Background: In the midst of the COVID-19 pandemic, to palliate to the lockdown and cover academic programs, the Faculty of Medicine and Pharmaceutical Sciences of the University of Dschang (FMPS-UDs) in Cameroon has implemented e-learning... more
Background: In the midst of the COVID-19 pandemic, to palliate to the lockdown and cover academic programs, the Faculty of Medicine and Pharmaceutical Sciences of the University of Dschang (FMPS-UDs) in Cameroon has implemented e-learning using WhatsApp®. We aimed to describe the opinion of students and lecturers about it after its implementation at the FMPS-UDs.Methods: We designed a uniform scheme to teach using WhatsApp® during the university lock-down, and both the students and the teaching staff of the FMPS-UDs received clear information on the implementation. At the end of the online-teaching period of two and a half months prior to the reopening of the university, we surveyed our students and teaching staff. Sociodemographic characteristics and opinions about e-learning were collected using a standard questionnaire. Results: We enrolled 229 students and 40 lecturers of the FMPS-UDs. Students reported a poorer internet connection (p<0.001, p-homogeneity< 0.001) despite a...
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Despite some cases of severe or critical manifestations of the coronavirus disease 2019 (COVID-19) described among children, the prevalence of this infection in the pediatric population is quite low worldwide, particularly in sub-Saharan... more
Despite some cases of severe or critical manifestations of the coronavirus disease 2019 (COVID-19) described among children, the prevalence of this infection in the pediatric population is quite low worldwide, particularly in sub-Saharan Africa. Current data suggest indeed that, independent of the population considered overall, severe and critical cases of COVID-19 are rare among children. This observation prompted us to discuss the possible hypotheses which could explain the low prevalence of COVID-19 among children; amongst others, we discuss (1) immunomodulation by the Bacillus Calmette–Guerin vaccine or by some parasitic infections such as malaria, schistosomiasis, and helminthiasis and (2) cross immunization with other coronaviruses commonly found in the sub-Saharan African setting.
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Background In the midst of the COVID-19 pandemic, to palliate to the lockdown and cover academic programs, the faculty of medicine and pharmaceutical sciences (FMPS) of the university of Dschang (UDs) in Cameroon has implemented... more
Background In the midst of the COVID-19 pandemic, to palliate to the lockdown and cover academic programs, the faculty of medicine and pharmaceutical sciences (FMPS) of the university of Dschang (UDs) in Cameroon has implemented e-learning using WhatsApp®. Aim Describe the opinion of students and lecturers after its implementation of e-learning at the FMPS of UDs. Methods We designed a uniform teaching scheme using WhatsApp® during the university lockdown. Students and members of the teaching staff of the FMPS of UDs were enrolled after receiving clear information on the study implementation. At the end of the online-teaching period of two and a half months, we surveyed our students and teaching staff. Sociodemographic characteristics and opinions about e-learning were collected using a standard questionnaire. Results We enrolled 229 students and 40 lecturers of the FMPS. Students reported a decremented quality of internet connection (p < 0.001, p-homogeneity < 0.001) despite ...
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This study aimed to assess the effects of non-surgical periodontal treatment (NSPT) of chronic periodontitis on insulin sensitivity, glucose tolerance, and serum C reactive protein (CRP) level in individuals without diabetes. Twenty... more
This study aimed to assess the effects of non-surgical periodontal treatment (NSPT) of chronic periodontitis on insulin sensitivity, glucose tolerance, and serum C reactive protein (CRP) level in individuals without diabetes. Twenty individuals without diabetes with chronic periodontitis underwent NSPT, which consisted of complete scaling, polishing, root planing, and irrigation of the periodontal pockets with a 10% povidone-iodine solution. Periodontal indices (plaque index, gingival bleeding index, pocket depth, and clinical attachment loss), insulin sensitivity using the Short Insulin Tolerance Test index (KITT), glucose tolerance derived from oral glucose tolerance test, and serum CRP level were measured before and 3 months after the intervention. This study was carried out at the National Obesity Center of Yaoundé Central Hospital, Cameroon. After 3 months, we observed significant improvement in periodontal parameters (all p<0.001) and insulin sensitivity (3.72 (2.99–4.17) %...
