外伤性视神经病变的临床治疗分析

目的　探讨大剂量甲基强的松龙冲击疗法治疗外伤性视神经病变的疗效。方法　 2 0例 (2 0只眼 )外伤性视神经病变患者为治疗组 ,应用大剂量甲基强的松龙冲击治疗 ,另 2 0例 (2 0只眼 )外伤性视神经病变患者为对照组 ,使用常规剂量的地塞米松治疗。两组均同时使用高渗剂、血管扩张剂、神经营养剂及 B族维生素治疗 ,对两组病例药物治疗的结果进行总结分析。结果　治疗组经治疗后视力开始恢复的时间早于对照组 ,治疗组的总有效率为 80 % ,对照组的总有效率为 6 0 % ,治疗组的疗效优于对照组 ,且治疗越早疗效越好。两组比较具有显著的统计学差异 (P <0 .0 5 )。结论　大剂量甲基强的松龙冲击疗法治疗外伤性视神经病变疗效显著 ,治疗方便 ,是较理想的治疗方法     

Assessment of hand-arm vibration exposure among traffic police motorcyclists

 The aims of this study were (1) to evaluate subjective symptoms in the hand-arm system of all traffic police motorcyclists of a city located in the central part of Japan and (2) to assess their hand-arm vibration exposure associated with traffic police motorcycle riding. The study population consisted of 119 motorcycling traffic policemen and 49 male controls. By means of a questionnaire, information on the occupational history and the presence of subjective symptoms in the hand-arm system of all subjects was obtained. Vibration was measured on the handlebars of the representative motorcycles and on the hands of the riders. The 4- and 8-h energy-equivalent frequency-weighted acceleration as well as the lifetime vibration dose were calculated for all police motorcyclists. The prevalence of finger blanching in the traffic police motorcyclists was 4.2%, but none of the controls had this symptom. The rates of finger numbness (19.3%), finger stiffness (16.0%), shoulder pain (13.4%), and shoulder stiffness (45.4%) were significantly higher among police motorcyclists as compared with controls. The root-mean-square (rms) frequency-weighted acceleration on the handlebars of police motorcycles was in the range of 2.2–4.9 m/s² rms. The computed 4- and 8-h energy-equivalent frequency-weighted acceleration values were 2.8– 4.5 and 2.0 –3.2 m/s² rms, respectively. A pattern of increasing percentage prevalence with increasing cumulative vibration dose was noticed. The subjects with a lifetime vibration dose of more than 20.1 m² h ³ s^-4 (ln scale) showed significantly higher prevalence rates for symptoms in the fingers and shoulders as compared with the control group. As occupational vibration exposure of traffic police motorcyclists might be considered a risk factor for the development of symptoms in the hand-arm system of the riders, its evaluation and control is needed for prevention methodology evolution. Received: 15 April 1996/Accepted: 8 November 1996     

异氟醚预处理脑保护作用的剂量-效应关系

目的　研究异氟醚预处理脑保护作用的剂量效应关系 .方法　 4 0只雄性 SD大鼠 ,随机分为 4组 :对照组 ,Iso1,Iso2和 Iso3组 (n=10 ) .对照组大鼠每日吸 4 L· min- 1 (970m L· L- 1 O2 ) O2 1h,连续 5 d.Iso1,Iso2和 Iso3组大鼠分别接受浓度为 7.5 ,15 .0和 2 2 .5 m L·L- 1 的异氟醚预处理 (异氟醚和 4 L· min- 1 O2 ) ,每日 1h,连续 5 d.最后 1次处理结束 2 4 h后 ,用右侧颈内动脉尼龙线线栓法制作大脑中动脉阻闭 (middle cerebral artery occlusion,MCAO)模型 .异氟醚预处理效果根据再灌注 2 4 h时的神经损害评分及脑梗死容积判定 .结果　 Iso2和 Iso3组大鼠神经功能障碍及脑梗死容积均与对照组及 Iso1组相比差异显著 (P<0 .0 5 ) .Iso3组大鼠神经功能障碍及脑梗死容积与 Iso2组相比差异显著 (P<0 .0 5 ) .结论　异氟醚预处理需达到一定浓度才能诱导脑缺血耐受 ,并存在一定的剂量效应关系     

