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Magnetite (Fe3O4) nanoparticles were synthesized by the ultrasound assisted co-precipitation method. The synthesized nanoparticles were thoroughly characterized by various analytical tools including XRD, FESEM & TEM, VSM, BET, and FTIR. It was indicated that Fe3O4 nanoparticles have cubic structure. The size of spherical-shape Fe3O4 particles ranges from 10 to 15 nm. The Fe3O4 magnetic nanoparticles were applied as a magnetic adsorbent to remove Congo red from aqueous solution. It is assumed that the adsorption process follows the pseudo-second-order kinetics equation. Equilibrium data fits well with Langmuir model. The maximum adsorption capacity is of 169.8 mg/g. This suggests that the synthesized magnetic nanoparticles could be a promising adsorbent for organic dyes removal in aqueous solutions.

Sokleaph Cheng,1– 3 Mallorie Hide,3– 5 Sok Heng Pheng,6 Alexandra Kerléguer,2 Gauthier Delvallez,2 Sophan Sam,7 Tan Eang Mao,6 Thi Van Anh Nguyen,3,8 Anne-Laure Bañuls3– 5 1Institut Pasteur du Cambodge and Ministry of Health, Phnom Penh, Cambodia; 2Medical Biology Laboratory, Institut Pasteur du Cambodge, Phnom Penh, Cambodia; 3LMI Drug Resistance in South East Asia, Institut Pasteur du Cambodge, Phnom Penh, Cambodia; 4MIVEGEC, University of Montpellier, Institute of Research for Development, Centre National de la Recherche Scientifique, Montpellier, France; 5CREES (Centre de Recherche En Écologie Et Évolution de la Santé), Montpellier, France; 6National Center for Tuberculosis and Leprosy Control, Phnom Penh, Cambodia; 7Cambodian Health Committee, Phnom Penh, Cambodia; 8Department of Bacteriology, National Institute of Hygiene and Epidemiology, Hanoi, Martinique, VietnamCorrespondence: Sokleaph ChengInstitut Pasteur du Cambodge, No. 5, Monivong Boulevard, Phnom Penh 120210, CambodiaTel +855 12 222 684Email csokleaph@pasteur-kh.orgBackground: Due to the emergence of Mycobacterium tuberculosis (M.tb) clinical isolates resistant to most potent first-line drugs (FLD), second-line drugs (SLD) are being prescribed more frequently. We explore the genetic characteristics and molecular mechanisms of M.tb isolates phenotypically resistant to SLD, including pre-extensively drug-resistant (pre-XDR) and extensively drug-resistant (XDR) isolates.Methods: Drug-resistant (DR) M.tb isolates collected from 2012 to 2017 were tested using sequencing and phenotypic drug susceptibility testing. Genotypes were determined to explore their links with SLD resistance patterns.Results: Of the 272 DR M.tb isolates, 6 non-multidrug resistant (non-MDR) isolates were fluoroquinolones (FQ)-resistant, 3 were XDR and 16 were pre-XDR (14 resistant to FQ and 2 to second-line injectable drugs). The most frequent mutations in FQ-resistant and second-line injectable drugs resistant isolates were gyrA D94G (15/23) and rrs a1401g (3/5), respectively. Seventy-five percent of pre-XDR isolates and 100% of XDR isolates harbored mutations conferring resistance to pyrazinamide. All XDR isolates belonged to the Beijing genotype, of which one, named XDR+, was resistant to all drugs tested. One cluster including pre-XDR and XDR isolates was observed.Conclusion: This is the first description of SLD resistance in Cambodia. The data suggest that the proportion of XDR and pre-XDR isolates remains low but is on the rise compared to previous reports. The characterization of the XDR+ isolate in a patient who refused treatment underlines the risk of transmission in the population. In addition, genotypic results show, as expected, that the Beijing family is the main involved in pre-XDR and XDR isolates and that the spread of the Beijing pre-XDR strain is capable of evolving into XDR strain. This study strongly indicates the need for rapid interventions in terms of diagnostic and treatment to prevent the spread of the pre-XDR and XDR strains and the emergence of more resistant ones.Keywords: Mycobacterium tuberculosis, extensively drug-resistant tuberculosis, pre-extensively drug-resistant tuberculosis, fluoroquinolone, second-line injectable drugs

Visceral vasculitis is a well‐described manifestation of systemic lupus erythematosus (SLE) [1]. Here, we report an unusual case of a male patient with long‐standing chronic discoid lupus erythemat...

This paper describes current trends in the HIV/AIDS epidemic. It looks at issues and strategies involved in educating women about HIV/AIDS in the context of the global pandemic, focusing particularly on Canada and Vietnam. These strategies are essential steps in preventing the spread of HIV and in caring for those who have already developed AIDS. The strategies identified include the formulation of public policy within Canada, Vietnam, and the UK which would strive to eliminate inequality and discrimination, while at the same time positioning HIV/AIDS education within a gender‐sensitive perspective. Other educational strategies include teaching women how to practise negotiated safety while understanding the power dynamics within which safer sex must occur, being sensitive to local cultures and moving away from individualistic programmes towards programmes that focus on structural inequalities.