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1.
World J Pediatr Congenit Heart Surg ; 15(2): 226-230, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37990527

RESUMO

Patients with hypoplastic left heart syndrome (HLHS) with intact atrial septum have an increased mortality rate. This presentation occurs in 6% to 10% of cases. We present a patient with fetal diagnosis of HLHS with restrictive atrial septum. We performed a cesarean section at 37 weeks of gestation, and under ex utero intrapartum treatment proceeded with a median sternotomy and transatrial stenting for left atrial decompression due to findings of intact atrial septum on the fetal echocardiogram performed during the procedure. Subsequently, the patient underwent hybrid stage I palliation followed by a comprehensive stage II procedure at five months of age, but unfortunately died from postoperative complications.


Assuntos
Septo Interatrial , Síndrome do Coração Esquerdo Hipoplásico , Humanos , Gravidez , Feminino , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Cesárea , Átrios do Coração/cirurgia , Diagnóstico Pré-Natal , Resultado do Tratamento , Estudos Retrospectivos
2.
Innovations (Phila) ; 17(6): 557-561, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36571265

RESUMO

Single-ventricular cardiopathies are challenging conditions requiring multiple surgical interventions to hopefully achieve adulthood. In neonates, pulmonary artery banding allows ventricular adaptation and pulmonary vascular bed protection. Here we present a novel minimally invasive approach to pulmonary artery banding through a 1.5 cm left parasternal minithoracotomy. This technique not only allows for a less traumatic first procedure but also a less manipulated mediastinum and untouched sternum for the consequent surgeries to come. This technique is reproducible in experienced hands and shows favorable and promising results when performed properly.


Assuntos
Artéria Pulmonar , Procedimentos Cirúrgicos Vasculares , Recém-Nascido , Humanos , Adulto , Artéria Pulmonar/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Toracotomia/métodos , Esterno/cirurgia , Mediastino/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
3.
Chemphyschem ; 23(11): e202200152, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35481907

RESUMO

There is an ongoing effort to replace rare and expensive noble-element catalysts with more abundant and less expensive transition metal oxides. With this goal in mind, the intrinsic defects of a rhombohedral perovskite-like structure of LaMnO3 and their implications on CO catalytic properties were studied. Surface thermodynamic stability as a function of pressure (P) and temperature (T) were calculated to find the most stable surface under reaction conditions (P=0.2 atm, T=323 K to 673 K). Crystallographic planes (100), (111), (110), and (211) were evaluated and it was found that (110) with MnO2 termination was the most stable under reaction conditions. Adsorption energies of O2 and CO on (110) as well as the effect of intrinsic defects such as Mn and O vacancies were also calculated. It was found that O vacancies favor the interaction of CO on the surface, whereas Mn vacancies can favor the formation of carbonate species.

4.
Philos Trans A Math Phys Eng Sci ; 379(2209): 20200346, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34510929

RESUMO

The hydrodeoxygenation (HDO) of acetophenone was evaluated in liquid phase and gas phase over monometallic Pt/SiO2, Co/SiO2 and bimetallic Pt-Co/SiO2 catalysts. The influence of reaction time and loading of the catalyst were analysed by following the conversion and products selectivity. Phenylethanol, cyclohexylethanone and cyclohexylethanol are the main products of reaction using the Pt/SiO2 catalyst. By contrast, ethylbenzene and phenylethanol are the only products formed on the Co/SiO2 and Pt-Co/SiO2 catalysts. The bimetallic catalyst is more stable as a function of time and more active towards the HDO process than the monometallic systems. The presence of an organic solvent showed only minor changes in product yields with no effect on the product speciation. Periodic density functional theory analysis indicates a stronger interaction between the carbonyl group of acetophenone with Co than with Pt sites of the mono and bimetallic systems, indicating a key activity of oxophilic sites towards improved selectivity to deoxygenated products. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)'.

5.
J Clin Neurosci ; 88: 159-162, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33992177

RESUMO

Botulism is a life-threatening presynaptic disorder of the neuromuscular transmission produced by the neurotoxin elaborated by the botulinum neurotoxin-producing clostridia. We describe the management of a case series of 14 patients, members of 5 different families that were exposed to home-canned tuna and developed symptoms compatible with a mild clinical presentation of foodborne botulism. The electrophysiological study of the index case represented a reliable diagnostic test as it demonstrated a slight presynaptic dysfunction of the neuromuscular junction. Definite diagnosis was later confirmed by microbiological tests. Out of 14, only 3 patients presenting with a shorter period from symptom onset and with signs of multiple cranial neuropathies received botulinum antitoxin. All the patients remained stable and recovered progressively. Treatment with antitoxin may not be necessary in patients with late-presenting disease and mild and stable clinical picture.


