199 research outputs found
Minimal dataset for the research "Outbreaks of COVID-19 in a tuberculosis treatment sanatorium on the Thailand-Myanmar border: a retrospective cohort analysis"
No full text<p><strong>Outbreaks of COVID-19 in a tuberculosis treatment sanatorium on the Thailand-Myanmar border: a retrospective cohort analysis:</strong></p><p><strong>Latest Version Published: </strong>22 Jun 2023, <strong>8</strong>:272 (<a href="https://doi.org/10.12688/wellcomeopenres.19275.1">https://doi.org/10.12688/wellcomeopenres.19275.1</a>)</p><p>This is an open access work distributed under the terms of the <a href="https://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution License</a>, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</p>
KINETICS OF SCANDIUM SORPTION BY IMPREGNATE CONTAINING PHOSPHINOXIDE
No full textThe kinetics of scandium sorption with impregnate-containing extractant – phosphine oxide based on hypercrosslinked polystyrene from nitric acid solutions was studied using a method of limited solution volume. A sample of sorbent obtained by impregnation contained 0.233 g extractant/g impregnate. Under batch conditions, the influence of temperature in the range 293-313 K on the kinetics of scandium sorption by impregnate was studied. It was revealed that the saturation of impregnate by scandium is established in 20-30 min. For the processing of integral kinetic scandium sorption curves, the pseudo-first and pseudo-second-order models, as well as the Elovich equation, were used. The values of the rate constants calculated from the pseudo-second-order model, describing the kinetic data with the best correlation coefficients (R2 0.931-0.995), reach (9.51-10.4) g∙(mmol∙min)-1. The activation energy of scandium sorption, calculated by an equation similar to the Arrhenius equation, is (2.8±0.2) kJ / mol. Due to the improved kinetic characteristics compared with traditional sorbents, hypercrosslinked polystyrene impregnates containing phosphine oxide can be used to extract of scandium from solutions formed during the processing of scandium-containing raw materials.Forcitation:Pyae Phyo Aung, Veselova O.A., Troshkina I.D. Kinetics of scandium sorption by impregnate containing phosphinoxide. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 8. P. 28-30.</jats:p
Defining the optimal management of Plasmodium falciparum malaria on a background of emerging artemisinin combination therapy resistance
No full textDrug resistant falciparum malaria has emerged twice from the Thai-Cambodian border and spread to the rest of the globe with disastrous consequences. The deployment of artemisinin-based combination therapy (ACT) as first-line treatment for P. falciparum malaria has reduced the burden of malaria dramatically worldwide and reignited the interest in the goal of malaria elimination. However, slow-clearing parasites resistant to artemisinin are emerging across the Greater Mekong Sub-region eventually leading to the failure of the ACTs.
One objective of this thesis was to determine the association between therapeutic efficacy of one of the first line ACTs (mefloquine-artesunate) and the drug-resistant molecular markers for the constituent drugs (Pfmdr-1 and K-13 mutations). Between 2003 and 2013, the adequate clinical and parasitological response to mefloquine-artesunate declined from 100% to 81.1% as the proportions of isolates with multiple Pfmdr-1 copies doubled from 32.4% to 64.7% and those with K-13 mutations increased from 6.7% to 83.4%. Detailed investigations of the various K-13 polymorphisms revealed that along the ThailandâMyanmar border, the fittest alleles (C580Y) are taking over from less resistant or less fit ones.
The second objective of this thesis was to evaluate new antimalarials (OZ439, a synthetic peroxide structurally related to artemisinin; KAE609, a spironindolone; and KAF156, an imidazolopiperazine, both are structurally novel molecules) in Phase 2a proof-of-concept studies. Parasitological efficacy was evaluated by measuring parasite clearance half-life. In all trialled doses of OZ439, KAE609 and KAF156 parasite clearance half-lives were not different in patients with artemisinin-sensitive and artemisinin-resistant parasites. No serious drug-related adverse effects were reported and these compounds will move into Phase 2b studies in late 2016.</p
Reply to Hastings, et al., and Meshnick.
