The heterogeneity of the specificities of anti-acetylcholine receptor (anti-AChR) antibodies of myasthenia gravis (MG) patients has been demonstrated by comparing reactions against a panel of xenogeneic AChR. For each patient there was a more or less unique cross-reactivity profile. Such heterogeneity emphasizes the need to use human AChR for the routine detection of anti-AChR. In vitro cross-reactivity was important in predicting the effect of anti-AChR after passive transfer to rats. Specificity may influence the outcome in human neonates receiving maternal anti-AChR via the placenta. In contrast to the extreme heterogeneity seen in spontaneous MG, the antibodies associated with D-penicillamine-induced MG were more homogeneous.

Animals↗

PubMedDate not supplied

The potential for dengue in South Africa: vector competence tests with dengue 1 and 2 viruses and 6 mosquito species.

Six mosquito species, selected because their prevalence, distribution and ecology favoured them as potential vectors of dengue (DEN) in South Africa, were tested for vector competence with DEN 1 and 2 viruses. After intrathoracic inoculation with DEN 1, head squash infection rates (HSIRs) by the indirect fluorescent antibody test were 92-100% in all species except Aedes demeilloni, for which rates were < 40%. After an infective blood meal containing DEN 1 and DEN 2 virus respectively, Ae. demeilloni, Ae. simpsoni and Eretmapodites quinquevittatus were refractory to infection, while the 3 other species became infected. Five populations of Ae. aegypti each 'transmitted' both serotypes into capillary tubes. With DEN 1, HSIRs and transmission rates (TRs) varied from 11% to 54% and 67% to 100%, while with DEN 2 they ranged from 19% to 46% and 71% to 86%. The mean vector competence index (VCI) was highest for Durban (0.47 for DEN 1 and 0.34 for DEN 2), while VCIs for the remaining populations varied from 0.13 to 0.28 (DEN 1) and 0.18 to 0.23 (DEN 2). With DEN 1, HSIRs for Ae. strelitziae and Ae. furcifer were 33% and 3% respectively, but no transmission occurred. With DEN 2, results for Ae. strelitziae were HSIR = 56%, TR = 29% and VCI = 0.16, while values for Ae. furcifer were HSIR = 12%, TR = 50% and VCI = 0.06. It is concluded that populations of Ae. aegypti are potentially the best vectors for both serotypes of the virus and that the Durban population could act as the most efficient vector in an urban or peri-urban epidemic.(ABSTRACT TRUNCATED AT 250 WORDS)

Aedes↗

PubMedDate not supplied

Laboratory automation: a model.

Today's health care providers are keenly aware of the need to do "better with less" in an environment of shrinking resources. This article describes a process for automating laboratory services that is based on expertise, safety, productivity, and a set of guiding principles. The process used to create this model, which integrates people with the flow of information and materials, can be used to re-engineer any knowledge-based process.

Canada↗

PubMedDate not supplied

Polio vaccine payback is still not enough.

Explore the source record for details and available documents.

Child↗