Selected risk factors for coronary heart disease in male scholars from the major South African population groups

A num.ber of risk factors for coronary heart disease (CHD) in 7 groups of South African male scholars aged between 15 and 20 years were surveyed. Selection of the groups was based on socioeconomic status and comprised urban and rural blacks, Indians of higher and lower socio-economic status, coloureds of higher and lower socio-economic status, and middle-class whites. Both Indian groups, both coloured groups and the whites had a much greater prevalence and severity of CHD risk factors than the two black groups. This held for total cholesterol, low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), the HDLC/LDLC ratio, apolipoprotein B, apolipoprotein A-I, insulin, fibrinogen and mass. One exception was lipoprotein a, levels of which were higher in both black groups. In general the CHD risk factor profile was worse in the higher socio-economic groups, and it also tended to be worse in urban than in rural blacks. These findings stress the need to reduce CHD risk factors in our developed populations and to prevent their emergence in our developing peoples

Protection against heartwater by DNA immunisation with four Ehrlichia ruminantium open reading frames

We have reported previously that a recombinant DNA vaccine consisting of four Ehrlichia ruminantium (Welgevonden) open reading frames (ORFs) known as the 1H12 cocktail provided protection against a virulent E. ruminantium (Welgevonden) needle challenge in sheep. In this study, we have investigated the vaccine effectiveness of two other cocktails of E. ruminantium (Welgevonden) ORFs, as well as single ORFs from the 1H12 cocktail, to protect sheep against a virulent needle challenge with the homologous strain. Each individual 1H12 ORF provided protection, but all the animals vaccinated with the other cocktails succumbed to the challenge.The authors thank Stephen Johnston (University of Texas Southwestern Medical Center) for supplying the pCMViUBs vector and Dr. Erich Zweygarth and Antoinette Josemans (ARC-Onderstepoort Veterinary Institute, SA) for providing E. ruminantium tissue culture material for DNA extraction. This work was supported by the South African Department of Science and Technology LEAD biotechnology grant and the EU INCO-ICA4-CT-2000-30026 grant

Some aspects of glucose metabolism in normal and alloxan-diabetic rats

The in vivo incorporation of 14C from orally-administered, uniformly-labelled glucose into expired CO2, glycogen, and fatty acids has been studied with normal rats, alloxan-diabetic rats and diabetic rats treated with insulin. There was markedly less label in all three products in the diabetic rat. Treatment of the diabetic rat with an amount of insulin just sufficient to normalize the blood-sugar level restored to normal the utilization of glucose for production of CO2 and synthesis of glycogen, but elevated the synthesis of fatty acids from glucose to considerably above normal. In all three groups of rats a large part of the ingested 14C was not recovered, after the compounds studied had been taken into account

Veterinary extension on sampling techniques related to heartwater research

Heartwater, a tick-borne disease caused by Ehrlichia ruminantium, is considered to be a significant cause of mortality amongst domestic and wild ruminants in South Africa. The main vector is Amblyomma hebraeum and although previous epidemiological studies have outlined endemic areas based on mortalities, these have been limited by diagnostic methods which relied mainly on positive brain smears. The indirect fluorescent antibody test (IFA) has a low specificity for heartwater organisms as it cross-reacts with some other species. Since the advent of biotechnology and genomics, molecular epidemiology has evolved using the methodology of traditional epidemiology coupled with the new molecular techniques. A new quantitative real-time polymerase chain reaction (qPCR) test has been developed for rapid and accurate diagnosis of heartwater in the live animal. This method can also be used to survey populations of A. hebraeum ticks for heartwater. Sampling whole blood and ticks for this qPCR differs from routine serum sampling, which is used for many serological tests. Veterinary field staff, particularly animal health technicians, are involved in surveillance and monitoring of controlled and other diseases of animals in South Africa. However, it was found that the sampling of whole blood was not done correctly, probably because it is a new sampling technique specific for new technology, where the heartwater organism is much more labile than the serum antibodies required for other tests. This qPCR technique is highly sensitive and can diagnose heartwater in the living animal within 2 hours, in time to treat it. Poor sampling techniques that decrease the sensitivity of the test will, however, result in a false negative diagnosis. This paper describes the development of a skills training programme for para-veterinary field staff, to facilitate research into the molecular epidemiology of heartwater in ruminants and eliminate any sampling bias due to collection errors. Humane handling techniques were also included in the training, in line with the current focus on improved livestock welfare

Veterinary extension on sampling techniques related to heartwater research

Heartwater, a tick-borne disease caused by Ehrlichia ruminantium, is considered to be a significant cause of mortality amongst domestic and wild ruminants in South Africa. The main vector is Amblyomma hebraeum and although previous epidemiological studies have outlined endemic areas based on mortalities, these have been limited by diagnostic methods which relied mainly on positive brain smears. The indirect fluorescent antibody test (IFA) has a low specificity for heartwater organisms as it cross-reacts with some other species. Since the advent of biotechnology and genomics, molecular epidemiology has evolved using the methodology of traditional epidemiology coupled with the new molecular techniques. A new quantitative real-time polymerase chain reaction (qPCR) test has been developed for rapid and accurate diagnosis of heartwater in the live animal. This method can also be used to survey populations of A. hebraeum ticks for heartwater. Sampling whole blood and ticks for this qPCR differs from routine serumsampling, which is used for many serological tests. Veterinary field staff, particularly animal health technicians, are involved in surveillance and monitoring of controlled and other diseases of animals in South Africa. However, it was found that the sampling of whole blood was not done correctly, probably because it is a new sampling technique specific for new technology, where the heartwater organism is much more labile than the serumantibodies required for other tests. This qPCR technique is highly sensitive and can diagnose heartwater in the living animal within 2 hours, in time to treat it. Poor sampling techniques that decrease the sensitivity of the test will, however, result in a false negative diagnosis. This paper describes the development of a skills training programme for para-veterinary field staff, to facilitate research into the molecular epidemiology of heartwater in ruminants and eliminate any sampling bias due to collection errors. Humane handling techniques were also included in the training, in line with the current focus on improved livestock welfare