Tropical Forest Canopy Height and Aboveground Biomass Estimation Using Airborne Lidar and Landsat-8 Data, a Sensitivity Study with Respect to Landsat-8 Data Temporal Availability, in Mai Ndombe Province, Democratic Republic of Congo

Tropical forests’ structure information, such as forest canopy height, is a key component in any estimate of carbon stock. Tropical rainforests constitute the most forested ecosystems that harbor the largest biodiversity on Earth and store more carbon (above and belowground biomass) than any other ecosystem in the world. However, estimates of forest canopy structure is lacking over most of the regions that host this ecosystem because of both the structure’s complexity of this ecosystems and the incomplete or lack of up-to-date national forest inventory data necessary to derive forest canopy height and aboveground biomass. This study explores the capability of Landsat-8 imagery to predict dominant forest canopy height and aboveground biomass in Mai Ndombe province, Democratic Republic of Congo – a country that host half of the Congo Basin forests – within the context of the temporal availability of Landsat-8 imagery. A random forest regression model was used to predict dominant forest canopy height at 30 m spatial resolution from (a) only the July 14th 2013 (dry season) Landsat-8 image, (b) only the December 8th 2014 (wet season) Landsat-8 image, and (c) both images. The accuracy of the random forest regression model was performed on test data (n=2639) resulting in a, for the best prediction when using both dates together, RMSE = 3.84 m, R2 = 0.47. The model was then applied to the study area to derive forest canopy height using predictor variables from (a) only the dry season, (b) only the wet season, and (c) both images. The allometry equation defined by Xu et al. (2017) was used to generate aboveground biomass maps from (a) only the July 14th 2013 (dry season) Landsat-8 image, (b) only the December 8th 2014 (wet season) Landsat-8 image, and (c) both images using the study area forest canopy height maps. Field plots of aboveground biomass measurements were compared to predicted aboveground biomass maps for validation purpose. Validation process revealed a better prediction of aboveground biomass (RMSE= 83.77 Mg.ha-1) when the forest canopy height maps derived with both images was used to estimate aboveground biomass

Anthropogenic Land Use Change and Adoption of Climate Smart Agriculture in Sub-Saharan Africa

Compelling evidence in Sub-Saharan Africa (SSA) shows that Climate-Smart Agriculture (CSA) has a positive impact on agricultural productivity. However, the uptake of CSA remains low, which is related to anthropogenic, or human-related, decisions about CSA and agricultural land use. This paper assesses households’ decisions to allocate agricultural land to CSA technologies across space and over time. We use the state-contingent theory, mixed methods, and mixed data sources. While agricultural land is increasing, forest land is decreasing across countries in SSA. The results show that household decisions to use CSA and the extent of agricultural land allocation to CSA remain low with a negative trend over time in SSA. Owned land and accessing land through rental markets are positively associated with allocating land to CSA technologies, particularly where land pressure is high. Regarding adaptation, experiencing rainfall shocks is significantly associated with anthropogenic land allocation to CSA technologies. The country policy assessment further supports the need to scale up CSA practices for adaptation, food security, and mitigation. Therefore, scaling up CSA in SSA will require that agriculture-related policies promote land tenure security and land markets while promoting climate-smart farming for food security, adaptation, and mitigation

Profil de sensibilisation aux allergènes des asthmatiques adultes à Kinshasa, RDC : Etude transversale par prick-tests: Allergen sensitization profile of adult asthmatics in Kinshasa, DRC: Cross-sectional study by prick-tests