Assuntos
Antitoxina Botulínica/uso terapêutico , Botulismo/diagnóstico , Botulismo/terapia , Tratamento Conservador/métodos , Adolescente , Adulto , Clostridium botulinum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
J Phys Chem A ; 124(35): 7080-7087, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32786982

RESUMO

Considering that a molecular-level understanding of the azeotropic ethanol-water system can contribute to the search of new methodologies and/or modifications of industrial separation methods, this study tries to provide some clues to understand why azeotropes should be expected for ethanol, but not for methanol. Our exploration of the potential energy surface of (ethanol)6-water heteroheptamers, carried out at the B3LYP-D3/6-311++G(d,p) level, shows these heteroclusters to exhibit a cyclic structure where the cooperativity effects between the OH···O HBs is a fundamental ingredient. An analysis of this cooperativity clearly indicates that ethanol-water systems will exhibit a similarly high stability as the heterocluster size approaches the azeotrope. However, a similar behavior should not be expected for the methanol-containing analogues. A comparison between (ethanol)7, (ethanol)6-water, (methanol)7, and (methanol)6-water shows the ethanol-containing systems to be significantly more stable than the methanol-containing analogues. This result is probably due to the fact that the OH···O HBs are weaker than those found between ethanol molecules. However, our atoms in molecule (AIM) and noncovalent interaction (NCI) analyses unambiguously show that important contributors to the enhanced stability of the ethanol-containing clusters are the secondary van der Waals interactions between ethyl groups, which are not observed between methyl groups. Hence, while the formation of stable azeotropes is expected for the case of ethanol, for the methanol-containing analogues, the relative stability of the clusters is significantly smaller, and its formation is accompanied by an increase of the free energy.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32106710

RESUMO

Objective: To perform a comprehensive lipid profiling to evaluate potential lipid metabolic differences between patients with amyotrophic lateral sclerosis (ALS) and controls, and to provide a more profound understanding of the metabolic abnormalities in ALS. Methods: Twenty patients with ALS and 20 healthy controls were enrolled in a cross-sectional study. Untargeted lipidomics profiling in fasting serum samples were performed by optimized UPLC-MS platforms for broad lipidome coverage. Datasets were analyzed by univariate and a variety of multivariate procedures. Results: We provide the most comprehensive blood lipid profiling of ALS to date, with a total of 416 lipids measured. Univariate analysis showed that 28 individual lipid features and two lipid classes, triacylglycerides and oxidized fatty acids (FAs), were altered in patients with ALS, although none of these changes remained significant after multiple comparison adjustment. Most of these changes remained constant after removing from the analysis individuals treated with lipid-lowering drugs. The non-supervised principal component analysis did not identify any lipid clustering of patients with ALS and controls. Despite this, we performed a variety of linear and non-linear supervised multivariate models to select the most reliable features that discriminate the lipid profile of patients with ALS from controls. These were the monounsaturated FAs C24:1n-9 and C14:1, the triglyceride TG(51:4) and the sphingomyelin SM(36:2). Conclusions: Peripheral alterations of lipid metabolism are poorly defined in ALS, triacylglycerides and certain types of FAs could contribute to the different lipid profile of patients with ALS. These findings should be validated in an independent cohort.


Assuntos
Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/diagnóstico , Lipidômica/métodos , Espectrometria de Massas em Tandem/métodos , Idoso , Cromatografia Líquida de Alta Pressão/métodos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Mol Model ; 25(1): 26, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30612236

RESUMO

Furfural is a valuable oxygenated compound derived from the thermal decomposition of biomass, and is one of the major problems of bio-oil upgrading. Due to its high reactivity, this compound requires further upgrading to more stable products such as furfuryl alcohol, 2-methylfuran (MF), furan, 2-methyltetrahydrofuran, and tetrahydrofuran. The thermochemical data and kinetic analysis of the reactions involved in the conversion of furfural were investigated by molecular modeling to guide experimental investigations in the process of designing efficient catalysts that allows the control of the reaction pathways in specific directions, towards the production of fuel precursors or chemicals. All calculations for reactants, intermediates, and products were performed using the long range corrected functional WB97XD, with the basis set 6-311+g(d,p), under the density functional theory framework. Thermochemistry results suggest that furfural hydrogenation to form furfuryl alcohol is spontaneous up to a temperature of 523 K, but beyond this temperature the reaction becomes a nonspontaneous process. By contrast, the decarbonylation of furfural was thermodynamically favored at temperatures greater than 523 K. Therefore, furan is a thermodynamically favored product, while furfuryl alcohol is kinetically preferred. Once furfuryl alcohol is formed, the hydrogenolysis path to produce methylfuran is favored kinetically and thermodynamically, compared to the ring-hydrogenation towards tetrahydrofurfuryl alcohol. Gas phase thermodynamic properties and rate constants of the reactions involved in the conversion of furfural were calculated and compared against existing experimental data. This study provides the basis for further vapor phase catalytic studies required for upgrading of furans/furfurals to value-added chemicals. Graphical abstract Furan is a thermodynamically favored product, while furfuryl alcohol is kinetically preferred.

