 mg/(kg·d),7 d后停药,观察2组患者生命体征、格拉斯哥昏迷量表评分、觉醒时间、呼吸衰竭纠正时间,并进行统计学分析.参考格拉斯哥预后量表判断预后.结果 治疗组恢复良好10例(33.3%),死亡7例(23.3%),觉醒时间为(7.6±4.5)d,呼吸衰竭纠正时间为(6.6±3.7)d;对照组恢复良好7例(21.9%),死亡12例(37.5%),觉醒时间为(10.4±4.72)d,呼吸衰竭纠正时间为(9.9±4.1)d,2组差异均有统计学意义(P<0.05或P<0.01).结论 早期使用纳洛酮可降低急性重型颅脑损伤的致残率、病死率,减轻脑水肿,促使脑神经功能恢复,改善生活质量.     

阿片肽与缺血性脑损伤

阿片肽及其受体系统在缺血性脑损伤的病理生理发展过程中具有非常重要的作用。其在缺血性脑损伤中的作用尚存争议，本文综述了阿片肽及其受体系统在缺血性脑损伤中的作用及其可能机制，有助于探索阿片肽在围术期的合理应用，为缺血性脑损伤防治研究提供新方向。     

预适应锻炼对急进高原新兵脑功能的保护作用

目的探讨预适应锻炼对新兵急进高原后脑功能的改善作用。方法120名新兵随机分为4组:对照组、面罩组、运动组和面罩复合运动组。在进入高原前,面罩复合运动组佩带低氧呼吸器小步快走10 min,休息5 min后重复进行,上、下午各进行4次,连续进行7 d;面罩组、运动组分别只佩带低氧呼吸器或单纯运动。在空运进入高原后,比较进高原前、后的神经行为核心测试组合系统指标的改变,并对急性高原反应症状进行分析。结果使用低氧呼吸器复合小步快走5 min时动脉血氧饱和度可降到(80.5±5.7)%,达到预缺氧的目的。新兵进入3 658 m高原后,对照组、面罩组和运动组的数字跨度、目标追踪测试分值明显下降(P<0.05),而面罩复合运动组无明显改变(P>0.05);各组进藏前、后的简单反应时、数字译码和视觉保留均无显著性改变(P>0.05),手敏捷度则显著提高(P<0.05)。对照组、面罩组、运动组和面罩复合运动组的急性高原反应发病率分别为13.3%、20.0%、20.0%、3.3%。结论进入高原前,应用低氧呼吸器辅以适当运动,能改善急进高原人群的即时听觉记忆能力和手部运动的速度及准确性,避免部分脑功能的损害,并使急性高原反应发病率呈降低趋势。     

Cyclic analogues of Thr6-bradykinin,N8-Lys-bradykinin and endo-Lys8a-vespulakinin 1

Syntheses are described of the endo-Lys^8a-vespulakinin 1 and of cyclo-Thr⁶- and cyclo-N^ε-Lys-bradykinin. The linear peptides covering the entire sequences of endo-Lys^8a-VSK-1 and Thr⁶-BK, and the decapeptide containing all residues constituting Lys-BK, with a Arg-Lys peptide bond involving the ε-amino function of lysine, were prepared by the solid-phase procedure based on Fmoc chemistry. Cyclization was carried out by the diphenylphosphorazide method. The amino-terminal octapeptide sequence of vespulakinin 1, Fmoc-Thr(tBu)-Ala-Thr(tBu)-Thr(tBu)-Arg(Pmc)-Arg(Pmc)-Arg(Pmc)-Gly-OH, and its N^α-Boc-[(Gal β)Thr³, (Gal β)Thr⁴]-analogue, were used to prepare N^α-(1–8 VSK 1)-cyclo-N^ε-kallidin and N^α-[(Gal β)Thr³, (Gal β)Thr⁴, 1–8 VSK 1]-cyclo-N^ε-kallidin. Peptides and glycopeptides were characterized by amino-acid analysis, optical rotation, analytical HPLC and FAB-MS. Consistent with previous findings, preliminary pharmacological experiments on smooth muscle preparations showed that the cyclic, or partially cyclic, analogues were significatively less potent than the linear ones. © Munksgaard 1995.     

论现代医院技术创新

创新是医院发展主题,本文采用综合分析、收集资料、对比方法,对技术创新内容、技术创新原则、技术创新趋势进行了较详细的分析研究.     

Antibody reactivity to a synthetic peptide (P62) of the Epstein-Barr nuclear antigen in sera of patients with X-linked lymphoproliferative syndrome

An enzyme-linked immunosorbent assay (ELISA) was used to measured IgG antiboody titers againt a synthetic peptide whose sequence was derived from the glycine-alanine repeating region of Epstein-Barr virus nuclear associated antigen 1 (EBNA-1). Antibody titers were determined in sera from 15 normal subjects, sera from 21 normal male siblings of X-linked lymphoproliferative syndrome (XLP) patients, from 20 XLP patients comprising a total of 42 samples, and ten samples before and ten samples after gamma-globulin therapy in ten patients with XLP. Data analysis demonstrated that while there are differences between the ELISA and ACIF, they appear to measure a similar response as demonstrated by their correlation coefficient (0.77) and the GMT to EBNA observed by both methods. No cross-reactivity of cytomegalovirus antibodies to the EBNA-1 peptide was observed by immunobv using adsorption against AD-169 infected MRC-5 cells.. However, non-specific binding was observed if samples were not pre-incubated in a 10% goat serum PBS-Tween 20 solution. This pre-treatment removed the non-specific binding that falsely elevated GMT in approximately 15% of both normal and XLP samples in ELISA. The ELISA system appears to be a sensitive, reproducible and objective test that may be useful for assessing the antibody responses of patients to the EBNA-1 protein.