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Stem cells can either differentiate into more specialized cells or undergo self-renewal. Several lines of evidence from different organisms suggest that these processes depend on the post-transcriptional regulation of gene expression. The presence of the PUF [Pumilio/FBF (fem-3 binding factor)] domain defines a conserved family of RNA binding proteins involved in repressing gene expression. It has been suggested that a conserved function of PUF proteins is to repress differentiation and sustain the mitotic proliferation of stem cells. In humans, Pumilio-2 (PUM2) is expressed in embryonic stem cells and adult germ cells. Here we show that PUM2 is expressed in a subpopulation of adipose-derived stem cell (ASC) cultures, with a granular pattern of staining in the cytoplasm. Protein levels of PUM2 showed no changes during the differentiation of ASCs into adipocytes. Moreover, RNAi knockdown of pum2 did not alter the rate of adipogenic differentiation compared with wild-type control cells. A ribonomic approach was used to identify PUM2-associated mRNAs. Microarray analysis showed that PUM2-bound mRNAs are part of gene networks involved in cell proliferation and gene expression control. We studied pum2 expression in cell cultures with low or very high levels of proliferation and found that changes in pum2 production were dependent on the proliferation status of the cell. Transient knockdown of pum2 expression by RNAi impaired proliferation of ASCs in vitro. Our results suggest that PUM2 does not repress differentiation of ASCs but rather is involved in the positive control of ASCs division and proliferation.

OBJETIVO: Avaliar os resultados imediatos da operação para revascularização do miocárdio sem circulação extracorpórea, analisando-se complicações e mortalidade. MÉTODO: Foram submetidos à operação para revascularização do miocárdio sem circulação extracorpórea 1440 pacientes. A técnica operatória consistiu em oclusão proximal da artéria abordada, aplicação do ponto de LIMA na deflexão pericárdica posterior e estabilização da artéria alvo com estabilizador de sucção. As anastomoses distais foram feitas inicialmente. RESULTADOS: Entre os pacientes avaliados, 924 eram ao sexo masculino, com idade média de 63,12±8,76 anos. A fração de ejeção era normal em 749 pacientes. Setecentos e quarenta (51,4%) pacientes tinham antecedente de infarto do miocárdio. Seiscentos e oitenta e sete (47,6%) pacientes encontravam-se em classe funcional III ou IV. O EuroSCORE médio foi de 4,93±3,32. A média de anastomoses distais foi de 3,12±1,23 por paciente. Mil cento e setenta e três (81,5%) pacientes permaneceram menos de 12 horas em ventilação mecânica, sendo que destes, 888 (61,7%) permaneceram menos de 6 horas entubados. A permanência em UTI foi de uma noite em 330 (22,8%) pacientes e de duas noites em 930 (64,6%). Cento e oitenta e dois (12,4%) pacientes permaneceram três ou mais noites na UTI. Quanto às complicações, três (0,2%) pacientes apresentaram insuficiência renal, seis (0,4%) tiveram acidente vascular cerebral, 19 (1,3%) foram reoperados por sangramento, 19 (1,3%) tiveram mediastinite, 18 (1,25%) infarto agudo do miocárdio e 212 (14,7%) apresentaram fibrilação atrial. Houve 50 (3,5%) óbitos, sendo 29 (2,5%) entre 1148 pacientes operados eletivamente, nove (4,7%) entre 190 pacientes submetidos a reoperação coronariana e 12 (11,7%) entre 102 pacientes operados em caráter de emergência. CONCLUSÃO: Com A evolução da tecnologia biomédica, todos os vasos do coração passaram a ser abordados. Estes dados sugerem que a operação para revascularização do miocárdio é segura e eficaz, podendo ser aplicada em todos os pacientes que necessitem de cirurgia coronariana com baixos índices de complicações e mortalidade. OBJECTIVE: To evaluate the immediate postoperative results of off-pump myocardium revascularization surgery by analyzing complications and mortality. METHOD: A total of 1440 patients were submitted to off-pump myocardium revascularization. The surgical technique is consisted in proximal occlusion of the approached artery, the application of the LIMA graft in the posterior pericardial deflection and stabilization of the target artery with a suction stabilizer. The distal anastomoses were performed first. RESULTS: Among the patients evaluated, 924 were male and 516 were female,with a mean age of 63.12 ± 8.76 years. The ejection fraction was normal in 749 patients, 740 (51.4%) patients had suffered previous myocardial infarction and 687 (47.6%) patients were in functional class III or IV. The mean EuroSCORE was 4.93 ± 3.32. The mean number of dial anastomoses was 3.12 ± 1.23 per patient. A total of 1173 (81.5%) patients remained less than 12 hours on mechanical ventilation and among them, 888 (61.7%) remained for less than six hours. The stay in the ICU was of one night for 330 (22.8%) patients, for two nights for 930 (64.6%) patients and 182 (12.4%) patients remained three or more nights. In regards to complications, three (0.2%) patients presented with renal insufficiency, six (0.4%) patients suffered stroke, 19 (1.3%) patients were reoperated for bleeding, 19 (1.3%) patients had mediastinitis, 18 (1.25%) patients suffered severe myocardial infarction and 212 (14.7%) presented atrial fibrillation. There were 50 (3.5%) deaths, 29 (2.5%) of them being among the 1148 operated electively, nine (4.7%) among 190 patients submitted to coronary re-operation and 12 (11.7%) among 102 patients undergoing emergency operations. CONCLUSION: With the evolution of biomedical technological, all the vessels of the heart are now approached. These data suggest that the operation for myocardial revascularization is safe and efficient. It can be applied to all patients who need coronary surgery, with low rates of complication and mortality.