No full textA response to the comments of Professor Meshnik and Dr Hastings on the paper "Phyo, A.P., et al., Declining Efficacy of Artemisinin Combination Therapy Against P. Falciparum Malaria on the Thai–Myanmar Border (2003–2013): The Role of Parasite Genetic Factors. Clinical Infectious Diseases, 2016.
Challenges to replace ACT as first-line drug
No full textAbstract The spread of artemisinin and partner drug resistance through Asia requires changes in first-line therapy. The traditional modus has been the replacement of one first-line anti-malarial regimen with another. The number of anti-malarial drug candidates currently in development may have given false confidence in the expectation that resistance to artemisinin-based combination therapy (ACT) can be solved with a switch to the next anti-malarial drug regimen. A number of promising anti-malarial drug regimens did not succeed in becoming first-line drugs due to safety concerns or rapid development of resistance. Currently promising candidates for inclusion in first-line regimens, such as KAE 609, KAF 156, OZ 439, and OZ 277, have already triggered safety concerns or fears that point mutations could render the drugs inefficacious. An additional challenge for a new first-line drug is finding an appropriate partner drug. There is hope that none of the above-mentioned concerns will be substantiated in larger, upcoming trials. Meanwhile, combining already licensed anti-malarials may be a promising stop-gap measure. Practitioners in Vietnam have empirically started to add mefloquine to the current dihydroartemisinin-piperaquine. Practitioners in Africa could do worse than empirically combine already licensed co-artemether and amodiaquine when treatment with ACT no longer clears Plasmodium falciparum. Both combinations are currently undergoing trials
Clinical impact of vivax malaria: a collection review
No full textBackground
Plasmodium vivax infects an estimated 7 million people every year. Previously, vivax malaria was perceived as a benign condition, particularly when compared to falciparum malaria. Reports of the severe clinical impacts of vivax malaria have been increasing over the last decade.
Methods and findings
We describe the main clinical impacts of vivax malaria, incorporating a rapid systematic review of severe disease with meta-analysis of data from studies with clearly defined denominators, stratified by hospitalization status. Severe anemia is a serious consequence of relapsing infections in children in endemic areas, in whom vivax malaria causes increased morbidity and mortality and impaired school performance. P. vivax infection in pregnancy is associated with maternal anemia, prematurity, fetal loss, and low birth weight. More than 11,658 patients with severe vivax malaria have been reported since 1929, with 15,954 manifestations of severe malaria, of which only 7,157 (45%) conformed to the World Health Organization (WHO) diagnostic criteria. Out of 423 articles, 311 (74%) were published since 2010. In a random-effects meta-analysis of 85 studies, 68 of which were in hospitalized patients with vivax malaria, we estimated the proportion of patients with WHO-defined severe disease as 0.7% [95% confidence interval (CI) 0.19% to 2.57%] in all patients with vivax malaria and 7.11% [95% CI 4.30% to 11.55%] in hospitalized patients. We estimated the mortality from vivax malaria as 0.01% [95% CI 0.00% to 0.07%] in all patients and 0.56% [95% CI 0.35% to 0.92%] in hospital settings. WHO-defined cerebral, respiratory, and renal severe complications were generally estimated to occur in fewer than 0.5% patients in all included studies. Limitations of this review include the observational nature and small size of most of the studies of severe vivax malaria, high heterogeneity of included studies which were predominantly in hospitalized patients (who were therefore more likely to be severely unwell), and high risk of bias including small study effects.
Conclusions
Young children and pregnant women are particularly vulnerable to adverse clinical impacts of vivax malaria, and preventing infections and relapse in this groups is a priority. Substantial evidence of severe presentations of vivax malaria has accrued over the last 10 years, but reporting is inconsistent. There are major knowledge gaps, for example, limited understanding of the underlying pathophysiology and the reason for the heterogenous geographical distribution of reported complications. An adapted case definition of severe vivax malaria would facilitate surveillance and future research to better understand this condition
PRISMA checklist.
No full textPRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses. (DOCX)</p
Estimating mortality in studies eligible for inclusion in the meta-analysis.
No full textEstimating mortality in studies eligible for inclusion in the meta-analysis.</p
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