9.
Neurology ; 87(12): 1250-7, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27558368

RESUMO

OBJECTIVE: Describe the incidence of cancer in a large cohort of patients with myotonic dystrophy type 1 (DM1) and to unravel the underlying molecular mechanisms. METHODS: Standardized incidence ratios (SIRs) were calculated in the Gipuzkoa DM1 cohort (1985-2013), dividing observed numbers by expected numbers for all cancers combined and stratified by sex. An estimation of the expected incidence was achieved by multiplying the age- and sex-specific incidence rates from the Basque population cancer registry by the person-years observed in the study cohort. Large-scale gene expression of peripheral blood mononuclear cell samples derived from 10 individuals with DM1 (5 men, 5 women) and 10 healthy matched controls was analyzed by the Human Gene 1.0 ST Affymetrix microarray. RESULTS: During 18,796 person-years of follow-up, corresponding to 424 patients with DM1, we observed 70 cancers in 62 patients giving a 1.81-fold risk (95% confidence interval [CI] 1.37-2.36), which was stronger in women than in men. Ovary (SIR 8.33, 95% CI 1.72-24.31) and endometrium (SIR 6.86, 95% CI 2.23-16.02) in women and thyroid (SIR 23.33, 95% CI 9.38-48.08) and brain (SIR 9.80, 95% CI 3.18-22.88) in both sexes were tumor sites with significantly higher risks in DM1. There were differences in gene expression between healthy controls and patients with DM1 and between men and women with DM1; all patients with DM1 combined and female patients with DM1 displayed significant downregulation of the microRNA (miRNA)-200c/141 tumor suppressor family. CONCLUSIONS: Oncologic risk is increased in DM1, especially in women and for gynecologic, brain, and thyroid cancer. Expression of the miRNA-200/miRNA-141 tumor suppressor family is decreased in women with DM1.


Assuntos
Predisposição Genética para Doença , MicroRNAs/metabolismo , Distrofia Miotônica/epidemiologia , Neoplasias/epidemiologia , Adulto , Western Blotting , Regulação para Baixo , Feminino , Seguimentos , Perfilação da Expressão Gênica , Técnicas de Genotipagem , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/complicações , Distrofia Miotônica/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Estudos Retrospectivos , Risco , Fatores Sexuais
10.
J Mol Model ; 22(8): 181, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27417312

RESUMO

Bioethanol is one of the world's most extensively produced biofuels. However, it is difficult to purify due to the formation of the ethanol-water azeotrope. Knowledge of the azeotrope structure at the molecular level can help to improve existing purification methods. In order to achieve a better understanding of this azeotrope structure, the characterization of (ethanol)5-water heterohexamers was carried out by analyzing the results of electronic structure calculations performed at the B3LYP/6-31+G(d) level. Hexamerization energies were found to range between -36.8 and -25.8 kcal/mol. Topological analysis of the electron density confirmed the existence of primary (OH…O) hydrogen bonds (HBs), secondary (CH…O) HBs, and H…H interactions in these clusters. Comparison with three different solvated alcohol systems featuring the same types of atom-atom interactions permitted the following order of stability to be determined: (methanol)5-water > (methanol)6 > (ethanol)5-water > (ethanol)6. These findings, together with accompanying geometric and spectroscopic analyses, show that similar cooperative effects exist among the primary HBs for structures with the same arrangement of primary HBs, regardless of the nature of the molecules involved. This result provides an indication that the molecular ratio can be considered to determine the unusual behavior of the ethanol-water system. The investigation also highlights the presence of several types of weak interaction in addition to primary HBs. Graphical Abstract Water-ethanol clusters exhibit a variety of interaction types between their atoms, such as primary OH...O (blue), secondary CH...O (green) and H...H (yellow) interactions as revealed by Quantum Chemical Topology.