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In a systematic review, the authors explored genetic association studies of essential hypertension in African populations. Studies reporting on the association of polymorphism(s) with hypertension in African populations were included.... more
In a systematic review, the authors explored genetic association studies of essential hypertension in African populations. Studies reporting on the association of polymorphism(s) with hypertension in African populations were included. Appropriate studies were pooled using random effects model meta-analysis, under six potential inheritance models. In all, 46 polymorphisms in 33 genes were investigated for their association with hypertension or blood pressure levels. Meta-analysis was possible for three single nucleotide polymorphisms: rs4340, rs699, and rs5186. An association was found between rs5186, rs699, and hypertension under allele contrast and homozygous codominant models (odds ratio, 1.63 [95% confidence interval, 1.04-2.54] and 4.01 [95% confidence interval, 1.17-13.80] for rs5186, respectively; and 1.80 [95% confidence interval, 1.13-2.87] for rs699). Findings were mostly robust in sensitivity analyses. According to the systematic review, there is currently insufficient evi...
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The burden of dyslipidaemia in Africa remains inadequately characterised. We aimed to estimate the prevalence of dyslipidaemia in African adults from hospital-based and community-based studies. In this systematic review and meta-analysis,... more
The burden of dyslipidaemia in Africa remains inadequately characterised. We aimed to estimate the prevalence of dyslipidaemia in African adults from hospital-based and community-based studies. In this systematic review and meta-analysis, we searched MEDLINE via PubMed, Embase, African Journals Online, and African Index Medicus for studies published between Jan 1, 1980, and July 31, 2017, without language restriction. We assessed methodological quality of all cross-sectional studies reporting on the prevalence of elevated concentrations of total cholesterol, LDL cholesterol, or triglycerides, or low concentrations of HDL cholesterol in adults residing in African countries. We excluded reports on Africans living outside Africa, studies of individuals selected on the basis of existing dyslipidaemia or those including children and adolescents, and case series with a small sample size. The most frequently used cutoffs in the included studies were chosen for the subgroup analysis. We use...
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Congenital heart disease (CHD) is a common condition in children in Sub-Saharan Africa (SSA), where it is associated with poor outcomes. Diagnosis of CHD in SSA depends essentially on echocardiography, which is available only in few urban... more
Congenital heart disease (CHD) is a common condition in children in Sub-Saharan Africa (SSA), where it is associated with poor outcomes. Diagnosis of CHD in SSA depends essentially on echocardiography, which is available only in few urban referral centers. Our aim was to assess time changes in the pattern of referral for pediatric echocardiography and the subsequent diagnosis of structural CHD in a major SSA city. All pediatric echocardiography performed between 2004 and 2013 at the echocardiography laboratory of the Yaounde General Hospital were reviewed. The primary indication of the study and the presence of structural CHD were recorded. Between 2004 and 2013, 9,390 echocardiograms were performed and 834 (8.9%) children aged 1 day to 15 years underwent echocardiography at the center, and 227 (27.2%) cases of definite structural CHD were diagnosed, with 123 (54.2%) in boys. The most frequent indications for echocardiography were heart murmurs (40%) and the suspicion of CHD (37.4%)...
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Fructosamine is a marker of glucose control reflecting the average glycaemic level over the preceding 2-3 weeks. Fructosamine has not gained as much popularity as glycated haemoglobin (HbA1c) for diabetes mellitus (DM) control monitoring,... more
Fructosamine is a marker of glucose control reflecting the average glycaemic level over the preceding 2-3 weeks. Fructosamine has not gained as much popularity as glycated haemoglobin (HbA1c) for diabetes mellitus (DM) control monitoring, and the related underlying reasons remain unclear. We aim to search for and summarise available evidence on the accuracy of fructosamine measurements to diagnose and monitor DM. This systematic review will include randomised control trials, controlled before-and-after studies, time series designs, cohort studies, case-control studies and cross-sectional surveys reporting the diagnosis and/or monitoring of DM (type 1 DM, type 2 DM and gestational DM) with fructosamine compared with other measures of glycaemia (fasting glucose, oral glucose tolerance test, random glucose, HbA1c), without any language restriction. We will perform electronic searches in PubMed, Scopus and other databases, supplemented with manual searches. Articles published from 1 Jan...
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Research Interests: Biomarkers, Cameroon, Medicine, Humans, Diabetes mellitus, and 15 moreFemale, Point of Care, Male, Aged, Middle Aged, Adult, Altitude, Point of Care Testing, Cross Sectional Studies, Equipment Design, Predictive value of tests, Glycated hemoglobin, Case Control Studies, Analyser, and Medical and Health Sciences
We aimed to evaluate the predictive utility of common fasting insulin sensitivity indices, and non-laboratory surrogates [BMI, waist circumference (WC) and waist-to-height ratio (WHtR)] in sub-Saharan Africans without diabetes. We... more
We aimed to evaluate the predictive utility of common fasting insulin sensitivity indices, and non-laboratory surrogates [BMI, waist circumference (WC) and waist-to-height ratio (WHtR)] in sub-Saharan Africans without diabetes. We measured fasting glucose and insulin, and glucose uptake during 80/mU/m2/min euglycemic clamp in 87 Cameroonians (51 men) aged (SD) 34.6 (11.4) years. We derived insulin sensitivity indices including HOMA-IR, quantitative insulin sensitivity check index (QUICKI), fasting insulin resistance index (FIRI) and glucose-to-insulin ratio (GIR). Indices and clinical predictors were compared to clamp using correlation tests, robust linear regressions and agreement of classification by sex-specific thirds. The mean insulin sensitivity was M = 10.5 ± 3.2 mg/kg/min. Classification across thirds of insulin sensitivity by clamp matched with non-laboratory surrogates in 30-48% of participants, and with fasting indices in 27-51%, with kappa statistics ranging from -0.10 t...
