The effect of bacterial melanin on electrical activity of neurons of the substantia nigra under conditions of GABA generation

The changes in spike activity of single neurons of the compact part of the substantia nigra, evoked by nucleus caudatus stimulation under conditions of long-term registration of the single and multiple, isolated and combined actions of GABA, GABA-amide, glutamine, and ethanolamine-O-sulfate (EOS) were studied in albino rats. Inhibition of poststimulus activity under GABA action was recorded and the inhibitory effect of GABA-amide was revealed. Primary excitatory and subsequent inhibitory effects of glutamine in combination with EOS were shown. The subsequent administration of bacterial melanin, synthesized by a mutant culture of Bacillus thuringiensis (BT-M) evoked a clear-cut and prolonged excitatory reaction during all the combined actions of GABA, GABA-amide, glutamine, and EOS. Preliminary administration of BT-M abolished the inhibitory poststimulus effects of GABA, GABA-amide, and EOS, as well as glutamine-induced excitation.     

重症急性胰腺炎时肠屏障破坏的机制及防治

众多因素参与了重症急性胰腺炎时肠屏障破坏的发生、发展，随之而来的菌群移位及内毒素血症又加重了肠屏障破坏，导致严重不良预后。本文综合了肠屏障受损的可能原因，同时针对发病原因提出了相应防治对策。     

参附注射液对实验性急性坏死性胰腺炎肠道细菌移位的影响

目的：研究参附注射液对实验性急性坏死性胰腺炎（ANP）时肠道细菌移位的影响。方法：ANP大鼠制模方法采用胰腺被膜下注射牛磺胆酸钠。假手术组、对照组经皮下注射生理盐水，实验组同法给予等量参附注射液。取标本（下腔静脉血、腹水、肠系膜淋巴结及大肠内容物）进行细菌培养，计数菌落数及鉴定细菌种类。结果：标本中生长的细菌与大肠内容物培养细菌种类相同，实验组标本的菌落数少于对照组（P〈0.01）。结论：实验性ANP大鼠合并感染的细菌来源于肠道，参附注射液可以减少肠道细菌移位。     

冰片开放血-脑脊液屏障对实验性细菌性脑膜炎治疗影响的研究

目的 探讨冰片开放血-脑脊液屏障（BCB）对实验性细菌性脑膜炎治疗的影响。方法 采用日本大耳白兔作为实验动物，随机分为对照组、冰片组和脑膜炎组。经枕大池注入肺炎球菌悬液建立脑膜炎模型，以冰片作为开放BCB的制剂。以连续静脉注射丙戊酸钠后不同时间点的脑脊液中丙戊酸钠浓度变化作为判断BCB通透性的指标；硝酸镧示踪法观察脑组织表现作为BCB通透性的形态指标。给予脑膜炎动物头孢吡肟或冰片＋头孢吡肟治疗，记录动物存亡情况；取脑脊液（CSF）进行细胞计数及生化检查。取脑组织作常规病理染色，以观察冰片开放BCB对实验性细菌性脑膜炎治疗的影响。结果 给药后对照组CSF中丙戊酸钠浓度基本保持稳定，冰片组CSF中丙戊酸钠浓度于给药后0．5h时即高于对照组并逐渐上升，至6h时达高峰，然后开始下降，14h时浓度仍高于对照组。脑组织超微结构显示，对照组无硝酸镧颗粒通过BCB，脑膜炎组硝酸镧颗粒分布于毛细血管基底膜外，冰片组弥漫性分布于神经细胞间隙和轴突周围。给予头孢吡肟治疗后，脑膜炎＋冰片组动物存活率（9／12，75％）明显高于脑膜炎组（6／18，66．7％）（P〈0．05），但两组间CSF细胞数及蛋白、葡萄糖水平差异无统计学意义。近皮层脑组织HE染色显示，脑膜炎组可见脑组织大量炎症细胞渗出和软化坏死灶,血管“套袖”现象明显，而脑膜炎＋冰片组脑组织内炎症细胞渗出较少，无血管“套袖”现象，无明显坏死软化灶。结论 冰片确实能明显增加BCB的通透性并具有可逆性特点，抗生素联合冰片能改善实验性细菌性脑膜炎治疗效果，为细菌性脑膜炎的治疗提供了新的思路。     

原发性前列腺印戒细胞癌(1例报告并文献复习)

目的探讨原发性前列腺印戒细胞癌的临床特征。方法回顾性分析1例原发性前列腺印戒细胞癌患者的临床资料,并结合文献进行复习讨论。结果患者前列腺穿刺活检病理报告为前列腺印戒细胞癌,免疫组织化学检查示PSA( ),PAS、CEA、LCA、CKH(-),行双侧睾丸切除术和氟他胺治疗,术后1月死于肺部转移。结论原发性前列腺印戒细胞癌来自前列腺腺泡上皮,确诊依靠病理组织学和免疫组化检查。临床罕见,恶性程度高,预后较差。     

Effects of low-dose transdermal scopolamine on autonomic cardiovascular control in healthy young subjects

