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1.
J Chem Phys ; 158(14): 144118, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37061506

RESUMO

The positions of grid points for representing a multidimensional potential energy surface (PES) have a non-negligible impact on its accuracy and the associated computational effort for its generation. Six different positioning schemes were studied for PESs represented by n-mode expansions as needed for the accurate calculation of anharmonic vibrational frequencies by means of vibrational configuration interaction theory. A static approach, which has successfully been used in many applications, and five adaptive schemes based on Gaussian process regression have been investigated with respect to the number of necessary grid points and the accuracy of the fundamental modes for a small set of test molecules. A comparison with a related, more sophisticated, and consistent approach by Christiansen et al. is provided. The impact of the positions of the ab initio grid points is discussed for multilevel PESs, for which the computational effort of the individual electronic structure calculations decreases for increasing orders of the n-mode expansion. As a result of that, the ultimate goal is not the maximal reduction of grid points but rather the computational cost, which is not directly related.

4.
J Chem Theory Comput ; 17(9): 5955-5967, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34378918

RESUMO

Geometry optimization based on Gaussian process regression (GPR) was extended to internal coordinates. We used delocalized internal coordinates composed of distances and several types of angles and compared two methods of including them. In both cases, the GPR surrogate surface is trained on geometries in internal coordinates. In one case, it predicts the gradient in Cartesian coordinates and in the other, in internal coordinates. We tested both methods on a set of 30 small molecules and one larger Rh complex taken from the study of a catalytic mechanism. The former method is slightly more efficient, while the latter method is somewhat more robust. Both methods reduce the number of required optimization steps compared to GPR in Cartesian coordinates or the standard L-BFGS optimizer. We found it advantageous to use automatically adjusted hyperparameters to optimize them.

5.
Int. j. cardiovasc. sci. (Impr.) ; 34(4): 452-458, July-Aug. 2021. tab
Artigo em Inglês | LILACS, CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1286838

RESUMO

BACKGROUND: Maternal mortality rates in Brazil remain above the goals established by the United Nations Sustainable Development Goals. Heart disease is estimated to affect 4% of all pregnancies and remains by itself the main indirect obstetric cause of maternal death. In the last decades, a significant improvement in the prognosis of heart diseases has made pregnancy possible in women with heart disease and provided better maternal and fetal outcomes. OBJECTIVES: To establish a multicenter Brazilian Registry of pregnant women with heart disease; to study the causes of immediate and late maternal mortality; and to assess the prevalence of heart disease in the country's macro-regions. METHODS: This is an observational study, with retrospective and prospective stages, of the clinical and obstetric progression of pregnant women with heart disease. These women consecutively received care during pregnancy and will be followed up for up to a year after delivery at public and private hospitals with infrastructure for the execution of this project, a principal investigator, and approval by Ethics and Research Committees. RESULTS: Our results will be presented after data collection and statistical analysis, aiming to demonstrate immediate and late maternal mortality rates, as well as the prevalence of heart disease in the country and its cardiovascular and obstetric complications during pregnancy. CONCLUSIONS: REBECGA will be the Brazilian Registry of heart disease and pregnancy and it will contribute to planning preventive measures, raising financial resources for the improvement of high-risk prenatal care, and reducing immediate and late maternal mortality due to heart disease.


Assuntos
Humanos , Feminino , Gravidez , Complicações Cardiovasculares na Gravidez/epidemiologia , Sistema de Registros , Mortalidade Materna , Complicações Cardiovasculares na Gravidez/prevenção & controle , Estudos Transversais , Estudos Prospectivos , Estudos Retrospectivos , Estudos Longitudinais , Cardiopatias/epidemiologia , Métodos
6.
J Phys Chem A ; 124(41): 8633-8642, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32946231

