Introducción: La intervención coronaria percutánea primaria durante las 24 primeras horas de inicio del dolor torácico reduce la mortalidad por infarto de miocardio con ST elevado (IMA STE). El objetivo del estudio fue evaluar la mortalidad intrahospitalaria a 30 días según el tiempo puerta-balón y el tiempo total de isquemia en pacientes con IAM STE sometidos a intervención coronaria percutánea (ICP) primaria en un hospital de referencia. Métodos: Estudio retrospectivo de cohorte de pacientes con IMA STE sometidos a ICP primaria en un hospital de referencia de Lima, Perú. Analizamos la asociación entre el tiempo total de isquemia menor a 12 horas y tiempo puerta balón menor a 90 minutos con mortalidad a 30 días, mediante Regresión de Cox, ajustado por otros factores. Resultados: Durante el periodo 2010-2014, 296 sujetos con IMA STE fueron sometidos a ICP primaria. El 82,4% fueron varones y la media de edad fue 66,5 años ±11,8. La mortalidad intrahospitalaria a 30 días fue 8,11%. El 82,43% tuvo un tiempo total de isquemia menor a 12 horas y el 33,11% un tiempo puerta-balón menor a 90 minutos. No se encontró asociación entre ambos tiempos y mortalidad intrahospitalaria. El paro cardiaco (HR: 2,9 IC 95% 1,09-7,72), shock cardiogénico al ingreso (HR: 7,06 IC 95% 2,84-17,59) y un flujo TIMI menor a 3 post ICP (HR: 4,21 IC 95% 1,73-10,19) se asociaban a mayor mortalidad. Conclusión: No hubo asociación entre los tiempos estudiados con la mortalidad intrahospitalaria. Se sugieren intervenciones para disminuir los tiempos en esta población. / Introduction: Primary percutaneous coronary intervention reduces mortality in patients with ST elevated myocardial infarction (STE MI). The objective was to evaluate the 30 days in-hospital mortality according to door-to-balloon time and total ischemic time in patients treated with primary PCI. Methods: A retrospective cohort study was performed including patients with STE MI who underwent primary PCI at a national reference hospital in Lima, Peru. A Cox Regression analysis was performed for door-to-balloon time less than 90 minutes and total ischemic time less than 12 hours as predictors and in-hospital mortality as outcome. Results: During 2010’2014, 296 STE MI patients underewent PCI. From them, 82,4% were male. The mean age was 66,5 ±11,8 years. The 30-day mortality was 8,11%. The proportion of patients with total ischemic time less than 12 hours and door-to-balloon time was 82,43% and 33,11% respectively. No association between these intervals and 30-day mortality was found. Cardiac arrest (HR: 2,9 95%CI 1,09-7,72), cardiogenic shock at the admission (HR: 7,06; 95%CI: 2,84- 17,59) and TIMI flow less than 3 after primary PCI (HR: 4,21; 95%CI: 1,73-10,19) were associated with higher 30-day mortality.. Conclusion: No association between mortality and lower total ischemia time or door to ballon time mortality was found. A significant delay was observed in hospital arrival and performing revascularization.

Iron deficiency (ID) is especially common in pregnant women and may even persist following childbirth. This is of concern in light of reports demonstrating that ID may be sufficient to produce homeostatic dysregulation of other metals, including manganese (Mn). These results are particularly important considering the potential introduction of the Mn-containing gas additive, methyl cyclopentadienyl manganese tricarbonyl (MMT), in various countries around the world. In order to model this potentially vulnerable population, we fed female rats fed either control (35 mg Fe/kg chow; 10 mg Mn/kg chow) or low iron/high-manganese (IDMn; 3.5 mg Fe/kg chow; 100 mg Mn/kg chow) diet, and examined whether these changes had any long-term behavioral effects on the animals' spatial abilities, as tested by the Morris water maze (MWM). We also analyzed behavioral performance on auditory sensorimotor gating utilizing prepulse inhibition (PPI), which may be related to overall cognitive performance. Furthermore, brain and blood metal levels were assessed, as well as regional brain isoprostane production. We found that treated animals were slightly ID, with statistically significant increases in both iron (Fe) and Mn in the hippocampus, but statistically significantly less Fe in the cerebellum. Additionally, isoprostane levels, markers of oxidative stress, were increased in the brain stem of IDMn animals. Although treated animals were indistinguishable from controls in the PPI experiments, they performed less well than controls in the MWM. Taken together, our data suggest that vulnerable ID populations exposed to high levels of Mn may indeed be at risk of potentially dangerous alterations in brain metal levels which could also lead to behavioral deficits.

