Aspects cliniques et pronostiques des accidents vasculaires cérébraux en réanimation au Cameroun / Clinical and prognostic aspects of stroke in a Cameroonian intensive care unit

Introduction. L'accident vasculaire cérébral (AVC) est une pathologie fréquente. Le but de l'étude était de décrire les aspects pronostiques des AVC en réanimation. Patients et Méthodes. Il s'agissait d'une étude longitudinale descriptive et analytique, qui s'est déroulée de janvier à avril 2019. Nous avons recruté dans les services de réanimation de trois hôpitaux universitaires de Yaoundé. Etait inclus, tout patient hospitalisé en réanimation pour prise en charge d'un AVC, ayant réalisé un scanner cérébral. Le consentement était obtenu auprès du patient ou d'un parent. Les variables étaient les données sociodémographiques, les données cliniques et pronostiques.Les données étaient analysées à partir du logiciel Epi info 3.5.4 et Microsoft Office Excel 2013. Les proportions étaient comparées par le test de Chi carré ou le test exact de Fisher. Les médianes étaient comparées par le test de MannWhitney. La survie était représentée par une courbe de Kaplan Meier. Résultats. Au total, 34 patients étaient inclus. L'âge moyen était de 59,9±9,7 ans. Le sex-ratio était de 0,7. Le délai moyen d'admission était de 4,5±4,84 jours. L'hypertension artérielle était le facteur de risque dominant (42,5%). Une altération de la conscience était fréquente (73,5%). L'hémiplégie constituait le principal signe neurologique focal. L'AVC hémorragique était retrouvé chez 58,8% des patients. Deux patients étaient intubés (5,88%). Dix-huit décès étaient enregistrés (52,9%). La durée moyenne du séjour était de 21,8±19,4 jours. Les facteurs pronostiques étaient le score de Glasgow <8 (P=0,01), le score de NIHSS≥15 (P=0,001), l'hyperthermie (P=0,04), la présence de trouble de la déglutition à l'entrée (P=0,01) et l'effet de masse au scanner cérébral (P=0,01). Conclusion. Les AVC restent une affection fréquente dans notre pays. La mortalité est élevée.Elle est liée à la gravité clinique et la survenue des complications

Background. Stroke is a frequent pathology. The aim of the study was to describe the clinical, and prognostic aspects of stroke in the intensive care unit (ICU). Patients and Methods. This was a longitudinal descriptive and analytical study, which took place from January to April 2019. We recruited from the intensive care units of three university hospitals in Yaoundé. Any patient hospitalised in the ICU for stroke management who had undergone a brain scan was included. Consent was obtained from the patient or a relative. The variables were socio-demographic data, clinical data, therapeutic data and outcome. Data were analysed using Epi info 3.5.4 and Microsoft Office Excel 2013. Proportions were compared using the Chi-square test or Fisher's exact test. Medians were compared by the Mann-Whitney test. Survival was represented by a Kaplan Meier curve. Results. A total of 34 patients were included. The mean age was 59.9±9.7 years. The sex ratio was 0.7. The mean time to admission was 4.5 days ±4.84. Hypertension was the dominant risk factor (42.5%). Altered consciousness was common (73.5%). Hemiplegia was the main focal neurological sign. Hemorrhagic stroke was found in 58.8% of the patients. All patients received general measures. Two patients were intubated (5.88%). Eighteen deaths were recorded (52.9%). The average length of stay was 21.8±19.4 days. Prognostic factors were Glasgow score <8 (P=0.01), NIHSS score≥15 (P=0.001), hyperthermia (P=0.04), presence of swallowing disorder at admission (P=0.01) and mass effect on brain scan (P=0.01). Conclusion. Stroke remains a frequent condition in our country. Mortality is high. It is related to the clinical severity and the occurrence of complications.

Alarming rates of virological failure and HIV-1 drug resistance amongst adolescents living with perinatal HIV in both urban and rural settings: evidence from the EDCTP READY-study in Cameroon.

OBJECTIVES: Adolescents living with perinatal HIV infection (ALPHI) experience persistently high mortality rates, particularly in resource-limited settings. It is therefore clinically important for us to understand the therapeutic response, acquired HIV drug resistance (HIVDR) and associated factors among ALPHI, according to geographical location. METHODS: A study was conducted among consenting ALPHI in two urban and two rural health facilities in the Centre Region of Cameroon. World Health Organization (WHO) clinical staging, self-reported adherence, HIVDR early warning indicators (EWIs), immunological status (CD4 count) and plasma viral load (VL) were assessed. For those experiencing virological failure (VF, VL ≥ 1000 copies/mL), HIVDR testing was performed and interpreted using the Stanford HIV Drug Resistance Database v.8.9-1. RESULTS: Of the 270 participants, most were on nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens (61.7% urban vs. 82.2% rural), and about one-third were poorly adherent (30.1% vs. 35.1%). Clinical failure rates (WHO-stage III/IV) in both settings were < 15%. In urban settings, the immunological failure (IF) rate (CD4  < 250 cells/µL) was 15.8%, statistically associated with late adolescence, female gender and poor adherence. The VF rate was 34.2%, statistically associated with poor adherence and NNRTI-based antiretroviral therapy. In the rural context, the IF rate was 26.9% and the VF rate was 52.7%, both statistically associated with advanced clinical stages. HIVDR rate was over 90% in both settings. EWIs were delayed drug pick-up, drug stock-outs and suboptimal viral suppression. CONCLUSIONS: Poor adherence, late adolescent age, female gender and advanced clinical staging worsen IF. The VF rate is high and consistent with the presence of HIVDR in both settings, driven by poor adherence, NNRTI-based regimen and advanced clinical staging.

