Method optimization for a simultaneous determination of neonicotinoid, carbamate/thiocarbamate, triazole, organophosphate and pyrethroid pesticides and their metabolites in urine using UPLC-MS/MS.

An accurate and sensitive method for the determination of a total of 23 pesticides and their metabolites in human urine has been optimised. The methodology is based on a previously published method based on solid-phase extraction with methanol and acetone followed by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) in the selected reaction mode (SRM) with both positive and negative electrospray ionization (ESI+/-). The detection settings of the previous method, which allowed to determine the metabolites from 6 organophosphate and 2 pyrethroid pesticides, were optimised in order to include further pesticide groups, such as 11 neonicotinoids, 3 carbamates/thiocarbamates and 2 triazoles. The 5-windows method enduring 22 min was optimized with acceptable results in relation to accuracy (recoveries >75 %), precision (coefficients of variation <26 %) and linearity (R2> 0.9915). The limits of detection ranged between 0.012 ng/mL and 0.058 ng/mL. Samples from the German External Quality Assessment Scheme (G-EQUAS) encompassing 2 pyrethroids, 2 organophosphate and one neonicotinoid (6-chloronicotinic acid, a common metabolite of imidacloprid and acetamiprid) were analysed, and the latter, included in this newest optimization, provided good reference results. The method is optimal as a human biomonitoring tool for health risk assessment in large population surveys.

EGFR Mutation Detection in Brazilian Patients With Non-Small-Cell Lung Cancer: Lessons From Real-World Data Scenario of Molecular Testing.

PURPOSE: There is a paucity of consistent data concerning genetic mutations in Brazilian patients with lung cancer. The aim of this study was to retrospectively analyze epidermal growth factor receptor (EGFR) mutations detected in a real-world scenario using a large cohort of Brazilian patients with non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: This was a cross-sectional, observational, descriptive study on the basis of a database of EGFR molecular analysis from tumor samples of patients with a confirmatory histopathological diagnosis of primary lung cancer. Specimens were collected from 2013 to 2017 and were tested using cobas, next-generation sequencing, and Sanger sequencing platforms. RESULTS: A total of 7,413 tumor specimens were tested. The patients were predominantly women with a median age of 67.0 years. Patients with at least one mutation represented 24.2% of the total sample. Among the positive patients, the majority had just one mutation, but two or more simultaneous mutations were observed in 1.52% of patients. Exon 19 deletion was the most prevalent alteration in the sample (12.8%), followed by exon 21 L858R (6.9%) and exon 20 insertion (1.6%). All others were considered uncommon mutations and were observed in 18.5% of all mutated patients and 4.0% of the total sample (2.3%-18.7% depending on the sequencing method). CONCLUSION: This study examined the prevalence of EGFR mutations in Brazilian patients with NSCLC using different technologies, suggesting that the type of method used, directed or nondirected against specific mutations, influences the analysis, particularly for uncommon mutations, which will be missed by mutation-specific approaches such as cobas testing. Our estimates are the largest in Latin America and are consistent with previous reports from other parts of the world. Besides the variability in methods described here as technology incorporation advances in a nonhomogeneous manner, it is probably like the real-world clinical setting Brazilian oncologists face in their daily practice.

An acute bout of prolonged sitting blunts popliteal endothelium-independent dilation in young, healthy adults.

