La fibrillation auriculaire, l'arythmie la plus fréquente en clinique, affecte 2.3 millions de patients en Amérique du Nord. Pour en étudier les mécanismes et les thérapies potentielles, des modèles animaux de fibrillation auriculaire ont été développés. La cartographie électrique épicardique à haute densité est une technique expérimentale bien établie pour suivre in vivo l'activité des oreillettes en réponse à une stimulation électrique, à du remodelage, à des arythmies ou à une modulation du système nerveux autonome. Dans les régions qui ne sont pas accessibles par cartographie épicardique, la cartographie endocardique sans contact réalisée à l'aide d'un cathéter en forme de ballon pourrait apporter une description plus complète de l'activité auriculaire. Dans cette étude, une expérience chez le chien a été conçue et analysée. Une reconstruction électro-anatomique, une cartographie épicardique (103 électrodes), une cartographie endocardique sans contact (2048 électrodes virtuelles calculées à partir un cathéter en forme de ballon avec 64 canaux) et des enregistrements endocardiques avec contact direct ont été réalisés simultanément. Les systèmes d'enregistrement ont été également simulés dans un modèle mathématique d'une oreillette droite de chien. Dans les simulations et les expériences (après la suppression du nœud atrio-ventriculaire), des cartes d'activation ont été calculées pendant le rythme sinusal. La repolarisation a été évaluée en mesurant l'aire sous l'onde T auriculaire (ATa) qui est un marqueur de gradient de repolarisation. Les résultats montrent un coefficient de corrélation épicardique-endocardique de 0.8 (expérience) and 0.96 (simulation) entre les cartes d'activation, et un coefficient de corrélation de 0.57 (expérience) and 0.92 (simulation) entre les valeurs de ATa. La cartographie endocardique sans contact apparait comme un instrument expérimental utile pour extraire de l'information en dehors des régions couvertes par les plaques d'enregistrement épicardique. / Atrial fibrillation is the most common clinical arrhythmia currently affecting 2.3 million patients in North America. To study its mechanisms and potential therapies, animal models of atrial fibrillation have been developed. Epicardial high-density electrical mapping is a well-established experimental instrument to monitor in vivo the activity of the atria in response to pacing, remodeling, arrhythmias and modulation of the autonomic nervous system. In regions that are not accessible by epicardial mapping, noncontact endocardial mapping performed through a balloon catheter may provide a more comprehensive description of atrial activity. In this study, a dog experiment was designed and analyzed in which electroanatomical reconstruction, epicardial mapping (103 electrodes), noncontact endocardial mapping (2048 virtual electrodes computed from a 64-channel balloon catheter), and direct-contact endocardial catheter recordings were simultaneously performed. The recording system was also simulated in a computer model of the canine right atrium. For simulations and experiments (after atrio-ventricular node suppression), activation maps were computed during sinus rhythm. Repolarization was assessed by measuring the area under the atrial T wave (ATa), a marker of repolarization gradients. Results showed an epicardial endocardial correlation coefficient of 0.8 (experiment) and 0.96 (simulation) between activation times, and a correlation coefficient of 0.57 (experiment) and 0.92 (simulation) between ATa values. Noncontact mapping appears to be a valuable experimental device to retrieve information outside the regions covered by epicardial recording plaques.