RESUMO

Atom probe tomography allows us to measure the three-dimensional composition of materials with up to atomic resolution by evaporating the material using high electric fields. Initially developed for metals, it is increasingly used for covalently bound structures. To aid the interpretation of the obtained fragmentation pattern, we modeled the fragmentation and desorption of self-assembled monolayers of thiolate molecules on a gold surface in strong electrostatic fields using density functional theory. We used a cluster model and a periodic model of amino-undecanethiolate, NH2(CH2)11S, and fluoro-decanethiolate, CF3(CF2)7(CH2)2S. In the former molecule, the fragment CH2NH2+ was found to evaporate at fields of 5.4-7.7 V/nm. It was followed by different hydrocarbon fragments. Fluoro-decanethiolate evaporates CF3+ at fields of 5.7-6.7 V/nm in the cluster model and at 15.4-23.1 V/nm in the periodic model, followed by CF2+ and C2F42+. Detailed analysis of the electronic structure during the evaporation process revealed a stepwise accumulation of the charge in the head groups exposed to the strongest fields, followed by dissociation of covalent bonds. These observations will facilitate the analysis of atom probe experiments of covalently bound structures.

7.
Arq Bras Cardiol ; 114(5): 849-942, 2020 06 01.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32491078
9.
Eur Heart J Cardiovasc Imaging ; 18(1): 54-61, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26928981

RESUMO

AIMS: We sought to present a series of 13 pregnancy-associated spontaneous coronary artery dissection (P-SCAD), their angiographic and multimodal imaging findings, acute phase treatment, and outcomes. METHODS AND RESULTS: Between 2005 and 2015, 13 cases of P-SCAD were collected from a database of 11 tertiary hospitals. The mean age was 33.8 ± 3.7 years; most patients had no risk factors for coronary artery disease, and the majority were multiparous. P-SCAD occurred during the puerperium in 12 patients with a median time of 10 days. Only one patient presented with P-SCAD in the 37th week of pregnancy, and she was the only patient who died in this series. Six patients (46%) presented with ST-segment elevation acute myocardial infarction (STEMI), six (46%) presented with non-STEMI, and one presented with unstable angina; one-third of women had cardiogenic shock. In 12 patients, the dissection involved the left anterior descending or circumflex artery, and it extended to the left main coronary artery in 6 patients. Intravascular ultrasound or optical coherence tomography helped to confirm diagnosis and guide treatment in 46% of cases. Seven women were managed clinically; percutaneous coronary intervention was performed in five cases, and coronary artery bypass grafting was performed in one patient. CONCLUSION: In these 13 cases of P-SCAD, clinical presentation commonly included acute myocardial infarction and cardiogenic shock. Multivessel dissections and involvement of the left coronary artery and left main coronary artery were highly prevalent. Clinicians must be aware of angiographic appearances of P-SCAD for prompt diagnosis and management in these high-risk patients.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Anomalias dos Vasos Coronários/terapia , Imagem Multimodal/métodos , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Resultado da Gravidez , Doenças Vasculares/congênito , Adulto , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Anomalias dos Vasos Coronários/mortalidade , Bases de Dados Factuais , Feminino , Seguimentos , Idade Gestacional , Mortalidade Hospitalar , Humanos , Intervenção Coronária Percutânea/métodos , Intervenção Coronária Percutânea/mortalidade , Período Pós-Parto , Gravidez , Complicações Cardiovasculares na Gravidez/terapia , Estudos Retrospectivos , Medição de Risco , Amostragem , Centros de Atenção Terciária , Ultrassonografia de Intervenção/métodos , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/mortalidade , Doenças Vasculares/terapia
10.
Eur Heart J Cardiovasc Imaging ; 18(1): 54-61, 2017. ilus, tab
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1062603

RESUMO

AIMS: We sought to present a series of 13 pregnancy-associated spontaneous coronary artery dissection (P-SCAD), their angiographic and multimodal imaging findings, acute phase treatment, and outcomes. METHODS AND RESULTS: Between 2005 and 2015, 13 cases of P-SCAD were collected from a database of 11 tertiary hospitals. The mean age was 33.8 ± 3.7 years; most patients had no risk factors for coronary artery disease, and the majority were multiparous. P-SCAD occurred during the puerperium in 12 patients with a median time of 10 days. Only one patient presented with P-SCAD in the 37th week of pregnancy, and she was the only patient who died in this series. Six patients (46%) presented with ST-segment elevation acute myocardial infarction (STEMI), six (46%) presented with non-STEMI, and one presented with unstable angina; one-third of women had cardiogenic shock. In 12 patients, the dissection involved the left anterior descending or circumflex artery, and it extended to the left main coronary artery in 6 patients. Intravascular ultrasound or optical coherence tomography helped to confirm diagnosis and guide treatment in 46% of cases. Seven women were managed clinically; percutaneous coronary intervention was performed in five cases, and coronary artery bypass grafting was performed in one patient...


