Microhardness of a dental restorative composite resin containing nanoparticles polymerized with argon ion laser

The objective of this study was to compare the microhardness of two resin composites (microhybrid and nanoparticles). Light activation was performed with argon ion laser 1.56J (L) and halogen light 2.6J (H) was used as control. Measurements were taken on the irradiated surfaces and those opposite them, at thicknesses of 1, 2 and 3 mm. To evaluate the quality of polymerization, the percentages of maximum hardness were calculated (PMH). For statistical analysis the ANOVA and Tukey tests were used (p <= 0.05). To microhybrid was shown that the hardness with laser was inferior to the hardness achieved with halogen light, for both the 1 mm and 2 mm. The nanoparticles polymerized with laser, presented lower hardness even on the irradiated surface, than the same surface light activated with halogen light. The microhybrid attained a minimum PMH of 80% up to the thickness of 2 mm with halogen light, and with laser, only up to 1 mm. The nanoparticles attained a minimum PMH of 80% up to 3 mm thickness with halogen light and with laser this minimum was not obtained at any thickness. Based on these results, it could be concluded that light activation with argon ion laser is contra-indicated for the studied nanoparticles. Published by Elsevier GmbH.

Vorapaxar in the Secondary Prevention of Atherothrombotic Events

BACKGROUND Thrombin potently activates platelets through the protease-activated receptor PAR-1. Vorapaxar is a novel antiplatelet agent that selectively inhibits the cellular actions of thrombin through antagonism of PAR-1. METHODS We randomly assigned 26,449 patients who had a history of myocardial infarction, ischemic stroke, or peripheral arterial disease to receive vorapaxar (2.5 mg daily) or matching placebo and followed them for a median of 30 months. The primary efficacy end point was the composite of death from cardiovascular causes, myocardial infarction, or stroke. After 2 years, the data and safety monitoring board recommended discontinuation of the study treatment in patients with a history of stroke owing to the risk of intracranial hemorrhage. RESULTS At 3 years, the primary end point had occurred in 1028 patients (9.3%) in the vorapaxar group and in 1176 patients (10.5%) in the placebo group (hazard ratio for the vorapaxar group, 0.87; 95% confidence interval [CI], 0.80 to 0.94; P<0.001). Cardiovascular death, myocardial infarction, stroke, or recurrent ischemia leading to revascularization occurred in 1259 patients (11.2%) in the vorapaxar group and 1417 patients (12.4%) in the placebo group (hazard ratio, 0.88; 95% CI, 0.82 to 0.95; P=0.001). Moderate or severe bleeding occurred in 4.2% of patients who received vorapaxar and 2.5% of those who received placebo (hazard ratio, 1.66; 95% CI, 1.43 to 1.93; P<0.001). There was an increase in the rate of intracranial hemorrhage in the vorapaxar group (1.0%, vs. 0.5% in the placebo group; P<0.001). CONCLUSIONS Inhibition of PAR-1 with vorapaxar reduced the risk of cardiovascular death or ischemic events in patients with stable atherosclerosis who were receiving standard therapy. However, it increased the risk of moderate or severe bleeding, including intracranial hemorrhage. (Funded by Merck; TRA 2P-TIMI 50 ClinicalTrials.gov number, NCT00526474.)

Prediction of enzymatic infarct size in ST-segment elevation myocardial infarction

Objectives Predictors of adverse outcomes following myocardial infarction (MI) are well established; however, little is known about what predicts enzymatically estimated infarct size in patients with acute ST-elevation MI. The Complement And Reduction of INfarct size after Angioplasty or Lytics trials of pexelizumab used creatine kinase (CK)-MB area under the curve to determine infarct size in patients treated with primary percutaneous coronary intervention (PCI) or fibrinolysis. Methods Prediction of infarct size was carried out by measuring CK-MB area under the curve in patients with ST-segment elevation MI treated with reperfusion therapy from January 2000 to April 2002. Infarct size was calculated in 1622 patients (PCI=817; fibrinolysis=805). Logistic regression was used to examine the relationship between baseline demographics, total ST-segment elevation, index angiographic findings (PCI group), and binary outcome of CK-MB area under the curve greater than 3000 ng/ml. Results Large infarcts occurred in 63% (515) of the PCI group and 69% (554) of the fibrinolysis group. Independent predictors of large infarcts differed depending on mode of reperfusion. In PCI, male sex, no prior coronary revascularization and diabetes, decreased systolic blood pressure, sum of ST-segment elevation, total (angiographic) occlusion, and nonright coronary artery culprit artery were independent predictors of larger infarcts (C index=0.73). In fibrinolysis, younger age, decreased heart rate, white race, no history of arrhythmia, increased time to fibrinolytic therapy in patients treated up to 2 h after symptom onset, and sum of ST-segment elevation were independently associated with a larger infarct size (C index=0.68). Conclusion Clinical and patient data can be used to predict larger infarcts on the basis of CK-MB quantification. These models may be helpful in designing future trials and in guiding the use of novel pharmacotherapies aimed at limiting infarct size in clinical practice. Coron Artery Dis 23:118-125 (C) 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Enhancement of blood-tumor barrier permeability by Sar-[D-Phe8]des-Arg9BK, a metabolically resistant bradykinin B1 agonist, in a rat C6 glioma model