Context. Atopy is a common feature of asthma, involving near 80% of patients. Allergen sensitization shows environmental and geographical variability worldwide. Objective. To determine the common allergen sensitization profile of adult asthmatics in Kinshasa. Methods. From June 2017 to February 2018, 216 asthmatics aged 18 and over, of both sexes, were consecutively recruited at the University Clinics of Kinshasa and in some parishes and churches around the same town. The socio-demographic variables were registered using a validated questionnaire. The prick-test was performed relaying on five standardized commercial extracts of dog and cat dander, house dust mite (Blomia tropicalis, Bt), molds (Alternaria alternata), and egg yolk. Results. The population, average age of 45.23 (SD=17.56) years, 74% female, was sensitized at least to one allergen (53%) and non -sensitized in 47%. Twenty-five percent were monosensitized and 27% plurisensitized. The sensitization profile was respectively to Blomia tropicalis (72%), cat dander (46%), dog dander (34%), Alternaria alternata (13%) and egg yolk (11%). Conclusion. The present study indicates a plurisentisization feature in many asthmatics in our milieu ; mainly to dust mites and cat dander. Futher investigations involving a larger number of subjects and using broader test batteries are needed to improve diagnostic and therapeutic approaches in our context. Contexte. Environ 80% des asthmatiques sont atopiques. La sensibilisation aux allergènes communs présente certaines variabilités environnementales et géographiques. Objectif. Déterminer le profil de sensibilisation aux allergènes communs des asthmatiques adultes de la ville de Kinshasa. Méthodes. De juin 2017 à février 2018, 216 asthmatiques de 18 ans et plus, des 2 sexes, ont été consécutivement recrutés aux Cliniques Universitaires de Kinshasa et dans certaines paroisses et églises de réveil de la ville de Kinshasa. A l’aide d’un questionnaire validé, les variables sociodémographiques ont été précisées. Le prick-test a été réalisé avec cinq extraits commerciaux standardisés de phanères de chien et chat, l’acarien de poussière de maison (Blomia tropicalis, Bt), les moisissures (Alternaria alternata), et le jaune d’oeuf. Résultats. L’âge moyen de la population était de 45,23 (ET=17,56) ans, 74% de sexe féminin, 47 % non sensibilisés et 53% sensibilisés à au moins un allergène. Vingt-cinq pourcent étaient monosensibilisées et 27% plurisensibilisées. Le profil de sensibilisation était Blomia tropicalis (72%), phanères de chat (46%), phanères de chien (34%), Alternaria alternata (13%) et jaune d’oeuf (11%). Conclusion. Une plurisensibilisation aux allergènes communs chez les asthmatiques dans notre milieu est présente dont le profil dominé par les acariens et les phanères de chats. Des enquêtes futures incluant un plus grand nombre de sujets et recourant à des batteries de tests plus élargies s’imposent en vue d’une définition d’options diagnostiques et thérapeutiques dans notre contexte

Effect of In Vitro Digestion on the Antioxidant and Angiotensin-Converting Enzyme Inhibitory Potential of Buffalo Milk Processed Cheddar Cheese

The purpose of this study was to develop an in-vitro digestion protocol to evaluate the antioxidant potential of the peptides found in processed cheddar cheese using digestion enzymes. We first studied antioxidant and angiotensin-converting enzyme (ACE) inhibition and antioxidant activities of processed cheddar cheese with the addition of spices e.g., cumin, clove, and black pepper made from buffalo milk and ripened for 9 months. Then we conducted an in vitro digestion of processed cheddar cheese by gastric and duodenal enzymes. Freeze-dried water (WSE) and ethanol-soluble fractions (ESE) of processed cheddar cheese were also monitored for their ACE inhibition activity and antioxidant activities. In our preliminary experiments, different levels of spices (cumin, clove, and black pepper) were tested into a cheese matrix and only one level 0.2 g/100 g (0.2%) based on cheese weight was considered good after sensory evaluation. Findings of the present study revealed that ACE-inhibitory potential was the highest in processed cheese made from buffalo milk with the addition of 0.2% cumin, clove, and black pepper. A significant increase in ACE-inhibition (%) of processed cheddar cheese, as well as its WSE and ESE, was obtained. Lower IC50 values were found after duodenal phase digestion compared to oral phase digestion

Manifestations cliniques de l’infection à Coronavirus SARS-Cov-2 (COVID-19): Clinical characteristics of coronavirus infection disease (COVID-19)

The pandemic caused by the new coronavirus  (SARS-CoV-2) in Wuhan, China in December 2019 is a very contagious disease. The World Health Organization (WHO) has declared the ongoing epidemic to be a global public health emergency. Currently, research on this new coronavirus is in progress and several publications are available. The clinical manifestations linked to infection with the new Coronavirus-SARS-COV-2 virus seem to be polymorphic and multi-systemic, going beyond the typical respiratory nosological pattern described (fever, asthenia and respiratory symptoms cough and difficulty in breathing). These manifestations can be cardiovascular, dermatological, ORL, hepatic, renal, ophthalmological and neurological. This review describes the clinical manifestations as well as the pathogenesis known to date of the coronavirus disease 2019 (COVID-19); the diagnosis and treatment are not included in this mini review. La pandémie causée par le nouveau virus du coronavirus (SARS-CoV-2) à Wuhan, en Chine, en décembre 2019 est une maladie très contagieuse. L’Organisation mondiale de la Santé (OMS) a déclaré que l’épidémie en cours était une urgence mondiale de santé publique. Actuellement, les recherches sur ce nouveau coronavirus sont en cours et plusieurs publications sont disponibles. Les manifestations cliniques liées à l’infection au nouveau Corona-virus SARS-COV-2 semblent être très polymorphes et multi systémiques, dépassant largement le cadre nosologique typiquement respiratoire. Ces manifestations peuvent être cardio-vasculaires, dermatologiques, ORL, hépatiques, rénales, ophtalmologiques et même neurologiques. Cette revue décrit les manifestations cliniques ainsi que de la pathogénie connues à ce jour du coronavirus 2019 (COVID-19) ; le diagnostic et le traitement ne seront volontairement pas abordés