Mesenchymal stem cells (MSCs) have received special attention for cardiomyoplasty because several studies have shown that they differentiate into cardiomyocytes both in vitro and in vivo. Nitric oxide (NO) is a free radical signaling molecule that regulates several differentiation processes including cardiomyogenesis. Here, we report an investigation of the effects of two NO agents (SNAP and DEA/NO), able to activate both cGMP-dependent and -independent pathways, on the cardiomyogenic potential of bone marrow-derived mesenchymal stem cells (BM-MSCs) and adipose tissue-derived stem cells (ADSCs). The cells were isolated, cultured and treated with NO agents. Cardiac- and muscle-specific gene expression was analyzed by indirect immunofluorescence, flow cytometry, RT-PCR and real-time PCR. We found that untreated (control) ADSCs and BM-MSCs expressed some muscle markers and NO-derived intermediates induce an increased expression of some cardiac function genes in BM-MSCs and ADSCs. Moreover, NO agents considerably increased the pro-angiogenic potential mostly of BM-MSCs as determined by VEGF mRNA levels.

FUNDAMENTO: A fibrilacao atrial e a mais comum complicacao no pos-operatorio de revascularizacao miocardica, aumentando a incidencia de morbi-mortalidade. OBJETIVO: O proposito deste estudo prospectivo e randomizado foi testar a hipotese de que a estimulacao cardiaca temporaria biatrial reduz a incidencia da fibrilacao atrial no pos-operatorio de revascularizacao miocardica. METODOS: Em uma casuistica de 98 pacientes nao-consecutivos, submetidos a revascularizacao miocardica sem circulacao extracorporea, foram implantados respectivamente dois eletrodos temporarios em atrio direito e em atrio esquerdo e conectados a cada par de saida atrial do marcapasso, alem dos eletrodos implantados no ventriculo direito. Foram randomizados dois grupos (controle: 49 pacientes sem a estimulacao biatrial; terapeutico: 49 pacientes com a estimulacao biatrial). As variaveis de interesse foram: fibrilacao atrial (presenca ou nao), tempo de hospitalizacao. RESULTADOS: A incidencia de fibrilacao atrial foi de 36,73% no grupo controle e 14,29% no grupo terapeutico (p=0,0194). O tempo de hospitalizacao foi de 7,00±2,82 dias nos pacientes sem fibrilacao atrial (n=73), e de 9,20±2,87 dias nos pacientes com fibrilacao atrial (n=25) (p=0,0001). A idade foi importante preditor da arritmia, variou de 62,34±9,00 anos no grupo sem fibrilacao atrial, e de 67,20±7,42 anos no grupo com fibrilacao atrial (p=0,0170). CONCLUSAO: A estimulacao temporaria biatrial profilatica e efetiva na prevencao da fibrilacao atrial, quando comparada ao grupo controle. Permanencia hospitalar foi maior nos pacientes que apresentaram fibrilacao atrial no pos-operatorio e a idade foi importante preditor para o desenvolvimento da arritmia.