Assuntos
Dissecação da Artéria Carótida Interna , Infarto do Miocárdio , Ultrassonografia de Intervenção
11.
PLoS One ; 10(12): e0144385, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26650684

RESUMO

BACKGROUND: To evaluate maternal heart disease as a cause or complicating factor for severe morbidity in the setting of the Brazilian Network for Surveillance of Severe Maternal Morbidity. METHODS AND FINDINGS: Secondary data analysis of this multicenter cross-sectional study was implemented in 27 referral obstetric units in Brazil. From July 2009 to June 2010, a prospective surveillance was conducted among all delivery hospitalizations to identify cases of severe maternal morbidity (SMM), including Potentially Life-Threatening Conditions (PLTC) and Maternal Near Miss (MNM), using the new criteria established by the WHO. The variables studied included: sociodemographic characteristics, clinical and obstetric history of the women; perinatal outcome and the occurrence of maternal outcomes (PLTC, MNM, MD) between groups of cardiac and non-cardiac patients. Only heart conditions with hemodynamic impact characterizing severity of maternal morbidity were considered. 9555 women were included in the Network with severe pregnancy-related complications: 770 maternal near miss cases and 140 maternal death cases. A total of 293 (3.6%) cases were related to heart disease and the condition was known before pregnancy in 82.6% of cases. Maternal near miss occurred in 15% of cardiac disease patients (most due to clinical-surgical causes, p<0.001) and 7.7% of non-cardiac patients (hemorrhagic and hypertensive causes, p<0.001). Maternal death occurred in 4.8% of cardiac patients and in 1.2% of non-cardiac patients, respectively. CONCLUSIONS: In this study, heart disease was significantly associated with a higher occurrence of severe maternal outcomes, including maternal death and maternal near miss, among women presenting with any severe maternal morbidity.


Assuntos
Cardiopatias/epidemiologia , Cardiopatias/mortalidade , Mortalidade Materna/tendências , Morbidade/tendências , Complicações na Gravidez/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Criança , Estudos Transversais , Feminino , Cardiopatias/complicações , Cardiopatias/fisiopatologia , Humanos , Pessoa de Meia-Idade , Gravidez , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida , Adulto Jovem
12.
Rev. bras. hipertens ; 19(4): 95-98, out.-dez.2012.
Artigo em Português | LILACS | ID: biblio-881717

RESUMO

As controvérsias sobre os padrões pressóricos durante a gravidez normal justificam a realização de estudos para melhor entender a questão. O objetivo deste estudo foi conhecer as variações normais da pressão arterial (PA), através da monitorização ambulatorial da pressão arterial (MAPA), em gestantes saudáveis numa capital da região norte do Brasil. Foram estudadas 89 gestantes normotensas, nulíparas ou multíparas, de 3 centros obstétricos da cidade de Belém (PA). As gestantes foram divididas em três grupos, segundo a idade gestacional: Grupo 1, composto por 25 grávidas, entre 6 e 13 semanas de gestação; Grupo 2, por 32 grávidas, entre 14 e 25 semanas; e Grupo 3, por 32 grávidas, entre 28 e 38 semanas de gestação. As 89 gestantes apresentavam idade entre 18 e 35 anos (mediana de 24 anos). Não houve diferenças significantes entre o número de nulíparas e multíparas (p = 0,5555). Quanto às variáveis da MAPA analisadas (média de 24 horas) houve diferenças estatisticamente significantes apenas em três delas: PA sistólica no Grupo 3 (aumento), PA diastólica no Grupo 2 (redução) e descenso noturno diastólico no Grupo 1 (aumento). Podemos concluir que em grávidas normotensas, os parâmetros da MAPA avaliados tiveram comportamento similar aos padrões de normalidade considerados para a população geral.


