Mixed Matrix Membranes Using Porous Organic Polymers (POPs)-Influence of Textural Properties on CO2/CH4 Separation.

Mixed matrix membranes (MMMs) provide the opportunity to test new porous materials in challenging applications. A series of low-cost porous organic polymer (POPs) networks, possessing tunable porosity and high CO2 uptake, has been obtained by aromatic electrophilic substitution reactions of biphenyl, 9,10-dihydro-9,10-dimethyl-9,10-ethanoanthracene (DMDHA), triptycene and 1,3,5-triphenylbenzene (135TPB) with dimethoxymethane (DMM). These materials have been characterized by FTIR, 13C NMR, WAXD, TGA, SEM, and CO2 uptake. Finally, different loadings of these POPs have been introduced into Matrimid, Pebax, and chitosan:polyvinyl alcohol blends as polymeric matrices to prepare MMMs. The CO2/CH4 separation performance of these MMMs has been evaluated by single and mixed gas permeation experiments at 4 bar and room temperature. The effect of the porosity of the porous fillers on the membrane separation behavior and the compatibility between them and the different polymer matrices on membrane design and fabrication has been studied by Maxwell model equations as a function of the gas permeability of the pure polymers, porosity, and loading of the fillers in the MMMs. Although the gas transport properties showed an increasing deviation from ideal Maxwell equation prediction with increasing porosity of the POP fillers and increasing hydrophilicity of the polymer matrices, the behavior of biopolymer-based CS:PVA MMMs approached that of Pebax-based MMMs, giving scope to not only new filler materials but also sustainable polymer choices to find a place in membrane technology.

Intermediate risk of choledocholithiasis: are we on the right path?

The risk of choledocholithiasis should be assessed in every patient undergoing cholecystectomy to define the next step. The American Society for Gastrointestinal Endoscopy proposed a stratified predictor scale of choledocholithiasis. Therefore, we aimed to describe our experience managing patients with an intermediate risk of choledocholithiasis according to the American Society for Gastrointestinal Endoscopy guidelines and the actual presence of bile duct stones in magnetic resonance cholangiopancreatography. Methods: A retrospective observational study with a prospective database was conducted. The analysis included sociodemographic data, laboratory values, and imaging. Bivariate, multivariate, and receiver operating characteristic analysis were performed. Results: Three hundred twenty-seven patients had an intermediate risk for choledocholithiasis. Half the patients were at least 65 years old. 24.77% were diagnosed with choledocholithiasis. Bile duct dilation was documented in only 3.06% of cases. Diagnosis of choledocholithiasis is associated with an age odds ratio (OR): 1.87 (P 0.02), alkaline phosphatase OR: 2.44 (P 0.02), and bile duct dilation greater than 6 mm OR: 14.65 (P 0.00). Conclusions: High variability in the accuracy of imaging techniques results in a large number of patients classified as intermediate risk without choledocholithiasis in cholangioresonance. Therefore, enhancing the criteria to define intermediate risk for patients in order to optimize resources is of paramount importance.

Isomeric Aromatic Polyimides Containing Biphenyl Moieties for Gas Separation Applications.

An optimized synthesis of the monomer 2,2'3,3'-biphenyltetracarboxylic dianhydride, iBPDA, was performed to obtain high molecular weight polymers. This monomer has a contorted structure that produces a non-linear shape, hindering the packing of the polymer chain. Aromatic polyimides of high molecular weight were obtained by reaction with the commercial diamine 2,2-bis(4-aminophenyl) hexafluoropropane, 6FpDA, which is a very common monomer in gas separation applications. This diamine has hexafluoroisopropylidine groups which introduce rigidity in the chains, hindering efficient packing. The thermal treatment of the polymers processed as dense membranes had two targets: on the one hand, to achieve the complete elimination of the solvent used, which could remain occluded in the polymeric matrix, and on the other hand to ensure the complete cycloimidization of the polymer. A thermal treatment exceeding the glass transition temperature was performed to ensure the maximum degree of imidization at 350 °C. The good mechanical properties of these materials allow for their use in high-pressure gas purification applications. Moreover, models of the polymers exhibited an Arrhenius-like behavior characteristic of secondary relaxations, normally associated with local motions of the molecular chain. The gas productivity of these membranes was high.

Genomic alterations in a cohort of pediatric acute myeloid leukemia patients at two cancer centers in Colombia.