Le phénomène de destruction de l’ozone est un sujet vaste mettant en scène de nombreux processus. Il a pour origine l’émission de composés dits gaz sources (SGs) dans la troposphère. Récemment, les espèces à très courte durée de vie (VSLS) ont été identifiées comme SGs possibles. Cependant, elles ne possèdent pas un temps de vie suffisamment long pour atteindre directement la stratosphère. Les VSLS se dégradent au cours de leur transport, conduisant à des composés intermédiaires, les gaz produits (PGs). Les SGs et les PGs des VSLS vont entrer dans la stratosphère au niveau des régions équatoriales où règne un transport vertical rapide, la convection. Les SGs à temps de vie plus long peuvent accéder à la stratosphère par tous les types de transport possibles. Une fois dans la stratosphère, les SGs et PGs vont être convertis en espèces réactives capables de détruire l’ozone. Cette thèse présente l’étude des différentes étapes se produisant avant la destruction de l’ozone : l’émission et le transport des SGs dans l’atmosphère, leur chimie de dégradation au cours de leur transport et enfin leur contribution à la destruction de l’ozone. Les traceurs chimiques tels que CO sont tout d’abord utilisés pour mettre en évidence le transport des SGs et PGs de la troposphère à la stratosphère. Puis, deux études décrivant 2 types d’espèces différentes, entrant dans le processus de destruction de l’ozone, sont présentées : pour OCS (sulfure de carbonyle) et les VSLS bromés (CHBr3 et CH2Br2). OCS est l’un des principaux précurseurs d’aérosols sulfatés présents dans la stratosphère catalysant la destruction de l’ozone par chimie hétérogène. Cependant, sa contribution à cette couche comporte de nombreuses incertitudes. Ses sources d’émissions, sa répartition avec la latitude et sa contribution à la couche d’aérosols sulfatés sont présentées. La contribution des VSLS bromées au brome de la stratosphère est une question en cours de résolution. Leur chimie au cours de leur transport dans l’atmosphère est décrite de manière détaillée. / Ozone depletion is a complex subject involving several processes starting by the emission of the sources gases (SGs) in the lower troposphere. Recently the VSLS (very short lived substances) have been identified as potential SGs. However they do not have a lifetime long enough to reach directly the stratosphere. During the transport, the VSLS undergo degradation leading to products gases (PGs). The SGs and PGs of the VSLS reach the stratosphere in the Tropical region where a rapid vertical transport occurs, the convection. The SGs with longer lifetime can reach the stratosphere by any transport pathway from the location of their emissions. Once in stratosphere the SGs and PGs will be converted into reactive species able to deplete ozone. This thesis presents the study of the several steps occurring before the ozone depletion: SGs emission, SGs and PGs transport into the atmosphere, the chemical degradation occurring during their transport and finally their contribution to the ozone depletion. First, chemical tracers, as CO, are used to highlight the main pathways from the troposphere to the stratosphere. Then two studies of two different types of species entering in the process of ozone destruction are presented: for OCS (carbonyl sulfide) and the brominated VSLS (CHBr3 et CH2Br2). OCS is one of the sulfate aerosols precursors catalyzing the ozone depletion. However, OCS contribution to this layer has some uncertainties. OCS emission sources, the latitude repartition and the contribution to the sulfate aerosols are presented. The contribution of the brominated VSLS to the stratospheric bromine is a key issue that being almost resolved. The brominated VSLS chemical degradation during the atmospheric transport will be described in detail.

Introdução: O balão de contrapulsação intra-aórtico (BIA) é usado em uma variedade de contextos relacionados à disfunção miocárdica. Na cirurgia cardíaca, seu papel em desfechos clínicos é motivo de debate devido a resultados conflitantes de análises retrospectivas e limitações de recentes estudos prospectivos. Objetivo: O objetivo do presente estudo foi avaliar a eficácia e segurança do BIA eletivo na ocorrência de um desfecho composto de complicações clínicas incluindo mortalidade em pacientes de alto risco submetidos a cirurgia cardíaca de revascularização miocárdica (RM). Métodos: Estudo clínico prospectivo e randomizado realizado no Instituto do Coração (InCor) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Foram incluídos 181 pacientes adultos submetidos a cirurgia cardíaca de RM no período de abril de 2014 a junho de 2016, com um ou mais dos seguintes critérios: fração de ejeção menor ou igual a 40% e/ou EuroScore maior ou igual a 6. Os pacientes foram randomizados para uso do BIA logo após a indução anestésica ou para grupo controle. Após 24 horas do procedimento, o suporte com o balão intra-aórtico era suspenso se o paciente apresentasse índice cardíaco maior ou igual a 2,2 L/min/m2 com suporte inotrópico mínimo (dobutamina menor ou igual a 5 mcg/Kg/min) ou se o paciente apresentasse efeito colateral grave relacionado ao balão. O desfecho primário foi um composto de mortalidade e complicações graves em 30 dias após a cirurgia (choque cardiogênico, necessidade de reoperação, acidente vascular cerebral, insuficiência renal aguda, infecção de ferida esternal profunda e tempo de ventilação mecânica prolongada). Resultados: Dos pacientes incluídos no estudo, 90 foram alocados para a estratégia de uso do balão intra-aórtico eletivo e 91 para a estratégia controle. O desfecho primário foi observado em 47,8% do grupo BIA e em 46,2% do grupo controle (P=0,456). Não houve diferenças significativas entre os grupos BIA e controle respectivamente, em relação à ocorrência de óbito em 30 dias (14,4% vs 12,1%, P=0,600), choque cardiogênico (18,0% vs 18,9%, P=0,982), reoperação (3,4% vs 4,4%, P=1,000), tempo de ventilação mecânica prolongado (5,6% vs 7,7%, P=0,696), insuficiência renal aguda (22,2% vs 14,3%, P=0,123), acidente vascular cerebral (2,2% vs 2,2%, P=0,123) ou infecção de ferida operatória profunda (7,8% vs 14,3%, P=0,249). O tempo de uso de inotrópico foi significativamente maior no grupo BIA em comparação ao grupo controle (51 horas [32-94] vs 39 horas [25-66], P=0,007). O tempo de internação em UTI foi mais prolongado no grupo BIA comparado ao grupo controle (5 dias [3-8] vs 4 dias [3-6], P=0,035). O tempo de internação hospitalar foi semelhante entre os grupos (13 dias [9-18] vs 11 dias [8-17], P=0,302). Não houve diferença em relação a incidência de complicações relacionadas ao uso do BIA entre os dois grupos. Conclusão: A estratégia de uso do balão intra-aórtico eletivo em pacientes de alto risco submetidos a cirurgia de revascularização miocárdica não reduziu o desfecho combinado de óbito e/ou complicações graves em 30 dias / Introduction: The intra-aortic balloon pump (IABP) is used in a variety of clinical settings in which myocardial function is reduced. In cardiac surgery, its role on clinical outcomes is debated due to conflicting results of retrospective analysis and limitations of recent prospective studies. Objective: The purpose of this study was to evaluate the efficacy and safety of elective IABP use on outcomes in high-risk patients undergoing cardiac surgery. Methods: A prospective randomized controlled trial that evaluated 181 patients undergoing coronary artery bypass at the Heart Institute/University of Sao Paolo from 2014 April to 2016 June. Inclusion criteria were left ventricular ejection fraction (LVEF) <= 40% and/or EuroSCORE>= 6. Eligible patients were randomly assigned, in a 1:1 ratio, to IABP group (n=90) or control group (n=91). Removal of IABP catheter was accomplished after 24 hours of the procedure under the following circumstances: cardiac index >= 2.2 L/min/m2 and dobutamine infusion dose <= 5 ?g/kg/min. The catheter was immediately removed if a severe adverse event related to the procedure was detected. The primary outcome was the composite endpoint of mortality and major morbidity in 30 days after cardiac surgery (cardiogenic shock, need for reoperation, stroke, acute renal failure, mediastinitis and prolonged mechanical ventilation ( > 24 hours). Results: The primary outcome was observed in 47,8% in the IABP group and 46,2% in the control group (P=0,456). There were no differences in the primary outcome: 30-day mortality (14,4% vs 12,1%, P=0,600), cardiogenic shock (18,0% vs 18,9%, P=0,982), need for reoperation (3,4% vs 4,4%, P=1,000), prolonged mechanical ventilation (5,6% vs 7,7%, P=0,696), acute renal failure (22,2% vs 14,3%, P=0,123), stroke (2,2% vs 2,2%, P=0,123) or mediastinitis (7,8% vs 14,3%, P=0,249). Patients from the IABP group had a greater duration of inotrope use (51 hours [32-94] vs 39 hours [25-66], P=0,007) and longer intensive care unit length of stay (five days [3-8] vs four days [3-6], P=0,035). The length of hospital stay was similar (13 days [9-18] vs 11 days [8-17], P=0,302). There were no differences on the incidence of complications related to the IABP use in both groups. Conclusions: The elective IABP use did not reduce 30-day major complications in high-risk patients undergoing cardiac surgery