Abstract Background While it is well known that bradykinin B2 agonists increase plasma protein extravasation (PPE) in brain tumors, the bradykinin B1 agonists tested thus far are unable to produce this effect. Here we examine the effect of the selective B1 agonist bradykinin (BK) Sar-[D-Phe8]des-Arg9BK (SAR), a compound resistant to enzymatic degradation with prolonged activity on PPE in the blood circulation in the C6 rat glioma model. Results SAR administration significantly enhanced PPE in C6 rat brain glioma compared to saline or BK (p < 0.01). Pre-administration of the bradykinin B1 antagonist [Leu8]-des-Arg (100 nmol/Kg) blocked the SAR-induced PPE in the tumor area. Conclusions Our data suggest that the B1 receptor modulates PPE in the blood tumor barrier of C6 glioma. A possible role for the use of SAR in the chemotherapy of gliomas deserves further study.

Utilização de terapêuticas comprovadamente úteis no tratamento da coronariopatia aguda: comparação entre diferentes regiões brasileiras. Análise do Registro Brasileiro de Síndromes Coronarianas Agudas (BRACE - Brazilian Registry on Acute Coronary Syndromes)

FUNDAMENTO: Pouco se sabe, em nosso meio, sobre diferenças regionais no tratamento da coronariopatia aguda. OBJETIVO: Analisar o comportamento regional relativamente à utilização de terapêuticas comprovadamente úteis na coronariopatia aguda. MÉTODOS: Foram selecionados aleatoriamente 71 hospitais, respeitando-se a proporcionalidade do país em relação à localização geográfica, entre outros critérios. Na população global, foi analisada regionalmente a utilização de AAS, clopidogrel, inibidor da ECA/bloqueador de AT1, betabloqueador e estatina, isoladamente e agrupados por escore individual que variou de 0 (nenhum medicamento utilizado) a 100 (todos utilizados). No infarto com supradesnivelamento de ST (IAMCSST) foram analisadas diferenças regionais sobre utilização de terapêuticas de recanalização (fibrinolíticos e angioplastia primária). RESULTADOS: No global da população, nas primeiras 24 horas de hospitalização, a média de escore na região Norte-Nordeste (70,5 ± 22,1) foi menor (p < 0,05) do que nas regiões Sudeste (77,7 ± 29,5), Centro-Oeste (82 ± 22,1) e Sul (82,4 ± 21). Por ocasião da alta, o escore da região Norte-Nordeste (61,4 ± 32,9) foi menor (p < 0,05) do que nas regiões Sudeste (69,2 ± 31,6), Centro-Oeste (65,3 ± 33,6), e Sul (73,7 ± 28,1); adicionalmente, o escore do Centro-Oeste foi menor (p < 0,05) do que o do Sul. No IAMCSST, o uso de terapêuticas de recanalização foi maior no Sudeste (75,4%, p = 0,001 em relação ao restante do país), e menor no Norte-Nordeste (52,5%, p < 0,001 em relação ao restante do país). CONCLUSÃO: O uso de terapêuticas comprovadamente úteis no tratamento da coronariopatia aguda está aquém do desejável no país, com importantes diferenças regionais.

Reflexões sobre a influência de Maquiavel na educação e na formação do Estado Moderno

Este texto tem como objetivo analisar algumas formulações de Nicolau Maquiavel sobre a teoria política, bem como refletir sobre a contribuição de suas ideias, expostas na obra O Príncipe, para a formação do Estado Moderno Absoluto. Essa obra foi resultado de suas reflexões sobre os problemas do seu tempo: séculos XV e XVI, na Itália. O Príncipe expressava o desenvolvimento dos Estados Nacionais, a dessacralização do político, a independência do poder temporal em relação ao poder religioso e a primazia do Estado frente à religião. Consideramos que a obra de Maquiavel é de suma relevância para a história das ideias, principalmente, no campo da ciência política. Dessa forma, destacamos a importância do estudo de seu pensamento sob a perspectiva da Educação, o qual nos possibilita a compreensão dos fundamentos políticos da modernidade e, por conseguinte, o entendimento da formação do homem político-moderno.

Usable work of macro-scale cavities in liquids

It is shown that the generation of cavities in a liquid can produce usable work, which is illustrated by the stretching of a string. This work is done during the expansion of the cavity, and not with its collapse. Basic equations are presented for the movement of a device moved by the so called cavity events. A theoretical solution is also proposed, which uses polynomial functions relating the so called "excess of pressure" in the cavity and time. Evaluations of the force generated during the expansion of the cavity showed a mean peak value of about 58 N for the moving container, while measurements with the container fixed to a support showed a peak value of 476 N, considered somewhat overestimated, because high frequency oscillations seem to superpose the mean behavior. Simultaneous phenomena occurring during the cavity events are also described. Series of pictures of the experiments are presented.