Few studies identifying genomic aspects in pediatric acute myeloid leukemia patients in Latin American countries have been reported. The aim of this study was to identify genomic alterations, clinical characteristics and outcomes in a cohort of pediatric AML patients. This descriptive observational cohort study included patients with confirmed de novo acute myeloid leukemia up to 18 years of age. Cytogenetics and conventional FISH analysis, next-generation sequencing and PCR testing were performed. The correlation of genomic data with treatment response and outcomes were analyzed. Of the 51 patients analyzed, 67.4% had a cytogenetic abnormality and 74.5% had a genetic variant. FLT3 variants (ITD or TKD D835) were found in 27.4%, followed by NRAS (21.6%), KRAS (13.7%) and WT1 and KIT (11.8%). Patients were stratified by risk (66.6% high-risk) after the end of induction. FLT3-ITD was associated with relapse (OR 11.25; CI 1.89-66.72, p 0.006) and NRAS with death during induction (OR 16.71; CI 1.51-184.59, p 0.022). Our study highlights the importance of rapid incorporation of genetic testing in pediatric AML in Colombia, as it directly affects treatment decisions and outcomes. Incorporation of targeted therapies with conventional chemotherapy is an increasingly urgent need in pediatric patients.

Pharmacogenetics of ABCB1, CDA, DCK, GSTT1, GSTM1 and outcomes in a cohort of pediatric acute myeloid leukemia patients from Colombia.

BACKGROUND AND AIM: Different studies have shown pharmacogenetic variants related to drug toxicity in acute myeloid leukemia (AML) patients. Our aim was to identify the association between ABCB1, CDA, DCK, GSTT1, and GSTM1 variants with clinical outcomes and toxicity in pediatric patients with AML. METHODS: Fifty-one confirmed de novo AML pediatric patients were included. A SNaPshot™ assay and conventional PCR were used to evaluate ABCB1, CDA, DCK, GSTT1, and GSTM1 variants. Clinical outcomes and toxicity associations were evaluated using odds ratios and Chi-square analysis. RESULTS: Patients carrying ABCB1 (1236C > T, rs1128503) GG genotype in had a 6.8 OR (CI 95% 1.08-42.73, p = .044) for cardiotoxicity as compared to patients carrying either AA or GA genotypes 0.14 OR (CI 95% 0.023-0.92, p = .044). For ABCB1 (1236G > A rs1128503/2677C > A/T rs2032582/3435G > A rs1045642) AA/AA/AA combined genotypes had a strong association with death after HSTC OR 13.73 (CI 95% 1.94-97.17, p = .009). Combined genotypes GG/CC/GG with CDA (79A > C, rs2072671) CA genotype or CDA (-451G > A, rs532545) CT genotype, had a 4.11 OR (CI 95% 2.32-725, p = .007) and 3.8 OR (CI 95% 2.23-6.47, p = .027) with MRD >0.1% after first chemotherapy cycle, respectively. CONCLUSION: Our results highlight the importance of pharmacogenetic analysis in pediatric AML, particularly in populations with a high degree of admixture, and might be useful as a future tool for patient stratification for treatment.

Hyperthyroidism in children and adolescents: Experience in a university hospital in Colombia / Hipertiroidismo en niños y adolescentes: experiencia en un hospital universitario en Colombia

Introduction: Hyperthyroidism is a heterogeneous condition characterized by the excessive production of thyroid hormones. It represents a diagnostic and therapeutic challenge. Objective: To describe the clinical and paraclinical characteristics and the evolution and differences between the main etiologies in patients with hyperthyroidism treated by the Pediatric Endocrinology Service at the Hospital Universitario San Vicente Fundación in Medellín, Colombia, between July 1st., 2015, and June 30th., 2020. Materials and methods: We conducted a cross-sectional observational study with retrospective data collection. Results: We included 54 patients with a mean age of 11.9 years, 72.2% of whom were female; 85.2% had no history of comorbidities related to autoimmunity; 11.1% had a family history of Graves' disease, and 29.6% of other thyroid diseases. Goiter was the most frequent clinical manifestation (83.3%) and 92.6% of the patients received treatment with methimazole, 79.6% required beta-blockers, and 11.2% additional drug therapy. Adverse drug reactions occurred in 16.7% of the patients and in 20.4% there was a resolution of hyperthyroidism (spontaneous: 9.3%; after radio-iodine ablation: 9.3%, and after surgery: 1.9%). Conclusion: Hyperthyroidism is a disease with diverse clinical manifestations. Its most frequent cause is Graves' disease followed by hashitoxicosis, which in this study had a higher frequency than that reported in the literature. The duration and side effects of pharmacological treatment were similar to those previously reported, but the higher frequency of agranulocytosis is noteworthy.

