disturbances in brain charges

Intensive exposures to natural and artificial sources of infrasonic acoustic shock (tectonic disturbances, supersonic aeroplanes, etc.) have been observed in ecosystems supporting mammalian populations that are blighted by clusters of traditional and new variant strains of transmissible spongiform encephalopathy (TSE). But TSEs will only emerge in those 'infrasound-rich' environments which are simultaneously influenced by eco-factors that induce a high manganese (Mn)/low copper (Cu)-zinc (Zn) ratio in brains of local mammalian populations...

Klaus Joachim Zülch (1910-1988) since 1959 head of a department of the german Max-Planck-Society, deeply influenced the neurological sciences in post-war Germany. The department with the name Abteilung für allgemeine Neurologie (i.e. department of general neurology) constituted a section of the renowned Max-Planck-Institut für Hirnforschung (i.e. institute for brain research) and found its place in Cologne. At the same time he was in charge of the local neurology unit of the municipal Cologne hospital, on the right Rhine riverside in Köln (Cologne) Merheim...

Carnosine is a naturally occurring dipeptide (beta-alanyl-L-histidine) found in muscles, brain and other tissues. This study was designed to test the ability of carnosine to offset metabolic disturbances induced by Schistosoma mansoni parasitism. Results indicate that parasitic infection caused elevation of liver weight/body weight in S. mansoni-infected hamsters, induced lipid peroxidation and reduced glycogen levels. Moreover, adenylate energy charge (AEC) and ATP/ADP and ATP/AMP concentration ratios were markedly lower in infected hamsters...

Membrane-impermeant quaternary amine local anesthetics QX314 and QX222 can access their binding site on the cytoplasmic side of the selectivity filter from the outside in native cardiac Na(+) channels. Mutation of domain IV S6 Ile-1760 of rat brain IIA Na(+) channel or the equivalent (Ile-1575) in the adult rat skeletal muscle isoform (mu 1) creates an artificial access path for QX. We examined the characteristics of mutation of mu 1-I1575 and the resulting QX path. In addition to allowing external QX222 access, I1575A accelerated decay of Na(+) current and shifted steady-state availability by -27 mV...

It has been proposed that NAD depletion resulting from excessive activation of poly(ADP-ribose) polymerase is responsible for secondary energy failure after transient cerebral ischemia. However, this hypothesis has never been verified by measurement of ATP and NAD levels in the same tissue sample. In this study, we therefore investigated the effect of transient focal cerebral ischemia on the temporal profiles of changes in the levels of energy metabolites and NAD. Ischemia was induced in mice by occluding the left middle cerebral artery using the intraluminal filament technique...

The essential issue of electroshock therapy (ECT) is the activity of physical stimulus, i.e., the electric current, on the disturbed structures of the brain. ECT sessions--when chronically applied for evoking antidepressive effects--are responsible for the appearance of excessive incitement in the neuronal net in the brain tissue in a form of self-sustaining after-discharge (SSAD) (convulsive attack characteristic for ECT). The study presents the computer research on basic biophysical phenomena of electroshock therapy (flow of electric current in the structures of the head just before convulsive attack)...

The cortex of the frontal lobe reaches maximum phylogenetic development in the brain of the human. It is cortex devoted to the organization of action in all neurobiological and cognitive domains - skeletal movement, eye movement, speech and logical reasoning. Thus the frontal cortex may be called 'motor cortex' in the widest sense. The association cortex of the frontal lobe, commonly called prefrontal cortex, is in charge of the temporal organization of behaviour, speech and thinking. Prefrontal lesions frequently lead to disorders of temporal organization, especially in thinking and the spoken language...

The present study characterized the in vitro NMDA receptor antagonistic properties of novel amino-alkyl-cyclohexane derivatives and compared these effects with their ability to block excitotoxicity in vitro and MES-induced convulsions in vivo. The 36 amino-alkyl-cyclohexanes tested displaced [3H]-(+)-MK-801 binding to rat cortical membranes with K(i)s between 1.5 and 143 microM. Current responses of cultured hippocampal neurones to NMDA were antagonized by the same compounds with a wide range of potencies (IC50s of 1...

By means of tele-receptor signals (vision, hearing, olfaction) the mammalian brain is almost continuously informed about environmental events, and whenever these are interpreted as positive or negative challenges the cerebral "super-controller" can, for coping with the anticipated situation, select the most appropriate among a number of pre-formed hypothalamic reaction patterns. These are organized as combined engagements of the somatomotor, visceromotor and hormonal efferent links, whereby a variety of behavioural responses can be elicited, where each is accompanied by appropriate adjustments of inner organ systems, metabolism, etc...

The data are presented concerning the state of vascular brain system during experimental neurosis in Wistar rats, the intricate cerebral hemodynamical disturbances, shifts in activity of the crucial enzymes of the mitochondrial respiratory chain, and activation of the lipid peroxidation processes. The positive results on treatment of the experimental and clinical neuroses with antioxidants which have antihypoxic properties are presented. Results on increase of resistance to stress in rats under the influence of negatively charged air ions with expressed antihypoxic are discussed...