Comparative studies on cytotoxic and genotoxic effects of two organic mercury compounds in lymphocytes and gastric mucosa cells of sprague-dawley rats

Human lymphocytes (HL) as well as lymphocytes (RL), hepatocytes (RH), and gastric mucosa cells (GM) of Sprague-Dawley rats were treated in vitro for 1 h with methylmercury chloride (MMC, 0.5–4 μg/ml) and dimethylmercury (DMM, 5–40 μg/ml). The cytotoxicity of the two organic mercury compounds was assessed by dye exclusion, and the extent of induced DNA fragmentation was measured with a single-cell microgel electrophoresis assay. Both MMC and DMM induced DNA damage and cytotoxicity in a dose-related manner in HL, RL, and GM. MMC was more effective in causing a significant increase in median DNA migration than DMM at doses yielding approximately the same degree of cytotoxicity. In rat hepatocytes the MMC-induced DNA damage was, however, lower than in the other cells. An analysis of repair kinetics following exposure to 2 μg/ml MMC was carried out in human lymphocytes obtained from an adult male donor. The bulk of DNA repair occurred 90 min after in vitro exposure, and it was about complete by 120 min following cessation of exposure. Finally, in order to have a basis for extrapolating to the human situation, in vivo studies were performed with Sprague-Dawley rats, also assessing the DNA damage and cytotoxicity in the lymphocytes and gastric mucosa cells. These in vivo results after oral exposure may be directly compared to the in vitro data obtained in the same cells. © 1993 Wiley-Liss, Inc.     

Activation of a Ca2+-dependent K+ current by the oncogenic receptor protein tyrosine kinase v-Fms in mouse fibroblasts

We investigated the effects of the receptor-coupled protein tyrosine kinase (RTK) v-Fms on the membrane current properties of NIH3T3 mouse fibroblasts. We found that v-Fms, the oncogenic variant of the macrophage colony-stimulating factor receptor c-Fms, activates a K⁺ current that is absent in control cells. The activation of the K⁺ current was Ca²⁺-dependent, voltage-independent, and was completely blocked by the K⁺ channel blockers charybdotoxin, margatoxin and iberiotoxin with IC₅₀ values of 3nM, 18 nM and 76nM, respectively. To identify signalling components that mediate the activation of this K⁺ current, NIH3T3 cells that express different mutants of the wildtype v-Fms receptor were examined. Mutation of the binding site for the Ras-GTPase-activating protein led to a complete abolishment of the K⁺ current. A reduction of 76% and 63%, respectively, was observed upon mutation of either of the two binding sites for the growth factor receptor binding protein 2. Mutation of the ATP binding lobe, which disrupts the protein tyrosine kinase activity of v-Fms, led to a 55% reduction of the K⁺ current. Treatment of wild-type v-Fms cells with Clostridium sordellii lethal toxin or a farnesyl protein transferase inhibitor, both known to inhibit the biological function of Ras, reduced the K⁺ current amplitude to 17% and 6% of the control value, respectively. This is the first report showing that an oncogenic RTK can modulate K⁺ channel activity. Our results indicate that this effect is dependent on the binding of certain Ras-regulating proteins to the v-Fms receptor and is not abolished by disruption of its intrinsic protein tyrosine kinase activity. Furthermore, our data suggest that Ras plays a key role for K⁺ channel activation by the oncogenic RTK v-Fms. Received: 19 November 1997 / Accepted: 21 January 1998     

A breathing lung phantom for 81mKr lung ventilation studies its use in dosimetry and quality control

The construction of a breathing lung phantom that can be used to measure the amount of radioactive gas in the lungs as well as to determine the absorbed dose is described. For a lung ventilation study that consists of 6 views of 300 kents each, an effective dose equivalent of 50 Sv was calculated. The phantom is also suitable for comparison of different generator systems.     