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Research Interests: Cameroon, Medicine, Therapeutic drug monitoring, Humans, Hyperglycemia, and 15 moreBlood Glucose, Insulin, Female, Male, Resource Limitation, Length of Stay, Clinical Sciences, Middle Aged, Retrospective Studies, Emergencies, Fluid Therapy, Diabetic ketoacidosis, Clinical Protocols, Ketone Bodies, and Medical Audit
several biomarkers were proposed to detect pancreatic beta cell destruction in vivo but were so far not compared for sensitivity and significance. we used islet transplantation as model to compare plasma concentrations of miR-375, GAD65... more
several biomarkers were proposed to detect pancreatic beta cell destruction in vivo but were so far not compared for sensitivity and significance. we used islet transplantation as model to compare plasma concentrations of miR-375, GAD65 and (un)methylated insulin DNA, measured at subpicomolar sensitivity, to study their discharge kinetics, power for outcome prediction and detection of graft loss during follow-up. at 60 min post-transplantation, GAD65 and miR-375 consistently showed near-equimolar and correlated increases, proportional to the number of implanted beta cells. GAD65 and miR-375 showed comparable power to predict poor graft outcome at 2 months, with AUC respectively of 0.833 and 0.771 (p=0.53). Using ROC analysis we defined likelihood ratios (LRs) for rationally selected result intervals: in GADA-negative recipients (N=28), GAD65 <4.5 pmol/l (LR=0.15) and >12.2 pmol/l (LR=∞) respectively predicted good and poor outcome. miR-375 could be used in all recipients irres...
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We investigated the effect of HLA class I risk alleles on disease progression in various phases of subclinical islet autoimmunity in first-degree relatives of patients with type 1 diabetes. A registry-based group of siblings/offspring... more
We investigated the effect of HLA class I risk alleles on disease progression in various phases of subclinical islet autoimmunity in first-degree relatives of patients with type 1 diabetes. A registry-based group of siblings/offspring (aged 0-39 years) was monitored from single- to multiple-autoantibody positivity (= 267) and from multiple-autoantibody positivity to clinical onset (= 252) according to,,andstatus. Genetic markers were determined by PCR sequence-specific oligotyping. Unlikeor,associated with delayed progression from single- to multiple-autoantibody positivity (= 0.009) but not to type 1 diabetes. This occurred independently from older age (< 0.001) and absence ofor< 0.001 and= 0.003, respectively), and only in the presence of GAD autoantibodies. In contrast,associated with accelerated progression from multiple-autoantibody positivity to clinical onset (= 0.006), but its effects were restricted torelatives with IA-2- or zinc transporter 8 autoantibodies (= 0.002)...
Research Interests: Immunology, Autoimmunity, Adolescent, Humans, Child, and 15 moreFemale, Male, Infant, Genotype, Adult, Disease Progression, Diabetes Care, Autoantibodies, Médecine Interne, islets of Langerhans, Insulin antibodies, Child preschool, endocrinologie, Human leukocyte antigen, and Genetic predisposition to disease
Insulin autoantibodies (IAA) are often the first marker of autoimmunity detected in children in the preclinical phase of type 1 diabetes (T1D). Currently, the vast majority of laboratories adopt the radiobinding micro-assay (RBA) for... more
Insulin autoantibodies (IAA) are often the first marker of autoimmunity detected in children in the preclinical phase of type 1 diabetes (T1D). Currently, the vast majority of laboratories adopt the radiobinding micro-assay (RBA) for measuring IAA. Our aim was to replace RBA with a novel non-radioactive IAA Luciferase Immuno Precipitation System (LIPS) assay with improved performance. We developed (pro)insulin antigens with alternative placements of a NanoLuc™ luciferase reporter (NLuc). Performance in LIPS was evaluated by testing sera from new onset T1D (n = 80), blood donors (n = 123), schoolchildren (n = 186), first-degree relatives (FDRs) from the Bart's Oxford family study (n = 53) and from the Belgian Diabetes Registry (n = 136), coded sera from the Islet Autoantibody Standardization Program (IASP) (T1D n = 50, blood donors n = 90). IAA LIPS based on B chain-NLuc proinsulin or B chain-NLuc insulin, in which NLuc was fused at the C-terminus of the insulin B chain, required...