OBJETIVO: Avaliar os resultados imediatos das anastomoses mecânicas aorto-safena, comparando-as às anastomoses convencionais. MÉTODO: Foram analisados 12 pacientes, com idade média de 62,33 ± 7,30 anos, sendo 10 (83,3%) do sexo masculino. Os pacientes foram submetidos à operação sem circulação extracorpórea, com 33 anastomoses proximais avaliadas, sendo 21 anastomoses convencionais e 12 feitas com o conector aórtico Symmetry da St. Medical. Foram analisados tempo gasto para confecção da anastomose, fluxo livre com pressão arterial sistólica de 100 mmHg e patência no 4º dia de pós-operatório. RESULTADOS: A anastomose mecânica foi empregada com sucesso em todos os pacientes. Um paciente apresentou alterações eletrocardiográficas compatíveis com IAM, no 2º dia de pós-operatório, sendo encaminhado para reestudo angiográfico, que evidenciou oclusão de anastomose proximal convencional para ramo marginal. Três pacientes apresentaram fibrilação atrial. Não houve óbitos nesta série. O tempo médio gasto para realização da anastomose mecânica foi de 44,08 ± 9,26 segundos contra 3,86 ± 0,61 minutos da anastomose convencional (p = 0,0022). O fluxo livre médio observado nas anastomoses mecânicas foi de 302,75 ± 82,76 ml/min contra 190,75±51,53 ml/min (p = 0,0022). No reestudo angiográfico, feito no 4º pós-operatorio, detectou-se oclusão de três anastomoses mecânicas contra nenhuma nova oclusão das anastomoses convencionais (p = 0,2500). CONCLUSÃO: O presente estudo apresentou uma superioridade estatisticamente significativa em favor das anastomoses mecânicas da veia safena com aorta, quando avaliado tempo para confecção da anastomose e fluxo livre. Em relação à condição da artéria na angiografia pósoperatória, não se pode afirmar que exista diferença estatisticamente significativa entre os procedimentos estudados.

OBJETIVO: Avaliar os resultados imediatos das anastomoses mecânicas aorto-safena, comparando-as às anastomoses convencionais. MÉTODO: Foram analisados 12 pacientes, com idade média de 62,33 ± 7,30 anos, sendo 10 (83,3%) do sexo masculino. Os pacientes foram submetidos à operação sem circulação extracorpórea, com 33 anastomoses proximais avaliadas, sendo 21 anastomoses convencionais e 12 feitas com o conector aórtico Symmetry da St. Medical. Foram analisados tempo gasto para confecção da anastomose, fluxo livre com pressão arterial sistólica de 100 mmHg e patência no 4º dia de pós-operatório. RESULTADOS: A anastomose mecânica foi empregada com sucesso em todos os pacientes. Um paciente apresentou alterações eletrocardiográficas compatíveis com IAM, no 2º dia de pós-operatório, sendo encaminhado para reestudo angiográfico, que evidenciou oclusão de anastomose proximal convencional para ramo marginal. Três pacientes apresentaram fibrilação atrial. Não houve óbitos nesta série. O tempo médio gasto para realização da anastomose mecânica foi de 44,08 ± 9,26 segundos contra 3,86 ± 0,61 minutos da anastomose convencional (p = 0,0022). O fluxo livre médio observado nas anastomoses mecânicas foi de 302,75 ± 82,76 ml/min contra 190,75±51,53 ml/min (p = 0,0022). No reestudo angiográfico, feito no 4º pós-operatorio, detectou-se oclusão de três anastomoses mecânicas contra nenhuma nova oclusão das anastomoses convencionais (p = 0,2500). CONCLUSÃO: O presente estudo apresentou uma superioridade estatisticamente significativa em favor das anastomoses mecânicas da veia safena com aorta, quando avaliado tempo para confecção da anastomose e fluxo livre. Em relação à condição da artéria na angiografia pósoperatória, não se pode afirmar que exista diferença estatisticamente significativa entre os procedimentos estudados. OBJECTIVE: To evaluate the immediate results of mechanical aorto-saphenous anastomosis compared with conventional anastomosis. METHOD: We evaluated 12 patients. The mean age ranged from 62.33 ± 7.30 years. Of 12 patients submitted to surgery without extracorporeal circulation, 10 (83.3%) patients were male. Thirty-three proximal anastomoses were evaluated, 21 of them being performed through the conventional manner and 12 with the St. Jude Symmetry aortic connector. The time spent on anastomosis, and free flow and patency on the 4th day postoperative were analysed. RESULTS: The mechanical anastomosis was successfully performed in all patients. Electrocardiographic alteration compatible with myocardial infarctation (MI) on the 2nd day postoperative was observed only in one patient. The patient was referred to angiographic restudy, becoming evident a conventional proximal anastomosis occlusion for the marginal branch. Three patients had atrial fibrillation. The average time spent to perform the mechanical anastomosis was 44.08 ± 9.26 seconds against 3.86 ± 0.61 minutes of the conventional anastomosis (p = 0.0022). The average blood free flow observed in the mechanical anastomosis was 302.75 ± 82.76 mL/min versus 190.75 ± 51.53 mL/min (p = 0.0022). In the angiographic restudy performed on the 4th postoperative day, it was detected the occlusin of three mechanical anastomosis. There was no new conventional anastomosis (p = 0.2500). CONCLUSION: The present study showed a statistically significant superiority for mechanical anastomosis of the saphenous vein with the aorta when evaluated the blood free flow and the time to perform the anastomosis. In relation to the artery condition in the postoperative angiography, one cannot say there was statistically significant difference between the procedures studied.