A substance that cross-reacts with antiserum to human atrial natriuretic peptide (ANP) is found in fish hearts. This ANP-like material increases sodium output from the gill and kidney while inhibiting sodium uptake in the gut. Mammalian ANP secretion is stimulated by glucocorticoids, and cortisol injection increases sodium output in salt-loaded fish. Therefore, we wanted to determine if the release of ANP in fish is sensitive to dexamethasone. Ventricle cardiocytes from the rainbow trout Oncorhynchus mykiss were treated with various doses of dexamethasone for 18 or 72 h. Single ventricle cells were then assayed for ANP release using a reverse hemolytic plaque assay and antiserum to human alpha-ANP. Incubation with 100 microM dexamethasone almost doubled the population of ventricle cells committed to ANP release (basal, 15.0 +/- 0.3% vs. Dexamethasone, 28.3 +/- 1.4%; values are percent plaque formation +/- SE). Stimulation of ANP secretion was dependent on dose and time of exposure to dexamethasone. These results suggest that ANP secretion in fish is regulated by glucocorticoids.

OBJECTIVE: To determine if laser-assisted anastomosis is superior to microsurgical anastomosis and laser welding for tubal reconstruction. STUDY DESIGN: Sixty uterine tubes from 30 rabbits were transected and then anastomosed with a microsurgical technique, laser welding and laser-assisted anastomosis using a microscope. The rabbits were mated one month postoperatively and examined for implantation sites and adhesion formation three to seven days postpartum. RESULTS: The amount of time required to perform laser-assisted anastomosis as well as laser welding was significantly shorter than for microsurgery. All the tubes withstood the distension pressure of pregnancy with the exception of 1 of the 20 laser-welded tubes, which had 30% of its circumference dehisced. There was no difference in the number of implantation sites per tube between the different groups. The anastomotic sites were well healed and were nonidentifiable except for holding stitches and microsurgical sutures. CONCLUSION: Laser-assisted anastomosis and laser welding took less time to perform than microsurgery. Laser-assisted anastomosis resulted in excellent healing, as did microsurgery. With the protection of serum albumin, laser-assisted anastomosis did not cause any thermal damage, and the anastomotic sites could tolerate the distension pressure of pregnancy and parturition without problems. Laser welding without protection of serum albumin could cause thermal damage and dehiscence. The implantation and pregnancy rates were comparable The implantation and pregnancy rates were comparable with all three types of procedure.

