Nogo-A Expression in the Brain of Mice with Cerebral Malaria

Cerebral malaria (CM) is associated with a high rate of transient or persistent neurological sequelae. Nogo-A, a protein that is highly expressed in the endoplasmic reticulum (ER) of the mammalian central nervous system (CNS), is involved in neuronal regeneration and synaptic plasticity in the injured CNS. The current study investigates the role of Nogo-A in the course of experimental CM. C57BL/6J mice were infected with Plasmodium berghei ANKA blood stages. Brain homogenates of mice with different clinical severity levels of CM, infected animals without CM and control animals were analyzed for Nogo-A up-regulation by Western blotting and immunohistochemistry. Brain regions with Nogo-A upregulation were evaluated by transmission electron microscopy. Densitometric analysis of Western blots yielded a statistically significant upregulation of Nogo-A in mice showing moderate to severe CM. The number of neurons and oligodendrocytes positive for Nogo-A did not differ significantly between the studied groups. However, mice with severe CM showed a significantly higher number of cells with intense Nogo-A staining in the brain stem. In this region ultrastructural alterations of the ER were regularly observed. Nogo-A is upregulated during the early course of experimental CM. In the brain stem of severely affected animals increased Nogo-A expression and ultrastructural changes of the ER were observed. These data indicate a role of Nogo-A in neuronal stress response during experimental CM

Unresponsive wakefulness syndrome: a new name for the vegetative state or apallic syndrome

BACKGROUND: Some patients awaken from coma (that is, open the eyes) but remain unresponsive (that is, only showing reflex movements without response to command). This syndrome has been coined vegetative state. We here present a new name for this challenging neurological condition: unresponsive wakefulness syndrome (abbreviated UWS). DISCUSSION: Many clinicians feel uncomfortable when referring to patients as vegetative. Indeed, to most of the lay public and media vegetative state has a pejorative connotation and seems inappropriately to refer to these patients as being vegetable-like. Some political and religious groups have hence felt the need to emphasize these vulnerable patients' rights as human beings. Moreover, since its first description over 35 years ago, an increasing number of functional neuroimaging and cognitive evoked potential studies have shown that physicians should be cautious to make strong claims about awareness in some patients without behavioral responses to command. Given these concerns regarding the negative associations intrinsic to the term vegetative state as well as the diagnostic errors and their potential effect on the treatment and care for these patients (who sometimes never recover behavioral signs of consciousness but often recover to what was recently coined a minimally conscious state) we here propose to replace the name. CONCLUSION: Since after 35 years the medical community has been unsuccessful in changing the pejorative image associated with the words vegetative state, we think it would be better to change the term itself. We here offer physicians the possibility to refer to this condition as unresponsive wakefulness syndrome or UWS. As this neutral descriptive term indicates, it refers to patients showing a number of clinical signs (hence syndrome) of unresponsiveness (that is, without response to commands) in the presence of wakefulness (that is, eye opening)

Improving the clinical assessment of consciousness with advances in electrophysiological and neuroimaging techniques

In clinical neurology, a comprehensive understanding of consciousness has been regarded as an abstract concept - best left to philosophers. However, times are changing and the need to clinically assess consciousness is increasingly becoming a real-world, practical challenge. Current methods for evaluating altered levels of consciousness are highly reliant on either behavioural measures or anatomical imaging. While these methods have some utility, estimates of misdiagnosis are worrisome (as high as 43%) - clearly this is a major clinical problem. The solution must involve objective, physiologically based measures that do not rely on behaviour. This paper reviews recent advances in physiologically based measures that enable better evaluation of consciousness states (coma, vegetative state, minimally conscious state, and locked in syndrome). Based on the evidence to-date, electroencephalographic and neuroimaging based assessments of consciousness provide valuable information for evaluation of residual function, formation of differential diagnoses, and estimation of prognosis

A szennyező nehézfémsók hatása a talajbaktériumok mennyiségére és a talajlégzésre in vitro körülmények között

Az ólom- (Pb2+), a kobalt- (Co2+) és a kadmium- (Cd2+) ionok hatását vizsgáltuk Gödöllőről származó, mezőgazdasági művelés alatt álló (továbbiakban: művelt) és nem művelt barna erdőtalajban élő aerob talajbaktériumok aktivitására. Az üvegedényekbe töltött talajmintákat üvegházban, 28 °C-on inkubáltuk egy, három és hat hétig. A talajban élő baktériumok anyagcseréjét C, N és P hozzáadásával aktiváltuk, a tápanyagokat nátrium-nitrát, kálium-foszfát és glükóz formájában adtuk a talajhoz a szubsztrát-indukált légzés vizsgálatára (SIR: substrate induced respiration). Meghatároztuk az összes mobilizálható nehézfém frakció, az összes aerob baktérium csíraszám és a fejlődött CO2 mennyiségének változását az inkubációs idő alatt. A vizsgált nehézfémek vegyületei egy héten belül nagymértékben immobilizálódtak, majd további inkubáció után fokozatosan újramobilizálódtak. A nehézfémionok adagolása csökkentette a talaj teljes aerob baktérium számát, valamint fiziológiai aktivitását. Az aerob baktérium-populációk általában a CO2- termeléshez hasonlóan csökkentek a vizsgált fémionok toxikus hatására. A talajminták biológiai aktivitásában bekövetkezett gátlások már három hét után is érvényesültek, de igazán jelentős hatásokat a 6 hetes inkubációs periódus végén tapasztaltunk. A különböző inkubációs szakaszokban az Pb2+ csökkentette a legkisebb mértékben a művelt és a nem művelt talajok CO2-kibocsátását. A gázkibocsátást a Cd2+-ionok gátolták a leginkább, de Co2+-ionok jelenlétében is érzékelhető volt határozott csökkenés