OBJECTIVE: To assess off-pump myocardial revascularization in patients with significant left ventricular dysfunction. METHODS: Four hundred and five patients with an ejection fraction less than 35% underwent myocardial revascularization without extracorporeal circulation. The procedure was performed with the aid of a suction stabilizer and the LIMA stitch. The distal anastomoses were performed first. RESULTS: A total of 405 patients were evaluated whose mean age was 63.4±9.78 years. Two hundred and seventy-nine patients were men (68.8%). With regard to risk factors, 347 patients were hypertensive, 194 were smokers, 202 were dyslipidemic, and 134 had diabetes. Two hundred and sixty patients were classified as NYHA functional class III and IV. Twenty patients suffered from chronic renal disease and were under dialysis. Fifty-one underwent emergency surgery, and 33 had been previously operated on. The mean ejection fraction was 27.2±3.54%. The mean EuroSCORE was 8.46±4.41. The mean number of anastomoses performed was 3.03±1.54 per patient. Forty-nine patients (12%) needed an intra-aortic balloon inserted after induction of anesthesia, whereas 73 (18%) needed inotropic support during the perioperative period. As to complications, 2 patients (0.49%) had renal failure, 2 had mediastinitis (0.49%), 7 (1.7%) needed to be reoperated because of bleeding, 5 patients (1.2%) suffered acute myocardial infarction, and 70 patients (17.3%) experienced atrial fibrillation. Eighteen (4.4%) patients died. CONCLUSION: Based on the data above, we concluded that myocardial revascularization without extracorporeal circulation in patients with left ventricular dysfunction is a safe and effective technique, and an alternative for high-risk patients. Results obtained were better than those predicted by EuroSCORE.

OBJETIVO: Analisar evolução hospitalar dos pacientes portadores de insuficiência renal crônica (IRC) em hemodiálise, submetidos a operação sem circulação extracorpórea (CEC). MÉTODO: Cinqüenta e um pacientes portadores de IRC foram submetidos à operação sem CEC. A hemodiálise foi realizada no dia anterior à operação e no dia seguinte. A revascularização do miocárdio foi realizada com ponto de LIMA e estabilizador por sucção. RESULTADOS: A idade média foi de 61,28±11,09 anos e 31 (58,8%) pacientes eram do sexo feminino. A classe funcional predominante foi a IV em 21 (41,1%) dos pacientes. A fração de ejeção do ventrículo esquerdo era ruim em 21 (41,1%) pacientes. O EUROSCORE médio desta série de pacientes foi de 7,65±3,83. O número médio de artérias coronárias revascularizadas foi de 3,1±0,78 por paciente. O tempo médio de ventilação mecânica foi de 3,78±4,35 horas. A permanência média na CTI foi de 41,9±13,8 horas, enquanto a média de permanência hospitalar foi de 6,5±1,31 dias. Quanto às complicações, nove (17,6%) pacientes desenvolveram FA e um (1,9%) apresentou quadro de AVC isquêmico, com boa recuperação durante a internação. Não houve óbito nesta série. CONCLUSÃO: Pacientes renais crônicos submetidos à hemodiálise sempre foram uma população de alto risco para revascularização do miocárdio. A ausência de CEC, aparentemente, cursa com baixos índices de morbi-mortalidade nesta população.