INTRODUÇÃO: As alterações da mucosa do estômago excluso após Derivação Gástrica em Y-de-Roux (DGYR) para tratamento da obesidade mórbida não são bem conhecidas. Atualmente, pouco se sabe a respeito das consequências da cirurgia, especialmente, considerando que tal técnica necessita de vigilância para possíveis alterações de mucosa. Adicionalmente, é possível que o refluxo duodenal biliopancreático para dentro do estômago excluso, sem tamponamento pela ingestão de alimentos, pode, após décadas, danificar a mucosa gástrica e provavelmente aumentar o risco de câncer gástrico. OBJETIVO: Analisar as alterações da mucosa do estômago excluso através de: índice de proliferação celular (Ki-67), apoptose (caspase 3 e Bcl-2), função hormonal (gastrina) e infiltrado inflamatório (CD3 e CD8). MÉTODOS: Enteroscopia de duplo balão foi realizada em 35 pacientes submetidos à DGYR com mais de 36 meses de cirurgia. Foram realizadas múltiplas biópsias no coto gástrico funcional e na mucosa do estômago excluso. Biópsias gástricas de 32 pacientes obesos não operados foram utilizadas como grupo controle. Biópsias endoscópicas foram seccionadas a partir de blocos de tecidos fixados em formalina e embebidos em parafina. Amostras de 4 m de espessura foram examinadas por imuno-histoquímica pelo método de estreptavidina-biotinaperoxidase. RESULTADOS: Os dois grupos foram comparados por idade, gênero, presença de gastrite, metaplasia intestinal e de Helicobacter pylori. O número médio de células de gastrina positivas foi de 55,5 (desvio padrão (DP) = 11,7) no grupo controle e 29,6 (DP = 7,9), nos casos, p= 0,0003. Índice de proliferação (Ki-67) nos casos (corpo=24,7%, antro=24,9%) foi significativamente maior em comparação com os controles (corpo=15% e antro=17,7%), p = 0,002 e 0,01 ,respectivamente. Imunoexpressão de caspase 3 foi maior nos controles em comparação ao estômago excluso (31 x 46%), p = 0,02. Não houve diferença estatística entre as expressões de CD3 , CD8 , e Bcl- 2 nos controles e nos casos. Não houve associação entre os resultados imuno-histoquímicos e a presença de Helicobacter pylori ou alterações histológicas. CONCLUSÕES: Proliferação celular está aumentada e a apoptose está diminuída na mucosa do estômago excluso em comparação com os controles obesos não operados. Alterações na renovação celular e nas secreções hormonais nestas condições podem ser relevantes em seguimento a longo prazo / INTRODUCTION: Mucosal alterations in the excluded stomach mucosal after Roux-en-Y gastric bypass for morbid obesity have not been clearly clarified. Currently, little is known regarding the long-term consequences of the surgical specially considering that the technique hinders surveillance for possible mucosal alterations. Indeed, it is possible that duodenal reflux of bile and pancreatic secretions without any buffering offered by food intake may, after decades, damage the gastric epithelium and lead to an increase gastric cancer risk. OBJECTIVE: This study aims to analyze the mucosal alterations (proliferative status (Ki-67), apoptosis (caspase 3 and Bcl-2), inflammatory response (CD3 and CD8) and for hormonal function (gastrin)) in the excluded stomach. METHODS: Double-balloon enteroscopy was performed in 35 patients who underwent Roux-en-Y gastric bypass longer than 36 months. Multiple biopsies of the proximal pouch and the excluded gastric mucosa were collected. Gastric biopsies from 32 non-operated obese patients were utilized as controls. Endoscopic biopsies were cut from tissue blocks fixed in formalin and embedded in paraffin. Sections 4 m thick were examined for immunoexpression using the streptavidin-biotin-peroxidase method. RESULTS: The two groups were compared for age, gender, gastritis, intestinal metaplasia, and presence of Helicobacter pylori. The mean number of positive gastrin cells was 55.5 (standart deviation (SD) = 11.7) in the control group and 29.6 (SD=7.9) in the cases, p=0.0003. Ki-67 proliferative index in cases (body=24.7%, antrum=24.9%) was significantly higher compared to controls (body=15.0% and antrum=17.7%), p=0.002 and 0.01, respectively. Caspase 3 immunoexpression was higher in the controls compared to the excluded stomach (46 vs. 31%), p=0.02. There was no statistical difference between CD3, CD8, and Bcl-2 immunoexpressions among the controls and cases. CONCLUSIONS: Cell proliferation is increased and apoptosis is downregulated in the excluded gastric mucosa compared to the non-operated obese controls. Alterations in cell turnover and in hormonal secretions in these conditions may be of important in long-term follow-up

