Train-the-trainers intervention for national capacity building in infection prevention and control for COVID-19 in Nigeria.

Background: The first case of COVID-19 in Nigeria was reported on February 27, 2020, and over time, spread across the country leading to many healthcare worker infections. The risk of transmission of COVID-19 within healthcare facilities makes it necessary to establish infection prevention and control measures. The World Health Organisation supported the Nigeria Centre for Disease Control to conduct a train-the-trainers workshop on infection prevention and control for key healthcare workers across Nigeria. Aim/Objectives: This study aims to describe the process and results of train-the-trainers as an intervention for national capacity building in infection prevention and control for COVID-19 among healthcare workers in Nigeria. Methods: Eight-hour sessions were held over three days with face-to-face instruction and practical hands-on experience in April 2020. A total of 61 healthcare workers participated across the six geographic zones of Nigeria: North Central, North East, North West, South West, South East, and South South. The training included slide presentations, case-based scenarios, and practical hands-on sessions with plenary discussions. Pre- and post-test assessments were used to evaluate knowledge of COVID-19, triage, and infection prevention and control among healthcare workers. Finding/Results: 69 % (42) of the participants were male 31 % (19) were female, and the majority (67 %) were medical doctors. Others attending were nurses or health administrators. Of the 70 % (26) of the states with existing infection prevention and control structures within the COVID emergency response, only 40 % were functional. The average percentage of pre-test and post-test scores were 60.8 ± 13.4 and 67.8 ± 9 0.3 respectively, showing a statistically significant difference (p > 0.001) in trainee knowledge. Additionally, 70 % of participants evaluated the training workshop as "satisfactory" or higher in training format, relevance for daily clinical work, active participation, learning new concepts, and logistics. Conclusion: Nationwide infection prevention and control training is feasible during a national health crisis. Infection prevention and control is cardinal in the containment of epidemic-prone diseases like COVID-19 and is invaluable in the prevention of healthcare-associated infections in healthcare settings.

The vascular endothelium masks the persistent inhibition of rat thoracic arterial tone induced by S-nitrosoglutathione.

AIM: In endothelium-denuded arteries, the nitric oxide (NO) donor S-nitrosoglutathione (GSNO) induced a persistent hypo-reactivity to vasoconstrictors, and low-molecular weight thiols such as N-acetyl cysteine (NAC) produced a relaxant effect. These effects were attributed to the formation of vascular NO stores. In arteries with a functional endothelium, such long-lasting effects on arterial tone have not been well characterised. In this study, we proposed to examine the possibility of storing exogenous NO when the vascular endothelium is still able to produce its own NO. METHODS: For this purpose, changes in isometric tension of isolated arteries were assessed in organ chambers, and nitrosothiol formation was characterised by confocal microscopy. RESULTS: In rat aortic rings with endothelium pre-exposed to GSNO, the contractile response to norepinephrine (NE) was not attenuated in comparison with control rings, but NAC induced a relaxant effect. However, an attenuation of the response to NE was observed in GSNO-exposed, intact aortic rings after inhibition of NO synthase by N(ω)-nitro-L-arginine methylester (L-AME) or in GSNO-denuded rings. The relaxing effects of NAC were due to the mobilisation of NO from nitrosothiols after nitrosylation of protein SH residues. Moreover, the hypo-reactivity to NE and the relaxant effect of NAC were abolished by 1H-[1,2,4] oxadiazolo(4,3-a)quinoxalin-1-one (ODQ), an inhibitor of soluble guanylyl cyclase, and partially by the K+-sensitive channel inhibitor tetra-ethyl-ammonium (TEA). CONCLUSION: These data show that endothelium-derived NO masked the persistent effect of GSNO in rat thoracic aorta. However, the ability of GSNO to form releasable NO stores without altering the vascular tone can be particularly useful in preventing endothelial dysfunction in which NO formation decreases.

[Enhancing the anthelminthic activity roots of Annona sengalensis]. / Mise en evidence de l'activite antihelminthique des racines d'Annona senegalensis.