OBJECTIVES: Despite numerous studies in which various methods for arteriotomy closure after carotid endarterectomy (CEA) have been addressed, the optimum surgical technique to reduce complications and late carotid restenosis has yet to be firmly established. The purpose of this study was to prospectively compare the results of the eversion CEA technique with those of conventional CEA with either primary closure or carotid patch angioplasty, and to determine under clinical conditions whether eversion CEA influences the results and restenosis rate. PATIENTS AND METHODS: Over a 3-year period, 322 CEAs performed on 296 consecutive patients were concurrently evaluated. This study included 118 eversion CEAs, 97 CEAs with primary closure, and 107 CEAs with patch angioplasty. There were no differences in demographics, in surgical indications, or in the severity of carotid disease (not significant [NS]). The choice of CEA technique was not randomized because of technical considerations and surgeon preference. After entry into the protocol, no patients were excluded or withdrawn. Carotid restenosis was defined as a > 60% lumen reduction at the CEA site with established duplex ultrasonography criteria. RESULTS: The mean operative time for eversion CEA was 31 minutes, for CEA-primary closure it was 39 minutes, and for CEA-patch angioplasty it was 46 minutes (P <.01). The operative mortality rate for eversion CEA was 0.8% (1 patient), for CEA-primary closure it was 1.0% (1 patient), and for CEA-patch angioplasty it was 2.8% (3 patients) (NS). The postoperative stroke rate was 0.8% after eversion CEA, 1.0% after CEA-primary closure, and 2.8% after CEA-patch angioplasty (NS). The combined stroke and death rate in each group was thus 0.8% for eversion CEA (1 stroke-death), 1% for CEA with primary closure (1 stroke-death), and 5% for CEA with patch angioplasty (1 stroke-death, 2 fatal myocardial infarctions, and 2 nonfatal strokes) (NS). Transient ischemic attacks occurred in 2.5% after eversion CEA, in 5.2% after CEA-primary closure, and in 2.9% with CEA-patch angioplasty (NS). The mean clinical follow-up for all three groups was 23 months (range, 6-42 months) (NS). The restenosis rate was 1.7% after eversion CEA, 9.3% after CEA-primary closure, and 6.5% after CEA-patch angioplasty (P <.05). CONCLUSIONS: This prospective, nonrandomized clinical study indicates that eversion CEA is an effective surgical option comparable to conventional CEA with either primary arteriotomy closure or carotid patch angioplasty. No differences were found between eversion CEA and these more widely accepted CEA closure techniques with respect to operative morbidity and mortality. These data indicate, however, that eversion CEA has a lower restenosis rate than conventional CEA closure techniques and thus superior long-term durability.

No / The influence of loose plant leaves on the acoustic absorption of a porous substrate is experimentally and numerically studied. Such systems are typical in vegetative walls, where the substrate has strong acoustical absorbing properties. Both experiments in an impedance tube and theoretical predictions show that when a leaf is placed in front of such a porous substrate, its absorption characteristics markedly change (for normal incident sound). Typically, there is an unaffected change in the low frequency absorption coefficient (below 250 Hz), an increase in the middle frequency absorption coefficient (500-2000 Hz) and a decrease in the absorption at higher frequencies. The influence of leaves becomes most pronounced when the substrate has a low mass density. A combination of the Biot's elastic frame porous model, viscous damping in the leaf boundary layers and plate vibration theory is implemented via a finite-difference time-domain model, which is able to predict accurately the absorption spectrum of a leaf above a porous substrate system. The change in the absorption spectrum caused by the leaf vibration can be modeled reasonably well assuming the leaf and porous substrate properties are uniform.

BACKGROUND: Centres in Phases I and III of the International Study of Asthma and Allergies in Childhood (ISAAC) programme used the method of consent (passive or active) required by local ethics committees. METHODS: Retrospectively, relationships between achieved response rates and method of consent for 13-14 and 6-7-year-olds (adolescents and children, respectively), were examined between phases and between English and non-English language centres. RESULTS: Information was obtained for 113 of 115 centres for adolescents and 72/72 centres for children. Both age groups: most centres using passive consent achieved high response rates (>80% adolescents and >70% children). English language centres using active consent showed a larger decrease in response rate. Adolescents: seven centres changed from passive consent in Phase I to active consent in Phase III (median decrease of 13%), with five centres showing lower response rates (as low as 34%). Children: no centre changed consent method between phases. Centres using active consent had lower median response rates (lowest response rate 45%). CONCLUSION: The requirement for active consent for population school-based questionnaire studies can impact negatively on response rates, particularly English language centres, thus adversely affecting the validity of the data. Ethics committees need to consider this issue carefully. / Revisión por pares

