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Background: There are limited data about the influence of stent composition on immune responses after percutaneous coronary intervention (PCI). Objective: The aim was to compare the effects of PCI with conventional cobalt-chromium bare metal stent (BMS) and drug-eluting stent (DES) implantation on the modulation of humoral and cellular immune responses. Methods: A randomised, single-centre, open pilot study involving patients with stable coronary artery disease eligible for PCI was performed. Blood samples were collected from the peripheral artery (PA) and the coronary sinus (CS) at baseline and 40 weeks following PCI. IgM and IgG autoantibodies (Abs), anti-oxLDL and anti-ApoB-D, as well as cytokine levels were evaluated by enzyme-linked immunosorbent assay. Results: A total of 30 patients of 60 years mean age were included, 68% of whom were men. At the nine-month follow-up, a modulation in the levels of cytokines and autoantibodies was observed in both stent type groups. However, no difference was observed in the modulation of these markers between stents. Conclusion: The stent type promotes modulations in cellular and humoral immune responses in the long-term, with differences in the magnitude of effects in specific immune responses.

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Popgraphene (PopG) is a new 2D planar carbon allotrope which is composed of 5-8-5 carbon rings. PopG is intrinsically metallic and possesses excellent thermal and mechanical stability. In this work, we report a detailed study of the thermal effects on the mechanical properties of PopG membranes using fully-atomistic reactive (ReaxFF) molecular dynamics simulations. Our results showed that PopG presents very distinct fracture mechanisms depending on the temperature and direction of the applied stretching. The main fracture dynamics trends are temperature independent and exhibit an abrupt rupture followed by fast crack propagation. The reason for this anisotropy is due to the fact that y-direction stretching leads to a deformation in the shape of the rings that cause the breaking of bonds in the pentagon-octagon and pentagon-pentagon ring connections, which is not observed for the x-direction. PopG is less stiff than graphene membranes, but the Young's modulus value is only 15 % smaller.

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Carbon nanostructures are promising ballistic protection materials, due to their low density and excellent mechanical properties. Recent experimental and computational investigations on the behavior of graphene under impact conditions revealed exceptional energy absorption properties as well. However, the reported numerical and experimental values differ by an order of magnitude. In this work, we combined numerical and analytical modeling to address this issue. In the numerical part, we employed reactive molecular dynamics to carry out ballistic tests on single, double, and triple-layered graphene sheets. We used velocity values within the range tested in experiments. Our numerical and the experimental results were used to determine parameters for a scaling law. We find that the specific penetration energy decreases as the number of layers (N) increases, from ∼15 MJ/kg for N = 1 to ∼0.9 MJ/kg for N = 350, for an impact velocity of 900 m/s. These values are in good agreement with simulations and experiments, within the entire range of N values for which data is presently available. Scale effects explain the apparent discrepancy between simulations and experiments.

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Reversed-phase high-performance liquid chromatography (RP-HPLC) has been used to analyze Interferon α-2 (IFN-α2) as a pure protein or as a pharmaceutical preparation: a method for analyzing periplasmic IFN-α2 directly in osmotic shock extract has, however, never been reported. This work describes an RP-HPLC methodology for the qualitative and quantitative analysis of human IFN-α2a and IFN-α2b directly in bacterial periplasmic extracts or in purified preparations. The analytical method has been set up and validated for accuracy, precision, linearity, sensitivity and specificity. A recovery test indicated an average bias of ∼1%, intra-day and inter-day quantitative determinations presented relative standard deviations always≤5%, while the working sensitivity was of ∼0.3µg of IFN-α2 (RSD=5%). The method proved to be suitable for detecting and quantifying also glycosylated and oxidized forms and N-methionylated IFN-α2 molecules, it was, however, not able to distinguish between IFN-α2a and IFN-α2b. This rapid methodology allows the application of RP-HPLC as a powerful tool to monitor the production yield and quality of IFN-α2 in osmotic shock fluids, right after, or even during the fermentation process.

