Glycated nail proteins as a new biomarker in management of the South Kivu Congolese diabetics

Introduction: Diagnosis and monitoring of diabetes mellitus in sub-Saharan Africa, based on blood analyses, are hampered by infrastructural and cultural reasons. The first aim of this study was to evaluate the diagnostic accuracy of glycated nail proteins for diabetes mellitus. The second aim was to compare the course of short- and long-term glycemic biomarkers after 6 months of antidiabetic treatment. These objectives should support our hypothesis that glycated nail proteins could be used as an alternative glycemic biomarker. Materials and methods: This case-control study consisted of 163 black diabetics and 67 non-diabetics of the South Kivu (Democratic Republic of Congo). Diagnostic accuracy of glycated nail proteins was evaluated using ROC curve analysis. At the start of the study, glycated nail protein concentrations were compared between diabetics and non-diabetics, using a nitro blue tetrazolium (NBT) colorimetric method. In a subgroup of 30 diabetics, concentrations of glycated nail proteins, fasting glucose (Accu-Chek® Aviva), serum fructosamine (NBT) and HbA1c (DCA-2000+®) were measured at start and after 6 months. Results: ROC analysis yielded an AUC of 0.71 (95% confidence interval (CI): 0.65-0.76) and a cut-off point of 3.83 µmol/g nail. Concentration of glycated nail proteins was significantly higher (P < 0.001) in diabetics in comparison with non-diabetics. After 6 months of antidiabetic treatment, a significant drop in the fasting glucose concentration (P = 0.017) and concentration of glycated nail proteins (P = 0.008) was observed in contrast to serum fructosamine and HbA1c. Conclusions: Measurement of glycated nail proteins could be used to diagnose and monitor diabetes mellitus in sub-Saharan Africa

Whole blood Fe isotopic signature in a sub-Saharan African population

The Fe isotopic composition of an individual's whole blood has recently been shown to be an interesting clinical indicator of Fe status. The present study aimed to evaluate the influence of several endemic characteristics of a representative population of the South Kivu province, an Fe-rich volcanic African region, on the whole blood Fe isotopic composition. Both diabetes mellitus and the ferroportin Q248H mutation are very common in Africa and are strongly associated with impairments in Fe metabolism. Fe isotopic analysis of whole blood samples was carried out using multi-collector inductively coupled plasma-mass spectrometry (after chromatographic isolation of the target element). Forty-two male subjects (between 48 and 59 years old) living in Bukavu (South Kivu) were enrolled in this study. Among the selected population, wild-type subjects and subjects presenting the ferroportin Q248H mutation (heterozygotes and homozygotes) were included. Within each group, diabetic and non-diabetic patients were considered. The whole blood delta Fe-56 value ranged from -3.09% to -2.41%. The delta Fe-56 value shows a significant negative correlation with the ferritin concentration. No correlation could be established between the whole blood delta Fe-56 value and the transferrin concentration, transferrin saturation or serum Fe concentration. The ferroportin Q248H mutation did not seem to have affected the whole blood Fe isotopic signature. The whole blood delta Fe-56 values were significantly higher in diabetic subjects than in non-diabetic subjects and showed a significant negative correlation with body mass index (BMI) values

Diabetes mellitus and laboratory medicine in sub-Saharan Africa : challenges and perspectives

Diabetes mellitus is an increasing public health problem in sub-Saharan Africa with a substantial socioeconomic burden. Although laboratory medicine has been recognized as one of the six key public health functions, there are still gaps in strengthening of laboratory services in developing countries. In the last decades, a lot of progress has been made in the diagnostic field of infectious diseases, whereas the diagnosis of noncommunicable diseases is still insufficient and uneven. This article analyses the challenges encountered in diagnosing and monitoring of diabetes mellitus in sub-Saharan Africa and explores new alternative diagnostic tools

The presence of fructosamine in human aortic valves is associated with valve stiffness