Analgesic dose-response relation in cervical epidural block

The relationship between the age and the spread of analgesia from different epidural anesthetic doses was examined by studying analgesic dose responses in cervical epidural analgesia. Two different anesthetic doses (5ml or 10ml) of 2% mepivacaine were injected into the cervical epidural space at a constant pressure (80mmHg) using an intravenous apparatus, and the spread of analgesia to pinprick was assessed. The significant correlation was found between the patients age and the number of spinal segments blocked (5ml:r = 0.8498, P < 0.01, 10ml:r = 0.5988, P < 0.01). The inverse linear relationship was found between the patients age and the segmental dose requirement (5ml:r = –0.6754, P < 0.01, 10ml:r = –0.5784, P < 0.01). Patients under 39 years of age showed a direct relationship between the dose injected and the number of spinal segments blocked, enabling prediction of the number of segments blocked with a given dose of local anesthetic. Doubling the epidural dose approximately doubled the number of spinal segments blocked. The analgesic dose-response relation in patients over 60 years of age differed from that in patients under 39 years of age and doubling the epidural dose did not double the number of spinal segments blocked. Progressively more extensive analgesia was obtained from a given dose of local anesthetic with advancing age. It was difficult to limit the extent of analgesia by injecting a smaller dose of local anaesthetic in the elderly.(Hirabayashi Y, Matsuda I, Inoue S et al.: Analgesic dose-response relation in cervical epidural block. J Anesth 2: 22–27, 1988)     

Pharmacokinetics and tolerance of a new penem antibiotic,FCE 22101, in healthy volunteers after a single intravenous dose

Summary The clinical tolerance and pharmacokinetics of FCE 22101 (sodium (5R, 6S)-6-[(1R)-hydroxyethyl]-2-carbamoyloxymethyl-2-penem-3-carboxylate), a new penem antibiotic, have been studied after giving a single i.v. dose of 4 mg·kg^–1 to ten healthy male volunteers. The pharmacokinetics was estimated according to a two-compartment open model. The peak plasma concentration (C_max) was 15.5 (1.08) µg·ml^–1, mean (SEM). FCE 22101 was rapidly cleared from the systemic circulation [ =44.2 (4.2) min; CL=7.21 (0.47) ml·kg^–1·min^–1]. The mean apparent volume of distribution at steady-state was 246 (16.9) ml·kg^–1. The mean residence time relative to the 10 min infusion was 39.4 (1.5)min. Urinary recovery of FCE 22101 showed wide inter-subject variation, ranging from 10.2 to 53.6% of the dose. No subject complained of adverse effects.     

Lactic dehydrogenase virus (LDV) impairs the antigen-presenting capacity of macrophages yet fails to affect their phagocytic activity

The effect of acute infection of mice with lactic dehydrogenase virus (LDV) on two major functions of peritoneal macrophages was tested. Using a macrophage-dependent T cell proliferative assay to test the antigen-presenting capacity of LDV-infected macrophages we found that LDV impairs the capacity of antigen-presenting cells to trigger memory T lymphocytes. Endocytosis of antigen by LDV-infected macrophages was similar to that of uninfected cells. In addition, the proportion of intracellular antigen versus membrane-bound antigen in LDV-infected cells were similar to that observed in uninfected mice. It appears therefore, that the impaired immunogenic effect of LDV-infected macrophages results from reduced immunogenicity of the membrane-bound antigen.Testing the phagocytic activity of peritoneal macrophages we found that the uptake of radiolabeled antibody-coated sheep erythrocytes or bacteria (E. coli) by infected cells was similar to that by uninfected macrophages. In addition, LDV failed to affect the ability of peritoneal macrophages in a nitroblue tetrazolium reduction reaction which serves as an alternative parameter for measuring phagocytic activity. Our results support the assumption that LDV, which probably propagates in the cells of the reticuloendothelial system, impairs some of the immunogenic functions of macrophages and thereby affects macrophage-dependent immune responses.     

The immune response of healthy adults to a reduced dose of hepatitis B vaccine

Three hundred thirty-six medical personnel from hemodialysis centers were treated with three doses, 20 μg each, of the Merck hepatitis B vaccine (at 0, 1, and 6 months). Within 1 month after the first injection, 41% converted to anti-HBs positivity; after the second injection the conversion rate rose to 80–90%; and after the booster, to 96–98%. The later rate remained unchanged during the 18-month follow-up period. Only 2.8% of those vaccinated did not respond to the vaccine. The patterns of immune responses to 20-μg doses were found to be exactly the same as to 40-μg doses. It is suggested that reduced doses of vaccine should be as efficacious as the larger ones.