Introducción. El hipertiroidismo es una condición heterogénea caracterizada por la producción excesiva de hormonas tiroideas. Su aparición en la edad pediátrica representa un reto diagnóstico y terapéutico. Objetivo. Describir las características clínicas y paraclínicas, así como la evolución y las diferencias entre las principales causas etiológicas de los pacientes con hipertiroidismo atendidos por el Servicio de Endocrinología Pediátrica del Hospital Universitario San Vicente Fundación en Medellín, Colombia, entre el 1° de julio de 2015 y el 30 de junio de 2020. Materiales y métodos. Se hizo un estudio observacional transversal con recolección retrospectiva de la información. Resultados. Se incluyeron 54 pacientes con una edad media de 11,9 años, 72,2 % de ellos mujeres. El 11,1 % tenía antecedentes familiares de enfermedad de Graves y 29,6 % de otras enfermedades tiroideas. El bocio fue la manifestación clínica más frecuente (83,3 %). El 92,6 % había recibido terapia con metimazol, el 79,6 % requirió betabloqueador y el 11,2 % necesitó una terapia farmacológica adicional. Se presentaron reacciones adversas a la medicación en el 16,7 %. En el 20,4 % de los pacientes hubo resolución del hipertiroidismo (espontánea: 9,3 %; posterior a la ablación con yodo radiactivo: 9,3 %, y después de la cirugía: 1,9 %). Conclusión. El hipertiroidismo es una enfermedad con manifestaciones clínicas diversas. La causa más frecuente es la enfermedad de Graves, seguida por la hashitoxicosis. En este estudio, la hashitoxicosis fue más frecuente que en estudios previos. La duración y los efectos secundarios del tratamiento farmacológico fueron similares a los reportados previamente, pero es de resaltar la mayor frecuencia de agranulocitosis en nuestra población.

Preeclampsia, Natural History, Genes, and miRNAs Associated with the Syndrome.

Preeclampsia (PE) is a hypertensive disease that affects pregnant women after 20 weeks of gestation. This disease is associated with an important risk of maternal and fetal mortality. PE is described as a placental pathology because, after delivery, most women recover normal arterial pressure. Poor invasion of the spiral arteries is a phenomenon well described in PE; this leads to a hypoxic uterine bed and imbalance of antiangiogenic and proangiogenic factors in the uteroplacental region, which in turn triggers the disease phenotype. The causes of the pathology are unclear; nevertheless, numerous approaches, including next-generation sequencing, association, and case control and miRNA studies, have shed light on the genetic/molecular basis of PE. These studies help us better understand the disease to advance new treatment strategies.

Morbimortality assessment in abdominal surgery: are we predicting or overreacting?

BACKGROUND: High-risk surgical procedures represent a fundamental part of general surgery practice due to its significant rates of morbidity and mortality. Different predictive tools have been created in order to quantify perioperative morbidity and mortality risk. POSSUM (Physiological and Operative Severity Score for the enumeration of Mortality and morbidity) is one of the most widely validated predictive scores considering physiological and operative variables to precisely define morbimortality risk. Nevertheless, seeking greater accuracy in predictions P-POSSUM was proposed. We aimed to compare POSSUM and P-POSSUM for patients undergoing abdominal surgery. METHODS: A retrospective observational study with a prospective database was conducted. Patients over 18 years old who complied with inclusion criteria between 2015 and 2016 were included. Variables included in the POSSUM and P-POSSUM Scores were analyzed. Descriptive statistics of all study parameters were provided. The analysis included socio-demographic data, laboratory values ​​, and imaging. Bivariate analysis was performed. RESULTS: 350 Patients were included in the analysis, 55.1% were female. The mean age was 55.9 ± 20.4 years old. POSSUM revealed a moderated index score in 61.7% of the patients, mean score of 12.85 points ± 5.61. 89.1% of patients had no neoplastic diagnosis associated. Overall morbidity and mortality rate was 14.2% and 7.1%. P-POSSUM could predict more precisely mortality (p < 0.00). CONCLUSIONS: The POSSUM score is likely to overestimate the risk of morbidity and mortality in patients with high/moderate risk, while the P-POSSUM score seems to be a more accurate predictor of mortality risk. Further studies are needed to confirm our results.

Analysis of Linguistically and Culturally Tailored Initiatives in Websites of Kidney Transplant Programs in the United States Between 2013-2018.