Doppler radar wind profilers are already widely used to measure atmospheric winds throughout the free troposphere and stratosphere. Several methods have been developed to quantify atmospheric turbulence with such radars, but to date they have remained largely un-tested; this thesis presents the first comprehensive validation of one such method. Conventional in-situ measurements of turbulence have been concentrated in the surface layer, with some aircraft and balloon platforms measuring at higher altitudes on a case study basis. Radars offer the opportunity to measure turbulence near continuously, and at a range of altitudes, to provide the first long term observations of atmospheric turbulence above the surface layer. Two radars were used in this study, a Mesosphere-Stratosphere-Troposphere (MST) radar, at Capel Dewi, West Wales, and the Facility for Ground Based Atmospheric Measurements (FGAM) mobile boundary layer profiler. In-situ measurements were made using aircraft and tethered-balloon borne turbulence probes. The spectral width method was chosen for detailed testing, which uses the width of a radar's Doppler spectrum as a measure of atmospheric velocity variance. Broader Doppler spectra indicate stronger turbulence. To obtain Gaussian Doppler spectra (a requirement of the spectral width method), combination of between five and seven consecutive spectra was required. Individual MST spectra were particularly non-Gaussian, because of the sparse nature of turbulence at its observation altitudes. The width of Gaussian fits to the Doppler spectrum were compared to those from the `raw' spectrum, to ensure that non-atmospheric signals were not measured. Corrections for non-turbulent broadening, such as beam broadening, and signal processing, were investigated. Shear broadening was found to be small, and the errors in its calculation large, so no corrections for wind shear were applied. Beam broadening was found to be the dominant broadening contribution, and also contributed the largest uncertainty to spectral widths. Corrected spectral widths were found to correlate with aircraft measurements for both radars. Observing spectral widths over time periods of 40 and 60 minutes for the boundary layer profiler and MST radar respectively, gave the best measure of turbulence intensity and variability. Median spectral widths gave the best average over that period, with two-sigma limits (where sigma is the standard deviation of spectral widths) giving the best representation of the variability in turbulence. Turbulent kinetic energies were derived from spectral widths; typical boundary layer values were 0.13 m 2.s (-2) with a two-sigma range of 0.04-0.25 m 2.s (-2), and peaked at 0.21 m 2.s (-2) with a two-sigma range of 0.08-0.61 m 2.s (-2). Turbulent kinetic energy dissipation rates were also calculated from spectral widths, requiring radiosonde measurements of atmospheric stability. Dissipation rates compared well width aircraft measurements, reaching peaks of 1x10 (-3) m 2.s (-3) within 200 m of the ground, and decreasing to 1-2x10 (-5) m 2.s (-3) near the boundary layer capping inversion. Typical boundary layer values were between 1-3x10 (-4) m 2.s (-3). Those values are in close agreement with dissipation rates from previous studies.

Em pacientes obesos com diabetes mellitus tipo 2 (DM2), o controle glicêmico pode ser observado em poucos dias após derivação gástrica em Y de Roux (DGYR), antes de ocorrer significativa perda de peso. Dentre os mecanismos propostos para explicar esse benefício metabólico, aqueles que envolvem adaptações gastrintestinais (GI) em resposta às mudanças anatômicas cirúrgicas são os mais consistentes. O presente estudo avaliou a resposta global do transcriptoma gastrintestinal à DGYR em pacientes obesos responsivos à remissão pós-operatória de DM2 e sua correlação com marcadores de homeostase glicêmica. Vinte pacientes adultas obesas com DM2 e candidatas à DGYR foram incluídas, de acordo com critérios específicos. Todas foram submetidas à técnica de DGYR, por laparotomia padronizada e acompanhadas até um ano após DGYR, para classificação dos pacientes responsivos (R) e não responsivos (NR) à remissão de DM2, de acordo com o critério da American Diabetes Association (ADA). Variáveis clínicas e bioquímicas envolvidas na homeostase glicêmica foram avaliadas no pré-operatório e, mensalmente, até 90 dias pós-operatórios. Análises transcriptômicas gastrintestinais foram desenvolvidas por técnica de microarray (Genechip 1.0 ST Array; AffymetrixTM), a partir de RNA obtido de biópsias de estômago corpo alto (ECA), estômago corpo médio (ECM), duodeno, jejuno e íleo, coletadas por enteroscopia de duplo balão (EDB), no período pré-operatório e após 90 dias da DGYR. O método não paramétrico Rank Products (RP) foi utilizado para a seleção dos genes diferencialmente expressos (DEGs). Os DEGs identificados por RP foram submetidos