INTRODUCTION: Annona senegalensis is a plant largely used in traditional medicine in Africa. The roots showed an antiparsitic activity. The purpose of this work is to determine through bioassay on Rhabditis pseudoelongata the activity of the roots of Annona senegalensis and characterise if any substances responsible for this activity. MATERIAL AND METHODS: The vegetable material consists of roots of Annona senegalensis collected in Casamance at 1999. The tests of activity are carried out on Rhabditis pseudoelongata, stock L. Lamy, Institut Pasteur, Paris. Powder of roots (1070 g) was extracted with methanol. From this rough extract, we carried out two extractions with the dichloromethane of which one after passages in alkaline and acid medium. Various extracts were subjected to a chromatography on column of silica gel or from alumina gel; some compounds were isolated by high performance liquid chromatography . The identification of compounds was deed using spectrometric techniques (mass, Ultraviolet, Infrared) and nuclear magnetic resonance. The tests of activity related to three extracts and seven molecules isolated from the roots. The percentage of dead worm is determined after two hours of contact with demineralised water containing the sample to be tested. RESULTS: The neutral extract chloromethylenic showed an important activity on Rhabditis pseudoelongata. Five acetogenines were insulated starting from this extract chloromethylenic (gigantetronenine, squamocine, glaucanisine, glaucanetine, goniothalamicine) and two alkaloids starting from the alkaline extract chloromethylenic (liriodenine and norolivéroline). The tests on Rhabditis pseudoelongata of these compounds showed an activity of the squamocine with a IC50 of 0.1 microg/ml and IC90 0.3 microg/ ml more powerful than that of the levamisole, reference substance (IC50 of 0.8 microg/ml and IC90 13 microg/ml). CONCLUSION: The study of the biological activity of the roots of Annona senegalensis made it possible to determine the anthelminthic activity of the extract chloromethylenic from where the squamocine was isolated. The presence of this molecule could explain the anthelminthic activity of this plant.

[Cytotoxic activity of two cyclic peptides from the latex of Jatropha integerrima Euphorbiaceae]. / Etude de l'activite cytotoxique de deux cyclopeptides isoles du latex de jatropha integerrima euphorbiaceae.

Activity-guided fractionation of the ethyl acetate extract of the latex of Jatropha integerrima Euphorbiaceae combinated with cytotoxic assay against the KB human nasopharyngeal carcinoma cells, resulted to the isolation by chromatographic methods including HPLC of two new cyclopeptides: integerrimacyclopeptide4 and integerrima cyclopeptide B. The amino acid composition was established after hydrolysis and derivatization. All chiral amino acids were L configuration and were hydrophobic. Their sequences were determined by MS fragmentations (ESI-q-TOF, MS/MS) and confirmed by 2D NMR homo- and heteronuclear studies. Integerrimacyclopeptide A was a cyclooctapeptide with m/z 766 corresponding to the molecular formula C37H66N8O9. Analysis of mass spectra gave b(n) and a(n) acylium ion series which the sequence could be deduced: cyclo(Leu-Gly-Ser-Ile-Ile-Leu-Gly-lle). This structure was confirmed by interpretation of HMBC and ROESY spectra. Likewise, integerrimacyclopeptide B was a cycloheptapeptide with m/z 651 and C31H53N7O8 as molecular formula containing one proline residue: cyclo(Pro-Gly-Thr-Ile-Gly-Ile-Leu). These two cyclic peptides exhibited significant cytotoxic activityin vitro against KB tumorales cells with respective IC50 values of 0.46 +/- 0.04 and 0.66 +/-0.08 microg/ml.

[Mechanisms of action of acetonic and hexanic extracts of leaves of Vernonia colorata (Willd.) Drake (Composeae) on blod glucose regulation]. / Mecanismes d'action des extraits acetonique et hexanique de feuilles de Vernonia colorata dans la regulation de la glycemie.

INTRODUCTION: This study aimed to investigate the mechanism of action of acetonic and hexanic extracts of the leaves of Vernonia colorata on blood glucose regulation. MATERIALS AND METHODS: Experiments were performed in normoglycaemic, type 1 and 2 diabetic rats. The effects of acetonic and hexanic extracts on blood glucose were evaluated. The antagonism effect of hexanic extract on the decrease of blood glucose induced with glibenclamide and metformin was also tested. RESULTS: The hexanic extract of the leaves of V. colorata (HELVC) dose dependently increased the blood glucose in normoglycaemic rats. At the dose of 30 and 100 mg/kg, the glycaemia varied from 0.84 +/- 0.02 to 1.11 +/- 0.10 g/l and 0.68 +/- 0.02 to 1.31 +/- 0.30 g/l (p<0.05, n = 5). Such glibenclamide, the acetonic extract of the leaves of V. colorata (AELVC) induced hypoglycaemia in normoglycaemic rats. The HELVC prevents significantly the AELVC and glibenclamide induced hypoglycaemia. The chronic administration of the AELVC and HELVC as well as glibenclamide in type 1 diabetic rats did not change significantly the level of blood glucose. In type 2 diabetic rats, the single dose administration of metformin (300 mg/kg, per os) decreased the glycaemia which is completely prevented by a HELVC pretreatment. CONCLUSION: These results suggest that: i) The respective hypo- and hyperglycaemic effects of AELVC and HELVC require the presence of the pancreatic beta cells. ii) The AELVC would act by a sulfonylurea-like mechanism as glibenclamide to induce an hypoglycaemic effect.