Current perspectives on bovine spongiform encephalopathy and variant Creutzfeldt–Jakob disease

Bovine spongiform encephalopathy (BSE) clearly originated in the UK, where there have now been more than 180 000 cases. However, through the exportation of cattle and cattle-feed additives from the UK, BSE also became established to a lesser extent in other European countries. There is current concern that BSE might have been distributed more widely as a result of the exportation of cattle or BSE-infected feed or foodstuff not only from the UK but also from other European countries that later became affected. It is now recognized that the transmissible agent that causes BSE also causes a new variant form of Creutzfeldt–Jakob disease (vCJD) in humans, and the evidence for this is presented. This probably resulted from dietary exposure to the bovine agent, and the potential role of mechanically recovered meat is discussed. There is a brief discussion on the controversial issue of the nature of the causal agents of diseases like BSE and vCJD. Whether or not sheep or goats could have become infected with BSE, and whether they represent a human health hazard, is also debated. Finally, the question of the control of BSE, and consequently vCJD, is discussed with regard to the rigorous application of the relevant regulations.     

Brain mapping analysis in patients with hepatic encephalopathy

Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients.     

脑干听觉诱发电位、CT在新生儿缺氧缺血性脑病中的诊断价值

目的:应用脑干听觉诱发电位(BAEP)结合CT为诊断新生儿缺氧缺血性脑病(HIE)及分度提供科学诊断依据。方法:采用ZABR—200型脑干反应测听仪及西德SomatomDR型高分辨全身扫描机对30例HIE患儿进行检测和扫描。结果:BAEP:正常4例(13.3％),异常26例(86.7％),CT:轻度异常8例,中度异常14例,重度异常8例。结论:本研究CT所示脑损伤程度与临床表现程度有密切关系,BAEP检查敏感性高,影响因素小,结果准确可靠,对诊断HIE,预测和评价预后,指导治疗均有一定的价值。     

新生儿缺氧缺血性脑病血浆ET和CGRP测定及临床意义

目的:探讨新生儿缺氧缺血性脑病患者血浆内皮素(ET)和降钙素基因相关肽(CGRP)水平的变化及临床意义.方法:应用放射免疫分析检测了符合诊断标准的观察组缺氧缺血性脑病新生儿68例,及对照组同期健康新生儿30例血浆中ET和CGRP水平,并做了比较.结果:观察组血浆ET水平显著的高于对照组,而CGRP水平显著的低于对照组.结论:新生儿缺氧缺血性脑病的发生发展与ET和CGRP水平的变化密切相关.     

Age-Related Changes in Ceruloplasmin Content in W/SSM Rats

We studied enzyme systems (lactate dehydrogenase) of mitochondria in cerebral nerve cells in experimental encephalopathy developing after thermal injury. In animals receiving neuromedin at the early terms after injury, the ratio of forward to reverse lactate dehydrogenase reactions significantly increased over the first day after injury and returned to normal on day 7. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 145, No. 6, pp. 626–627, June, 2008     

Early induction of neuronal lipocalin-type prostaglandin D synthase after hypoxic-ischemic injury in developing brains

Lipocalin-type prostaglandin (PG) D synthase (L-PGDS) is up-regulated in oligodendrocytes (OLs) in mouse models for genetic neurological disorders including globoid cell leukodystrophy (twitcher) and GM₁ and GM₂ gangliosidoses and in the brain of patients with multiple sclerosis. Since L-PGDS-deficient twitcher mice undergo extensive neuronal death, we concluded that L-PGDS functions protectively against neuronal degeneration. In this study, we investigated whether L-PGDS is also up-regulated in acute and massive brain injury resulting from neonatal hypoxic-ischemic encephalopathy (HIE). Analysis of brains from human neonates who had died from HIE disclosed that the surviving neurons in the infarcted lesions expressed L-PGDS. Mouse models for neonatal HIE were made on postnatal day (PND) 7. Global infarction in the ipsilateral hemisphere was evident at 24 h after reoxygenation in this model. Intense L-PGDS immunoreactivity was already observed at 10 min after reoxygenation in apparently normal neurons in the cortex, and thereafter, in neurons adjacent to the infarcted area. Quantitative RT-PCR revealed that the L-PGDS mRNA level of the infarcted hemisphere was 33-fold higher than that of the sham-operated mouse brains at 1 h after reoxygenation and that it decreased to the normal level by 24 h thereafter. Furthermore, in both human and mouse brains, many of L-PGDS-positive cells were also immunoreactive for p53; and some of these expressed cleaved caspase-3. The expression of L-PGDS in degenerating neurons implies that L-PGDS functions as an early stress protein to protect against neuronal death in the HIE brain.     