A autora se propõe a fazer uma avaliação qualitativa dos trabalhos publicados de 1998 a 2002, nas Revistas The Journal of Bone and Joint Surgery (JBJS) e Revista Brasileira de Ortopedia (RBO). Após o levantamento da literatura foram classificados os trabalhos por qualidade metodológica e foram listados por ordem cronológica. Os trabalhos foram lidos e classificados nas duas revistas, checados por mais um avaliador além da autora e classificados segundo os níveis previstos no projeto diretrizes AMB/CFM. Como resultado observou-se, pela avaliação das tabelas com análise estatística que, nos primeiros anos predominavam os artigos de nível C e D na RBO, enquanto no JBJS os artigos eram distribuídos eqüitativamente entre todos os níveis. No ano de 2002, ambas as revistas aumentaram o percentual de artigos de nível A. Os resultados foram comentados face à literatura consultada. A autora concluiu que a RBO e o JBJS mostraram perfis diferentes de publicação no período analisado, apresentando, no entanto tendência a melhora metodológica em ambas as publicações, e que os resultados indicam a necessidade da divulgação dos critérios de excelência metodológica entre autores e profissionais da saúde em nosso meio. Em anexos foram identificados termos que são usualmente empregados em epidemiologia e metodologia científica, bem como definidos os níveis de evidência considerados nos quais foram distribuídos os trabalhos analisados. / The authors proposes to do a qualitative valuation for published articles from 1998 to 2002, in magazines The Journal of Bone and Joint Surgery Am and Brazilian Orthopaedic Magazine. After searching in literature, the articles were classified according to methodological quality and they were organized by chronological order. The articles of two magazines were read, classified and checked by the authoress and another valuator due to the levels in Directive Project. As result, by valuation of tables with statistical analysis, in first years the articles of level C and D were predominant in Brazilian Orthopaedic Magazine, in JBJS the articles were separeted equitably among all levels. In 2002, both magazines increased the percentual of level A articles. The authoress concluded that two magazines presented different aspects of publication in that period of time, however both publications have showed methodological improvement. The results also showed that the standards of methodological excellence must be known among authors and health profissionals. Terms which are frequently used in epidemiology and scientific methodology were identified in annexed and the levels of evidence of analysed articles were defined.

Os objetivos do estudo foram avaliar as características clínicas das embolias arteriais sistêmicas no curso da endocardite infecciosa, a distribuição temporal, os fatores de risco de embolia e a influência prognóstica da embolia no curso da doença. Foram estudados 629 episódios de endocardite infecciosa. A idade dos pacientes variou de 2 meses a 83 anos (média 37,9 anos; desvio padrão 17,3). Ocorreram 396 (63%) episódios em homens e 233 (47%) em mulheres. Em 538 (85%) episódios, os pacientes eram portadores de doença cardíaca prévia, 272 (43%) com valvopatia, 224 (36%) portadores de prótese valvar cardíaca, 29 (5%) com doença cardíaca congênita, 13 (2%) com outras cardiopatias e 91 (14%) pacientes não apresentavam evidência de cardiopatia prévia. Os agentes etiológicos foram os estreptococos em 297 (47%) pacientes, os enterococos em 51 (8%), os Staphylococcus aureus em 77 (12,6%), os Staphylococcus epidermidis em 56 (9%), as bactérias gram-negativas em 33 (5%), os fungos em nove (1,4%), e outros microorganismos em 27 (4%). Em 79 (13%) pacientes as hemoculturas foram negativas. Os pacientes receberam tratamento clínico em 376 (60%) episódios e cirúrgico em 253 (40%). Para a análise estatística foram utilizados além da estatística descritiva, o método de Kaplan-Meier para avaliar a sobrevida livre de embolia e o prognóstico, comparadas com os testes de Log-rank e Breslow. Em seguida para a estimativa de riscos, foi ajustado o modelo de riscos proporcionais de Cox. As embolias arteriais ocorreram em 133 (21%) pacientes, cerebrais em 63 (47%), extracerebrais em 57 (43%) e cerebrais a extracerebrais em 13 (10%) pacientes. A distribuição temporal das embolias foi decrescente após o início dos sintomas. O risco de embolia não revelou diferença significativa quanto a idade, a sexo, o estado cardíaco, presença e número de vegetações identificadas no ecocardiograma e a modalidade de tratamento clínico ou cirúrgico. Os pacientes com endocardite causada por Staphylococcus aureus apresentaram risco de ocorrência de embolia 2,9 vezes maior do que os pacientes com endocardite causada por outros agentes etiológicos. Nos pacientes com endocardite infecciosa em prótese mitral e aórtica com vegetação identificada no ecocardiograma, o risco de embolia foi respectivamente 2,4 e 3,3 vezes maior relação aos pacientes com endocardite em valva natural ou em prótese sem vegetação. O risco de embolia foi menor a medida que o tempo decorrido entre o início dos sintomas e o tratamento aumentou. O risco de óbito nos pacientes que sofreram embolia duplicou em relação aos pacientes que não sofreram embolia. / The objectives of the study were to evaluate the clinical characteristics of systemic arterial embolism at infective endocarditis courses, the time related distribution of emboli, risk predictors and prognostic influence of emboli during active disease. So far, we studied 629 episodes of left-sided endocarditis. The patients were aged 37.9 ± 17.3 years; 396 (63%) episodes occurred in men; 233 (47%) in women; 538 (85%) episodes occurred in patients with heart disease: 272 (43%) had valvular heart disease, 224 (36%) had prosthetic heart valves, 29 (5%) had congenital heart disease, 13 (2%) had others cardiac diseases and 91 (14%) had no known heart disease. The causative microorganisms were streptococci in 297 (47%) patients, enterococci in 51 (8%), Staphylococcus aureus in 77 (1 2.6%), Sfaphylococcus epidermidis in 56 (9%), gram-negative bacteria in 33 (5%), fungi in nine (1.4%), and other microorganisms in 27 (4%); 79 (13%) patients had negative blood cultures. The treatment was medical in 376 (60%) and surgical in 253 (40%) episodes. Statistical analysis was pet-formed with descriptive analysis, with Kaplan-Meier methods to evaluate survival free of emboli and prognosis, and Cox proportional hazards model for risk analysis; 133 (21%) patients had an embolic event; 63 (47%) were cerebral emboli and 57 (43%) were extracerebral emboli and 13 (10%) were cerebral and extracerebral. The time-related distribution showed decrease in the incidence after beginning of symptoms. The risk for emboli was not significantly different relative to age, sex, cardiac status, presence or number of vegetations at echocardiogram, and medical or surgical treatment. The risk of emboli was 2.97 times higher in patients with Staphylacoccus aureus endocarditis. The risk of embolism in patients with infective endocarditis in mitral and aortic prosthetic valve with vegetations were 2.4 and 3.3 times higher. The risk of embolism decrease as the time elapsed between beginning of symptoms and treatment increased, suggesting a lower risk in less acute disease. Risk of death was 2.01 times higher in patients with embolism.