A single bout of prolonged uninterrupted sitting increases oxidative stress, reduces popliteal blood flow-induced shear stress, and diminishes endothelium-dependent, flow-mediated dilation (FMD). The FMD response is also influenced by the sensitivity of vascular smooth muscle cells to nitric oxide (i.e., endothelium-independent dilation), which is also attenuated by elevated oxidative stress. However, it is currently unknown whether prolonged sitting impacts popliteal endothelium-independent dilation responses, which may uncover a novel mechanism associated with sitting-induced vascular dysfunction. This study tested the hypothesis that prolonged sitting attenuates both popliteal FMD and endothelium-independent, nitroglycerin-mediated dilation responses (NMD, 0.4 mg sublingual dose). Popliteal blood flow (mL/min), relative FMD (%), and NMD (%) were assessed via duplex ultrasonography before and after a ∼3-h bout of sitting in 14 young, healthy adults (8♀; 22 ± 2 yr). Prolonged sitting attenuated resting blood flow (57 ± 23 to 32 ± 16 mL/min, P < 0.001), relative FMD (4.6 ± 2.8% to 2.2 ± 2.5%; P = 0.001), and NMD (7.3 ± 4.0% to 4.6 ± 3.0%; P = 0.002). These novel findings demonstrate that both endothelium-dependent and independent mechanisms contribute to the adverse vascular consequences associated with prolonged bouts of sitting.NEW & NOTEWORTHY We demonstrate that lower-limb vascular smooth muscle function is attenuated in young, healthy adults after an acute bout of prolonged sitting. These data indicate that prolonged sitting-induced vascular dysfunction involves both endothelium-dependent and -independent mechanisms.

Bioelectrical impedance vector analysis (BIVA) in stable preterm newborns.

OBJECTIVE: To observe the behavior of the plotted vectors on the RXc (R - resistance - and Xc - reactance corrected for body height/length) graph through bioelectrical impedance analysis (BIVA) and phase angle (PA) values in stable premature infants, considering the hypothesis that preterm infants present vector behavior on BIVA suggestive of less total body water and soft tissues, compared to reference data for term infants. METHODS: Cross-sectional study, including preterm neonates of both genders, in-patients admitted to an intermediate care unit at a tertiary care hospital. Data on delivery, diet and bioelectrical impedance (800 mA, 50 kHz) were collected. The graphs and vector analysis were performed with the BIVA software. RESULTS: A total of 108 preterm infants were studied, separated according to age (< 7 days and ≥ 7 days). Most of the premature babies were without the normal range (above the 95% tolerance intervals) existing in literature for term newborn infants and there was a tendency to dispersion of the points in the upper right quadrant, RXc plan. The PA was 4.92° (±2.18) for newborns < 7 days and 4.34° (±2.37) for newborns ≥ 7 days. CONCLUSION: Premature infants behave similarly in terms of BIVA and most of them have less absolute body water, presenting less fat free mass and fat mass in absolute values, compared to term newborn infants.

Análise vetorial de impedância bioelétrica (BIVA) em recém-nascidos pré-termo estáveis / Bioelectrical impedance vector analysis (BIVA) in stable preterm newborns

OBJETIVO: Observar o comportamento dos vetores ponteados no gráfico de resistência e de reactância corrigidos pelo comprimento corporal (RXc) através da análise vetorial de impedância bioelétrica (BIVA) e os valores de ângulo de fase (AF) em recém-nascidos (RNs) pré-termo estáveis, considerando a hipótese que o RN pré-termo apresenta o seu comportamento vetorial na BIVA sugestivo de menor quantidade de água e de tecidos moles corporais, comparativamente à referência do RN a termo. MÉTODOS: Foi realizado estudo de corte transversal em RNs pré-termo, de ambos os sexos, que se encontravam em uma unidade de cuidados intermediários de um hospital terciário. Coletaram-se dados relacionados ao nascimento e à alimentação, bem como dados de bioimpedância elétrica (800 mA, 50 kHz). Os gráficos e as análises vetoriais foram realizados através do BIVA software. RESULTADOS: Um total de 108 RNs pré-termo foram estudados, separados por faixa etária (< 7 dias e > 7 dias). A maioria dos RNs pré-termo encontrou-se fora da normalidade (acima dos intervalos de tolerância de 95%) existentes na literatura para RNs a termo, e observou-se uma tendência para a dispersão dos pontos no quadrante superior direito no gráfico RXc. O AF dos RNs < 7 dias foi de 4,92° (±2,18), e a dos RNs > 7 dias, de 4,34° (±2,37). CONCLUSÃO: Os RNs pré-termo se comportam de maneira semelhante entre si. A maioria deles possui menor quantidade absoluta de água corporal e apresenta menor quantidade tanto de massa livre de gordura quanto de massa gorda, em valores absolutos, quando comparados com os RNs a termo.

