Brain dysfunction in social drinkers

Thirty-four social drinkers who had referred themselves to the Regional Brain Damage Unit for assessment of the effects of drinking alcohol were compared with 42 volunteer control subjects of equivalent age but with low alcohol intake, using two 'learning' tests — the Rey Auditory Verbal Learning Test (RAVLT) and the Austin Button Maze. The Maze Test gave no evidence of disorder, but the two groups were significantly different on the RAVLT. No abnormalities in standard cognitive tests were apparent. These results suggest that a deficit in learning ability may be an early feature of the brain dysfunction associated with excessive alcohol consumption.     

Interventional dysrhythmia management and the role of laser

Drug-resistant dysrhythmias may require interventional management. Laser energy can be used for interruption or destruction of dysrhythmia-generating foci or conductive pathways. Lasers may, therefore, be useful tools for interventional management of supraventricular or ventricular dysrhythmias and preexcitation syndromes. Although the role of lasers in interventional dysrhythmia management is not clearly defined, the advantages may be substantial.     

Petit Mal-Grand Mal ECT: A Method to Induce Seizures Without Barbiturate Anesthesia

Petit mal-grand mal (PM-GM) electroconvulsive therapy (ECT) is a technique developed by Impastato to elicit unconsciousness with a subconvulsive electrical stimulus, rather than with barbiturate anesthesia. Muscle relaxation is produced with succinylcholine chloride before stimulus is applied. The cases reported here illustrate applications of the technique to depressed patients with severe cardiac and pulmonary disease, and the use of PM-GM ECT in a patient in whom seizures could not be elicited by the usual ECT technique is described.     

A model of spatial localization and its application to strabismus

Visually guided, spatially oriented behavior involves an ongoing integration of signals regarding the loci of the retinal images and the position and orientation of the eye. In the strabismic this requires an altered spatial metric resulting from a functional readaptation to avoid confusion and diplopia. A comparator mechanism for evaluating these two signals is presented. A case report using "disruptive" therapeutic procedures that deliberately alter the strabismic's visual-postural control system is presented. A treatment plan for altering the anomalous binocular link, a characteristic of the well adapted strabismic, is described and related to the comparator mechanism.     

Cathepsin-D expression in cervical carcinoma and its prognostic significance

An immunohistochemical study was made of cathepsin-D protein expression in each of the three main types of uterine cervical carcinoma (squamous carcinoma, adenosquamous carcinoma and adenocarcinoma) with particular reference to lymph node status and prognosis. Of the 61 cases, 54.1% showed cytoplasmic staining in more than 2.5% of tumour cells counted. Cathepsin-D expression was significantly higher in adenocarcinoma (mean -3.128) than in squamous carcinoma and adenosquamous carcinoma (mean –3.709,P=0.047 using logit transformation). Cathepsin-D had no prognostic value in any of the three tumour types. No relationship was found between cathepsin-D staining and lymph node status and there was no advantage in adding cathepsin-D values to lymph node status. These results suggest that immunostaining for cathepsin-D protein expression is unlikely to be of use as a prognostic marker.     

Voltage-dependent, pertussis toxin insensitive inhibition of calcium currents by histamine in bovine adrenal chromaffin cells

Histamine is a known secretagogue in adrenal chromaffin cells. Activation of G-protein linked H(1) receptors stimulates phospholipase C, which generates inositol trisphosphate leading to release of intracellular calcium stores and stimulation of calcium influx through store operated and other channels. This calcium leads to the release of catecholamines. In chromaffin cells, the main physiological trigger for catecholamine release is calcium influx through voltage-gated calcium channels (I(Ca)). Therefore, these channels are important targets for the regulation of secretion. In particular N- and P/Q-type I(Ca) are subject to inhibition by transmitter/hormone receptor activation of heterotrimeric G-proteins. However, the direct effect of histamine on I(Ca) in chromaffin cells is unknown. This paper reports that histamine inhibited I(Ca) in cultured bovine adrenal chromaffin cells and this response was blocked by the H(1) antagonist mepyramine. With high levels of calcium buffering in the patch pipette solution (10 mM EGTA), histamine slowed the activation kinetics and inhibited the amplitude of I(Ca). A conditioning prepulse to +100 mV reversed the kinetic slowing and partially relieved the inhibition. These features are characteristic of a membrane delimited, voltage-dependent pathway which is thought to involve direct binding of G-protein betagamma subunits to the Ca channels. However, unlike virtually every other example of this type of inhibition, the response to histamine was not blocked by pretreating the cells with pertussis toxin (PTX). The voltage-dependent, PTX insensitive inhibition produced by histamine was modest compared with the PTX sensitive inhibition produced by ATP (28% vs. 53%). When histamine and ATP were applied concomitantly there was no additivity of the inhibition beyond that produced by ATP alone (even though the agonists appear to activate distinct G-proteins) suggesting that the inhibition produced by ATP is maximal. When experiments were carried out under conditions of low levels of calcium buffering in the patch pipette solution (0.1 mM EGTA), histamine inhibited I(Ca) in some cells using an entirely voltage insensitive pathway. We demonstrate that activation of PTX insensitive G-proteins (most likely Gq) by H(1) receptors inhibits I(Ca). This may represent a mechanism by which histamine exerts inhibitory (in addition to previously identified stimulatory) effects on catecholamine release.