Detection and localization of single-base sequence differences in foot-and-mouth disease virus genomes by the RNase mismatch cleavage method.

The RNase mismatch cleavage method was examined for its efficiency of indicating single-base sequence differences in the capsid protein-coding regions of different foot-and-mouth disease virus subtype O1 strains. The method was found suitable for indicating such differences. RNase A as well as RNase T1 contributed to substrate conversion. Examples for the cleavage of eleven different single-base mismatches in RNA double-strands are now known. All virus genomes found to differ from each other exhibited three or more non-neighboured single-base sequence differences. Other genomes found to be indistinguishable by this method were those of a recent field isolate adapted to cell culture, and those of a vaccine production strain; its progeny was transmitted to pig and cow and then analyzed. The results suggest that host change does not necessarily select for antigenic variant virus, and that virus submitted to some kind of selection pressure is changed at more than one position.     

Hyperexcitability associated with localizable lesions in epileptic patients

Intracellular recordings from neurons were carried out in cortical slices obtained from tissue removed from patients suffering from intractable seizures. The patients were divided into two groups based on the presence or absence of an anatomical abnormality that could be imaged preoperatively. The lesion or its surround was the presumptive epileptogenic area. The tissue removed from the patients without lesions was removed either for biopsy purposes or for access to epileptic tissue and was not considered epileptogenic. All neurons from patients without an imageable lesion, and some (19%) from patients with an imageable lesion, responded to orthodromic stimuli with a sequence of synaptic excitation followed by inhibition; these properties resembled those of normal rodent cortical slices. Different responses, classified as abnormal, were observed in 81% of the neurons in tissue specimens obtained near lesions. The most common was prolonged synaptic excitation with no noticeable inhibition, even at high stimulus strengths. In three resections, long latency all-or-none depolarization shifts were observed that resemble the classic paradoxical depolarization shift seen in in vivo extracellular recordings. Loss of specific inhibitory systems within the cortex may contribute in part to these abnormal responses.     

The incidence of gout in patients with Dupuytren's disease.

In a retrospective study we found that the incidence of gout in patients with Dupuytren's disease is 3.5%. The mean serum uric acid was 330 mumol/l. (5.5 mg./100 ml.) in men and 240 mumol./l. (4.0 mg./100 ml.) in women. The rate of hyperuricaemia was 7%. These are not significantly higher than the expected figures in Britain.     

Using educational interventions to improve the handwashing habits of preschool children

The effectiveness of educational activities on changing the handwashing habits of preschool children was evaluated using parental surveys and direct observations. Baseline handwashing behaviors were observed and recorded, and parents completed a pre-intervention survey. After interventions were administered, post-intervention data was collected on preschoolers' handwashing habits. Children participated in one, three or five handwashing intervention activities. Results of this study indicate that the educational activities implemented resulted in increased knowledge of the importance of proper handwashing and in positive changes in the children's handwashing habits, particularly for the children who participated in all five interventions.     

Phase mapping from left ventricular radionuclide ventriculograms: interobserver reliability and accuracy of the programme

Phase analysis of data from radionuclide ventriculograms is known to provide space-time information on the mechanical emptying of pixels located in the ventricular regions. It could therefore perhaps be useful for detecting abnormal sequences of contraction of the ventricles as well as to localize sites of premature electromechanical action. The phase programme used in this investigation is designed to trace the electromechanical action of the ventricles from colour-coded phase images (first harmonic Fourier transform), not only visually from a cinematic representation, but particularly from a data output of x, y coordinates and phase angles of sites chosen as they empty in the ventricular regions. Six healthy baboons were subjected to conventional radionuclide ventriculography, performed hourly for the duration of 11 h under anaesthesia. The programme was used by two independent observers to map the progression of emptying for each of the thus acquired 66 left ventricular phase images. The interobserver reliability and the accuracy achieved in mapping normal contraction patterns was found to be good. Abnormalities which appeared during the prolonged anaesthesia and which were confirmed with 12 lead electrocardiography were likewise detected consistently.     

CongenitaI Polycystic Disease of the Brain: Report of an Unusual Case

Multiple congenital supratentorial intracerebral cysts occurred in a newborn infant. The cysts, of varying size, content and lining, occupied the cerebral hemispheres. They formed a mosaic pattern on CT scan and left no trace of a recognisable ventricular system. Multiple surgical procedures were performed during the first year of life, and at one year the child was very well and asymptomatic, with two functioning shunts.     

In vivo actions of insulin-like growth factor-I (IGF-I) on bone formation and resorption in rats

The in vivo action of insulin-like growth factor-I on bone metabolism has been studied using a new model. Insulin-like growth factor-I (IGF-I) was continuously infused into the arterial supply of the right hindlimb of ambulatory rats for up to 14 days and the effects on cortical and trabecular bone formation and the number of osteoclasts were determined by histomorphometric techniques. The contralateral limb acted as an internal control. IGF-I infusion significantly increased cortical bone formation (p less than 0.01). Trabecular bone was increased 22% (p = 0.07), but the infusion was only for seven days. These effects of IGF-I were age dependent, being absent in young, rapidly growing animals, but present at least until one year of age. IGF-I appears to be a purely anabolic hormone for bone formation, since it significantly stimulates osteoblasts and decreases the number of osteoclasts. Thus, although IGF-I mediates the growth-promoting effect of growth hormone, it does not mediate growth hormone's action on bone resorption.