Controversies regarding blood pressure patterns during normal pregnancy justify studies for their better understanding. The objective of this study was to verify normal blood pressure (BP) variations by means of ambulatory blood pressure monitoring (ABPM) in healthy pregnant women in the capital of a northern Brazilian state. A total of 89 normotensive nulliparous or multiparous pregnant women from 3 obstetric centers in the city of Belém ­ State of Pará, were studied. The pregnant women were divided into three groups, according to their gestational age: Group 1, comprising 25 pregnant women between 6 and 13 weeks of gestation; Group 2, with 32 pregnant women between 14 and 25 weeks of gestation; and Group 3, with 32 pregnant women between 28 and 38 weeks of gestation. The ages of the 89 pregnant women ranged from 18 to 35 years (median of 24,0 years). There was no significant difference between the number of nulliparae and multiparae (p = 0.5555). As regards the ABPM variables analyzed (mean of 24 hours), statistically significant differences were observed in only three of them: systolic BP in Group 3 (increase); diastolic BP in Group 2 (decrease), and diastolic nocturnal dip in Group 1 (increase). In conclusion, in normotensive pregnant women the variation of the ABPM parameters analyzed was similar to the normal patterns observed in the general population.


Assuntos
Humanos , Feminino , Gravidez , Adolescente , Adulto , Monitorização Ambulatorial da Pressão Arterial , Interpretação Estatística de Dados
13.
RELAMPA, Rev. Lat.-Am. Marcapasso Arritm ; 25(1): 5-12, jan.-mar. 2012. tab, ilus
Artigo em Português | LILACS, Sec. Est. Saúde SP | ID: lil-641343

RESUMO

Objetivo: Objetivou-se, neste estudo, avaliar as complicações maternas e fetais (clínicas e obstétricas) em mulheres portadoras de marca-passo cardíaco, assim como, a relação entre os modos de estimulação cardíaca(atrial, ventricular ou atrioventricular) e a evolução da gestação quanto às intercorrências materno-fetais, Peso de RN e APGAR. Materiais e métodos: Pesquisa retrospectiva embasada em análise de prontuários médicos de gestantes portadoras de marca-passo cardíaco, acompanhadas nos serviços de Cardiopatia e Gravidez do IDPC, INCOR e HSP (1980 a 2003). Resultado: Analisaram-se 65 gestações em 52 mulheres. 12 pacientes tiveram implante do marca-passo durante a gravidez. A mostra foi dividida em dois grupos, segundo o modo de estimulação cardíaca. Grupo 1:> 25 gestações no modo atrioventricular. Grupo 2: 40 gestações no modo ventricular. Os dois grupos foram semelhantes do ponto de vista estatístico. Não houve diferença significativa entre os modos de estimulação e o peso dos recém-nascidos (p=0,765), bem com em relação à nota de Apgar (p=0,287). Observamos correlação negativa significante (p=0.017) entre o tempo decorrido entre o implante do marca-passo e a gestação, com o peso dos recém-nascidos. Conclusão: Concluiu-se que, em ambos os modos de estimualaçao cardíaca houve recém-nascidos com boas condições de nascimento e com peso adequado para a idade gestacional. Quanto maior o tempo decorrido entre o implante de marca-passo e a gestacional, menor foi o peso dos recém-nascidos.


Assuntos
Humanos , Feminino , Gravidez , Marca-Passo Artificial , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Estudos Retrospectivos
14.
In. Anon. Livro-texto da Sociedade Brasileira de Cardiologia. Barueri, SP, Manole, 2012. p.1464-1474, tab.
Monografia em Português | LILACS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1081216
15.
Arq. bras. cardiol ; 93(6,supl.1): e130-e132, dez. 2009.
Artigo em Português | LILACS | ID: lil-554222
16.
Arq Bras Cardiol ; 90(5): e33-5, 2008 May.
Artigo em Inglês, Português | MEDLINE | ID: mdl-18516392

RESUMO

We describe here the pregnancy follow-up and outcome in a patient with Takayasu's arteritis, with a detailed account of the complications during gestation and delivery and the impact of the disease on the newborn's health.


