Participation in medical research as a resource‐seeking strategy in socio‐economically vulnerable communities: call for research and action

The freedom to consent to participate in medical research is a complex subject, particularly in socio‐economically vulnerable communities, where numerous factors may limit the efficacy of the informed consent process. Informal consultation among members of the Switching the Poles Clinical Research Network coming from various sub‐Saharan African countries, that is Burkina Faso, The Gambia, Rwanda, Ethiopia, the Democratic Republic of Congo (DRC) and Benin, seems to support the hypothesis that in socio‐economical vulnerable communities with inadequate access to health care, the decision to participate in research is often taken irrespectively of the contents of the informed consent interview, and it is largely driven by the opportunity to access free or better quality care and other indirect benefits. Populations' vulnerability due to poverty and/or social exclusion should obviously not lead to exclusion from medical research, which is most often crucially needed to address their health problems. Nonetheless, to reduce the possibility of exploitation, there is the need to further investigate the complex links between socio‐economical vulnerability, access to health care and individual freedom to decide on participation in medical research. This needs bringing together clinical researchers, social scientists and bioethicists in transdisciplinary collaborative research efforts that require the collective input from researchers, research sponsors and funders.     

Malaria and HIV co-infection in Hadya Zone, southern Ethiopia

BACKGROUND: Malaria and human immunodeficiency virus (HIV) are the major priority medical challenges currently facing sub-Saharan Africa, and yet little has been known on the clinical and public health implications of their co-infections. OBJECTIVES: To determine the prevalence of malaria and HIV co-infections and to describe the clinical manifestations of malaria in HIV-positive and negative malaria patients. METHODS: A cross-sectional study was conducted from October 2003 through January 2004 in three health facilities located in Hadya Zone, Southern Ethiopia. A total of 337 microscopically confirmed Plasmodium falciparum malaria patients in the age group of 15-34 years were included in the study. Anonymous HIV testing was done on the blood samples of the patients using a single enzyme linked immunosorbent assay (ELISA) technique. RESULTS: The HIV serostatus assessment revealed that 14 (4.2%) of the P. falciparum patients were seropositive for a single ELISA HIV test. No socio-demographic difference was observed between HIV positive and HIV negative malaria patients. The proportion of HIV-positives (71.4%) among patients who reported two or more malaria attacks during the last year was higher than those who only reported the current attack (28.6%). However, all patients with signs of cerebral malaria and prostration were negative for HIV test. The frequently reported symptoms of severe malaria included cerebral manifestation (76.7%), persistent vomniting (35.3%), dark urine (21.6%), inability to eat or drink (18.0%), and prostration (16.8%). Pallor (44.8%) and splenomegally (19.9%) were the most frequently detected physicalfindings. CONCLUSIONS: The HIV prevalence among malaria patients was not different from HIV prevalence in the general population. Further studies with carefully designed methodologies are recommended     

Effect of oral administration of aqueous whole extract of Cassytha filiformis on haematograms and plasma biochemical parameters in rats

Introduction

We evaluated the sub-chronic toxicity of the aqueous herbal extract prepared fromCassytha filiformis and administered daily for 28 days at dose levels (250, 500, and 1000 mg/kg bw) in male wistar albino rats. The LD₅₀ of the aqueous extract was determined.

Methods

The effects on body weights, organ weights, and certain haematological and plasma biochemical parameters were measured as indices of organ toxicity.

Results

The aqueous extract did not affect plasma glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT); however, a significant reduction in alkaline phosphatase (ALP) level occurred in all the treated groups. It also did not affect the electrolytes (Na+, Cl? and K+), total and direct bilirubin, creatinine, and glucose level. The aqueous extract elicited hypercholesterolaemic effects, but it did not affect the Hb, WBC, RBC, PVC, platelets, MCH, MCHC, MCV levels and differential counts (lympocytes, neutrophils, monocytes, eosinophils and basophils). It also reduced the body weight gain and absolute weight of the kidneys. The relative weights of the heart and lungs in some animal groups were equally reduced. The acute toxicological evaluation of the plant extract revealed an oral LD₅₀ value greater than 500 mg/kg bw.

Conclusion

This study suggests that aqueous extract ofC. filiformis administered at normal therapeutic doses is not likely to produce severe toxic effects on some organs or haematological and biochemical indices in rats.     

Advanced speckle tracking echocardiography allowing a three-myocardial layer-specific analysis of deformation parameters