INTRODUCTION: Minority patients constitute the majority of the kidney transplant waiting list, yet they suffer greater difficulties in listing and longer wait times to transplantation. There is a lack of information regarding targeted efforts by transplant centers to improve transplant care for minority populations. RESEARCH QUESTION: Our aim was to analyze all kidney transplant websites in the United States to identify changes over a 5-year period in the number of multilingual websites, reported culturally targeted initiatives, and center and provider diversity. DESIGN: Surveys were developed to analyze center websites of all transplant programs in the United States. Those with incomplete information about their nephrology or surgical teams were excluded, resulting in 174 (73%) sites in 2013 and 185 (76%) in 2018. Results: Few websites were available in a language other than English, 6.3% in 2013 and 9.7% in 2018 (P = 0.24). Only 3 websites (1.3%) in 2013 and 7 (3.7%) in 2018 reported any evidence of a culturally targeted initiative (P = 0.23). In 2018, 35% of centers employed a Hispanic transplant physician, 77% had a transplant physician who spoke a language other than English, and 39% had a transplant physician who spoke Spanish. DISCUSSION: Although minority patients are expected to grow in the United States, decreased access to transplantation continues to vex the transplant community. Very little progress has been made in the development of multilingual websites and culturally targeted initiatives.

Identifying new potential genetic biomarkers for HELLP syndrome using massive parallel sequencing.

BACKGROUND: Preeclampsia (PE) is a frequently occurring multisystemic disease affecting ~5% of pregnancies. PE patients may develop HELLP syndrome (haemolysis, elevated liver enzymes, and low platelet), a mother and foetus life-threatening condition. Research into HELLP's genetic origin has been relatively unsuccessful, mainly because normal placental function and blood pressure regulation involve the fine-regulation of hundreds of genes. OBJECTIVE: To identify new genes and mutations constituting potential biomarkers for HELLP syndrome. STUDY DESIGN: The present case-control study involved whole-exome sequencing of 79 unrelated HELLP women. Candidate variants were screened in a control population constituted by 176 individuals. Stringent bioinformatics filters were used for selecting potentially etiological sequence variants in a subset of 487 genes. We used robust in silico mutation modelling for predicting the potential effect on protein structure. RESULTS: We identified numerous sequence variants in genes related to angiogenesis/coagulation/blood pressure regulation, cell differentiation/communication/adhesion, cell cycle and transcriptional gene regulation, extracellular matrix biology, lipid metabolism and immunological response. Five sequence variants generated premature stop codons in genes playing an essential role in placental physiology (STOX1, PDGFD, IGF2, MMP1 and DNAH11). Six variants (ERAP1- p.Ile915Thr, ERAP2- p.Leu837Ser, COMT-p.His192Gln, CSAD-p.Pro418Ser, CDH1- p.Ala298Thr and CCR2-p.Met249Lys) led to destabilisation of protein structure as they had significant energy and residue interaction-related changes. We identified at least two mutations in 57% of patients, arguing in favour of a polygenic origin for the HELLP syndrome. CONCLUSION: Our results provide novel evidence regarding PE/HELLP's genetic origin, leading to new biomarkers, having potential clinical usefulness, being proposed.

Desenlaces materno-fetales de los embarazos atendidos en el Hospital Universitario de Santander, Bucaramanga (Colombia), 2007-2011. Estudio de cohorte / Maternal and foetal outcomes in twin pregnancies seen at Hospital Universitario de Santander, Bucaramanga (Colombia), 2007-2011. A cohort study

Los embarazos gemelares implican mayor riesgo de complicaciones materno-fetales que los embarazos únicos, particularmente en los monocoriales. El objetivo del trabajo fue describir las características clínicas y los desenlaces materno-fetales, por tipo de placenta (monocorial o bicorial), de los embarazos gemelares atendidos en el Hospital Universitario de Santander (HUS), institución de tercer nivel de complejidad localizada en Bucaramanga (Colombia). Materiales y métodos: estudio descriptivo de cohorte, se incluyeron las pacientes que terminaron un embarazo gemelar entre 2007 y 2011 en el HUS, hospital general de referencia de la región centro-oriental del país. Muestreo consecutivo. Se evaluó la edad gestacional en la primera consulta al hospital, los hallazgos clínicos en la evaluación inicial, la terminación del parto y los resultados perinatales. Se hace análisis descriptivo por tipo de corionicidad. Resultados: se incluyeron un total de 248 gestantes con embarazo gemelar en el periodo de estudio. La mediana de la edad gestacional en la primera atención en el hospital en fue de 34 semanas. Al ingreso, 127 (51,2 %) pacientes se diagnosticaron con embarazo monocorial, pero solo en dos terceras partes coincidió el diagnóstico prenatal de corionicidad con el del posparto. Se diagnosticó RCIU con más frecuencia en embarazos monocoriales que en bicoriales (22,3 vs. 7,5 %), y el doppler se encontró alterado con mayor frecuencia en fetos de embarazo monocorial (7,8 vs. 1,1 %). Los neonatos > 24 semanas de edad gestacional de embarazo monocorial pesaron, en promedio, 109 g (IC 95 %: 34-184) menos que los bicoriales. Conclusiones: los resultados de este estudio sugieren un problema de salud pública en este grupo de pacientes, con inicio tardío de control prenatal, de remisión tardía a centros especializados y capacidad insuficiente para definir corionicidad. Se requiere plantear estrategias de atención que incluyan considerar los embarazos gemelares como alto riesgo y garantizar la atención oportuna y adecuada, orientada por una guía de cuidado diferencial para este grupo de gestantes...