The present study was designed to clarify whether ontogenetic differences in the vulnerability of the brain towards hypoxic-ischemic insults are only caused by the low cerebral energy demand of immature animals or whether there are additional mechanisms, such as protein synthesis (PSR), that may be involved in this phenomenon. We therefore measured tissue levels of adenylates and PSR in hippocampal slices from immature (E40) and mature (E60) guinea pigs fetuses and from adult guinea pigs during in vitro ischemia and 24 h of recovery using a recently modified method...

To elucidate the mechanisms of ischemic cell damage, biochemical disturbances developing during and following in vitro ischemia of 5, 10 or 15 min duration were compared in hippocampal slices prepared from gerbil and rat brains. During ischemia the release of glutamate from slices into the medium was determined, and after ischaemia and 10 min of recovery slices were analyzed for ATP levels, adenylate energy charge and cGMP content. The release of glutamate into the medium during in vitro ischemia and the recovery of energy metabolism determined after 10 min of recovery was almost identical in slices prepared from gerbil and rat hippocampi...

A high prevalence of sleep apnoea was found in a group of men occupationally exposed to organic solvents. Workers with long term exposure to organic solvents often report symptoms such as fatigue, forgetfulness, and concentration difficulties. These symptoms are strikingly similar to those reported by patients with obstructive sleep apnoea syndrome (OSAS). This is a frequently diagnosed disorder characterised by disturbed sleep causing psychic or somatic complications and daytime sleepiness. A study was undertaken to evaluate whether people with long term occupational exposure to organic solvents have a higher prevalence of sleep apnoea than the general population...

To initiate delayed neuropathy (DN) in adult hens organophosphates and phosphonates must inhibit most neural NTE and the inhibited NTE must undergo an 'aging' reaction. Phosphinates and those chiral isomers of phosphonates which produce non-aging NTE do not cause DN but act as prophylactic agents. Some racemic phosphoramidates cause DN although the inhibited NTE in autopsy samples can be reactivated in vitro (Johnson, Read and Vilanova, 1991, Arch. Toxicol., 65, 618-624). We now report that pure R(+)isomer of O-n-hexyl S-methyl phosphorothioamidate (5-20 mg/kg per os) caused slight acute effects but typical DN associated with high inhibition of NTE in brain, spinal cord and sciatic nerve (maximum by 6-24 h): the inhibited NTE was easily reactivated by KF (presumed not aged)...

This article introduces a Symposium devoted to Neuropathy Target Esterase (NTE). The characteristics of the disorder known as OPIDP are described and the steps by which NTE was identified as the target are summarised. Studies with many organophosphates, phosphinates and chiral phosphonates are entirely consistent with a 2-step process of initiation referred to as 'NTE (70-80%) aging': about 70-80% of available nervous system NTE is first covalently phosphylated causing inhibition of esterase activity, and then the molecules of inhibited NTE undergo a covalent bond-cleavage leaving a negative charge in the region of the still-bound phosphorus...

The cytotoxic effect of aluminium was studied on cultured goat brain microvascular endothelial cells used as an in vitro model of the blood-brain barrier. Confluent monolayers of these cells were exposed for 4 days to aluminium maltol and, for control purposes, to maltol alone, and also to cadmium chloride as a known cytotoxic substance. The localization of plasmalemma-bound enzymatic activities of 5'-nucleotidase and Ca(2+)-ATPase and the distribution of sialic acid residues were studied at the ultrastructural level...

The authors present comparative data on the extent, nature, and impact of diagnosed mental disorder among children under 18 years of age seen during 1975 in four organized health care settings. Between 3.3% and 10.1% of the children seen were diagnosed as having a mental disorder in the study year, representing an annual prevalence of between 2.2% and 8.2% of the "covered" child populations. Transient situational disturbances, behavior disorders, and special symptoms were the most common diagnoses; the more severe disorders (organic brain disease, schizophrenia, and affective and other psychoses) accounted for less than 4% of all diagnosed mental disorder...

This paper proposes a new mechanism for radiopharmaceutical uptake, which may be applicable to a variety of clinical studies. Many tissues and organs have low intracellular pH, either normally or as a result of various metabolic disturbances. We have developed a series of compounds that are neutral and lipid-soluble at blood pH. These molecules can diffuse freely into cells. In those regions where intracellular pH is low, they pick up a hydrogen ion and become charged. In this form they are no longer lipid-soluble and are trapped because they cannot diffuse out of the cell...

Hypertensive disease is known to increase the risks in connection with acute changes in blood pressure due to the presence of pronounced structural as well as functional changes in the cardiovascular system. In the present study the metabolic consequences of fixed haemorrhagic hypotension [mean arterial pressure (MAP) 70 and 45 mmHg] were studied in spontaneously hypertensive (SHR) and in normotensive rats (WKY). Blood gases and acid-base balance, blood glucose, liver (ATP, glucose, lactate) and brain (ATP, ADP, AMP, CP, glucose, lactate) metabolites were determined in unbled animals and after 35 min hypotension in bled animals...

Numerous methods used for the isolation of brain microvessels involve procedures which disturb the structural integrity of the cells and their organelles. In the present study, analysis of the adenylate energy charge and content as well as the incorporation of adenosine derivatives in isolated rat brain microvessels indicated a lesion of the mechanisms of energy production. The results show that experiments on isolated microvessels prepared by a mechanical homogenization exerting shear forces should be interpreted with caution when the rate of energy metabolism is a significant factor in the study...