AIMS: Different layers of myocardium may contribute differently to myocardial deformation. Speckle tracking based on high resolution two-dimensional (2D) echocardiography has been used to define myocardial deformation parameters of whole left ventricular (LV) segments. This study evaluated with a Novell analysis modality allowing layer-specific analysis of deformation if there are differences in myocardial deformation between different layers of myocardium. METHODS AND RESULTS: In 30 normal subjects and 20 patients with impaired myocardial function 2D parasternal short-axis echocardiographic views of the LV were acquired at the basal, mid-papillary, and apical levels. Using a Novell automatic frame-to-frame tracking system of natural acoustic echocardiographic markers (EchoPAC, GE Ultrasound, Haifa, Israel), circumferential strain (CS) and strain rate of the endocardial, mid-myocardial and epicardial layer was calculated for each LV segment in an 18-segment model. Wall motion for each segment was defined as normokinetic, hypokinetic, and akinetic based on 2D echocardiographic images. Peak systolic CS could be analysed in 837 segments (93%). In the normal subjects peak systolic CS was greatest in the endocardial layer, lower in the mid-myocardial layer, and lowest in the epicardial layer (38.1+/-9.0%, 28.9+/-9.3%, and 24.0+/-9.4%, respectively, P<0.001). In the patients with impaired LV function 151 segments were hypokinetic and 92 segments akinetic by visual analysis. In all myocardial layers peak systolic CS and strain rate decreased with decreasing segmental function. CONCLUSION: Decreasing myocardial deformation from endocardial to epicardial layers can be demonstrated with the use of an advanced analysis system allowing definition of deformation parameters for three myocardial layers. Myocardial deformation is reduced in all layers of segments with impaired wall motion.     

Prevalence of left ventricular diastolic dysfunction in newly diagnosed Nigerians with systemic hypertension: a pulsed wave Doppler echocardiographic study

Background

Systemic hypertension is a common cause of left ventricular diastolic dysfunction. However, its prevalence in Nigerians with untreated systemic hypertension is unknown.

Objective

To determine the prevalence of left ventricular diastolic dysfunction in newly diagnosed Nigerians with systemic hypertension using Doppler transmitral inflow and pulmonary venous flow velocities.

Methods

Two-dimensional echocardiography including Doppler was performed on 150 newly diagnosed cases of systemic hypertension and 150 normotensive controls. They were divided into hypertensives without left ventricular hypertrophy and those with left ventricular hypertrophy based on echocardiographically determined left ventricular mass index. Pulsed Doppler transmitral inflow and the pulmonary venous flow waves were used to categorise the patterns of diastolic dysfunction.

Results

The hypertensives and the normotensive controls were comparable in their baseline characteristics. The E/A ratio differed significantly between hypertensives with and without left ventricular hypertrophy and controls (1.00+0.30, 1.04±0.42, 1.33±0.27, p < 0.001). Left ventricular diastolic dysfunction occurred in 62% of systemic hypertension and 11.3% of the controls. Impaired relaxation was the commonest pattern (84.9%) of diastolic dysfunction.

Conclusion

Our study showed that left ventricular diastolic dysfunction is prevalent in Nigerians with newly diagnosed systemic hypertension and effort should be made to routinely screen for them.     

Opsonization of various capsular (K) E. coli by the alternative complement pathway

A virulence factor of E. coli K-1 is its capacity to avoid opsonization via the alternative complement pathway (ACP). Since it is not known if E. coli with other capsular (K) antigens have similar properties we examined various capsular E. coli for opsonization by the ACP. To assess opsonization we used whole blood luminol-dependent chemiluminescence (CL) and the magnesium salt of ethyleneglycol tetraacetic acid to block the classical pathway. E. coli K-types 6, 7, 27, 30, 42, 53, 57 and 75 were effectively opsonized via the ACP (greater than 65% of CL obtained with unchelated normal serum). K types 2 and 13 were opsonized by the ACP in both the high range greater than 65% and intermediate range 36-65%. Only K-types 1, 3, 5, 12 and 92 were poorly opsonized (less than 35%) by the ACP. The data demonstrate that most E. coli K-types were opsonized via the ACP. The poor opsonization of E. coli K3, 5, 12 and 92 by the ACP may be virulence factor for these bacteria.     

Clusters of eclampsia in a Nigerian teaching hospital.

OBJECTIVE: To describe the pattern of eclampsia between 1995 and 2004 at the Usmanu Danfodiyo University Teaching Hospital, Sokoto, northwestern Nigeria. STUDY DESIGN: A retrospective cohort of all deliveries and eclamptics seen from 1st January 1995 to 31st December 2004. Clusters of eclampsia were identified using purely temporal scan statistics. RESULTS: Of 15,318 deliveries during the period, 657(4.29%) had eclampsia. The yearly incidence of eclampsia at the beginning of the study period (1995) was 0.39% but this had increased to 7.0% in 2004 at a background exponential rate best described by quadratic curve fitting prediction model and a forecast curve that predicts an incidence of eclampsia of at least 32.4% of total deliveries by 2009. Temporal clusters occurred in 1996, 2001 and 2003-2004. CONCLUSION: The incidence of eclampsia is unusually high and is increasing. It has shown 3 clusters in the last 10 years.     

Urinary tract infection in severely malnourished children at the University of Maiduguri Teaching Hospital

One hundred and ninety-four children with severe protein energy malnutrition were investigated for urinary tract infection in this prospective study. The prevalence of urinary tract infection was found to be 11.3 per cent. There was no difference either between the sexes or the different categories of malnutrition. The commonest isolates were Gram-negative organisms predominantly Escherichia coli. The antibiotic sensitivity pattern of the organisms in this study differs from other reports. In this study, we observed poor sensitivities of organisms especially the Gram negatives to the second and third generation cephalosporins. We therefore conclude that regular surveillance of urinary tract infection pathogens and their antibiotic sensitivity patterns should be carried out.