We studied how posture influences the effects of transdermal scopolamine on autonomic cardiovascular regulation in a randomized, double-blind, placebo-controlled crossover study of 10 healthy young volunteers. We recorded the electrocardiogram and auscultatory sphygmomanometric and continuous non-invasive finger arterial pressure (Finapres device) to obtain signals for the beat-by-beat R–R interval and systolic, mean and diastolic pressures. R–R interval and arterial pressure variabilities were characterized by power spectral analysis. Scopolamine increased the mean R–R intervals and reduced arterial pressure in both the supine and the standing positions, but did not affect blood pressure variability. Scopolamine increased the total variability of R–R interval and its mid- (0·07–0·15 Hz) and high- (0·15–0·40 Hz) frequency band power in the standing position during controlled breathing at 0·25 Hz. In the supine position, scopolamine did not affect R–R interval variability. In the deep breathing test, scopolamine increased the maximal expiratory–inspiratory R–R interval ratio. This study showed that low-dose scopolamine increases vagal cardiac inhibition in both supine and standing positions in healthy volunteers. However, scopolamine increases heart rate variability only in the standing position during partial vagal withdrawal. The study also demonstrates that transdermal scopolamine decreases blood pressure in healthy young subjects.     

The role of α2-adrenoceptors of the medullary lateral reticular nucleus in spinal antinociception in rats

We attempted to find out the role of α₂-adrenoceptors of the medullary lateral reticular nucleus (LRN) in antinociception in rats. Spinal antinociception was evaluated using the tail-flick test, and supraspinal antinociception using the hotplate test. Antinociceptive effects were determined following local electric stimulation of the LRN, and following microinjections of medetomidine (an α₂-adrenoceptor agonist; 1–10 μg), atipamezole (an α₂-adrenoceptor antagonist; 20 μg) or lidocaine (4%) into the LRN. The experiments were performed using intact and spinalized Hannover-Wistar rats with a unilateral chronic guide cannula. Electric stimulation of the LRN as well as of the periaqueductal gray produced a significant spinal antinociceptive effect in intact rats. Medetomidine (1–10 μg), when microinjected into the LRN, produced no significant antinociceptive effect in the tail-flick test in intact rats. However, following spinalization, medetomidine in the LRN (10 μg) produced a significant atipamezole-reversible antinociceptive effect in the tail-flick test in the hot-plate test, medetomidine (10 μg) in the LRN produced a significant atipamezole-reversible increase of the paw-lick latency in intact rats. Microinjection of atipamezole (20 μg) or lidocaine alone into the LRN produced no significant effects in the tail-flick test. The results are in line with the previous evidence indicating brat the LRN and the adjacent ventrolateral medulla is involved in descending inhibition of spinal nocifensive responses. However, α₂-adrenoceptors in the LRN do not mediate spinal antinociception but, on the contrary, their activation counteracts antinociception at the spinal cord level. The spinal aninociceptive effect of supraspinally administered medetomidine in spinalized rats can be explained by a spread of the drug (e.g., via circulation) which then directly activates α₂-adrenoceptors at the spinal cord level.     

Effects of N-acetylcysteine on bacterial clearance

Abstract. The aim of this study was to investigate whether the oxygen radical scavenger N -acetylcysteine ( N -AC) impairs bacterial clearance, thus predisposing the host to increased risk of disease. Blood clearance of Escherichia coli and organ colonization were investigated in anaesthetized rabbits after pretreatment with N -AC (250 mg kg^-1 body weight, n = 16) and in sham-operated animals ( n = 12). To enable quantification of the clearance process, defined numbers of exogenous E. coli [1.3 times 108 colony-forming units (CFUs)] were injected intravenously. Parameters monitored were kinetics of bacterial elimination from the blood, and polymorphonuclear leucocyte (PMN) oxidative burst activity. Samples of liver, kidney, spleen and lung were collected for bacterial counts. Compared with controls, pretreatment with N -AC resulted in delayed bacterial elimination from blood and higher organ colonization with increased numbers of E. coli in liver, lung and kidney ( P < 0.05). N -AC treatment was associated with a suppressed PMN oxidative burst activity. Impaired bacterial clearance and enhanced organ colonization in N -AC-treated animals correlated with reduced oxidative burst activity, suggesting impaired granulocyte-dependent bacterial killing due to N -AC application.     

环丙沙星滴眼液治疗急性细菌性结膜炎的临床疗效

本文对１０９例（１３０眼）临床诊断急性细菌性结膜炎，应用０．３％环丙沙星（ＣＰＬＸ）滴眼液（７０眼）和０．３％诺氟沙星（ＮＦＬＸ）滴眼液（６０眼），作了双盲随机治疗研究各１个星期。治愈率ＣＰＬＸ组６２．８６％、ＮＦＬＸ组４５％，显效ＣＰＬＸ组３２．８５％，ＮＦＬＸ组４６．６６％。治疗后细菌清除率ＣＰＬＸ组９４．７８％、ＮＦＬＸ组９２．９５％。两种抗菌素对革兰氏阳性和阴性菌的作用相似，治疗中无一例有任何副反应或局部不能耐受。ＣＰＬＸ对治疗外眼部细菌感染如急性细菌性结膜炎为一安全有效的药物，其临床疗效与对微生物作用在本组试验中与ＮＦＬＸ相似。