OBJECTIVE: To observe the behavior of the plotted vectors on the RXc (R - resistance - and Xc - reactance corrected for body height/length) graph through bioelectrical impedance analysis (BIVA) and phase angle (PA) values in stable premature infants, considering the hypothesis that preterm infants present vector behavior on BIVA suggestive of less total body water and soft tissues, compared to reference data for term infants. METHODS: Cross-sectional study, including preterm neonates of both genders, in-patients admitted to an intermediate care unit at a tertiary care hospital. Data on delivery, diet and bioelectrical impedance (800 mA, 50 kHz) were collected. The graphs and vector analysis were performed with the BIVA software. RESULTS: A total of 108 preterm infants were studied, separated according to age (< 7 days and > 7 days). Most of the premature babies were without the normal range (above the 95% tolerance intervals) existing in literature for term newborn infants and there was a tendency to dispersion of the points in the upper right quadrant, RXc plan. The PA was 4.92° (±2.18) for newborns < 7 days and 4.34° (±2.37) for newborns > 7 days. CONCLUSION: Premature infants behave similarly in terms of BIVA and most of them have less absolute body water, presenting less fat free mass and fat mass in absolute values, compared to term newborn infants.

In vitro-reduced susceptibility to artemether in P. falciparum and its association with polymorphisms on transporter genes.

Plasmodium falciparum with reduced sensitivity to artemisinin derivatives has been observed in endemic areas, but the molecular mechanisms for this reduced sensitivity remain unclear. We evaluated the association between in vitro susceptibility of P. falciparum isolates obtained from southwest Nigeria and polymorphisms in selected putative transporter genes (PFE0775C, PF13_0271, pfmrp1, pfcrt, and pfmdr1). Modified schizont inhibition assay was used to determine the in vitro parasite susceptibility to artemether (ATH). Polymorphisms in selected genes were detected by polymerase chain reaction followed by direct DNA sequencing. The half-maximal inhibitory concentration (IC(50)) geometric mean (GM) for all P. falciparum isolates was 1.78 nM (range, 0.03-10.43 nM). Polymorphisms at codons 241, 86, and 76 of PFE0775C, pfmdr1, and pfcrt genes, respectively, were associated with reduced susceptibility to ATH. A new S263P single-nucleotide polymorphism on the PFE0775C gene was also detected in 27% of the isolates. Patient isolates harboring V241L or S263P polymorphisms on the PFE0775C gene showed increased IC(50) (GM: 3.08 nM and 1.79 nM, respectively). Plasmodium falciparum isolates harboring mutant Y86 pfmdr1 and P263 PFE0775C alleles showed a 2.5-5.5-fold increase in ATH IC(50.) This study shows that polymorphisms on the PFE0775C and pfmdr1 genes are associated with reduced sensitivity to ATH in fresh isolates of P. falciparum from Nigeria.

Different patterns of pfcrt and pfmdr1 polymorphisms in P. falciparum isolates from Nigeria and Brazil: the potential role of antimalarial drug selection pressure.

The effect of antimalarial drug selection on pfcrt and pfmdr1 polymorphisms in Plasmodium falciparum isolates from two distinct geographical locations was determined in 70 and 18 P. falciparum isolates from Nigeria and Brazil, respectively, using nested polymerase chain reaction and direct DNA sequencing approaches. All isolates from Brazil and 72% from Nigeria harbored the mutant SVMNT and CVIET pfcrt haplotype, respectively. The pfcrt CVMNT haplotype was also observed in (7%) of the Nigerian samples. One hundred percent (100%) and 54% of the parasites from Brazil and Nigeria, respectively, harbored wild-type pfmdr1Asn86. We provide first evidence of emergence of the CVMNT haplotype in West Africa. The high prevalence of pfcrt CVIET and SVMNT haplotypes in Nigeria and Brazil, respectively, is indicative of different selective pressure by chloroquine and amodiaquine. Continuous monitoring of pfcrt SVMNT haplotype is required in endemic areas of Africa, where artesunate-amodiaquine combination is used for treatment of acute uncomplicated malaria.

Molecular and biological aspects of antimalarial resistance in Plasmodium falciparum and Plasmodium vivax.

