Thermochemical study of 1-acetyl vinyl p-nitrobenzoate: vinyl bond enthalpy in captodative olefins.

Captodative olefins are highly reactive and selective substrates in Diels-Alder and 1,3-dipolar cycloadditions. Seeking an explanation of this fact based on molecular energetics, the thermochemical analysis of 1-acetyl vinyl p-nitrobenzoate, a captodative olefin, has been performed using semi-micro-combustion calorimetry, effusion measurements through a quartz crystal microbalance, and differential scanning calorimetry. The molar standard combustion energy and enthalpy as well as the molar standard formation enthalpy are reported along with sublimation and melting enthalpies. From these data, experimental formation enthalpy of the gas-phase is derived and compared with the theoretical value calculated through the density functional theory procedure. The olefinic bond enthalpy is also computed from experimental data, and the relevance of the results is discussed.

Tratamento endovascular das doenças da aorta torácica: análise dos resultados de um centro / Endovascular treatment of thoracic aortic diseases: a single center result analysis

OBJETIVO: Analisar os resultados do tratamento de uma série consecutiva de pacientes submetidos a tratamento endovascular de doenças da aorta torácica. Foram observados o sucesso técnico, o sucesso terapêutico, a morbimortalidade e a taxa de complicações perioperatórias e de reintervenções. MATERIAIS E MÉTODOS: Estudo retrospectivo, realizado em um centro de referência, no período de janeiro de 2010 a julho de 2011, em que foram analisados pacientes submetidos a correção endovascular de doenças da aorta torácica. A população foi dividida em dois grupos: grupo 1 (G1) - aneurismas de aorta torácica verdadeiros, úlcera aórtica e pseudoaneurisma; grupo 2 (G2) - dissecção aórtica tipo B crônica. RESULTADOS: Em um total de 55 pacientes tratados, 29 pertenciam ao G1 e 26, ao G2. As idades médias foram 66,8 ± 10 e 56,4 ± 7 anos, respectivamente. Os sucessos técnico e terapêutico foram, respectivamente, 86,3% e 68,6% no G1 e 100% e 74% no G2. A mortalidade perioperatória foi 10,3% no G1 e 7,6% no G2, com taxa de mortalidade anual de 10,3% no G1 e de 19,3% no G2. As taxas de reintervenções foram 10,3% e 15,3%, respectivamente. CONCLUSÃO: Em nosso estudo, o tratamento endovascular das doenças da aorta torácica demonstrou ser um método viável e associado a aceitáveis taxas de complicações.

OBJECTIVE: To analyze treatment outcomes in a consecutive series of patients submitted to endovascular treatment of thoracic aortic disease. Technical success, therapeutic success, morbimortality, rate of perioperative complications and reinterventions were taken into consideration. MATERIALS AND METHODS: The present retrospective study was developed in a reference center in the period from January 2010 to July 2011, involving patients submitted to endovascular treatment of thoracic aortic disease. The study population was divided into two groups: group 1 (G1) - true thoracic aortic aneurysms, aortic ulcer and pseudoaneurysm; group 2 (G2) - chronic type B aortic dissection. RESULTS: Out of a total of 55 patients, 29 belonged to the G1 and 26 to the G2 group. Mean ages were 66.8 ± 10 and 56.4 ± 7 years, respectively. The technical and therapeutic success reached respectively 86.3% and 68.6% in G1 and 100% and 74% in G2. The perioperative mortality rate was 10.3% in G1 and 19.3% in G2. The reintervention rate was 10.3% in G1 and 15.3% in G2. CONCLUSION: In the present study, the endovascular treatment of thoracic aortic disease proved to be a feasible method associated with acceptable rate of complications.

Assessing the temporal course of neointimal hyperplasia formation after different generations of drug-eluting stents.

