Effects of Point Mutations in Plasmodium falciparum Dihydrofolate Reductase and Dihydropterate Synthase Genes on Clinical Outcomes and In Vitro Susceptibility to Sulfadoxine and Pyrimethamine

Sulfadoxine-pyrimethamine was a common first line drug therapy to treat uncomplicated falciparum malaria, but increasing therapeutic failures associated with the development of significant levels of resistance worldwide has prompted change to alternative treatment regimes in many national malaria control programs. METHODOLOGY AND FINDING: We conducted an in vivo therapeutic efficacy trial of sulfadoxine-pyrimethamine at two locations in the Peruvian Amazon enrolling 99 patients of which, 86 patients completed the protocol specified 28 day follow up. Our objective was to correlate the presence of polymorphisms in P. falciparum dihydrofolate reductase and dihydropteroate synthase to in vitro parasite susceptibility to sulfadoxine and pyrimethamine and to in vivo treatment outcomes. Inhibitory concentration 50 values of isolates increased with numbers of mutations (single [108N], sextuplet [BR/51I/108N/164L and 437G/581G]) and septuplet (BR/51I/108N/164L and 437G/540E/581G) with geometric means of 76 nM (35-166 nM), 582 nM (49-6890- nM) and 4909 (3575-6741 nM) nM for sulfadoxine and 33 nM (22-51 nM), 81 nM (19-345 nM), and 215 nM (176-262 nM) for pyrimethamine. A single mutation present in the isolate obtained at the time of enrollment from either dihydrofolate reductase (164L) or dihydropteroate synthase (540E) predicted treatment failure as well as any other single gene alone or in combination. Patients with the dihydrofolate reductase 164L mutation were 3.6 times as likely to be treatment failures [failures 85.4% (164L) vs 23.7% (I164); relative risk = 3.61; 95% CI: 2.14 - 6.64] while patients with the dihydropteroate synthase 540E were 2.6 times as likely to fail treatment (96.7% (540E) vs 37.5% (K540); relative risk = 2.58; 95% CI: 1.88 - 3.73). Patients with both dihydrofolate reductase 164L and dihydropteroate synthase 540E mutations were 4.1 times as likely to be treatment failures [96.7% vs 23.7%; RR = 4.08; 95% CI: 2.45 - 7.46] compared to patients having both wild forms (I164 and K540).In this part of the Amazon basin, it may be possible to predict treatment failure with sulfadoxine-pyrimethamine equally well by determination of either of the single mutations dihydrofolate reductase 164L or dihydropteroate synthase 540E.ClinicalTrials.gov NCT00951106

Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

LABORATORIO DE VIROLOGÍA EN LA PRÁCTICA CLÍNICA

Las infecciones virales continúan siendo frecuentes en la práctica clínica. Los avances en el manejo de pacientes críticos, de inmunosuprimidos y la posibilidad de ofrecer un tratamiento antiviral oportuno han exigido que el diagnóstico virológico sea hoy un servicio central dentro de los laboratorios clínicos. Un correcto y completo diagnóstico virológico permite además monitorizar pacientes con infecciones crónicas, detectar seroconversión o susceptibilidad de la población vacunada y caracterizar eventuales epidemias causadas por estos agentes. En el siguiente artículo se revisan los conceptos en los que se basan las técnicas utilizadas para el diagnóstico virológico y se entrega un resumen de los exámenes de laboratorio a solicitar ante las infecciones más frecuentes

Evaluación de migración de aluminio durante la cocción de arroz blanco en ollas de aluminio

Every day in the Ecuadorian households aluminum cooking pots are used for cooking, without knowing haw much the metallic waste that is transferred to the food. This work focused to evaluate the migration of aluminum transferred during the cooking of white rice (Oryza sativa L.) in the aluminium pots. It has warked with six types of pots from different trademarks of greater presence in the market. In these the food was cooked for 15 minutes. From each experimental unit 50.0 grams of sample were taken and, after drying, it was calcined to obtain total ashes. These were subjected to the acid digestion process. The aluminum quantification was carried by the atomic absorption technique with nitrous oxide-acetylene flame. Five sequential work cycles were carried out with each container. The results obtained were compared with the maximum permissible limit of 1 mg Al/kg of food established by the WHO and the European Union. It was observed that after the third work cycle the migration of aluminum decrease below acceptable level except in one of the samples. The study allows to conclude that the migration of this metal is decreasing with the number of uses in the experimental conditions described.Diariamente en los hogares ecuatorianos se utilizan ollas de aluminio para cocinar, sin saber la cantidad de residuos metálicos que se transfiere a los alimentos. Este trabajo evaluó la migración del aluminio en la cocción de arroz blanco (Oryza sativa L.) en recipientes de este material. Se trabajó con seis tipos de ollas, de diferentes marcas comerciales de mayor presencia en el mercado, en estas se realizó la cocción del alimento por 15 minutos. De cada unidad experimental se tomaron 50,0 gramos de muestra y, luego de secar, se calcinó para obtener cenizas totales que fueron sometidas a un proceso de digestión ácida. La cuantificación de aluminio se realizó mediante la técnica de absorción atómica con llama de óxido nitroso–acetileno. Se realizaron cinco ciclos de trabajo secuenciales con cada recipiente, los resultados obtenidos se compararon con el límite máximo permisible de 1 mg Al/kg de alimento establecido por la OMS y la Unión Europea. Se pudo observar que luego de la tercera cocción, la migración de aluminio baja hasta valores inferiores al límite máximo permisible excepto en una de las muestras. El estudio permite concluir que la migración de este metal va disminuyendo con el número de usos en las condiciones experimentales descritas

Impaired immune response in severe human lower tract respiratory infection by respiratory syncytial virus

Background: Respiratory syncytial virus (RSV) is a major cause of acute lower respiratory infection in infants. The immune response plays a leading role in the severity of the disease. We hypothesized that severe RSV disease is associated with an impaired immune response characterized by low circulating T lymphocytes and plasma cytokine concentrations. Methods: We evaluate the in vivo immune responses of previously healthy infants with their first proven RSV-acute lower respiratory infection that required hospitalization. According to the clinical severity, defined by using a strict scoring system, the in vivo immune response was compared through the analysis of plasma cytokine values and the phenotyping of peripheral blood lymphocyte and natural killer (NK) cells. Results: Absolute blood cell counts of CD4+, CD8+, and CD19+ lymphocytes and NK cells were lower in subjects with RSV than in control infants. Lowest cell counts were observed in more severe RSV-infected infants. Significan

Molecular Epidemiology of Plasmodium falciparum Malaria Outbreak, Tumbes, Peru, 2010–2012

During 2010–2012, an outbreak of 210 cases of malaria occurred in Tumbes, in the northern coast of Peru, where no Plasmodium falciparum malaria case had been reported since 2006. To identify the source of the parasite causing this outbreak, we conducted a molecular epidemiology investigation. Microsatellite typing showed an identical genotype in all 54 available isolates. This genotype was also identical to that of parasites isolated in 2010 in the Loreto region of the Peruvian Amazon and closely related to clonet B, a parasite lineage previously reported in the Amazon during 1998–2000. These findings are consistent with travel history of index case-patients. DNA sequencing revealed mutations in the Pfdhfr, Pfdhps, Pfcrt, and Pfmdr1 loci, which are strongly associated with resistance to chloroquine and sulfadoxine/pyrimethamine, and deletion of the Pfhrp2 gene. These results highlight the need for timely molecular epidemiology investigations to trace the parasite source during malaria reintroduction events