11.
J Phys Chem A ; 119(51): 12756-66, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26618667

RESUMO

The effect of sodium on the thermodynamics and kinetics of carbon gasification with carbon dioxide was studied by using quantum chemistry methods. Specifically, in the density functional context, two exchange-correlation functionals were used: B3LYP and M06. Some results obtained by these exchange-correlation functionals were contrasted with those obtained by the CCSD(T) method. It was found that density functional theory gives similar conclusions with respect to the coupled-cluster method. As one important conclusion we can mention that the thermodynamics of carbon monoxide desorption is not favored by the sodium presence. However, the presence of this metal induces: (a) an easier formation of one semiquinone group, (b) the dissociation of carbon dioxide, and

12.
Rev. colomb. quím. (Bogotá) ; 38(1): 151-167, abr. 2009. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-636653

RESUMO

La teoría de funcionales de la densidad (DFT: B3LYP/6-31+G(d)) fue empleada para la optimización de agregados estables sobre la superficie de energía potencial de los heterotetrámeros (etanol)3-agua. Las energías de tetramerización pueden llegar a valores hasta de -21,00 kcal/mol. Esta energía no se puede obtener considerando solo contribuciones de interacciones entre dos moléculas del agregado, lo cual sugiere la presencia de efectos cooperativos globales (positivos). Tales efectos son reflejados en distancias menores de los puentes de hidrógeno y distancias menores oxígeno-oxígeno, lo mismo que en elongaciones mayores del enlace O-Hen la molécula dadora de protón con un corrimiento hacia el rojo mayor en los heterotetrámeros, comparado con los heterodímeros de etanol-agua y el dímero de etanol. La mayor cooperatividad fue observada en los cuatro puentes de hidrógeno dispuestos en el patrón geométrico cíclico más grande posible, actuando todas las moléculas como aceptoras y dadoras de protón simultáneamente. Un análisis similar al de la caracterización de heterotetrámeros de (etanol)3-agua se llevó a cabo para los heterotetrámeros (metanol)3-agua y tetrámeros de etanol y metanol. La comparación de estos valores mostró que existe una gran similitud entre todos los parámetros analizados para agregados con el mismo patrón geométrico.


Density Functional Theory (DFT: B3LYP/6-31 + G(d)) was used for the optimization of clusters on the potential energy surface of (ethanol)3-water heterotetramers. The tetramerization energies can reach values up to -21.00 kcal/ mol. This energy can not be obtained by just considering the contributions from interactions between two cluster molecules, which suggests of the presence of global cooperative effects (positive). These effects are reflected in smaller hydrogen bond distances and smaller oxygen-oxygen distances, as well as in greater elongations of the O-H proton donor bond with a stronger "red-shift" in the heterotetramers compared to the ethanol-water heterodimers and the ethanol dimer. The largest cooperativity effect was observed in the four hydrogen bonds arranged in the largest possible cyclic geometric pattern, where all the molecules act as proton acceptor and donor simultaneously. A similar analysis to the characterization of (ethanol)3-water heterotetramers was carried out on (methanol)3-water heterotetramers, and ethanol and methanol tetramers, whose comparison showed a great similarity between all evaluated parameters for the clusters with equal geometric pattern.


A teoria de funcionais de densidade (DFT: B3LYP/6-31+G(d)) foi empregada para a otimização de agregados sobre a superfície de energia potencial dos heterotetrâmeros (etanol)3-água. As energias de tetramerização podem alcançar valores de até -21.00 kcal/mol. Esta energia não pode ser obtida por apenas considerando as contribuições das interações entre agregados de duas moléculas, o que sugere a presença global dos cooperativos efeitos (positivos). Tais efeitos são refletidos em menores comprimentos das pontes de hidrogênio e distâncias oxigênio-oxigênio, e também em maiores alongamentos da ligação O-H na molécula doadora de prótons, com um maior "red-shift" associado nos heterotetrâmeros do que nos heterodímeros de etanol-água e no dímero de etanol. A mais alta cooperatividade foi observada com as quatro pontes de hidrogênio dispostas no maior padrão geométrico cíclico possível, atuando simultaneamente todas as moléculas como aceptoras e doadoras de prótons. Uma análise similar ao da caracterização de heterotetrâmeros de (eta-nol)3-água se levou a cabo sobre heterotetrâmeros de (metanol)3-água e metanol, cuja comparação mostrou uma grande similaridade entre todos os parâmetros analisados para agregados com igual padrão geométrico.