MULTIDRUG RESISTANT TUBERCULOSIS IN CHILDREN IN THE DEMOCRATIC REPUBLIC OF CONGO: FIRST EXPERIENCE WITH A SHORT TREATMENT COURSE IN A UNIVERSITY HOSPITAL

Background: A short treatment course for multidrug-resistant tuberculosis (MR-TB) is not yet well codified in children in the Democratic Republic of Congo (DRC). The objective of this study was to evaluate a short MR-TB treatment course in children. Methods: A prospective study was performed from April 2015 (corresponding to the inclusion) through April 2017 (and the later initiation time point was April 2016) in the University Clinics of Kinshasa. Enrolled children were aged 0 to 15 years. The treatment duration was in general for 9 months, with 4 months of intensive phase treatment with Kanamycin, Levofloxacin, Isoniazid, Pyrazinamide, Prothionamide, Clofazimine and Ethambutol, and 5 months of continuous phase treatment with Levofloxacin, Pyrazinamide, Clofazimine and Ethambutol. Frequencies were reported for significant results. Results: A total of 21 children had MDR-TB (11 males and 10 females). Fifteen (71.43%) were bacteriological confirmed cases (by Xpert/MTB), and 6 (28.57%) were clinically diagnosed (MDR-TB contact with suggestive radiologic lesions); 2 patients were coinfected with HIV, 15 cases had pulmonary TB, and 6 had extrapulmonary TB. The main radiologic findings included TB cavity (3 cases), pleural effusion (5 cases), alveolar syndrome (8 cases), adenopathy (7 cases), and interstitial infiltration, fibrosis and miliary (2 cases each). The Ziehl control was negative before 4 months of treatment in the majority of the cases. Overall, 11 patients were cured, 7 completed the treatment, 2 died and 1 was lost to follow up. Conclusions: MDR-TB remains a challenge in children. A more comfortable, short treatment course is feasible in children in the DRC. It is necessary to verify this observation with a larger cohort of MDR-TB patients in pediatrics. Keywords: Multidrug-resistant tuberculosis; children; short treatment course; Africa; Kinshasa; treatment outcomes

Tests diagnostiques de l’infection à Coronavirus (COVID-19) : des atouts et des limites: Diagnosis testing for Coronavirus infection disease (COVID 19): Assets and limits

