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Sous l’effet de divers facteurs, le cheptel zébu Mbororo de la RCA s’est considérablement accru durant ces dernières années (2 200 000 têtes) du fait des potentialités pastorales offertes. En vue d’une meilleure gestion de cet espace, des zones d’activité agropastorale ont été créées (ZAGROP). En contrepartie du disponible fourrager, cet élevage en zone humide doit affronter des contraintes pathologiques accrues, dominées notamment par les trypanosomoses. Pour éviter que l’usage massif actuel des trypanocides par les éleveurs n’aboutisse à une impasse, l’Agence Nationale de Développement de 1’Elevage (ANDE) a demandé d’identifier des méthodes de lutte contre les glossines. Dans l’une de ces ZAGROP (60 000 ha), la première étape a consisté à établir une carte précise de la distribution des espèces vectrices grâce à un piégeage systématique (piège biconique). Glossina fuscipes fuscipes (10 805 glossines capturées) occupe la totalité du réseau hydrographique avec des densités faibles à moyennes (3 glossines par piège et par jour). Glossina fusca eongolensis est rare (7 individus capturées) et Glossina morsitans submorsitans, autrefois présente, semble avoir disparu. Les éléments sur l’abondance, la diversité et la distribution des espèces sont discutés. Ils servent de base au choix d’une méthode de lutte par piégeage actuellement mise en oeuvre dans ce milieu pastoral.

La recherche d'un nouveau piège destiné à la prise en charge par les éleveurs centrafricains (Peuls) de la lutte contre Glossina fuscipes fuscipes a été réalisée en expérimentant séparément le système de capture, le corps du piège et les matériaux. Le résultat est la mise au point du piège bipyramidal en tulle et plastique bleu et noir. Il n'est pas imprégné d'insecticide mais utilise un système de capture à sec, tuant et conservant les glossines, dont le rendement est de deux à quatre fois celui de la cage Roubaud classiquement utilisée. Ce piège est plus efficace que les pièges biconiques, pyramidaux ou monoconiques essayés en RCA. Le pouvoir discriminant du protocole en carré latin et l'usage du piège avec ou sans insecticide sont discutés.

Le "glissement" historique des éleveurs Mbororo d'ouest en est s'accélère sous divers facteurs, dont la sécheresse, et les pousse à s'installer plus loin et plus durablement dans les savanes humides infestées de glossines. Pour limiter l'usage important des trypanocides et trypanopréventifs dans une "zone d'action agropastorale" en création en RCA, un essai de lutte contre Glossina fuscipes fuscipes est mis en place par piépeage ponctuel à l'aide de deux pièges biconiques classiques (non imprégnés d'insecticide), installés à chaque abreuvoir (deux abreuvoirs par campement) dans 32 campements d'éleveurs sédentaires en saison des pluies et plus ou moins transhumants en saison sèche. L'éleveur collecte lui-même les glossines prises et surveille le bon état des pièges. Les réductions de densité apparente sont très fortes après un mois et en général supérieures à 90 p. 100 après deux mois. Elles sont plus rapides et homogènes en saison sèche qu'en saison des pluies. Dans cet essai, les éleveurs ont bien géré leurs pièges. Ils sont motivés et demandeurs de cette technique simple de lutte. Le problème de son application en milieu semi-sédentaire est posé. L'information et la formation données aux éleveurs devra s'intensifier par divers moyens (fiche technique, montage audiovisuel, stages).

We investigate the combination of nitrogen doping and vacancies in highly ordered pyrolytic graphite (HOPG), to engineer defect sites with adjustable electronic properties. We combine scanning tunneling microscopy and spectroscopy and density functional theory calculations to reveal the synergistic effects of nitrogen and vacancies in HOPG. Our findings reveal a remarkable shift of the vacancy-induced resonance peak from an unoccupied state in pristine HOPG to an occupied state in nitrogen-doped HOPG. This shift directly correlates with the shift of the charge neutrality point resulting from the n-doping induced by substitutional nitrogen. These results open new avenues for defect engineering in graphite or graphene and achieving novel functionalities for chemical activity or electronic properties., (© 2024 Wiley-VCH GmbH.)

Thyroid abscess is a very rare disease due to its anatomical position and the physiology of the gland. It most often occurs in the immunosuppressed population. The diagnosis is easy and is based on ultrasound. However it is often unrecognised. Bacteriological examination allows to identify the germ responsible for this condition. We report the case of a Mauritanian patient living in the said country presenting with painful cervical swelling associated with fever. The diagnosis was based on ultrasound and confirmed by fluid examination. Bacteriological assessment didn't identify the cause of this condition. Patient's outcome was marked by regression of symptoms under antibiotic therapy, with normalization of the gland structure after two months., Competing Interests: Les auteurs ne déclarent aucun conflit d'intérêts., (© Diallo Ibrahima Mané et al.)