13.
Biol Psychiatry ; 63(10): 946-52, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17950702

RESUMO

BACKGROUND: There is an increasing interest in the clinico-pathological correlation of mutations in progranulin (PGRN) and frontotemporal lobar degeneration (FTLD) complex diseases. We aim to study the PGRN expression variability in patients with different clinical features for a better understanding of its roles in FTLD disease. METHODS: We sequenced the PGRN gene in 72 patients suffering from FTLD (25 familial and 47 sporadic cases) and in 24 asymptomatic at-risk relatives. We also analyzed PGRN expression in blood by quantitative real-time polymerase chain reaction from 37 patients, 8 asymptomatic mutation carriers, and 10 control subjects as well as in brain tissue from 16 patients and 9 control subjects. RESULTS: Four novel mutations were associated with familial and sporadic FTLD and familial dementia associated with amyotrophic lateral sclerosis. We identified a close association between the IVS6-1G>A mutation in PGRN and corticobasal syndrome. Brain tissue was available for carriers of two of the four mutations (IVS6-1 G>A and P357HfsX3). Immunohistochemical analysis revealed ubiquitin- and TDP-43positive and tau/alpha-synuclein negative immunoreactive neuronal intranuclear inclusions. The relative expression of PGRN in the clinical sample was significantly lower in carriers of the IVS6-1 G>A than in control subjects. CONCLUSIONS: Progranulopathies are a major cause of the main phenotypes included in the FTLD complex. According to our results, the level of expression of PGRN in blood could be a useful marker both for diagnostics of part of the spectrum of FTLD conditions and for monitoring future treatments that might boost the level of PGRN in this disorder.


Assuntos
Demência/genética , Expressão Gênica/fisiologia , Predisposição Genética para Doença , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação/genética , RNA/metabolismo , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Proteínas de Ligação a DNA/metabolismo , Demência/metabolismo , Demência/patologia , Feminino , Humanos , Corpos de Inclusão Intranuclear/patologia , Masculino , Testes Neuropsicológicos , Progranulinas , Estudos Retrospectivos , Análise de Sequência , Ubiquitina/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/genética
14.
J Phys Chem A ; 111(33): 8250-6, 2007 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-17665885

RESUMO

The potential energy surface of the (ethanol)2-water heterotrimers for the trans and gauche conformers of ethanol was studied using density functional theory. The same approximation was used for characterizing representative clusters of (ethanol)3, (methanol)3, and (methanol)2-water. Trimerization energies and enthalpies as well as the analysis of geometric parameters suggest that the structures with a cyclic pattern in the three hydrogen bonds of the type O-H---O (primary hydrogen bonds), where all molecules are proton donor-acceptor at the same time, are more stable than those with just two primary hydrogen bonds. Additionally, we propose the formation of "secondary hydrogen bonds" between hydrogen atoms of the methyl group of ethanol and the oxygen atom of water or other ethanol molecule (C-H---O), which were found to be weaker than the primary hydrogen bonds.


Assuntos
Etanol/química , Polímeros/química , Água/química , Modelos Moleculares
15.
Rev. colomb. anestesiol ; 34(3): 171-176, jul.-sept. 2006. tab
Artigo em Espanhol | LILACS | ID: lil-456276

RESUMO

A partir de 1930 se ha trabajado en el desarrollo de técnicas de aislamiento pulmonar, generando una importante evolución en la anestesia, principalmente en el campo de anestesia cardiotorácica, al mejorar el conocimiento en la fisiología pulmonar, con el resultado de intervenciones que implican aislamiento pulmonar cada vez mejor. El objetivo de la separación o aislamiento pulmonar es la interrupción selectiva de la ventilación en un pulmón (colapso pulmonar total) o un segmento del pulmón (colapso selectivo lobar). A medida que las indicaciones clínicas para el aislamiento pulmonar se han expandido, han surgido limitaciones para el uso de los tubos de doble luz; por ésto, han tomado importancia otras alternativas para el aislamiento pulmonar, como los bloqueadores bronquiales. En la actualidad, a pesar de disponer de tantos dispositivos, no hay estudios aleatoriazados que demuestren la superioridad de uno sobre otro...


Assuntos
Ventilação Pulmonar , Ventilação , Tubulações
16.
Rev. méd. domin ; 45(1): 10-3, ene.-mar. 1985. tab
Artigo em Espanhol | LILACS | ID: lil-35082

RESUMO

El presente estudio se realizó en la comunidad de Sabaneta, provincia de San Juan de la Maguana. Con el objetivo de conocer cuales eran las causas principales por lo cual enferman sus habitantes. Utilizando como metodología el método aleatorio simple para la muestra. La encuesta y la observación participante como técnica. Encontrándose que las causas principales son políticas, económicas y sociales


Assuntos
Humanos , Masculino , Feminino , Morbidade , Inquéritos Epidemiológicos , Fatores Socioeconômicos , República Dominicana
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