AIMS: Human heart valves are prone to glycation, a fundamental process of ageing. The aim of this study was to establish the relationship between fructosamine formation and the mechanical properties of human aortic valves. METHODS: 67 patients (age: 76±8 years) diagnosed with an aortic valve stenosis, who underwent an aortic valve replacement were enrolled. Fructosamine and calcium concentrations in aortic valves were determined. Using a transthoracic Doppler echocardiography, aortic valve orifice area and transvalvular pressure gradients were measured. In a subgroup of 32 patients, the aortic valve orifice area was sufficient to carry out mechanical testing on a LFPlus Universal material tester. An in vitro removal of fructosamine of the valve was initiated using ATP-dependent fructosamine 3-kinase (FN3K). RESULTS: A significant correlation was found between the aortic valve fructosamine concentration and the calculated aortic valve orifice area: Y (aortic valve orifice area, mm2)=1.050-0.228X (aortic valve fructosamine concentration, µmol/g valve) (r=-0.38). A significantly higher calcium concentration was measured in the aortic valves of diabetics in comparison with those of non-diabetics. A multiple regression analysis revealed that the presence of diabetes mellitus and aortic valve fructosamine concentration were the main predictors of the extensibility of the aortic valves. In the in vitro deglycation study, a significant lower aortic valve fructosamine concentration was detected after treatment with FN3K. This resulted in an increased flexibility of the aortic valves. CONCLUSIONS: Although no direct causativeness is proven with the presented results, which just show an association between fructosamine, the effect of FN3K and aortic valve stiffness, the present study points for the first time towards a possible additional role of the Amadori products in the biomechanical properties of ageing aortic valves

Association between post-traumatic stress disorder and hypertension in Congolese exposed to violence: a case-control study.

Numerous risk factors have been involved in the pathogenesis of hypertension. The contribution of psychological factors, including post-traumatic stress disorder, remains largely underexplored, despite their potential role in hypertension. We compared the prevalence of trauma, post-traumatic stress and other psychological disorders between hypertensive and normotensive patients from Bukavu (Democratic Republic of Congo), a 25-year war-exposed city. In this case-control study, we assessed past traumatic events with the Stressful-Events-Scale, post-traumatic stress disorder through the post-traumatic diagnostic scale, depression and alcohol use disorder through the MINI-International-Neuropsychiatric-Interview, and emotion regulation through the Emotion-Regulation-Questionnaire in 106 hypertensive and 106 normotensive patients, enrolled at the Bukavu General Hospital. Compared with normotensive controls (73% women, age: 43 ± 14 years, BP: 121 ± 10/75 ± 8 mmHg), hypertensive patients (57% women, age: 42 ± 13 years, BP: 141 ± 12/82 ± 7 mmHg, on a median of two antihypertensive drugs) were exposed to more man-made traumas (61 vs. 13%, P &lt; 0.001), used more expressive suppression (P = 0.05) and less cognitive reappraisal (P = 0.02) as emotional regulation strategies. They developed more frequent post-traumatic stress disorder (36 vs. 7%, P &lt; 0.001) and major depressive disorder (37 vs. 13%, P = 0.001), often in association with alcohol use disorder (23 vs. 4%, P &lt; 0.001). In multivariate logistic regression, post-traumatic stress disorder [OR = 3.52 (1.23-6.54)], man-made trauma [OR = 2.24 (1.15-4.12)], family history of hypertension [OR = 2.24 (1.06-4.44)], fasting blood glucose [OR = 1.85 (1.07-3.08)], BMI [OR = 1.28 (1.12-2.92)], expressive suppression [OR = 1.23 (1.11-2.23)] and cognitive reappraisal [OR = 0.76 (0.63-0.98)] were independent predictors of hypertension. In Congolese populations exposed to war, man-made trauma exposure and post-traumatic stress disorder appear to be more tightly related to hypertension than classical hypertension risk factors

Additional file 1 of The effect of COVID-19 on the non-COVID health outcomes of crisis-affected peoples: a systematic review