OBJECTIVES: This study sought to assess the temporal course of neointimal hyperplasia (NIH) formation following implantation of 2 different generations of drug-eluting stents (DES). BACKGROUND: The amount of NIH following DES implantation correlates with the potency of the antiproliferative drug, its kinetic release, as well as some individual characteristics, as the presence of diabetes mellitus (DM). Recently, some publications have suggested a continuous growth of NIH following DES, which in some cases, might result in late "catch-up." METHODS: Twenty-five patients with single, de novo lesions were treated with sirolimus-eluting stents (SES) (n = 12) and biolimus-eluting stents (BES) (n = 13) and underwent intravascular ultrasound evaluation immediately after the procedure and at 9-month and 5-year follow-ups. The primary endpoint was the comparison of the percentage of NIH obstruction between mid- and long-term follow-up. RESULTS: Mean age was 59 years and 28% of patients had DM. Overall, the percentage of NIH obstruction significantly increased from 9 months to 5 years (1.3% at first follow-up vs. 4.8% at second follow-up, p = 0.002). There was no significant difference in the variation of vessel volume (Δ = -0.70 mm(3)/mm BES vs. Δ = 0.18 mm(3)/mm SES, p = 0.56), lumen volume (Δ = 0.40 mm(3)/mm BES vs. Δ = -0.05 mm(3)/mm SES, p = 0.71), and percentage of NIH obstruction (Δ = 3.0% BES vs. Δ = 3.8% SES, p = 0.55) among DES. However, diabetic patients had a marked NIH increase along the years (NIH volume at second follow-up: 10.15 mm(3) DM vs. 5.11 mm(3) non-DM, p = 0.028). CONCLUSIONS: The present serial intravascular ultrasound assessment supports the occurrence of continuous NIH growth following different generations of DES. These findings seem to be particularly more pronounced among patients with DM.

Atresia congênita do tronco da coronária esquerda em adulto jovem: rasa e potencialmente fatal anomalia coronária / Congenital atresia of the left main coronary artery in a young adult: a rare and potentially fatal coronary anomaly

Relato do caso de paciente do sexo masculino, 35 anos de idade, com atresia congênita do tronco da artéria coronária esquerda, afecção extremamente rara e com poucos casos descritos na literatura. Nessa afecção, o óstio da coronária esquerda está ausente, o tronco da coronária esquerda termina em fundo cego e o fluxo sanguíneo se dá da coronária direita para a esquerda por pequenas artérias colaterais e retrogradamente. O diagnóstico diferencial envolve outras malformações congênitas (artéria coronária direita única e origem anômala da artéria coronária esquerda do tronco da artéria pulmonar) e doença aterosclerótica adquirida do tronco da coronária esquerda.

We report the case of a 35-year-old male patient with congenital atresia of the left main coronary artery, a raredisease with few cases reported in the literature. In this anomaly, the left coronary ostium is absent, the proximalleft main trunk ends blindly and blood flow is retrograde from the right to the left coronary artery by small collateralarteries. Differential diagnosis includes other congenital malformations (single right coronary artery and anomalousorigin of the left coronary artery from the pulmonary artery) and acquired atherosclerotic disease of the left main coronary artery.

Assessing the temporal course of neointimal hyperplasia formation after different generations of drug-eluting stents

Objectives This study sought to assess the temporal course of neointimal hyperplasia (NIH) formationfollowing implantation of 2 different generations of drug-eluting stents (DES).Background The amount of NIH following DES implantation correlates with the potency of the antiproliferativedrug, its kinetic release, as well as some individual characteristics, as the presence ofdiabetes mellitus (DM). Recently, some publications have suggested a continuous growth of NIH followingDES, which in some cases, might result in late “catch-up.”Methods Twenty-five patients with single, de novo lesions were treated with sirolimus-elutingstents (SES) (n 12) and biolimus-eluting stents (BES) (n 13) and underwent intravascular ultrasoundevaluation immediately after the procedure and at 9-month and 5-year follow-ups. The primaryendpoint was the comparison of the percentage of NIH obstruction between mid- and longtermfollow-up.Results Mean age was 59 years and 28% of patients had DM. Overall, the percentage of NIH obstructionsignificantly increased from 9 months to 5 years (1.3% at first follow-up vs. 4.8% at secondfollow-up, p 0.002). There was no significant difference in the variation of vessel volume (Ä 0.70 mm3/mm BES vs. Ä 0.18 mm3/mm SES, p 0.56), lumen volume (Ä 0.40 mm3/mm BESvs. Ä 0.05 mm3/mm SES, p 0.71), and percentage of NIH obstruction (Ä 3.0% BES vs. Ä 3.8% SES, p 0.55) among DES. However, diabetic patients had a marked NIH increase along theyears (NIH volume at second follow-up: 10.15 mm3 DM vs. 5.11 mm3 non-DM, p 0.028).Conclusions The present serial intravascular ultrasound assessment supports the occurrence of continuousNIH growth following different generations of DES. These findings seem to be particularlymore pronounced among patients with DM.