Case report: human herpesvirus 7 associated fatal encephalitis in a peripheral blood stem cell transplant recipient

Previous studies have suggested a neuroinvasive and neuropersistent potential of human herpesvirus 7 (HHV-7). In this report, a case of fatal encephalitis is described and its association with HHV-7 infection is discussed. An 8-year-old girl received a peripheral blood stem cell transplant for relapsed acute lymphoblastic leukaemia. The post-transplant period was uneventful and a course of intrathecal chemotherapy was given on Day-30. On Day-41, she developed acute encephalopathy with diplopia and nystagmus. She ran a rapid downhill course and succumbed despite antiviral treatment. The only positive pathological finding was the multiple microscopic foci of haemorrhage associated with neuronal degeneration detected in the brain stem. All microbiological investigations were negative, except for the presence of HHV-7 DNA in cerebrospinal fluid and brain stem tissue samples.     

长时程脑电监测对评估HIE预后的价值

目的:探讨脑电图(EEG)长时程监测对新生儿缺氧缺血性脑病(HIE)预后的临床价值。方法:对在我院高危儿室住院的52例HIE的患儿进行12～24 h的EEG监测,将其脑电信息储存,采用(日)福山幸夫"新生儿异常EEG"诊断标准进行回放分析。并随访35例患儿,对预后进行评估。结果:52例患儿中,35例表现为不同程度的背景脑电活动降低,异常率占67%,且临床为中、重型HIE患儿的EEG异常率(100%),明显高于轻型HIE患儿的异常率(39%)(P<0.01)。EEG表现为中、高度背景脑电活动降低者,留有后遗症的几率(8/24,33%)高于轻型EEG背景活动降低者的几率(2/28,7%)(P<0.05)。在出生>1周后的新生儿。EEG仍表现为中、高度背景脑电活动降低的患儿,留有癫癎、脑瘫的几率(11例均有后遗症)明显高于出生后1周内背景脑电活动降低患儿的几率(4/13,31%) (P<0.01)。结论:EEG表现为轻度背景脑电活动降低者,预后良好,中度背景脑电活动降低者预后不良,高度背景脑电活动降低者预后极差。因此长时程脑电监测对新生儿HIE诊断及预后的评估具有重要意义。     

Neuropathology of the Central Nervous System in Acquired Immune Deficiency Syndrome (AIDS) in Japan

The neuropathologiesl features of the central nervous system in IS autopsy cases of Japanese male with AIDS were reported. Nine patients had various histological changes including a variety of opportunistic infections in six patients (40%), primary malignant lymphoma of the brain in two (13%), AIDS encephalopathy in four (27%) and vacuolar myelopathy in one (7%). Usually, these pathological changes were present concomitantly. AIDS encephalopathy was characterized by infiltration of mono and multinucleated cells and myelin pallor with astrogliosis located predominantly in the cerebral white matter and subcortical gray matter. Furthermore, unevenly distributed neuronal loss of the cerebral cortex was apparent in one case. Diffuse astrocytosis of the gray matter out of proportion to neuronal loss was also an outstanding finding in another case. The present study suggested that not only the white matter changes but also gray matter alterations might be the morphological substrates of AIDS encephalopathy.     

P300等诱发电位对亚临床肝性脑病早期诊断的意义

目的:观察事件相关电位P_(300)、体感诱发电位、视觉诱发电位和脑干听觉诱发电位在亚临床肝性脑病诊断中的意义。方法:50例亚临床肝性脑病患者进行了心理测验,并做了头颅CT和视觉诱发电位、体感诱发电位、脑干听觉诱发电位和事件相关电位检查,30例正常人做为对照组。结果:亚临床肝性脑病的心理测验,韦氏法智力低下率为76％,视觉诱发电位异常率为13％,脑干听觉诱发电位异常率为20％,体感诱发电位异常率为40％,事件相关电位异常率为71％,正常对照组四种诱发电位的正常率是100％。头颅CT结果与亚临床肝性脑病无关。结论:视觉诱发电位、体感诱发电位、脑干听觉诱发电位和事件相关电位在亚临床肝性脑病中是异常的。事件相关电位更为敏感,对亚临床肝性脑病的早期诊断有重要意义。