Research Interests: Biomarkers, Prediction, Type 2 Diabetes, Medicine, Humans, and 15 moreChild, Insulin, Immunoprecipitation, Clinical Sciences, Prognosis, Immunoassay, LIPs, Sensitivity and Specificity, Type 2 Diabetes Mellitus, Predictive value of tests, Autoantibodies, Case Control Studies, Insulin antibodies, fluorescent dyes, and proinsulin
We investigated whether islet autoantibody profile, HLA-DQ genotype, and age influenced a 20-year progression to diabetes from first autoantibody positivity (autoAb(+)) in first-degree relatives of patients with type 1 diabetes.... more
We investigated whether islet autoantibody profile, HLA-DQ genotype, and age influenced a 20-year progression to diabetes from first autoantibody positivity (autoAb(+)) in first-degree relatives of patients with type 1 diabetes. Persistently islet autoAb(+) siblings and offspring (n = 462) under 40 years of age were followed by the Belgian Diabetes Registry. AutoAbs against insulin (IAA), GAD (GADA), IA-2 antigen (IA-2A), and zinc transporter 8 (ZnT8A) were determined by radiobinding assay. The 20-year progression rate of multiple-autoAb(+) relatives (n = 194) was higher than that for single autoAb(+) participants (n = 268) (88% vs. 54%; P < 0.001). Relatives positive for IAA and GADA (n = 54) progressed more slowly than double-autoAb(+) individuals carrying IA-2A and/or ZnT8A (n = 38; P = 0.001). In multiple-autoAb(+) relatives, Cox regression analysis identified the presence of IA-2A or ZnT8A as the only independent predictors of more rapid progression to diabetes (P < 0.001...
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The hyperglycemic clamp test, the gold standard of beta cell function, predicts impending type 1 diabetes in islet autoantibody-positive individuals, but the latter may benefit from less invasive function tests such as the... more
The hyperglycemic clamp test, the gold standard of beta cell function, predicts impending type 1 diabetes in islet autoantibody-positive individuals, but the latter may benefit from less invasive function tests such as the proinsulin:C-peptide ratio (PI:C). The present study aims to optimize precision of PI:C measurements by automating a dual-label trefoil-type time-resolved fluorescence immunoassay (TT-TRFIA), and to compare its diagnostic performance for predicting type 1 diabetes with that of clamp-derived C-peptide release. Between-day imprecision (n = 20) and split-sample analysis (n = 95) were used to compare TT-TRFIA (AutoDelfia, Perkin-Elmer) with separate methods for proinsulin (in-house TRFIA) and C-peptide (Elecsys, Roche). High-risk multiple autoantibody-positive first-degree relatives (n = 49; age 5-39) were tested for fasting PI:C, HOMA2-IR and hyperglycemic clamp and followed for 20-57 months (interquartile range). TT-TRFIA values for proinsulin, C-peptide and PI:C co...
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We investigated whether HLA-A*24 typing complements screening for HLA-DQ and for antibodies (Abs) against insulin, GAD, IA-2 (IA-2A), and zinc transporter-8 (ZnT8A) for prediction of rapid progression to type 1 diabetes (T1D).... more
We investigated whether HLA-A*24 typing complements screening for HLA-DQ and for antibodies (Abs) against insulin, GAD, IA-2 (IA-2A), and zinc transporter-8 (ZnT8A) for prediction of rapid progression to type 1 diabetes (T1D). Persistently Ab+ siblings/offspring (n = 288; aged 0–39 years) of T1D patients were genotyped for HLA-DQA1-DQB1 and HLA-A*24 and monitored for development of diabetes within 5 years of first Ab+. HLA-A*24 (P = 0.009), HLA-DQ2/DQ8 (P = 0.001), and positivity for IA-2A ± ZnT8A (P < 0.001) were associated with development of T1D in multivariate analysis. The 5-year risk increased with the number of the above three markers present (n = 0: 6%; n = 1: 18%; n = 2: 46%; n = 3: 100%). Positivity for one or more markers identified a subgroup of 171 (59%) containing 88% of rapid progressors. The combined presence of HLA-A*24 and IA-2A+ ± ZnT8A+ defined a subgroup of 18 (6%) with an 82% diabetes risk. Among IA-2A+ ± ZnT8A+ relatives, identification of HLA-A*24 carriers...
