Rapid development and spontaneous regression of pancreatic pseudocysts documented by ultrasound

Three cases of pancreatic pseudocyst were followed serially by ultrasound examination. The entity was found to be more dynamic than has been generally thought. The rapid development and spontaneous regression of pancreatic pseudocysts was documented. The timing of surgical intervention in these cases must be reevaluated.     

Handling in infancy, taste aversion, and brain laterality in rats

Rats were handled for the first 20 days of life or were not disturbed. When adults, they were trained to approach and drink from a bottle containing sweetened milk and were then given an injection of lithium chloride to induce a taste aversion conditioned emotional response. Others were injected with physiological saline. Rats within each of the treatment groups were then randomly assigned to 4 surgical procedures: removal of the right or left neocortex; sham surgery; or no surgery. Postoperatively, they were tested for retention of taste aversion by presenting the sweetened milk and recording the amount consumed. The initial consummatory behavior was very low (showing retention of the aversion) and increased over time. There were no differences in the reacquisition curves of the non-handled groups which had received lithium chloride. The curves of the handled groups did differ: thos with an intact right hemisphere (left neocortical lesion) had the lowest asymptote, followed by the group with an intact left brain, while those with intact whole brains consumed the greatest amount of milk. In the groups given an injection of physiological saline, those with a left hemisphere lesion consumed less milk than the other groups, regardless of their early handling experience. The data show: (1) that the rat's brain is lateralized, with the right hemisphere being preferentially involved in conditioned emotional behavior; and (2) that handling in infancy makes the left hemisphere less suceptible to conditioned fear.     

Dental disease, fibrinogen and white cell count; links with myocardial infarction?

Plasma fibrinogen and white blood cell count were compared in fifty patients aged 25-50 years with periodontal disease and in fifty age-matched controls with relatively healthy periodontal tissues. Patients had significantly higher levels of fibrinogen and white cell count, and dental indices correlated significantly with these two cardiovascular risk factors on multivariate analyses. We suggest that inflammatory dental disease may be a determinant of fibrinogen level and white cell count in the general population, and that fibrinogen and white cell count may be two mediators of the link between dental disease and myocardial infarction.     

Incomplete urethral obstruction associated with dilatation of the urethra, cystitis, and pyelonephritis in a Vietnamese pot-bellied pig

A sporadic case of trilateral retinoblastoma in a male child of 20 months is described using clinical and imaging approaches. Attempts were made to find out a tumour marker by analysing human chorionic gonadotrophin (hCG), alpha-feto protein (AFP), carcinoembryonic antigen (CEA), and lactic dehydrogenase (LDH) in blood and cerebrospinal fluid (CSF). Only LDH was elevated in CSF and the rest were normal. Retinoblastoma gene could not be isolated in this patient. It is proposed that LDH in CSF should be analysed in patients with bilateral retinoblastoma who had normal brain scan initially. If LDH level in CSF is elevated, the patient should be periodically monitored by non-invasive imaging of the brain to detect intracranial tumour at an early stage.     

Computers in medicine

A growing group of institutions and individuals use Internet connections to reach information sources. Large health care organizations now see electronic records as essential to providing cost-effective health care. The Visible Human Project represents the entire three-dimensional anatomy of a cadaver.     

The effects of propofol and enflurane on single calcium channel currents of guinea-pig isolated ventricular myocytes

1. The effects of the anaesthetics, propofol (100 microM) and enflurane (3%, 1.46 mM), on single L type calcium channel currents were investigated in single myocytes isolated from guinea-pig ventricles. Channel activity was recorded from membrane patches by use of the 'cell-attached' patch-clamp technique (pipette solution containing 110 mM BaCl2, 5 microM Bay K 8644, 5 microM HEPES, pH 7.4; temperature 36 degrees C). 2. Channel conductance was calculated from the slope of the relationship between single channel current and membrane potential during step depolarizations to activate the channel over a range of approximately -20 to +20 mV. Neither propofol (6 cells) nor enflurane (7 cells) caused any significant reduction in channel conductance. 3. Both propofol (7 cells) and enflurane (9 cells) decreased the probability of the channel being open during depolarizations to +10 mV (measured from histograms of the fraction of time spent by the channel at different current levels, taking areas under the Gaussian curves fitted to the open and closed components of the distributions to represent the proportion of time spent in the two states). 4. A fraction of the current traces showed no detectable channel openings in response to step depolarizations to +10 mV. Both propofol and enflurane significantly increased the fraction of silent traces. 5. Transitions across a threshold halfway between the open and closed levels were used to define periods spent in the open and closed states. Both propofol (7 cells) and enflurane (9 cells) reduced the mean open times and increased the mean closed times of the calcium channel. 6. Histograms were plotted showing the distributions of times spent by the channels in the open and closed states. Two exponentials were fitted to the open and closed time distributions. Both propofol (7 cells) and enflurane (9 cells) shortened both time constants fitted to the open times and lengthened both time constants fitted to the closed times.7. It is concluded that both propofol and enflurane appear to alter the kinetics of opening and closing of calcium channels to favour shut channels without altering channel conductance. This effect would be expected to result in a reduction of the macroscopic calcium current and thus contribute to the negative inotropic action of these anaesthetics.