OBJETIVO: Analisar evolução hospitalar dos pacientes portadores de insuficiência renal crônica (IRC) em hemodiálise, submetidos a operação sem circulação extracorpórea (CEC). MÉTODO: Cinqüenta e um pacientes portadores de IRC foram submetidos à operação sem CEC. A hemodiálise foi realizada no dia anterior à operação e no dia seguinte. A revascularização do miocárdio foi realizada com ponto de LIMA e estabilizador por sucção. RESULTADOS: A idade média foi de 61,28±11,09 anos e 31 (58,8%) pacientes eram do sexo feminino. A classe funcional predominante foi a IV em 21 (41,1%) dos pacientes. A fração de ejeção do ventrículo esquerdo era ruim em 21 (41,1%) pacientes. O EUROSCORE médio desta série de pacientes foi de 7,65±3,83. O número médio de artérias coronárias revascularizadas foi de 3,1±0,78 por paciente. O tempo médio de ventilação mecânica foi de 3,78±4,35 horas. A permanência média na CTI foi de 41,9±13,8 horas, enquanto a média de permanência hospitalar foi de 6,5±1,31 dias. Quanto às complicações, nove (17,6%) pacientes desenvolveram FA e um (1,9%) apresentou quadro de AVC isquêmico, com boa recuperação durante a internação. Não houve óbito nesta série. CONCLUSÃO: Pacientes renais crônicos submetidos à hemodiálise sempre foram uma população de alto risco para revascularização do miocárdio. A ausência de CEC, aparentemente, cursa com baixos índices de morbi-mortalidade nesta população. OBJECTIVE: To analyze the hospital outcomes of patients, with chronic renal insufficiency in the hemodialysis, submitted to OPCAB. METHOD: Fifty-one patients with chronic renal insufficiency were submitted to OPCAB. Hemodialysis was performed on the day before and the day after the operation. Myocardial revascularization was performed using LIMA's suture and suction stabilization. RESULTS: Fifty-one patients, with an averageof 61.28±11.09 years, were analyzed. Thirty patients (58.8%) were female. The predominant functional class was IV in 21 (41.1%) of the patients. The left ventricle ejection fraction was dire in 21 (41.1%) patients. The mean EUROSCORE of this series was 7.65±3.83 and the mean number of distal anastomosis was 3.1±0.78 per patient. The average time of mechanical ventilation was 3.78±4.35 hours and the mean ICU stay was 41.9±13.8 hours, while the average hospitalization was 6.5±1.31 days. In respect to complications, nine (17.6%) of the patients developed atrial fibrilation, and one (1.9%) patient presented with a case of ischemic stroke but had a good recovery during hospitalization. There were no deaths in this series. CONCLUSION: Chronic renal patients submitted to hemodialysis were always a high risk population for myocardial revascularization. In this series, the absence of extracorporeal circulation appeared to be safe and efficient in this special subgroup of patients. The operations were performed with low indices of complications, absence of deaths and relatively low stays in the ICU and in hospital.