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JUSTIFICATIVA E OBJETIVOS: A doença oncológica per se é uma condição que muitas vezes influencia no tratamento dispensado ao paciente. O objetivo do presente estudo foi comparar o desfecho hospitalar de pacientes oncológicos e não oncológicos submetidos à procedimentos cirúrgicos eletivos com alto risco de óbito. MÉTODO: Estudo de coorte prospectivo observacional, realizado em UTI de hospital terciário no período de 01 de abril a 31 de julho de 2005. Foram coletados dados demográficos, escore APACHE II, MODS, variáveis hemodinâmicas, laboratoriais e avaliadas complicações definidas como re-operação, necessidade de ventilação mecânica, transfusão sangüínea e uso de cateter de artéria pulmonar no pós-operatório desses pacientes. Todos foram acompanhados até alta ou o óbito hospitalar. Para variáveis numéricas foi utilizado o teste t de Student e Mann-Whitney, para variáveis categóricas o teste do Qui-quadrado sendo considerado significativo o valor de p < 0,05. RESULTADOS: Foram incluídos no estudo 119 pacientes, 43 não oncológicos e 76 oncológicos, 52,9 por cento eram do sexo feminino. A média de idade foi 65,1 ± 14,1 anos, o escore médio de APACHE II 16,5 ± 5,8 e a mediana do MODS de 3 (2-6). A duração mediana da intervenção cirúrgica foi de 5 (3,3-7) horas e a mortalidade na UTI e hospitalar foram 10,9 por cento e 25,2 por cento, respectivamente. Os pacientes oncológicos apresentaram maiores tempos de internação hospitalar e de internação antes da cirurgia, sendo estes resultados estatisticamente significativos. A mortalidade hospitalar dos pacientes oncológicos não foi superior a dos pacientes sem neoplasia (22,4 por cento versus 30,2 por cento, p = 0,32). CONCLUSÕES: Nesta observação os pacientes oncológicos, submetidos à procedimentos cirúrgicos de alto risco, apresentaram mortalidade semelhante aos pacientes não oncológicos com gravidade de doença similar.

BACKGROUND AND OBJECTIVES: Oncologic diseases are conditions that have influence in the treatment offered to affected patients. The aim of this study was to compare hospitalar outcome of oncologic and non oncologic patients submitted to high risk elective surgery. METHODS: Prospective, observational cohort study realized in an ICU of a tertiary hospital during the period between 04/01/2005 and 07/31/2005. Demographic data, APACHE II and MODS scores and laboratorial and hemodynamic variables were collected and complications like re-intervention need for mechanical ventilation, red blood cell transfusions and pulmonary artery catheter use during the post-operative period were evaluated. All patients were followed until hospital discharge or death. T student and Mann Whitney tests were used to compare numerical variables. Chi-square test was used to compare categorical variables. A p < 0.05 was considered as significant. RESULTS: 119 patients were included in the study. 43 were oncologic and 76 were non-oncologic. 52.9 percent were female. Mean age was 65.1 ± 14.1 years. Mean APACHE II score was 16.5 ± 5.8 and MODS median was 3 (2-6). Median length of surgery was 5 (3.3-7) hours and ICU and hospital mortality were 10.9 percent and 25.2 percent, respectively. Oncologic patients had greater length of hospital stay and length of stay before surgery. These results were statistically significant. Hospital mortality of oncologic patients was not greater than non-oncologic patients (22.4 percent versus 30.2 percent, p = 0.32). CONCLUSIONS: In this series, oncologic patients submitted to high risk surgery had the same mortality rate as non-onconlogic patients with similar disease severity.

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BACKGROUND AND OBJECTIVES: Oncologic diseases are conditions that have influence in the treatment offered to affected patients. The aim of this study was to compare hospitalar outcome of oncologic and non oncologic patients submitted to high risk elective surgery. METHODS: Prospective, observational cohort study realized in an ICU of a tertiary hospital during the period between 04/01/2005 and 07/31/2005. Demographic data, APACHE II and MODS scores and laboratorial and hemodynamic variables were collected and complications like re-intervention need for mechanical ventilation, red blood cell transfusions and pulmonary artery catheter use during the post-operative period were evaluated. All patients were followed until hospital discharge or death. T student and Mann Whitney tests were used to compare numerical variables. Chi-square test was used to compare categorical variables. A p < 0.05 was considered as significant. RESULTS: 119 patients were included in the study. 43 were oncologic and 76 were non-oncologic. 52.9% were female. Mean age was 65.1 ± 14.1 years. Mean APACHE II score was 16.5 ± 5.8 and MODS median was 3 (2-6). Median length of surgery was 5 (3.3-7) hours and ICU and hospital mortality were 10.9% and 25.2%, respectively. Oncologic patients had greater length of hospital stay and length of stay before surgery. These results were statistically significant. Hospital mortality of oncologic patients was not greater than non-oncologic patients (22.4% versus 30.2%, p = 0.32). CONCLUSIONS: In this series, oncologic patients submitted to high risk surgery had the same mortality rate as non-onconlogic patients with similar disease severity.