Many epidemiological studies assess the effects of time-dependent exposures, where both the exposure status and its intensity vary over time. The analysis of such studies poses the challenge of modelling the association between complex time-dependent drug exposure and the risk, especially given the uncertainty about the etiological relevance of doses taken in different time periods. / To address this challenge, I developed a flexible method for modelling cumulative effects of time-varying exposures, weighted by recency, represented by time-dependent covariates in the Cox proportional hazards model. The function that assigns weights to doses taken in the past is estimated using cubic regression splines. Models with different number of knots and constraints are estimated. Bootstrap techniques are used to obtain pointwise confidence bands around the weight functions, accounting for both the sampling variation of the regression coefficients, and the uncertainty at the model selection stage, i.e. the additional variance due to a posteriori selection of the number of knots. / To assess the method in simulations, I had to develop and validate a novel algorithm to generate event times conditional on time-dependent covariates and compared it with the algorithms available in the literature. The proposed algorithm extends a previously proposed permutational algorithm to include a rejection sampler. While all the algorithms generated data sets that, once analyzed, provided virtually unbiased estimates with comparable variances, the algorithm that I proposed reduced the computational time by more than 50 per cent relative to alternative methods. I used simulations to systematically investigate the properties of the weighted cumulative dose method. Six different weight functions were considered. Simulations showed that in most situations, the proposed method was able to capture the shape of the true weight functions and to produce estimates of the magnitude of the exposure effect on the risk that were close to those used to generate the data. I finally illustrated the use of the weighted cumulative dose modelling by reassessing the association between the use of selected benzodiazepines and fall-related injuries, using administrative data on a cohort of elderly who initiated their use of benzodiazepines between 1990 and 2004.