Intracranial actinomycosis in juvenile patients Case report and review of the literature

A case of actinomycotic brain infection in a juvenile patient is described. Cases of actinomycosis affecting the head and neck are rare, particularly in juvenile patients. In this case complete resolution of the infection was achieved by means of surgical treatment and prolonged antibiotic therapy. The authors emphasize the importance of a combined approach for treatment of this unusual brain infection and stress the difficulties involved in the diagnosis of this pathology. Received: 3 November 1997     

肺癌脑转移83例临床分析

我所内科１９８８￣１９９３年收治肺癌患者１００６例，脑转移８３例，占８．２５％，由于治疗方法不同，其预后极其不同。手术切除加放疗化疗与单纯放疗化疗的生存率有显著性差异（Ｐ〈０．０５），放疗化疗综合组疗效预后好于单一治疗组（Ｐ〈０．０５）。因此在肺癌确诊后应常规作脑影像学检查，可早期诊断，这是提高疗效和生存捏的重要因素。     

热休克反应对大鼠感染性脑水肿脑组织诱生型一氧化氮合酶mRNA表达的影响

:探讨热休克反应 (HSR)对百日咳杆菌所致的大鼠感染性脑水肿诱生型一氧化氮合酶 (iNOS)mRNA表达的影响。方法 :从大鼠左侧颈内动脉注入百日咳菌液制备感染性脑水肿 (感脑 )模型 ,采用组织细胞原位杂交技术检测脑组织iNOSmRNA的表达。结果 :生理盐水组、4h感脑组及 4h热休克处理组均未见iNOSmRNA表达 ,8h ,2 4h时感染性脑水肿组均有明显的杂交信号 ,以 2 4h更为明显 ;而 8h ,2 4h热休克处理组仅有少数细胞有阳性信号。结论 :热休克反应对感染性脑水肿的保护作用可能与抑制iNOSmRNA的表达有关     

The value of different methods of treatment of brain abscess in the CT era

Summary 67 cases of brain abscess were analyzed retrospectively. As 2 comatose patients died on admission before any treatment was started, the results are based on 65 treated patients. Different methods of treatment included: total removal in 36 patients, drainage in 14, aspiration in 6 and conservative treatment in 9. Management mortality was 18,5% and was almost not dependent on the method of treatment (except aspiration) being lowest in the drainage group. The mortality was significantly higher in patients with serious impairment of consciousness on admission.Follow-up examination after 1 to 11 years was performed in 47 out of 53 discharged patients and revealed in 25 of them (53%) full recovery. 10 additional cases (21%) are independent. The best early and long term results were obtained in patients by drainage and medical treatment.Chronic epilepsy developed in 34% of patients with supratentorial lesions. The risk of epilepsy was lowest in the group of patients treated by drainage.The authors present the opinion that removal of brain abscess is necessary only in exceptional cases.     

Flip side of synaptic plasticity: Long-term depression mechanisms in the hippocampus

There is growing interest in the phenomenon of long-term depression (LTD) of synaptic efficacy that, together with long-term potentiation (LTP), is a putative information storage mechanism in mammalian brain. In neural network models, multiple learning rules have been used for LTD induction. Similarly, in neurophysiological studies of hippocampal synaptic plasticity, a variety of activity patterns have been effective at inducing LTD, although experimental paradigms are still being optimized. In this review the authors summarize the major experimental paradigms and compare what is known about the mechanisms of LTD induction. Although all paradigms appear to initiate a cascade of events leading to an elevated level of Ca²⁺ postsynaptically, the extent to which these paradigms involve common expression mechanisms has not yet been tested. The authors discuss several critical experiments that would address this latter issue. Numerous questions about the properties and mechanisms of LTD(s) in the hippocampus remain to be answered, but it is clear that LTD has finally arrived, and will soon be attracting attention equal to its flip side, LTP. © 1994 Wiley-Liss, Inc.     