Twin pregnancies, especially monochorionic placentations, are associated with a higher rate of maternal and foetal complications when compared to singleton pregnancies. The objective of this work was to describe the clinical characteristics and the maternal and foetal outcomes according to the type of placentation (monochorial or dichorial) of twin pregnancies delivered at Hospital Universitario de Santander (HUS), a level III institution located in Bucaramanga, Colombia. Materials and methods: Descriptive cohort study. The cohort consisted of patients delivered of a twin pregnancy between 2007 and 2011 at the HUS, a general referral hospital for the central-eastern region of the country. The assessment included gestational age at the time of initial presentation to the hospital, clinical findings during the initial assessment, delivery completion, and perinatal results. Descriptive analysis by chorionicity type. Results: A total of 248 women with a twin pregnancy during the study period were included. The mean gestational age on the first visit to the hospital was 34 weeks. On admission, 127 patients (51.2%) were diagnosed with a monochorionic pregnancy, but only in two thirds of the cases was the prenatal chorionicity diagnosis consistent with the post-partum finding. IUGR was diagnosed more frequently in monochorionic than in dichorionic pregnancies (22.3% v. 7.5%) and abnormal Doppler findings were more frequent in monochorionic foetuses (7.8% v. 1.1%). Neonates > 24 of gestational age in monochorionic pregnancies weigh in average 109 gr (IC 95%: 34-184) less than dichorionic twins. Conclusions: The results of this study suggest a public health problem in this group of patients who come late for their prenatal visits and are late referrals to specialized centres, when there is already a limited ability to determine chorionicity. There is a need to develop care strategies in which twin pregnancies are included as a high-risk condition, and to ensure timely and adequate care provision in accordance with differential care guidelines for this group of pregnant women...

The tomato borer, Tuta absoluta, invading the Mediterranean Basin, originates from a single introduction from Central Chile.

The Lepidopteran pest of tomato, Tuta absoluta, is native to South America and is invasive in the Mediterranean basin. The species' routes of invasion were investigated. The genetic variability of samples collected in South America, Europe, Africa and Middle East was analyzed using microsatellite markers to infer precisely the source of the invasive populations and to test the hypothesis of a single versus multiple introductions into the old world continents. This analysis provides strong evidence that the origin of the invading populations was unique and was close to or in Chile, and probably in Central Chile near the town of Talca in the district of Maule.

Factores individuales, familiares y escolares asociados a la aceptación y el rechazo social en grupos de niños escolarizados entre los 9 y 11 años de edad / Individual, familiar and scholastic factors associated to the acceptance and the social rejection in groups of escolarizados children between the 9 and 11 years of age

Este artículo es un avance del estudio que busca identificar variables individuales, familiares y escolares asociadas con la aceptación y el rechazo en grupos escolaresde niños entre 9 y 11 años de edad. Se considerandos tipos de variables individuales: los déficit y excesos conductuales y las estrategias de procesamiento de informaciónsocial. Como variables familiares se tienen cinco estilos de crianza: autoritario, permisivo, descuidado,sobreprotector y democrático. En el contexto escolar se tienen en cuenta tres estilos pedagógicos: el autoritario, el permisivo y el democrático. También se quiere detectar las percepciones que comparten los niños sobre actitudes que hacen a un compañero merecedorde rechazo o aceptación en su grupo escolar. Para la recolección de los datos se diseñaron cuestionarios y entrevistas semiestructuradas que se aplicarán principalmentea los niños. Los datos obtenidos serán sometidosa análisis estadístico correlacional y en algunos casos, a análisis de contenido...