The development of antimalarial drugs involving novel mechanisms of action is of imminent importance. Several potential drug candidates of synthetic and natural origin as well as their combination therapies are currently being evaluated for their efficacy against drug-resistant strains of the parasite. Various plasmodial targets/pathways, such as the Purine salvage pathway, Pyrimidine biosynthesis pathway and also the processes in the apicoplast, have been identified and are being utilized for the discovery and development of novel antimalarial therapies. This article provides an overview of the latest developments in terms of cell and molecular biology that will improve the knowledge related to drug-resistant malaria and to new molecular targets.

Patologías oftalmológicas más frecuentes en la consulta pediátrica del preescolar y escolar / More frequent ophthalmologic pathologies in the pediatric consultation of the preschool and school child

A continuación se revisarán de manera muy esquemática las patologías oculares más frecuentes en el preescolar y escolar, y también algunas patologías que si bien no son muy frecuentes, si son importantes diagnosticarlas y tratarlas precozmente, idealmente antes de los 8 años, es decir, antes de la maduración total del sistema visual, de lo contrario el pronóstico de ese niño se empobrece, su visión no alcanza una normalidad y va a terminar con una ambliopía. por lo tanto, es muy importante destacar el rol de la derivación temprana de aquellos pacientes que presentan alguna patología ocular importante como una ptosis palpebral, estrabismo o algún problema refractivo importante, entre otros, para prevenir el compromiso visual posterior.

¿Médico familiar del niño o pediatra? / Family doctor of the boy or pediatrist

La Pontificia Universidad Católica de Chile creó hace diez años el Programa de especialización en Medicina Familiar con mención en adultos y en niños. Hoy es el programa universitario que ha formado más médicos familiares en Chile. Sin embargo, desde su creación se ha planteado la interrogante si estos nuevos especialistas llenan un vacío real o están sobreponiéndose al ámbito específico de las especialidades generales tradicionales, la medicina interna y la pediatría. En este artículo se analiza esta disyuntiva referida al campo de la pediatría y la medicina familiar enfocada a los niños, a través de una descripción de los aspectos conceptuales que están involucrados, de los programas de formación y finalmente de las necesidades del país.

Programa IRA en un hospital tipo IV del Servicio de Salud Metropolitano Norte, 2003 / IRA Program in a type IV hospital of the North Metropolitan Health Service, 2003

El objetivo de este estudio es analizar el Programa IRA, según morbimortalidad y factores de riesgo (FR) de menores de un año de un hospital rural, comparándolo con cifras nacionales. Es un estudio descriptivo de todos los recién nacidos entre diciembre de 2002 y diciembre de 2003 que asisten a control sano en Hospital Til Til, categorizando fichas según score de riesgo de morir por bronconeumonía (BNM), analizando morbimortalidad y FR de cada grupo. Se analizaron 108 fichas, 17 por ciento riesgo grave de morir por BNM, 23 por ciento moderado y 60 por ciento leve, sin diferencias significativas en sexo, desarrollo psicomotor ni estado nutricional. Destacan diferencias en lactancia materna (LM) insuficiente para distintos grupos de riesgo: 66,6 por ciento severo, 44 por ciento moderado y 13,84 por ciento leve. En cuanto a morbilidad, hubo diferencias significativas en el número de episodios de SBO por niño, grupo de riesgo severo con 1,6 versus 0,96 y 0,4 moderado y leve, respectivamente. Respecto a hospitalizaciones, ocurrieron en 100 por ciento de niños en riesgo grave de morir por BNM, predominando causas respiratorias (CR) 53,8 por ciento versus 36 por ciento riesgo moderado, 75 por ciento CR. Sin diferencias significativas en perfil de morbilidad en relación con estadísticas nacionales, ya que la mayor morbilidad y hospitalizaciones se registran en grupos de mayor riesgo de morir por BNM y demuestran que el score es válido y predice efectivamente riesgo, por esto sería conveniente reforzar su aplicación en centros de salud. Hubo diferencias significativas en LM y morbilidad, importante promover LM exclusiva hasta los seis meses, destacando su rol protector.