To evaluate the immediate results of mechanical aorto-saphenous anastomosis compared with conventional anastomosis.We evaluated 12 patients. The mean age ranged from 62.33 +/- 7.30 years. Of 12 patients submitted to surgery without extracorporeal circulation, 10 (83.3%) patients were male. Thirty-three proximal anastomoses were evaluated, 21 of them being performed through the conventional manner and 12 with the St. Jude Symmetry aortic connector. The time spent on anastomosis, and free flow and patency on the 4th day postoperative were analysed.The mechanical anastomosis was successfully performed in all patients. Electrocardiographic alteration compatible with myocardial infarctation (MI) on the 2nd day postoperative was observed only in one patient. The patient was referred to angiographic restudy, becoming evident a conventional proximal anastomosis occlusion for the marginal branch. Three patients had atrial fibrillation. The average time spent to perform the mechanical anastomosis was 44.08 +/- 9.26 seconds against 3.86 +/- 0.61 minutes of the conventional anastomosis (p = 0.0022). The average blood free flow observed in the mechanical anastomosis was 302.75 +/- 82.76 mL/min versus 190.75 +/- 51.53 mL/min (p = 0.0022). In the angiographic restudy performed on the 4th postoperative day, it was detected the occlusin of three mechanical anastomosis. There was no new conventional anastomosis (p = 0.2500).The present study showed a statistically significant superiority for mechanical anastomosis of the saphenous vein with the aorta when evaluated the blood free flow and the time to perform the anastomosis. In relation to the artery condition in the postoperative angiography, one cannot say there was statistically significant difference between the procedures studied.

To analyze the hospital outcomes of patients, with chronic renal insufficiency in the hemodialysis, submitted to OPCAB.Fifty-one patients with chronic renal insufficiency were submitted to OPCAB. Hemodialysis was performed on the day before and the day after the operation. Myocardial revascularization was performed using LIMA's suture and suction stabilization.Fifty-one patients, with an average of 61.28+/-11.09 years, were analyzed. Thirty patients (58.8%) were female. The predominant functional class was IV in 21 (41.1%) of the patients. The left ventricle ejection fraction was dire in 21 (41.1%) patients. The mean EUROSCORE of this series was 7.65+/-3.83 and the mean number of distal anastomosis was 3.1+/-0.78 per patient. The average time of mechanical ventilation was 3.78+/-4.35 hours and the mean ICU stay was 41.9+/-13.8 hours, while the average hospitalization was 6.5+/-1.31 days. In respect to complications, nine (17.6%) of the patients developed atrial fibrilation, and one (1.9%) patient presented with a case of ischemic stroke but had a good recovery during hospitalization. There were no deaths in this series.Chronic renal patients submitted to hemodialysis were always a high risk population for myocardial revascularization. In this series, the absence of extracorporeal circulation appeared to be safe and efficient in this special subgroup of patients. The operations were performed with low indices of complications, absence of deaths and relatively low stays in the ICU and in hospital.

To assess off-pump myocardial revascularization in patients with significant left ventricular dysfunction.Four hundred and five patients with an ejection fraction less than 35% underwent myocardial revascularization without extracorporeal circulation. The procedure was performed with the aid of a suction stabilizer and the LIMA stitch. The distal anastomoses were performed first.A total of 405 patients were evaluated whose mean age was 63.4 +/- 9.78 years. Two hundred and seventy-nine patients were men (68.8%). With regard to risk factors, 347 patients were hypertensive, 194 were smokers, 202 were dyslipidemic, and 134 had diabetes. Two hundred and sixty patients were classified as NYHA functional class III and IV. Twenty patients suffered from chronic renal disease and were under dialysis. Fifty-one underwent emergency surgery, and 33 had been previously operated on. The mean ejection fraction was 27.2 +/- 3.54%. The mean EuroSCORE was 8.46 +/- 4.41. The mean number of anastomoses performed was 3.03 +/- 1.54 per patient. Forty-nine patients (12%) needed an intra-aortic balloon inserted after induction of anesthesia, whereas 73 (18%) needed inotropic support during the perioperative period. As to complications, 2 patients (0.49%) had renal failure, 2 had mediastinitis (0.49%), 7 (1.7%) needed to be reoperated because of bleeding, 5 patients (1.2%) suffered acute myocardial infarction, and 70 patients (17.3%) experienced atrial fibrillation. Eighteen (4.4%) patients died.Based on the data above, we concluded that myocardial revascularization without extracorporeal circulation in patients with left ventricular dysfunction is a safe and effective technique, and an alternative for high-risk patients. Results obtained were better than those predicted by EuroSCORE.