Acute renal failure and dermal necrosis due to bee stings: report of a case in a child

Although several cases of reactions to bee venom including acute renal failure have been reported, the literature from Africa is scanty and that concerning children virtually non-existent. We report a child who was stung by over 1,000 bees and developed acute renal failure and extensive scalp necrosis. The pathogenesis of these complications is discussed and the importance of their public awareness stressed.     

In vivo seasonal assessment of Plasmodium falciparum sensitivity to chloroquine in two different malaria endemic communities in Southern Ghana

A two year (1992 to 1993) in vivo assessment of Plasmodium falciparum sensitivity to chloroquine was conducted in two communities at Dodowa (hyperendemic) and Prampram (mesoendemic) in Southern Ghana. A slightly modified World Helath Organization standard field test (7 day test) for response of Plasmodium falciparum asexual parasites to chloroquine was used for the survey. In 1992, 16.2% (12/74) responses were classified as exhibiting chloroquine resistance at RI (14.8% ) and RII (1.4%) in the dry season and 8.2% (10/122) responses at RI in the wet season in the hyperendemic community. Only a single response (1/144; 0.7%) at RI showed resistance in the mesoendemic community. The rest of the responses in both communities were classified as sensitive to chloroquine. In the hyperendemic community, 8.4% (13/154) of responses in the dry season showed resistance at RI and 1.3% (82/150) at RI (0.7%) and RII (0.7%) in the wet season in 1993. In the mesoendemic community 1 (1.0%) response was resistant at RI in the wet season. The rest of the responses were classified as sensitive responses to chloroquine. No RIII response was encountered in any of the communities. The pattern of RI and RII responses did not show any seasonal variations in the mesoendemic community. However, they were generally higher in the dry season than in the wet season in the hyperendemic community.     

Study of the HLA system in Burkitt's lymphoma

Seventy-eight patients with Burkitt's lymphoma and seventy controls from Ghana were typed for HLA-A, B, C and DR antigens, to determine whether there is an association between the HLA system and Burkitt's lymphoma. Increased relative risk was observed in Burkitt's lymphoma patients with DR7, HLA-A1 and B12 (BW44).     

The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry

Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus is determined by a combination of environmental and genetic factors, which include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2 cannot explain the clustering of type 1 diabetes in families, and a role for other genes is inferred. In the present report we describe linkage and association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong candidate gene for T cell- mediated autoimmune disease because it encodes a T cell receptor that mediates T cell apoptosis and is a vital negative regulator of T cell activation. In addition, we provide supporting evidence that CTLA-4 is associated with susceptibility to Graves' disease, another organ- specific autoimmune disease.      

High frequency of circulating gamma delta T cells with dominance of the v(delta)1 subset in a healthy population

TCR gamma delta(+) cells constitute <5% of all circulating T cells in healthy, adult Caucasians, and V(delta)1(+) cells constitute a minority of these cells. In contrast to TCR alpha beta(+) cells, their repertoire is selected extrathymically by environmental antigens. Although increased frequencies of V(delta)1(+) cells are found in several diseases, their function remains obscure. Here we show that the frequency of peripheral blood gamma delta T cells in healthy West Africans is about twice that of Caucasians, mainly due to a 5-fold increase in V(delta)1(+) cells, which is consequently the dominant subset. No age dependency of V(delta)1 frequencies was identified and the V(delta)1(+) cells in the African donors did not show preferential V(gamma) chain usage. Analysis of the CDR3 region size did not reveal any particular skewing of the V(delta)1 repertoire, although oligoclonality was more pronounced in adults compared to children. The proportions of CD8(+), CD38(+) and CD45RA(hi)CD45RO(-) cells within the V(delta)1(+) subset were higher in the African than in the European donors, without obvious differences in expression of activation markers. No significant correlations between levels of V(delta)1(+) cells and environmental antigens or immunological parameters were identified. Taken together, the evidence argues against a CDR3-restricted, antigen-driven expansion of V(delta)1(+) cells in the African study population. Our study shows that high frequencies of TCR gamma delta(+) cells with dominance of the V(delta)1(+) subset can occur at the population level in healthy people, raising questions about the physiological role of V(delta)1(+) T cells in the function and regulation of the immune system.     

HLA-DR7 association with African Burkitt's lymphoma

Association between HLA-DR7 and Burkitt's lymphoma previously reported has been confirmed by a second study. Analysis of additional data from a second study of 33 Ghanaian patients with African Burkitt's lymphoma and 54 Ghanaian controls matched for age and ethnic origin showed that 39.4% of cases, but only 14.8% of controls, had HLA-DR7 (p less than 0.01). The relative risk of 3.7 is similar to that observed in the earlier study (3.3). Combining the earlier and present studies, analysis of clinical data from 94 patients with Burkitt's lymphoma and 116 controls shows the relative risk of Burkitt's lymphoma among individuals with HLA-DR7 was 3.4 (p less than 0.001). There was an increased relative risk of the disease associated with HLA-DR7 in: patients under 10 years of age; and patients with advanced stages of disease (Stage III or IV). However, comparison of relative risks by sequential analysis of 2 X 2 tables showed that these differences by age and stage were not statistically significant.     

The challenges of ambiguous genitalia.

In this paper, we assessed 71 patients between January 1985 and December 1990. Patients with ambiguous genitalia who were seen in the out-patient clinics of both the Paediatric and Urology Departments in the Harare Group of Hospitals. The majority of patients were seen by both the paediatricians and the urologists as children with anomalous genitalia, and a good number were referred to the Urological out-patients as cases of severe perineal, penoscrotal hypospadias, or cryptorchidism. Generally, there were three categories of patients who were seen. The first group were patients referred with severe hypospadias, perineal or penoscrotal and who only, after chromosomal studies, were then categorised into the ambiguous genitalia group. These patients were sent for chromosomal studies because of the concomitant cryptorchidism or, as they were suspected of having ambiguous genitalia because of the well developed labial folds without palpable testes. The second group of patients were patients seen at birth with incongruities which typify ambiguous genitalia. The third group was those who attended the urology clinics with a wish of having surgery performed to render their "phallic organ" long or good enough to help achieve rigidity for sexual intercourse. In the 71 patients seen, the classification had been made and surgery performed on a great majority of them at an early stage, to avoid later catastrophes and the possibility of the development of gonadoblastoma.     

葛根素的心血管系统药理作用及机理研究

纵观近年来对葛根素在心血管系统药理作用及机理研究方面的进展发现，葛根素对心血管系统具有抗心律失常、降血压、扩张冠状动脉、抗心肌缺血、抗过氧化、抗缺血-再灌注损伤、影响血液动力学和血小板聚集、保护血管等作用。其临床应用前景良好，其药效机制研究及临床应用有待更深一步的探究。