ao programa Ingenuity Pathways Analysis (IPA), para a seleção de genes dentro das seguintes funções relacionadas à fisiopatologia do DM2: 1) Metabolismo dos Carboidratos; 2) Metabolismo Lipídico; 3) Metabolismo dos Aminoácidos, 4) Doenças Metabólicas e 5) Desordem do Sistema Endócrino. DEGs relacionados a essas cinco funções foram submetidos a análises de agrupamento hierárquico de Person, classificação funcional de ontologia gênica (GOslim ontology), análise de enriquecimento funcional (software DAVID, com uso de banco de dados KEGG e Biocarta) e de vias canônicas pelo software IPA. Essas análises foram feitas separadamente em pacientes R e NR. DEGs de interesse foram validados por RT-qPCR usando o sistema de ensaio Taqman® e equipamento 7500 FastTM (Life Technologies). O coeficiente de correlação de Spearman correlacionou variáveis clínicas e bioquímicas com variáveis transcriptômicas. Das 20 pacientes estudadas, 12 foram classificadas como R e 8 como NR. Nas 5 funções de interesse, o número de DEGs encontrado no grupo R foi: 99 (ECA), 26 (ECM), 62 (duodeno), 241 (jejuno) e 63 (íleo). Dentre os DEGs encontrados no duodeno, 8 apresentaram correlação positiva forte a muito forte (coeficiente de Spearman > 0,7) com alterações das concentrações sistêmicas de glicemia ou hemoglobina glicada. Destes, LDLR, MMP1, NPC1L1 e SLC2A5 foram submetidos à análise de RT-qPCR e validados pelo método. De acordo com as análises de enriquecimento funcional e vias canônicas entre grupos (R e NR), apenas a via LXR/RXR, representativa de DEGs encontrados no duodeno de pacientes R, apresentou associação com remissão do DM2. Nos demais segmentos gastrintestinais, essas análises não identificaram vias representativas relacionadas com DM2, embora alguns de seus DEGs estivessem potencialmente envolvidos com marcadores da homeostase glicêmica. Em conclusão, DGYR induziu modificações transcriptômicas gastrintestinais em pacientes obesos com remissão pós-operatória de DM2 e algumas delas foram associadas com marcadores de homeostase glicêmica, principalmente por meio de alterações na via LXR no duodeno / In obese patients with type 2 diabetes mellitus (T2DM), glycemic control is observed within a few days after Roux-en-Y gastric bypass (RYGB), even before significant weight loss. Among the mechanisms proposed to explain this metabolic benefit, those involving gastrointestinal (GI) adaptations in response to surgical anatomical rearreagement are the most consistent. The present study evaluated the global response of the gastrointestinal transcriptome to DGYR in obese patients responsive to postoperative remission of T2DM and its correlation with markers of glycemic homeostasis. Twenty adult obese patients with T2DM diagnosis and candidates to RYGB were included, according to specific criteria. All of them were submitted to standardized laparotomy RYGB surgery and followed until one year after RYGB, for the patients classification as responsive (R) and non-responsive (NR) to T2DM remission according to the American Diabetes Association (ADA) criteria. Clinical and biochemical variables involved in glycemic homeostasis were evaluated at preoperative and monthly up to 90 postoperative days. GI transcriptomic analyzes were performed by microarray technique (Genechip 1.0 ST Array; AffymetrixTM), in RNA samples obtained from biopsies of the stomach cardia (SC), stomach fundus (SF), duodenum, jejunum and ileum, collected by double-balloon enteroscopy (DBE) at pre-postoperative and 90 days after RYGB. The non-parametric Rank Products (RP) method was used for selection of differentially expressed genes (DEGs). DEGs identified by RP were submitted to the Ingenuity Pathways Analysis (IPA) program for its selection within the following functions: 1) Carbohydrate Metabolism; 2) Lipid Metabolism; 3) Amino Acids Metabolism, 4) Metabolic Diseases and 5) Endocrine System Disorder. DEGs related with these five functions were submitted to the analysis of Pearson hierarchical clustering, functional classification of gene ontology (GOslim), functional enrichment (DAVID software, using KEGG and Biocarta database), and canonical pathways (IPA). These analyzes were performed separately in R and NR groups. DEGs of interest were validated by RT-qPCR using Taqman® assays in 7500 FastTM (Life Technologies). The Spearman correlation coefficient correlated clinical and biochemical variables with DEGs. From the 20 patients studied, 12 were classified as R and 8 as NR. In the 5 functions of interest, the number of DEGs found in R group were: 99 (SC), 26 (SF), 62 (duodenum), 241 (jejunum) and 63 (ileum). Among the DEGs found in the duodenum, 8 presented a strong to a very strong