Structural polymorphism of glycophorins demonstrated by immunoblotting techniques

We have explored the polymorphism of the glycophorin system in the human erythrocyte membrane using the immunoblotting techniques and examining 52 individuals selected without prior bias as to their serologic state and ten documented serologic variants of M, N, S, s blood group system. Polyclonal antisera to alpha glycophorin and to alpha glycophorin CNBr carboxyl terminal fragment C (residues 82-131) and M and N specific monoclonal antibodies (MoAbs) were used. The first two reagents detect specific regions of the alpha glycophorin molecule and all electrophoretically resolved species of glycophorins immunologically related to alpha and delta glycophorins (delta glycophorin, [alpha-delta] hybrids and other glycophorins with an alteration in the carboxyl terminal segment); the M and N MoAbs identified the glycophorin species containing or lacking the M or N determinant in the amino terminal octapeptide structures. We find that immunoblotting confirmed in all cases the serologically determined phenotype; we also find that polymorphic forms of the glycophorin system are relatively infrequent; immunoblotting, independent from serologic testing, was capable of detecting five mutants, two most likely S-s-U-phenotypes; a new glycophorin species was detected in normal red cells with both antiglycophorin and antipeptide C sera, which is not evident with MoAbs; immunoblots of known glycophorin variants (En(a-), U-, Mg, Mi I, II, III, V, and Sta) confirmed but also extended our knowledge of the abnormal glycophorins involved; and the He+ and Wrb(-) cells showed normal patterns.     

Antibiotic susceptibility of microorganisms at a general hospital in Lagos,Nigeria

OBJECTIVE: To determine susceptibility patterns of microorganisms to antibiotics in a large general hospital in Lagos, Nigeria. METHODS: Clinical samples received in the laboratory were processed according to standard methods. Susceptibility to antibiotics was done using a disk diffusion technique. RESULTS: Five hundred and fifty-one samples from urine, wound, reproductive tract and other body fluids were analysed. The most frequently isolated pathogens (n=586) were Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Most of the organisms were sensitive to ciprofloxacin, perfloxacin, cefuroxime, ceftriaxone and azithromycin but were resistant to ampicillin, cotrimoxazole and penicillin. Pseudomonas aeruginosa was multi-resistant. The susceptibility pattern obtained at this hospital is similar to what obtains in teaching hospitals in Nigeria. CONCLUSION: Microorganisms isolated at this hospital are more sensitive to newer antibiotics.     

Pattern of soft tissue injuries to the oro-facial region in Nigerian children attending a teaching hospital

Summary. Objective. This study was designed to determine the aetiological factors and pattern of oro‐facial soft tissue injuries among children in a suburban Nigerian population. The problems encountered in the management of the patients are also highlighted. Setting. Obafemi Awolowo University Teaching Hospitals’ Complex, Ile‐Ife, Osun State Nigeria. Sample and methods. This prospective study was carried out in children aged ≤ 15 years who presented with oro‐facial soft tissue injuries between July 1996 and December 1997. Data was collected from a clinical examination of the child and a questionnaire completed by the parent or carer. Results. During the study period, 174 children were managed for oro‐facial soft tissue injuries, an incidence of 1·1%, out of a total of 15 582 child admissions. A male preponderance was found (1 : 0·74). The mean age ± SD was 7·3 ± 4·2 years and the range was 9 months–15 years. Falls were the most common aetiology followed by road traffic accident. The forehead was the most frequently injured site. A mortality of 3·4% was found. Although animal bites and burns accounted for only 13·8% of all injuries, all the deaths were a result of these aetiologies. Road traffic accidents and burn victims had the longest hospital stay. Conclusion. Although falls and road traffic accidents are frequent causes of oro‐facial soft tissue injuries, less common causes, like burns and dog bites are more likely to result in death.     

An anti-EnaTS detected in the serum of an MiI homozygote

The serum of EH reacted with all red cells (RBCs) except her own, ficin- or trypsin-treated red cells, and En(a-) red cells. This reactivity defined an anti-EnaTS specificity. The red cells of the proposita typed as M-N+S-S+, Vw+Mur-Hil-Hut-Anek-Lane-, Wr(a-b+), EnaKT+. Red cells of five relatives were Vw+ and positive with her serum. Titration studies suggest that EH is genetically an MiI homozygote and that her Vw+ relatives are MiI heterozygotes. There is no history of consanguinity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting studies have agreed with the serologic observations. A variant sialoglycoprotein of faster mobility than normal glycoprotein A, but no normal glycoprotein A, was detected on her red cells. Treatment with N-glycanase did not alter the mobility, which indicated that there was no N-glycosylation of residue 26. These findings are in agreement with the reported properties of the Mi.I-specific glycoprotein A. The relatives' Vw+ red cells showed the variant sialoglycoprotein and normal glycoprotein A. EH appears to be the first reported MiI homozygote.     

Antibiotic resistance in bacteria - an emerging public health problem

The discovery and eventual introduction of anti-microbial agents to clinical medicine was one of the greatest medical triumphs of the twentieth century that revolutionized the treatment of bacterial diseases. However, the gradual emergence of populations of antibiotic-resistant bacteria resulting from use, misuse and outright abuse of antibiotics has today become a major public health problem of global proportions. This review paper examines the origins and molecular epidemiology of resistance genes, global picture of antibacterial resistance, factors that favour its spread, strategies for its control, problems of control and the consequences of failure to contain antibiotic resistance in bacteria.