Energy Spectrum of Two-Dimensional Excitons in a Nonuniform Dielectric Medium.

We demonstrate that, in monolayers (MLs) of semiconducting transition metal dichalcogenides, the s-type Rydberg series of excitonic states follows a simple energy ladder: ε_{n}=-Ry^{*}/(n+δ)^{2}, n=1,2,…, in which Ry^{*} is very close to the Rydberg energy scaled by the dielectric constant of the medium surrounding the ML and by the reduced effective electron-hole mass, whereas the ML polarizability is accounted for only by δ. This is justified by the analysis of experimental data on excitonic resonances, as extracted from magneto-optical measurements of a high-quality WSe_{2} ML encapsulated in hexagonal boron nitride (hBN), and well reproduced with an analytically solvable Schrödinger equation when approximating the electron-hole potential in the form of a modified Kratzer potential. Applying our convention to other MoSe_{2}, WS_{2}, MoS_{2} MLs encapsulated in hBN, we estimate an apparent magnitude of δ for each of the studied structures. Intriguingly, δ is found to be close to zero for WSe_{2} as well as for MoS_{2} monolayers, what implies that the energy ladder of excitonic states in these two-dimensional structures resembles that of Rydberg states of a three-dimensional hydrogen atom.

Tetrameres (Tetrameres) megaphasmidiata n. sp. (Nematoda: Tetrameridae), a parasite of the two-banded plover, Charadrius falklandicus, and white-rumped sandpiper, Calidris fuscicollis, from Patagonia, Argentina.

Tetrameres (Tetrameres) megaphasmidiata n. sp. is described from the proventriculus of the two-banded plover, Charadrius falklandicus, and the white-rumped sandpiper, Calidris fuscicollis, from Patagonia, Argentina. The new species shares with T. (T.) nouveli, T. (T.) paradisea, T. (T.) prozeskyi, T. paraaraliensis, T. (T.) cladorhynchi, and T. lobybicis the absence of the right spicule and the presence of 4 rows of somatic spines. Tetrameres (T.) megaphasmidiata n. sp. differs from the first 4 species mainly by its longer left spicule. The new species can be distinguished from T. (T.) cladorhynchi by the extension of the lateral alae, the number and arrangement of the caudal papillae, and the absence of polar filaments in the eggs. Tetrameres lobybicis differs from the new species by having shorter rows of dorsal spines and a different number and arrangement of the caudal papillae. This report is the first record of a species of Tetrameres in C. falklandicus and C. fuscicollis.

Mycobacterium tuberculosis H37Rv parietal and cellular lipoarabinomannans. Characterization of the acyl- and glyco-forms.

Mannosylated lipoarabinomannans are multifaceted molecules. They have been shown to exert an immunosuppressive role in the immunopathogenesis of tuberculosis. They are also described as antigens of host double negative alphabeta T-cells. Delimitation of ManLAMs epitopes require knowledge of the precise structure of these molecules. The two major functional domains (the cap motifs and the phosphatidylinositol anchor) of the parietal and cellular ManLAMs of Mycobacterium tuberculosis H37Rv were investigated here. Using capillary electrophoresis, we established that parietal and cellular ManLAMs share the same capping motifs, mono-, di-, and trimannosyl units with the same relative abundance. By (31)P NMR analysis of the native LAMs in Me(2)SO-d(6), the major acyl-form of both parietal and cellular H37Rv ManLAM anchors, typified by the P3 phosphorus resonance, comprised a diacylglycerol unit. Three other acyl-forms were characterized in the cellular ManLAMs. Comparative analysis of the cellular Mycobacterium bovis BCG and M. tuberculosis ManLAM acyl-forms revealed the presence of the same populations, but with different relative abundance. The biological importance of the H37Rv ManLAM acyl-form characterization is discussed, particularly concerning the molecular mechanisms of binding of ManLAMs to the CD1 proteins involved in the presentation of ManLAMs to T-cell receptors.

Picroliv, the iridoid glycoside fraction of Picrorhiza kurroa, selectively augments human T cell response to mycobacterial protein antigens.

Mycobacterial and other intracellular parasitic diseases are characterised by a deficiency in antigen specific host T cell responses. We have studied the effect of Picroliv, a standardised fraction of root and rhizome of Picrorhiza kurroa, on proliferative T cell response to the mycobacterial 'Purified Protein Derivative (PPD)' antigen in subjects infected with or exposed to mycobacteria (tuberculoid leprosy patients and endemic normals). Coculture of their peripheral blood mononuclear cells with the optimal concentration of Picroliv (0.5 microgram/ml) significantly enhanced the proliferative response to 1/10 optimal PPD dose, as determined by [3H] thymidine incorporation, in the group of 'low' responders. The response to PPD of cells from 'high responders' and to PHA (phytohaëmagglutinin, a non-specific T cell mitogen) remained unaffected by Picroliv which did also not induce cell proliferation on its own. The selective, antigen specific augmentation of human T cell response suggests that Picroliv could be useful as an adjunct to chemotherapy or as a short term prophylactic agent.