Disruption of the acyl-CoA:cholesterol acyltransferase gene in mice: evidence suggesting multiple cholesterol esterification enzymes in mammals

The microsomal enzyme acyl-CoA:cholesterol acyltransferase (ACAT; EC 2.3.1.26) catalyzes the esterification of cellular cholesterol with fatty acids to form cholesterol esters. ACAT activity is found in many tissues, including macrophages, the adrenal glands, and the liver. In macrophages, ACAT is thought to participate in foam cell formation and thereby to contribute to atherosclerotic lesion development. Disruption of the gene for ACAT (Acact) in mice resulted in decreased cholesterol esterification in ACAT-deficient fibroblasts and adrenal membranes, and markedly reduced cholesterol ester levels in adrenal glands and peritoneal macrophages; the latter finding will be useful in testing the role of ACAT and macrophage foam cell formation in atherosclerosis. In contrast, the livers of ACAT-deficient mice contained substantial amounts of cholesterol esters and exhibited no reduction in cholesterol esterification activity. These tissue-specific reductions in cholesterol esterification provide evidence that in mammals this process involves more than one form of esterification enzyme.     

Emergency food control assistance for the prevention and control of cholera in Latin America

The cholera epidemic, which first struck Peru in early 1991, spread to several countries in the region causing serious public health problems and affecting the food production sector, food consumption and exports. This paper summarizes the technical assistance provided by FAO to attempt to stem the spread of the epidemic.     

Validation of the motorcycle operator skill test

This study's aim was to determine what demographic and experiential factors are related to scores on the Motorcycle Operator Skill Test. It was expected that the greater the riding experience and training, the higher would be the skill scores. Applicants for a motorcycle operator's licence were administered a questionnaire and the Skill Test prior to taking the licensing test. The questionnaire and skill data for those applicants passing the licensing test were analyzed and it was found that skill was greater among the more experienced riders (i.e. miles ridden motorcycle) but unexpectedly it was lower among training course graduates. Also, males performed better than females and younger motorcyclists performed better than older motorcyclists. Further analyses revealed that course graduates had less skill than untrained riders even when experience differences were controlled. The implications of the present data for the effectiveness of motorcycle training courses are discussed.     

Epidemiological and clinical patterns of genital lesions

A 5-year study of 668 patients with genital lesions revealed that teenagers and those in the age group of 20 to 40 are most vunerable. The poor, the uneducated and unmarried persons are at high risk. Chancroid and syphilis are the majority of cases. Inguinal bubo, herpes pregenitalis, condylomata acuminata, erosive balanitis and traumatic ulcers were seen less frequently. Most of the genital lesions had the classic clinical features. The findings of this study suggest that the pattern of genital lesions is showing borderline changes.     

How to improve computer advisory services

There are an increasing number of active computer users who are not computer professionals and so require continuous guidance in order to effectively employ computer facilities. In universities such guidance is provided by a formal advisory service. While advisory services play a vital role for university users, there are numerous problems which can detract from their effectiveness. This paper identifies many of these problems, and recommends ways of overcoming them. These suggestions are largely based on the results of a research project carried out for the past four years at the University of Liverpool. Topics considered are: (i) the assessment of various methods for organizing advisory services; (ii) the specific needs of inexpert users and strategies for effectively advising them; (iii) problems of the comprehension of computing information; (iv) guidelines for good advisory communication; (v) methods for improving the professional status of the advisory function.