The world is going through a serious health crisis due to the COVID 19 pandemic. Although little is known about COVID-19, we have observed an increased interhuman transmission of etiological agent SARS-Cov-2 and we assume that each new cases of COVID-19 get at least two or three news persons infected. Therefore, the test for detection of the infection should be much implemented as an efficient strategy to fight against the COVID 19 pandemic. The COVID-19 diagnostic tests are an essential tool for assessing the pandemic. This review paper will discuss the advantages and limitations of the diagnosis tests for COVID 19. There are 2 categories of tests: those that directly detect the virus or its component, and those that search for the antibodies generated by the virus infection. The real time Reverse transcriptase Polymerase chain reaction (test rt-RT-PCR) remains the gold standard for the diagnosis of COVID-19. Its sensitivity on the nasopharynx swab seems high, though false negative cases can occur, with an average of 30% of cases. Serological test detect specific antibodies against SARS-COV-2. They help identify individuals that have been infected by the virus, those healed and that have acquired immunity against the virus. They are diagnosis orientation tests of COVID-19. Until now, none of these tests are 100% reliable, but they are used by a qualified collaborating medical staff. They can help identify the majority of the infected and immunized individuals. Le monde entier fait face à une crise sanitaire sans précédent due à la pandémie de maladie à virus SARS-COV-2 alias COVID-19. Malgré les connaissances très incomplètes sur la COVID-19, on a constaté une contagiosité interhumaine élevée au début de la pandémie actuelle, et on estime que chaque nouveau cas de COVID-19 infecte en moyenne deux à trois personnes. En conséquence, la stratégie de lutte contre la pandémie à COVID-19 qui ébranle nos sociétés passe nécessairement par une intensification des tests de détection de l’infection. Ces tests diagnostiques de la COVID-19 sont un outil essentiel pour suivre la propagation de la pandémie. Ainsi, l’objectif de la présente revue de la littérature est d’aborder le diagnostic de l’infection à Coronavirus (COVID-19) en s’attardant sur les tests de diagnostic, leurs atouts et leurs limites. Il y a deux catégories de test : ceux qui recherchent la présence directe du virus ou de ses fragments, et ceux qui recherchent les anticorps résultant de l’infection par le virus du COVID-19. Le test real time –Reverse Transcriptase –Polymerase chain reaction (rt-RT-PCR) reste le gold standard pour le diagnostic de la COVID-19. Sa sensibilité sur les écouvillons nasopharyngés semble élevée, mais des faux négatifs peuvent se produire, avec une fréquence incertaine (environ 30% des cas). Les tests sérologiques détectent les anticorps spécifiques du SARS-CoV-2. Ils permettent l’identification des individus qui ont été infectés par le virus, se sont rétablis, et ont développé, en théorie, une réponse immunitaire efficace contre le virus. Ils constituent des tests d’orientation diagnostique de la COVID-19. A ce jour, aucun de ces tests n’est fiable à 100 %, mais, utilisés par un personnel médical qualifié et en combinaison, ils permettent l’identification de la majorité des individus infectés et immunisés

Serum Vitamin D Levels in a Population of Adult Asthmatics in Kinshasa, Democratic Republic of Congo

Background: Vitamin D deficiency is common in general population and is thought to be involved in the natural history of several chronic lung diseases such as asthma. However, the magnitude of the association has not yet been reported in asthmatic adults in Sub-Saharan Africa.  The aim of this study was to determine serum vitamin D levels in adult patients with asthma living in Kinshasa. Methods: A sample of 216 subjects reporting asthma were recruited from the University Clinics of Kinshasa and some parishes in Kinshasa. Socio-demographic data were recorded, nutritional status assessed via body mass index (BMI) calculation, FEV1 values obtained, and serum vitamin D levels measured. Serum vitamin D levels were analyzed according to the time spent outdoors in the sun and their correlation with BMI and FEV1. Results: Participants were on average 45.23 years old (SD 17.56) and predominately female (74%). Serum vitamin D levels ranged from 5 to 42 ng/ml, with an average of 20.8 ng/ml (SD 6.1). Vitamin D levels were normal (≥30 ng/ml) in ten subjects (4.8%; 95% CI: 1.9-7.7) and abnormal (<30 ng/ml) in 197 subjects (95.2%; 95% CI: 92.0-98.0); of this latter group, 89% (95% CI: 84.6-93.2) were vitamin D insufficient (10-29 ng/ml) and 6% (95% CI: 3.0-9.6) vitamin D deficient (<10 ng/ml).Mean serum vitamin D levels did not differ based on the time spent outdoors in the sun (p = 0.714), and there was no correlation between serum vitamin D and FEV1 (r = 0.018) or BMI (r = 0.033). Conclusions: Vitamin D insufficiency is common in adult asthmatics in Kinshasa but does not appear to be correlated with FEV1 or BMI. Additional population-based surveys are needed to fully assess associations between asthma and vitamin D concentrations for targeted interventions

Assessment of treatment outcomes of multidrug-resistant tuberculosis patients in D R Congo: A study based on drug regimens used between 2007 to 2017: Évaluation des issues thérapeutiques des patients atteints de la tuberculose à bacilles multi résistants : étude basée sur les régimes de médicaments utilisés en République Démocratique du Congo de 2007 à 2017