positive correlation (Spearman coefficient > 0.7) with systemic concentrations of glycemia or glycated hemoglobin. Of these genes, LDLR, MMP1, NPC1L1 and SLC2A5 were subjected to RT-qPCR analysis and validated by the method. According to the functional enrichment and canonical pathways analyzes between groups (R and NR), only the LXR/RXR pathway, representative of DEGs found in the duodenum of R patients, was associated with T2DM remission. In the other GI segments, these analyzes did not identify representative pathways related to T2DM, although some of their DEGs were potentially involved with markers of glycemic homeostasis. In conclusion, RYGB induced gastrointestinal transcriptomics changes in obese patients with postoperative remission of T2DM and some of these were associated with markers of glycemic homeostasis, mainly by changes in LXR pathway in the duodenum

Introdução: A cirurgia cardíaca resulta em taxa considerável de complicações neurológicas, incluindo delirium, disfunção cognitiva e acidente vascular cerebral isquêmico. Supõe que a fisiopatologia envolva embolia, aterotrombose, hipofluxo, redução do débito cardíaco e alterações da autorregulação cerebral. O balão de contrapulsação intra-aórtico (BIA) é um dispositivo de assistência circulatória comumente utilizado no perioperatório de pacientes de alto risco com o objetivo de otimização do débito cardíaco e da perfusão coronária. Apesar do benefício hemodinâmico do BIA, não é conhecido seu efeito na hemodinâmica encefálica. Objetivo: Avaliar os efeitos do BIA na hemodinâmica encefálica em pacientes de alto risco submetido a cirurgia cardíaca com circulação extracorpórea (CEC). Métodos: Trata-se de um subestudo do estudo clínico prospectivo e randomizado \"Balão de contra-pulsação intra-aórtico eletivo em pacientes de alto risco submetidos a cirurgia cardíaca\", realizado no Instituto do coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo entre 2014 e 2016. Dos 181 pacientes incluídos no estudo randomizado, 67 pacientes foram incluídos no subestudo. Os pacientes eram adultos, submetidos a cirurgia cardíaca de revascularização miocárdica (RM) com fração de ejeção menor ou igual a 40% e/ou EuroScore maior ou igual a 6. Os mesmos foram randomizados para uso do BIA logo após a indução anestésica ou para grupo controle. A velocidade de fluxo sanguíneo cerebral (VFSC) pelo ultrassom Doppler transcraniano e a pressão arterial (PA) pelo Finometer foram continuamente gravados por 5 minutos antes da cirurgia (T1), 24h após (T2) e 7 dias após (T3). O índice de autorregulação (ARI) foi estimado através da resposta ao degrau da VFSC a mudanças na PA, derivados da análise da função de transferência. As seguintes complicações clínicas neurológicas foram avaliadas: delirium, disfunção cognitiva e acidente vascular cerebral isquêmico. Resultados: Dos pacientes incluídos no estudo, 34 foram alocados para a estratégia de uso profilático do balão intra-aórtico e 33 para a estratégia controle. Não houve diferenças significativas entre os grupos BIA e controle respectivamente, nos três tempos de avaliação, em relação ao ARI (T1 - 5,5 ± 1,9 vs 5,7 ± 1,7; T2 - 4,0 ± 1,9 vs 4,1 ± 1,6; T3 - 5,7 ± 2,0 vs 5,7 ± 1,6, P= 0,978) e em relação à VFSC (T1 - 57,3 ± 19,4 vs 59,3 ± 11,8; T2 - 74,0 ± 21,6 vs 74,7 ± 17,5; T3 - 71,1 ± 21,3 vs 68,1 ± 15,1; P=0,952). O grupo BIA e o grupo controle apresentaram incidência semelhante de complicações neurológicas (delirium na unidade de terapia intensiva - 26,5% vs 24,2%, P=0,834, acidente vascular cerebral isquêmico - 3,0% vs 2,9%, P=1,00, e declínio cognitivo pós-operatório através das escalas Mini Mental State Examination MMSE - 16,7% vs 40,7%; P= 0,073 e Avaliação Cognitiva Montreal MoCA - 79,16% vs 81,5%; P= 1,000). Conclusões: O uso profilático do BIA em pacientes de alto risco submetidos à cirurgia de revascularização do miocárdio não altera a hemodinâmica encefálica e não está associado ao aumento de complicações neurológicas como delirium, declínio cognitivo e acidente vascular cerebral isquêmico / Introduction: Cardiac surgery is associated with a high incidence of neurologic complications, such as delirium, cognitive decline and stroke. The pathophysiology probably involves embolism, thrombosis, decreased cardiac output and abnormalities in cerebral autoregulation. The intraaortic balloon pump (IABP) is an assist device commonly in high-risk patients undergoing cardiac surgery aiming to increase the cardiac output and to improve the coronary perfusion. However, the effect of the IABP on the cerebral hemodynamic is unknown. Objectives: To assess the effect of IABP on cerebral hemodynamics in high-risk patients undergoing cardiac surgery