Research Interests: Diabetes, Biology, Adolescent, Medicine, Humans, and 15 moreChild, Internal Medicine, Diabetes mellitus, Female, Male, First Degree Relatives, Young Adult, Risk factors, Risk Factors, Autoantibodies, Médecine Interne, endocrinologie, Human leukocyte antigen, Medical and Health Sciences, and Genetic predisposition to disease
Summary In first-degree relatives of type 1 diabetic patients, we investigated whether diabetes risk assessment solely based on insulinoma antigen 2 (IA-2) and zinc transporter 8 (ZnT8) antibody status (IA-2A, respectively, ZnT8A) is as... more
Summary In first-degree relatives of type 1 diabetic patients, we investigated whether diabetes risk assessment solely based on insulinoma antigen 2 (IA-2) and zinc transporter 8 (ZnT8) antibody status (IA-2A, respectively, ZnT8A) is as effective as screening for three or four autoantibodies [antibodies against insulin (IAA), glutamate decarboxylase 65 kDa (GAD) glutamate decarboxylase autoantibodies (GADA) and IA-2A with or without ZnT8A] in identifying children, adolescents and adults who progress rapidly to diabetes (within 5 years). Antibodies were determined by radiobinding assays during follow-up of 6444 siblings and offspring aged 0–39 years at inclusion and recruited consecutively by the Belgian Diabetes Registry. We identified 394 persistently IAA+, GADA+, IA-2A+ and/or ZnT8A+ relatives (6·1%). After a median follow-up time of 52 months, 132 relatives developed type 1 diabetes. In each age category tested (0–9, 10–19 and 20–39 years) progression to diabetes was significantl...
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Context and Objective: In preparation of future prevention trials, we aimed to identify predictors of 3-year diabetes onset among oral glucose tolerance test (OGTT)- and hyperglycemic clamp-derived metabolic markers in persistently islet... more
Context and Objective: In preparation of future prevention trials, we aimed to identify predictors of 3-year diabetes onset among oral glucose tolerance test (OGTT)- and hyperglycemic clamp-derived metabolic markers in persistently islet autoantibody positive (autoAb+) offspring and siblings of patients with type 1 diabetes (T1D). Design: The design is a registry-based study. Setting: Functional tests were performed in a hospital setting. Participants: Persistently autoAb+ first-degree relatives of patients with T1D (n = 81; age 5–39 years). Main Outcome Measures: We assessed 3-year predictive ability of OGTT- and clamp-derived markers using receiver operating characteristics (ROC) and Cox regression analysis. Area under the curve of clamp-derived first-phase C-peptide release (AUC5–10min; min 5–10) was determined in all relatives and second-phase release (AUC120–150min; min 120–150) in those aged 12–39 years (n = 62). Results: Overall, the predictive ability of AUC5–10min was bette...
Research Interests: Adolescent, Medicine, Humans, Child, Internal Medicine, and 15 moreInsulin, Diabetes mellitus, Female, Male, Clinical Sciences, Adult, Medicine and Health Sciences, Glucose Tolerance Test, Glucose Intolerance, Autoantibodies, Child preschool, mellitus, C Peptide, High risk, and Paediatrics and reproductive medicine
PRISMA-P checklist. This document shows where the different items required in the PRISMA guidelines for protocols appear in the present document. (DOCX 24 kb)
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OBJECTIVE Immune intervention trials in recent-onset type 1 diabetes would benefit from biomarkers associated with good therapeutic response. In the previously reported randomized placebo-controlled anti-CD3 study (otelixizumab;... more
OBJECTIVE Immune intervention trials in recent-onset type 1 diabetes would benefit from biomarkers associated with good therapeutic response. In the previously reported randomized placebo-controlled anti-CD3 study (otelixizumab; GlaxoSmithKline), we tested the hypothesis that specific diabetes autoantibodies might serve this purpose. RESEARCH DESIGN AND METHODS In the included patients (n = 40 otelixizumab, n = 40 placebo), β-cell function was assessed as area under the curve (AUC) C-peptide release during a hyperglycemic glucose clamp at baseline (median duration of insulin treatment: 6 days) and every 6 months until 18 months after randomization. (Auto)antibodies against insulin (I[A]A), GAD (GADA), IA-2 (IA-2A), and ZnT8 (ZnT8A) were determined on stored sera by liquid-phase radiobinding assay. RESULTS At baseline, only better preserved AUC C-peptide release and higher levels of IAA were associated with better preservation of β-cell function and lower insulin needs under anti-CD3...