Infective endocarditis in intravenous drug abusers: an update

Infective endocarditis despite advances in diagnosis remains a common cause of hospitalization, with high morbidity and mortality rates. Through literature review it is possible to conclude that polymicrobial endocarditis occurs mainly in intravenous drug abusers with predominance in the right side of the heart, often with tricuspid valve involvement. This fact can be associated with the type of drug used by the patients; therefore, knowledge of the patient's history is critical for adjustment of the therapy. It is also important to emphasize that the most common combinations of organisms in polymicrobial infective endocarditis are: Staphylococcus aureus, Streptococcus pneumonia and Pseudomonas aeruginosa, as well as mixed cultures of Candida spp. and bacteria. A better understanding of the epidemiology and associated risk factors are required in order to develop an efficient therapy, although PE studies are difficult to perform due to the rarity of cases and lack of prospective cohorts.This work was supported by Portuguese Foundation for Science and Technology (FCT) through the grants SFRH/BPD/47693/2008, SFRH/BPD/20987/2004 and SFRH/BPD/72632/2010 attributed to Claudia Sousa, Claudia Botelho and Diana Rodrigues, respectively

The use of a metronome during cardiopulmonary resuscitation in the emergency room of a university hospital

ABSTRACT Objective: to compare the rate of return of spontaneous circulation (ROSC) and death after cardiac arrest, with and without the use of a metronome during cardiopulmonary resuscitation (CPR). Method: case-control study nested in a cohort study including 285 adults who experienced cardiac arrest and received CPR in an emergency service. Data were collected using In-hospital Utstein Style. The control group (n=60) was selected by matching patients considering their neurological condition before cardiac arrest, the immediate cause, initial arrest rhythm, whether epinephrine was used, and the duration of CPR. The case group (n=51) received conventional CPR guided by a metronome set at 110 beats/min. Chi-square and likelihood ratio were used to compare ROSC rates considering p≤0.05. Results: ROSC occurred in 57.7% of the cases, though 92.8% of these patients died in the following 24 hours. No statistically significant difference was found between groups in regard to ROSC (p=0.2017) or the occurrence of death (p=0.8112). Conclusion: the outcomes of patients after cardiac arrest with and without the use of a metronome during CPR were similar and no differences were found between groups in regard to survival rates and ROSC

Robust Models for Optic Flow Coding in Natural Scenes Inspired by Insect Biology

The extraction of accurate self-motion information from the visual world is a difficult problem that has been solved very efficiently by biological organisms utilizing non-linear processing. Previous bio-inspired models for motion detection based on a correlation mechanism have been dogged by issues that arise from their sensitivity to undesired properties of the image, such as contrast, which vary widely between images. Here we present a model with multiple levels of non-linear dynamic adaptive components based directly on the known or suspected responses of neurons within the visual motion pathway of the fly brain. By testing the model under realistic high-dynamic range conditions we show that the addition of these elements makes the motion detection model robust across a large variety of images, velocities and accelerations. Furthermore the performance of the entire system is more than the incremental improvements offered by the individual components, indicating beneficial non-linear interactions between processing stages. The algorithms underlying the model can be implemented in either digital or analog hardware, including neuromorphic analog VLSI, but defy an analytical solution due to their dynamic non-linear operation. The successful application of this algorithm has applications in the development of miniature autonomous systems in defense and civilian roles, including robotics, miniature unmanned aerial vehicles and collision avoidance sensors

Ligand-Dependent Conformations and Dynamics of the Serotonin 5-HT2A Receptor Determine Its Activation and Membrane-Driven Oligomerization Properties