with cardio-pulmonary bypass (CPB). Methods: This is a substudy of the randomized controlled trial \"Intraaortic Balloon Counterpulsation in Patients Undergoing Cardiac Surgery (IABCS trial)\", performed at the Heart Institute/University of Sao Paulo, from 2014 to 2016. Of the 181 patients included in the IABCS, 67 were included if they were submitted to cardiac surgery and if they had one of these two criteria: left ventricular ejection fraction equal or lower than 40% and/or EuroSCORE equal or higher than 6. Patients were allocated to the strategy of prohylatic IABP after anesthesia induction or to control. Cerebral blood flow velocity (CBFV) through transcranial Doppler and blood pressure (BP) through Finometer or intra-arterial line were continuously recorded over 5 minutes preoperatively (T1), after 24h (T2) and 7 days after surgery (T3). Autoregulation index (ARI) was estimated from the CBFV response to a step change in BP derived by transfer function analysis. The following complications neurologic were evaluated: delirium, cognitive decline and stroke. Results: Of the included patients, 34 were allocated to the IABP group and 33 to control group. There were no significant differences between the IABP and the control respectively in the following parameters: ARI (T1 - 5.5 ± 1.9 vs 5.7 ± 1.7; T2 - 4.0 ± 1.9 vs 4.1 ± 1.6; T3 - 5.7 ± 2.0 vs 5.7 ± 1.6, P= 0.978), CBFV (T1 - 57.3 ± 19.4 vs 59.3 ± 11.8; T2 - 74.0 ± 21.6 vs 74.7 ± 17.5; T3 - 71.1 ± 21.3 vs 68.1 ± 15.1; P=0.952). Both groups (IABP and control) had similar incidence of neurological complications (delirium - 26.5% vs 24.2%, P=0.834, stroke - 3.0% vs 2.9%, P=1.00, and cognitive decline through the scales Mini Mental State Examination MMSE - 16,7% vs 40,7%; P= 0.073 and Montreal Cognitive Assessment MoCA - 79.16% vs 81.5%; P= 1.000). Conclusions: The prophylactic use of IABP in high-risk patients undergoing cardiac surgery does not change the cerebral hemodynamic and is not associated with higher incidence of neurologic complications such as delirium, cognitive decline and stroke

This work is dealing with the design and implementation of an embedded system for aerology measuring. The aim of the system is to monitor atmospheric states during an ascent in the suspension under an meteorological balloon.   First of all, attention is given to the Earth's atmosphere and its quantities, then an overview of existing systems for performing aerological measurements. The core of the work is focused on the choice of measurement techniques and the selection of suitable measuring elements for a given scenario. The aerological probe is using atmospheric sensors HIH-8131-021-001, MS5611-01BA03 and PT1000-550 for temperature sensing, while GNSS data is received using the MAX-M8Q-0 module and the measured data is stored on a microSD card and transmitted in parallel using the MTX2-434.650-10 radio module. The system is controlled by STM32L1 from STMicroelectronics programmed in C using  HAL abstraction layer.

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Background: The current goal of treatment after acute ischemic stroke is the increase of cerebral blood flow (CBF) in ischemic brain tissue. Intra-aortic balloon pump (IABP) counterpulsation in the setting of cardiogenic shock is able to reduce left ventricular afterload and increase coronary blood flow. The effects of an IABP on CBF have not been sufficiently examined. We hypothesize that the use of an IABP especially enhances cerebral blood flow in patients with pre-existing heart failure. Methods: In this pilot study, 36 subjects were examined to investigate the effect of an IABP on middle cerebral artery (MCA) transcranial Doppler (TCD) flow velocity change and relative CBF augmentation by determining velocity time integral changes (ΔVTI) in a constant caliber of the MCA compared to a baseline measurement without an IABP. Subjects were divided into two groups according to their left ventricular ejection fraction (LVEF): Group 1 LVEF >30% and Group 2 LVEF ≤30%. Results: Both groups showed an increase in CBF using an IABP. Patients with a LVEF ≤30% showed a significantly higher increase of ΔVTI in the MCA under IABP augmentation compared to patients with a LVEF >30% (20.9% ± 3.9% Group 2 vs.10.5% ± 2.2% Group 1, p<0,05). The mean arterial pressure (MAP) increased only marginally in both groups under IABP augmentation. Conclusions: IABP improves cerebral blood flow, particularly in patients with pre-existing heart failure and highly impaired LVEF. Hence, an IABP might be a treatment option to improve cerebral perfusion in selected patients with cerebral misperfusion and simultaneously existing severe heart failure.