Introduction: This study aims to determine the clinical and evolutionary profile of skin and soft tissue lesions in diabetics followed up at the dressing room., Methods: We conducted an observational descriptive and analytical study in the dressing room of the Marc Sankalé Diabetes Center, Dakar from 1 January to 31 December 2017. Our study focused on diabetics who were examined in the dressing room., Results: A total of 37.173 procedures were recorded at the Marc Sankalé Diabetes Center; 16.418 patients were treated in the dressing room, representing a prevalence of 14.16%. The average age of patients was 56,6 ±12 years, the sex ratio (M/F) was 0,88. Type 2 diabetes predominated (78,97%) and the average disease duration was 8.06 ± 7.9 years. The mean capillary blood glucose concentration was 2.4±1 g/l. Diabetic neuropathy was found in 72.33% of patients. Limb lesions were found in 93,98% of patients(1185 cases). The most common lesions included: ulcer (46,76%), abscess (13.46%), phlegmon (13.20%), gangrene (8.41%), erysipelas (3.78%), perforating ulcer (3.53%), intertrigo (3.95%). The lesions were be divided into infectious lesions (61,41), non-infectious lesions(33,50%), pure vascular lesions (1.57%) and mixed lesions (3.70%). Out of 1189 patients 7.57% had had osteitis. The germs found were Gram-positive bacteria (12.70%), Gram-negative bacteria (23.80%). Amputation was performed according to the topographical features of the lesion (p=0.00), the type of lesion (p=0.000), the seniority of diabetes (p=0.02), the type of diabetes (p=0.008), the presence of osteitis (p=0.006). Minor amputation was performed in 43,33% of cases, major amputation in 37.43% of cases; 70 deaths were recorded (5.89%)., Conclusion: Skin and soft tissue lesions were dominated by diabetic foot. Mortality is not negligible and the risk of amputation was statistically related to the topographical features of the lesion, the type of lesion, the seniority and the type of diabetes and the presence of osteitis., Competing Interests: Les auteurs ne déclarent aucun conflit d'intérêts.

Four types of human T cell lymphotropic viruses (HTLV) have been described (HTLV-1 to HTLV-4) with three of them having closely related simian virus analogues named STLV-1, -2, and -3. To assess the risk of cross-species transmissions of STLVs from nonhuman primates to humans in the Democratic Republic of Congo, a total of 330 samples, derived from primate bushmeat, were collected at remote forest sites where people rely on bushmeat for subsistence. STLV prevalences and genetic diversity were estimated by PCR and sequence analysis of tax-rex and LTR fragments. Overall, 7.9% of nonhuman primate bushmeat is infected with STLVs. We documented new STLV-1 and STLV-3 variants in six out of the seven species tested and showed for the first time STLV infection in C. mona wolfi, C. ascanius whitesidei, L. aterrimus aterrimus, C. angolensis, and P. tholloni. Our results provide increasing evidence that the diversity and geographic distribution of PTLVs are much greater than previously thought.

Like most emerging infectious disease viruses, HIV is also of zoonotic origin. To assess the risk for cross-species transmission of simian immunodeficiency viruses (SIVs) from nonhuman primates to humans in the Democratic Republic of Congo, we collected 330 samples derived from nonhuman primate bushmeat at 3 remote forest sites. SIV prevalences were estimated by using a novel high-throughput assay that included 34 HIV and SIV antigens in a single well. Overall, 19% of nonhuman primate bushmeat was infected with SIVs, and new SIV lineages were identified. Highest SIV prevalences were seen in red-tailed guenons (25%) and Tshuapa red colobus monkeys (24%), representing the most common hunted primate species, thus increasing the likelihood for cross-species transmission. Additional studies are needed to determine whether other SIVs crossed the species barrier. With the newly developed assay, large-scale screening against many antigens is now easier and faster.

Four herds of Mbororo Zebu cattle (approximately 40 head each) in traditional situation of the Fulani breeders were treated over a 12 month period. Flumethrin Pour on was first used every three weeks during the rainy season and then deltamethrin Spot on was used every six weeks during the dry season. Pour on treatments might affect the age structure and feeding patterns of the neighbouring populations of G fuscipes. However, the treatments had no impact on the apparent density of flies. They changed neither the prevalence of trypanosome infection rates in cattle nor the hematocrit levels. This trial shows that, under these experimental conditions, insecticide treatments were not effective for the control trypanosomosis in cattle. Further trials should be carried out to assess the usefulness of this method when it is integrated with the trapping of tsetse flies.

From 1987 to 1993, a survey on the feeding behavior of Glossina fuscipes fuscipes was conducted in the Central African Republic. A total of 556 blood-meal samples was analyzed by ELISA. According to the results, the number of blood meals from cattle was rather low (12% on average). During the rainy season, this number increased significantly and varied according to the sampling area. Along the riverine forests, this amounted to 5%, while blood meals from wild ruminants amounted to 87%. In the neighborhood of watering-places, the number of cattle blood meals reached 9-22%. Reptiles were found to be important hosts (17-35%). In all cases, man presented a non-negligible host (4-14%), similar to suidae (2-19%). The authors discuss the relevance of these results to risk of trypanosomes transmission.