Supplementary Material

A simple colorimetric assay for measuring fructosamine 3 kinase activity

Background: Fructosamine 3 kinase (FN3K) is a deglycating enzyme, which may play a key role in reducing diabetes- induced organ damage by removing bound glucose from glycated proteins. We wanted to develop a simple colorimetric method for assaying FN3K activity in human body fluids. Methods: Glycated bovine serum albumin (BSA) was obtained by glycation with a 10% glucose solution at 37 degrees C. After 72 h, glycated BSA was dialyzed against phosphate buffered saline (0.1 mol/L, pH 7.4). The dialyzed solution (containing +/- 1000 mu mol/L fructosamine) was used as an FN3K substrate. In the assay, 300 mu L of substrate was incubated with 50 mu L of serum and 100 mu L of MgCl 2 (0.7 mmol/L)/ATP (3.2 mmol/L). The fructosamine concentration was determined at the start and after incubation (120 min, 25 degrees C). The decrease in fructosamine concentration over time is a measure for the FN3K activity (1 U corresponding to 1 mu mol/min). Concomitantly, the FN3K SNP rs1056534 and the ferroportin SNP rs1156350 were genotyped. Results: Within-assay CV was 6.0%. Reference values for FN3K activity in serum were 14.2 +/- 1.6 U/L (n = 143). Reference values for FN3K were neither age-nor sex-dependent. The various FN3K SNP rs1056534 genotypes showed no significant differences in serum FN3K activity. In diabetics (n = 191), values (14.0 +/- 2.2 U/L) were comparable to those of the controls. FN3K activity in erythrocytes was significantly higher (170.3 +/- 7.6 U/L). The intra-erythrocytic FN3K activity makes the results prone to hemolysis. FN3K activity depended on the ferroportin Q248H genotypes, with the highest value for the wild type genotype. Neither transferrin saturation nor ferritin were confounders for the FN3K activity. FN3K activity was significantly (p < 0.0001) correlated with HbA(1c) values, although the correlation between FN3K and HbA(1c) was weak. Conclusions: The simple colorimetric method allows determining FN3K activity in human serum. The assay may be useful for studying the impact of deglycation processes in diabetes mellitus

Challenges with Achieving and Maintaining High Oral Cholera Vaccine Coverage in Uvira, The Democratic Republic of the Congo: serial cross-sectional representative surveys

Background Maximizing the impact of the limited global supply of killed oral cholera vaccines (kOCVs) requires understanding the barriers to achieving high population coverage during vaccination campaigns as well as factors that may influence coverage declines over time. In 2020, two rounds of mass vaccination campaigns with Euvichol-Plus were conducted in Uvira in The Democratic Republic of the Congo. We used data from three serial cross-sectional representative surveys conducted between 11 and 33 months after vaccination to:(i) estimate the post-vaccination campaign coverage and explore heterogeneity by geographic and demographic factors; (ii) examine barriers and facilitators of vaccine uptake; and (iii) to describe the changes in coverage over time and predict future coverage. Methods We collected data on socio-demographics, self-reported vaccination status, population movement, and knowledge, attitudes, and behaviors related to kOCVs using household surveys. We performed descriptive analyses comparing characteristics between vaccinated and unvaccinated individuals and explored the potential role of population movement as a cause for low coverage. We used an exponential decay model to predict the proportion of the population vaccinated with at least one dose of kOCV over time based on age-specific coverage in each cross-sectional survey. Results We enrolled 8,735 participants from 1,433 households across the three surveys. Coverage in survey round 1 was 55% for &gt;1 dose of kOCV (95% CI: 51-60) and 23% &gt; 2 doses (95% CI: 20-27). Vaccine refusal was associated with lack of confidence in vaccine safety and 29% of unvaccinated adults reported it was unlikely they would accept kOCVs if an additional mass vaccination campaign was conducted in their area. Coverage of at least one dose of kOCV declined on average by 17% per year (95% Credible Interval: 8 – 26) and was 39% (95% CI: 36-43) by survey round 3 (32.5 - 33.2 months after 2nd dose campaign). Conclusions We estimate that more than half of the target population in Uvira was not fully vaccinated against cholera and that population-level coverage declined rapidly over the years post-vaccination. In settings like Uvira, even if direct protection from the vaccine is durable for 5 or more years, migration can lead to a rapid decline in effective population-level coverage and reduce the indirect protection from the vaccine. Our findings suggest that vaccine coverage dilution may be reduced by more frequent and coordinated geographic vaccination efforts