Context. Little is known about therapeutic successes in MDR-TB patients under regimens containing second-line molecules. The present study aimed to assess therapeutic outcomes in patients under therapeutic regimens applied in DR Congo. Methods. This historical cohort study has included confirmed MDR-TB patients who received treatment between 2007 and 2017 in 218 TB centers in DR Congo. Treatment outcome and survival at 36 months were analyzed using Zscore and chi square test. Kaplan-Meier method was performed to describe survival and Log Rank test helped in comparing curve based on the therapeutical regimen. Factors associated with therapeutic success and mortality predictors were assessed using multivariate logistic regression and Cox regression analysis, respectively. Results. The therapeutic success in the study group (n=1,724) was 72% (range 68-74%) for all regimen combined. The average death rate was 12.8% although the group of patients receiving Cyclosérine and Ofloxacine was the most affected (16%). The death rate was significantly higher in patients living in urban areas (15.2% versus 14.9%, p = 0.013) and also among MDR-TB/HIV co-infected patients (28.4% vs 15.7%, p<0.001) patients. The median survival of the study group was 722.7 days compared to 601.1 days for MDR-TB/HIV co-infected patients, and 736.7 days for HIV negative patients (p<0.001). Conclusion. Therapeutic successes are significant for the short regimen. However, the death rate remains high when Cycloserine and Ofloxacin are included in the regimen. The predictors of mortality are HIV infection and living in urban areas. Contexte. L’issue thérapeutique de la tuberculose multi résistante (TB-MR) sous les molécules de deuxième intention n’est pas très bien connue. La présente étude a évalué les régimes thérapeutiques appliqués, en termes de succès thérapeutique et de survie. Méthodes. L’étude de cohorte historique a inclu les patients TB-MR confirmés et traités entre 2007 et 2017 dans 218 centres de tuberculose en RD Congo. L’issue thérapeutique et la survie à 36 mois ont été analysées. Le score Z ou le test de chi carré ont comparé des issues. La méthode de Kaplan-Meier a décrit les courbes de survie et le test de Log Rank a comparé la survie en fonction du regime therapeutique. Les facteurs associés au succès thérapeutique et les prédicteurs de mortalité ont été analysés respectivement, par l’analyse multivariée de régression logistique et de Cox. Résultats. Dans le groupe étudié (n=1724), le succès thérapeutique a été de 72% (68-74%) pour l’ensemble des régimes. Le taux était plus élevé pour le régime court (74%) et plus faible pour le régime contenant la Cyclosérine et l’Ofloxacine (68%). La moyenne de décès était de 12,8% ; mais plus élevée dans le groupe sous regime contenant la Cyclosérine et l’Ofloxacine (16%). Le taux de décès était significativement plus élevé en milieu urbain (15,2% versus 14,9 %, p = 0,013) et également chez les sujets co-infectés par la MDR-TB  et le VIH (28.4% vs 15.7%, p <0,001). La survie médiane dans le groupe était de 722,7 jours contre 601,1 jours chez les co-infectés MDR-TB/VIH, et de 736,7 jours) chez les patients VIH négatifs (p<0,001). Conclusion. Les succès thérapeutiques sont acceptables en particulier, pour le régime court ; toutefois, le taux de décès demeure encore très élevé dans le groupe sous Cyclosérine et Ofloxacine. Les prédicteurs de mortalité sont l’infection à VIH et la vie citadine. &nbsp

Obesity and diabetes mellitus association in rural community of Katana, South Kivu, in Eastern Democratic Republic of Congo : Bukavu Observ Cohort study results

Background: Factual data exploring the relationship between obesity and diabetes mellitus prevalence from rural areas of sub-Saharan Africa remain scattered and are unreliable. To address this scarceness, this work reports population study data describing the relationship between the obesity and the diabetes mellitus in the general population of the rural area of Katana (South Kivu in the Democratic Republic of the Congo). Methods: A cohort of three thousand, nine hundred, and sixty-two (3962) adults (>15 years old) were followed between 2012 and 2015 (or 4105 person-years during the observation period), and data were collected using the locally adjusted World Health Organization's (WHO) STEPwise approach to Surveillance (STEPS) methodology. The hazard ratio for progression of obesity was calculated. The association between diabetes mellitus and obesity was analyzed with logistic regression. Results: The diabetes mellitus prevalence was 2.8 % versus 3.5 % for obese participants and 7.2 % for those with metabolic syndrome, respectively. Within the diabetes group, 26.9 % had above-normal waist circumference and only 9.8 % were obese. During the median follow-up period of 2 years, the incidence of obesity was 535/100,000 person-years. During the follow-up, the prevalence of abdominal obesity significantly increased by 23 % (p < 0.0001), whereas the increased prevalence of general obesity (7.8 %) was not significant (p = 0.53). Finally, diabetes mellitus was independently associated with age, waist circumference, and blood pressure but not body mass index. Conclusion: This study confirms an association between diabetes mellitus and abdominal obesity but not with general obesity. On the other hand, the rapid increase in abdominal obesity prevalence in this rural area population within the follow-up period calls for the urgent promoting of preventive lifestyle measures