Assuntos
Complicações Cardiovasculares na Gravidez/diagnóstico , Arterite de Takayasu/diagnóstico , Adolescente , Cesárea , Feminino , Humanos , Hipertensão/complicações , Recém-Nascido , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Resultado da Gravidez , Arterite de Takayasu/diagnóstico por imagem , Ultrassonografia Doppler
17.
Arq. bras. cardiol ; 90(5): e34-e36, maio 2008.
Artigo em Inglês, Português | LILACS | ID: lil-482932

RESUMO

No presente relato, que descreve a gestação de paciente portadora de arterite de Takayasu, serão avaliadas a interação dessa afecção com a gravidez e as intercorrências materno-fetais, do parto e do recém-nascido.


We describe here the pregnancy follow-up and outcome in a patient with Takayasu's arteritis, with a detailed account of the complications during gestation and delivery and the impact of the disease on the newborn's health.


Assuntos
Adolescente , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico , Arterite de Takayasu/diagnóstico , Cesárea , Hipertensão/complicações , Resultado da Gravidez , Complicações Cardiovasculares na Gravidez , Arterite de Takayasu , Ultrassonografia Doppler
18.
In. Serrano Jr, Carlos V; Timeramn, Ari; Stefanini, Edson. Tratado de Cardiologia SOCESP. São Paulo, Manole, 2 ed; 2009. p.1712-1722.
Monografia em Português | LILACS, Sec. Est. Saúde SP, SESSP-HMLMBACERVO, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1070413

RESUMO

O suporte avançado de vida (SAV) compreende dois princípos: 1) somente os profissionais da saúde devem aplicar as medidas necessárias, pois estas constituem um procedimento médico; 2) os profissionais responsáveis por tais medidas devem seguir condutas padronizadas e normatizadas que estejam de acordo com o ABCD secundário. A abordagem deste capítulo enfocoua ressuscitaçao cardiopulmonar (RCP) nas casuísticas de parada cardiorrespiratória (PCR) em suas diversas formas. A PCR apresenta três mecanismos fisiopatológicos: a) fibrlação ventricular ou taquicardia ventricular (FT/TV), b) assistolia, c) atividade elétrica sem pulso (AESP). Os procedimentos terapêuticos mais importantes aplicados na RCP em casuísticas de PCR são fundamentais no intervalo de tempo entre o colapso e o início do tratamento...


Assuntos
Adulto , Suporte Vital Cardíaco Avançado
19.
In. Serrano Jr, Carlos V; Timeramn, Ari; Stefanini, Edson. Tratado de Cardiologia SOCESP. São Paulo, Manole, 2 ed; 2009. p.2456-2472, ilus.
Monografia em Português | LILACS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1070419

RESUMO

A mortalidade no ciclo gravídico-puerperal pode ser por causa direta ou indireta. As causas diretas ou obstétricas são as mais comuns e poderiam ser evitadas pela melhor qualidade de assistência médica durante o ciclo, uma vez que são decorrentes de inadequação do atendimento, má prática médica e negligência da paciente. Entre as causas indiretas, ou seja, a morte materna decorrente de doença orgânica subjacente, destacam-se, por importância, as cardiopatias, admitindo-se que podem ser evitadas por meio de assistência pré-natal especializada e adequado planejamento familiar.


Assuntos
Anticoncepção , Cardiopatias , Gravidez
20.
Arq Bras Cardiol ; 84(4): 340-2, 2005 Apr.
Artigo em Português | MEDLINE | ID: mdl-15880210

RESUMO

The patient was a male with myasthenia gravis, hospitalized with acute respiratory failure due to decompensation of the underlying disease. He evolved with findings suggestive of acute myocardial infarction, with electrocardiographic and enzymatic alterations compatible with that diagnosis. The patient underwent emergency coronary angiography, which showed no severe coronary obstruction, although his left ventricle had significant systolic dysfunction with characteristic alterations, on ventriculography, of the syndrome described as transient ventricular dysfunction or Takotsubo syndrome. On evolution, complete recovery of the electrocardiographic alterations and systolic ventricular function assessed on echocardiography occurred, confirming the syndrome.


Assuntos
Cardiomiopatias/diagnóstico , Infarto do Miocárdio/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Angiografia Coronária , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome
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