Benzodiazepine concentrations in brain directly reflect receptor occupancy: studies of diazepam,lorazepam, and oxazepam

Groups of male CF-1 mice received 3 and 10 µmol/kg diazepam, lorazepam, and oxazepam intravenously. Between 1 min and 24 h after injection, benzodiazepine concentrations were determined by gas chromatography (GLC) in plasma and in one brain hemisphere; in the other hemisphere, ex vivo benzodiazepine receptor occupancy was measured using³H-flunitrazepam displacement. Based on GLC data, diazepam entered brain rapidly, and was also cleared rapidly, yielding desmethyldiazepam and oxazepam as metabolites in plasma and brain. However, lorazepam and oxazepam entered brain slowly, with brain:plasma equilibrium achieved at 30–60 min; thereafter, the drugs were eliminated from plasma and brain in parallel. The time course and extent of ex vivo occupancy were highly consistent with GLC data (for diazepam, GLC levels were expressed as the sum of diazepam, desmethyldiazepam, and oxazepam, with metabolite concentrations, normalized for molecular weight and for in vitro benzodiazepine receptor affinity.) Between-method correlations were 0.95 or higher. Thus benzodiazepine receptor occupancy is highly dependent on benzodiazepine concentrations in brain. Differences in the time-course of onset and duration of pharmacologic activity between the highly lipophilic benzodiazepine diazepam and the less lipophilic hydroxylated derivatives lorazepam and oxazepam are largely explained by differences in systemic kinetics and in the rate of uptake into brain.Supported in part by grants MH-34223, DA-05258, and AG-00106 from the United States Public Health Service     

白血病抑制因子反义寡核苷酸对髓母细胞体外生长的抑制作用

为进一步认识白血病抑制因子（LIF）对人髓母细胞瘤生长的生物学作用，我们使用LIF反义寡核苷酸，在髓母细胞内特异性阻断LIF基因表达并观察它对靶细胞的生物学效应。结果发现，被处理细胞的LIF表达降低至RT／PCR检出的阈值之下，抗LIF的免疫组织化学染色亦呈阴性，同时，这些细胞的生长速度明显减缓。相反，用与反义寡核苷酸互补的正义序列处理的细胞无论在基因表达／产生，还是在生长速度方面，均和正常培养细胞的细胞相似，本研究从而提示了一条以LIF为对象的髓母细胞瘤以及其它LIF生长依赖性肿瘤的基因和免疫治疗途径。     

老年人脑皮质下斑点状病灶的MRI病理基础研究

本文对29例脑标本行 MRI-病理对照研究,其中18例脑标本 MRI 检查阳性,发现脑皮质下斑点状病灶(Subcortical Patchy Lesions,SPLs)95个。该病灶分两大类:第一类(64个)位于脑皮层下白质、基底核、小脑和脑干,其病理基础主要为血管周围间隙扩大(83%),小梗塞灶(11%),其他还有小动、静脉畸形(AVM),脱髓鞘灶和胶质增生灶;第二类(31个)位于侧脑室周围白质内,其病理基础为局部组织结构疏松呈空泡状,病灶相应部位的室管膜大片脱落。     

NO在体外循环中脑损伤作用机制的研究进展

一氧化氮及一氧化氮合酶在体外循环导致的脑损伤中具有重要作用,它可以通过扩张血管/抑制血小板聚集与黏附/减少细胞凋亡等对脑组织产生保护作用。一氧化氮的临床应用仍需对其作用机制作进一步深入研究。     

亚低温对大鼠脑损伤后脑组织炎性反应的影响

目的探讨颅脑外伤后早期应用亚低温治疗对脑组织炎性反应的影响。方法采用Feeney自由落体改良模型,设定对照组、颅脑外伤模型组及亚低温组,每组再根据伤后不同生存时间随分为3个亚组。取伤灶脑组织检测髓过氧化酶(MPO)活性,做细胞间黏附子-1(ICAM-1)免疫组化染色,光镜下计数ICAM-1阳性血管数。结果亚低温组各时间点伤灶区ICAM-1阳性血管数明显低于颅脑外伤模型相应时间点(P<0.01)。亚低温组各时间点MPO活性均明显低于颅脑外伤模型组相应时间点(P<0.01)。结论亚低温治疗能明显减少伤灶区白细胞浸润及ICAM-1的表达,有助于改善颅脑外伤后脑组织炎性反应引起的继发性脑损伤。