Síntese de tetrahidroquinolinas a partir da D-eritrose

Dissertação de mestrado em Química Medicinal

Relatório de atividade profissional

Relatório de atividade profissional de mestrado em Ciências - Formação Contínua de Professores (área de especialização em Biologia e Geologia)

Echocardiographic Assessment of the Pulmonary Venous Flow: An Indicator of Increased Pulmonary Flow in Congenital Cardiac Malformations

OBJECTIVE: To identify the left inferior pulmonary vein as an indirect marker of increased pulmonary flow in congenital heart diseases.METHODS: We carried out a prospective consecutive study on 40 patients divided into 2 groups as follows: G1 - 20 patients diagnosed with congenital heart disease and increased pulmonary flow; G2 (control group) - 20 patients who were either healthy or had congenital heart disease with decreased or normal pulmonary flow. We obtained the velocity-time integral of the left inferior pulmonary vein flow, excluding the "reverse A" wave, with pulsed Doppler echocardiography.RESULTS: In G1, 19 out of the 20 patients had well-identified dilation of the left inferior pulmonary vein. No G2 patient had dilation of the left inferior pulmonary vein. Dilation of the left inferior pulmonary vein in conditions of increased pulmonary flow had sensitivity of 95%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 95% (1 false-negative case). The integral of time and velocity of the pulmonary venous flow obtained with pulsed Doppler echocardiography was greater in the G1 patients (G1=25.0±4.6 cm versus G2=14.8±2.1 cm, p=0.0001).CONCLUSION: The identification of dilation of the left inferior pulmonary vein suggests the presence of congenital heart disease with increased pulmonary flow. This may be used as an indirect sign of increased flow, mainly in malformations of difficult diagnosis, such as atrial septal defects of the venous sinus or coronary sinus type.

Oficina de escrita criativa: como se conta uma história?

Projecto de mestrado em Mediação Cultural e Literária

Descodificação do De re aedificatoria de Alberti: gramáticas de forma para a análise e geração de edifícios sagrados

Teses de Doutoramento em Arquitectura.

Expressao genica associada ao estresse oxidativo no coracao de camundongo apos isquemia intestinal

FUNDAMENTO: O fenômeno da isquemia e reperfusão intestinal é um evento frequente na clínica e está associado a repercussões deletérias em órgãos a distância, em especial ao coração. OBJETIVO: Investigar a expressão gênica do estresse oxidativo e defesa antioxidante no coração de camundongos isogênicos, submetidos a isquemia e reperfusão intestinal (IR). MÉTODOS: Doze camundongos (C57BL/6) foram distribuídos em dois grupos: Grupo IR (GIR) com 60 min de oclusão da artéria mesentérica superior, seguidos de 60 min de reperfusão. Grupo Controle (GC) submetidos a anestesia e a laparotomia sem o procedimento de IR observados por 120 min. As amostras de intestino e coração foram processadas pelo método (RT-qPCR / Reverse transcriptase - quantitative Polymerase Chain Reaction) para determinar a expressão gênica de 84 genes relacionados ao estresse oxidativo ("t" de Student, p < 0,05). RESULTADOS: Observou-se no tecido intestinal (GIR) uma expressão significantemente aumentada em 65 (74,71%) genes em relação ao tecido normal (GC), e 37 (44,04%) genes estiveram hiperexpressos (maior que três vezes o limiar permitido pelo algoritmo). No tocante aos efeitos da I/R intestinal a distância no tecido cardíaco verificou-se a expressão significantemente aumentada de 28 genes (33,33%), mas somente oito genes (9,52%) se hiperexpressaram três vezes acima do limiar. Quatro (7,14%) desses oito genes se expressaram simultaneamente nos tecidos intestinal e cardíaco. No GIR notaram-se cardiomiócitos com núcleos de menor tamanho, picnóticos, ricos em heterocromatina e raros nucléolos, indicando sofrimento cardíaco. CONCLUSÃO: A I/R intestinal promoveu a hiperexpressão estatisticamente significante de oito genes associados ao estresse oxidativo a distância no tecido miocárdico.

Impact of Atrial Fibrillation Ablation on Left Ventricular Filling Pressure and Left Atrial Remodeling

Background:Left ventricular (LV) diastolic dysfunction is associated with new-onset atrial fibrillation (AF), and the estimation of elevated LV filling pressures by E/e' ratio is related to worse outcomes in patients with AF. However, it is unknown if restoring sinus rhythm reverses this process.Objective:To evaluate the impact of AF ablation on estimated LV filling pressure.Methods:A total of 141 patients underwent radiofrequency (RF) ablation to treat drug-refractory AF. Transthoracic echocardiography was performed 30 days before and 12 months after ablation. LV functional parameters, left atrial volume index (LAVind), and transmitral pulsed and mitral annulus tissue Doppler (e' and E/e') were assessed. Paroxysmal AF was present in 18 patients, persistent AF was present in 102 patients, and long-standing persistent AF in 21 patients. Follow-up included electrocardiographic examination and 24-h Holter monitoring at 3, 6, and 12 months after ablation.Results:One hundred seventeen patients (82.9%) were free of AF during the follow-up (average, 18 ± 5 months). LAVind reduced in the successful group (30.2 mL/m2 ± 10.6 mL/m2 to 22.6 mL/m2 ± 1.1 mL/m2, p < 0.001) compared to the non-successful group (37.7 mL/m2 ± 14.3 mL/m2 to 37.5 mL/m2 ± 14.5 mL/m2, p = ns). Improvement of LV filling pressure assessed by a reduction in the E/e' ratio was observed only after successful ablation (11.5 ± 4.5 vs. 7.1 ± 3.7, p < 0.001) but not in patients with recurrent AF (12.7 ± 4.4 vs. 12 ± 3.3, p = ns). The success rate was lower in the long-standing persistent AF patient group (57% vs. 87%, p = 0.001).Conclusion:Successful AF ablation is associated with LA reverse remodeling and an improvement in LV filling pressure.

The orthogonal subcategory problem in homotopy theory

It is known that, in a locally presentable category, localization exists with respect to every set of morphisms, while the statement that localization with respect to every (possibly proper) class of morphisms exists in locally presentable categories is equivalent to a large-cardinal axiom from set theory. One proves similarly, on one hand, that homotopy localization exists with respect to sets of maps in every cofibrantly generated, left proper, simplicial model category M whose underlying category is locally presentable. On the other hand, as we show in this article, the existence of localization with respect to possibly proper classes of maps in a model category M satisfying the above assumptions is implied by a large-cardinal axiom called Vopënka's principle, although we do not know if the reverse implication holds. We also show that, under the same assumptions on M, every endofunctor of M that is idempotent up to homotopy is equivalent to localization with respect to some class S of maps, and if Vopënka's principle holds then S can be chosen to be a set. There are examples showing that the latter need not be true if M is not cofibrantly generated. The above assumptions on M are satisfied by simplicial sets and symmetric spectra over simplicial sets, among many other model categories.

Collusion in growing and shrinking markets: empirical evidence from experimental duopolies

We study collusive behaviour in experimental duopolies that compete in prices under dynamic demand conditions. In one treatment the demand grows at a constant rate. In the other treatment the demand declines at another constant rate. The rates are chosen so that the evolution of the demand in one case is just the reverse in time than the one for the other case. We use a box-design demand function so that there are no issues of finding and co-ordinating on the collusive price. Contrary to game-theoretic reasoning, our results show that collusion is significantly larger when the demand shrinks than when it grows. We conjecture that the prospect of rapidly declining profit opportunities exerts a disciplining effect on firms that facilitates collusion and discourages deviation.