La configuración del campo de la rectoría escolar oficial en Colombia / A Configuraçao do campo da reitoria escolar oficial na Colômbia / The configuration of the official school principalship in Colombia

Este artículo se inscribe en el contexto de las reformas educativas contemporáneas y caracteriza cómo se está configurando el campo de la rectoría oficial escolar en Colombia a partir de las relaciones de poder que se generan entre el rector o rectora y las dimensiones macropolítica y micropolítica de las instituciones educativas. Los resultados muestran cómo el campo de la rectoría está fuertemente regulado por las normas y políticas educativas nacionales y la recontextualización que se hace de éstas en los escenarios macropolíticos locales. El campo del rector o rectora se configura a través de tres líneas de fuerza de dominio que cambian la orientación de la rectoría, afectan su función y generan cambios en sus relaciones: la primera hala al rector o rectora hacia el entorno en búsqueda de recursos, proyectos y relaciones con el gobierno local; la segunda hala al rector o rectora hacia la promoción de la democratización de la institución educativa y el disciplinamiento de los maestros y maestras; la tercera se orienta hacia la rendición de cuentas. Concluimos que la reconfiguración del campo del rector o rectora se da en un contexto socialmente problematizado y signado por amplias expectativas sobre el papel de la escuela y los rectores y rectoras. La labor directiva está marcada por un sesgo altamente administrativo, una orientación hacia el disciplinamiento de los maestros y maestras, y la rendición de cuentas. En medio de restricciones, los rectores y rectoras ensayan estrategias de negociación, y promueven acciones para lograr cumplir con los objetivos institucionales, con las demandas de la comunidad escolar y con las expectativas de su rol.

Este artigo fica no contexto das reformas educativas contemporâneas e caracteriza como se configura o campo da reitoria oficial escolar na Colômbia a partir das relações de poder que se geram entre o reitor e as dimensões macropolítica e micropolítica das instituições educativas. Os resultados indicam como o campo da reitoria está regulado fortemente pelas normas, políticas educativas nacionais e pela sua re-contextualização nos cenários macropoliticos locais. O campo do reitor configura-se através de três linhas de força de domínio que alteram a orientação da reitoria, afetam sua função e geram mudanças nas suas relações. A primeira impulsiona o reitor para o meio na busca de recursos, projetos e relações como o governo local; a segunda impulsiona o reitor para a promoção da democratização da instituição educativa e para o disciplinamento dos professores e das professoras; a terceira orienta-se para a apresentação de relatórios. O artigo conclui que a reconfiguração do campo do reitor se apresenta num contexto socialmente problematizado e caracterizado por expectativas amplas sobre o papel da escola e dos reitores e reitoras. A função diretiva está marcada por um preconceito altamente administrativo, uma orientação para o disciplinamento dos professores e das professoras, como também para a apresentação de relatórios. No meio de restrições, os reitores e as reitoras ensaiam estratégias de negociação e promovem ações para satisfazer os objetivos institucionais, as demandas da comunidade escolar e as expectativas do seu papel.

This article belongs in the context of contemporary school reforms and characterizes how the Colombian school principalship is being configured from the power relations generated between the principal and the macropolitical and micropolitical dimensions in educational institutions. The results show how the field of principalship is heavily regulated by national educational norms and policies and by their corresponding recontextualization in the local macropolitical scenarios. The principalship field is configured through three domain force lines that change the principalship orientation, affect its function and generate changes in their relations. The first force induces the principal towards the search for resources, projects and their relations; the second induces the principal towards the promotion of the democratization of the educational institution and to disciplining both male and females teachers; and the third refers to reporting management activities. The conclusion states that the reconfiguration of the principal's field takes place in context that is socially problematized and marked by wide expectations about the role of schools and by both male and female principals. The directive function is widely marked by a highly administrative bias, an orientation towards the disciplining of teachers and towards the reporting of management activities. In a world of restrictions, the principals try new negotiation strategies and promote actions aiming at meeting institutional objectives, along with the demands from the school and the expectations resulting from their roles.