From computational simulations of a serotonin 2A receptor (5-HT2AR) model complexed with pharmacologically and structurally diverse ligands we identify different conformational states and dynamics adopted by the receptor bound to the full agonist 5-HT, the partial agonist LSD, and the inverse agonist Ketanserin. The results from the unbiased all-atom molecular dynamics (MD) simulations show that the three ligands affect differently the known GPCR activation elements including the toggle switch at W6.48, the changes in the ionic lock between E6.30 and R3.50 of the DRY motif in TM3, and the dynamics of the NPxxY motif in TM7. The computational results uncover a sequence of steps connecting these experimentally-identified elements of GPCR activation. The differences among the properties of the receptor molecule interacting with the ligands correlate with their distinct pharmacological properties. Combining these results with quantitative analysis of membrane deformation obtained with our new method (Mondal et al, Biophysical Journal 2011), we show that distinct conformational rearrangements produced by the three ligands also elicit different responses in the surrounding membrane. The differential reorganization of the receptor environment is reflected in (i)-the involvement of cholesterol in the activation of the 5-HT2AR, and (ii)-different extents and patterns of membrane deformations. These findings are discussed in the context of their likely functional consequences and a predicted mechanism of ligand-specific GPCR oligomerization

Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p

Investigation on the effects of guava (Psidium guajava L.) infusions on germination, root tips and meristematic cells of Latuca sativa

Guava (Psidium guajava L.) is a plant often employed in popular medicine. Recently several studies have alerted about the toxicity of substances present in medicinal plants, which can pose risks to the human health. In this sense, the present work aimed to investigate the phytotoxic, cytotoxic and genotoxic action of three guava varieties - Paluma, Pedro Sato and Roxa (purple) - on the plant test system Lactuca sativa L. Thus, macro- and microscopic evaluations were carried out for five infusion concentrations (2.5, 5.0, 10.0, 20.0 and 40.0 g.L-1) prepared from each variety. Distilled water was used as negative control. Chromatographic and spectroscopic analysis by HPLC-PAD indicated that the chemical composition of the infusion of Roxa is different than that of the infusions of the varieties Paluma and Pedro Sato. It was observed that seed germination and root growth in L. sativa exposed to infusions decreased with increasing infusion concentration, regardless of the tested cultivar. For the mitotic index, no statistical differences were observed. On the other hand, a significant increase in the frequency of cell cycle alterations was verified, especially for the highest concentrations tested. The cytogenotoxic was significant. Therefore, guava should not be used indiscriminately in popular medicine.A goiaba (Psidium guajava L.) é uma planta bastante utilizada na medicina popular. Recentemente alguns trabalhos tem alertado acerca da toxicidade de substâncias presentes em plantas medicinais, o que pode trazer riscos à saúde humana. Neste sentido, o presente trabalho objetivou investigar a ação fitotóxica, citotóxica e genotóxica de três variedades de goiaba - Paluma, Pedro Sato e Roxa - no sistema teste vegetal Lactuca sativa L. Assim, foram realizadas avaliações macro- e microscópicas para cinco concentrações de infusões (2,5, 5,0, 10,0, 20,0 e 40,0 g.L-1) preparadas a partir de cada variedade. A água destilada foi usada como controle negativo. As análises cromatográficas e espectroscópicas por HPLC-PAD indicaram que a composição química da infusão da Roxa é diferente das infusões das variedades Paluma e Pedro Sato. Foi observado que a germinação das sementes e o crescimento da raiz em L. sativa expostas às infusões diminuem com o aumento da concentração da infusão, independentemente da cultivar testada. Para o índice mitótico, diferenças estatísticas não foram observadas. Por outro lado, foi verificado um aumento significativo na frequência de alterações do ciclo celular, especialmente para as maiores concentrações testadas. O efeito citogenotóxico foi significativo. Portanto, a goiaba não deve ser utilizada indiscriminadamente na medicina popular.Universidade Federal do Espírito Santo Centro de Ciências Agrárias Departamento de BiologiaUniversidade Federal de Lavras Departamento de BiologiaUniversidade Estadual Paulista Faculdade de Ciências Departamento de QuímicaUniversidade Estadual Paulista Faculdade de Ciências Departamento de Químic