Lipídios em sedimentos arqueológicos: resultados preliminares do sítio arqueológico Rio do Meio, Ilha de Santa Catarina (SC)

Este trabalho foi realizado com o objetivo de avaliar a distribuição de lipídios em sedimentos arqueológicos do sítio Rio do Meio, Ilha de Santa Catarina. Nos extratos totais de lipídios, analisados por cromatografia gasosa e espectrometria de massas (CG e CG-EM), predominaram os compostos ácidos e álcoois saturados. Foram detectados pelo menos dois tipos de matéria orgânica: uma antiga e outra comparativamente recente. Na primeira, o extrato total de lipídios foi dominado por ácidos graxos de cadeias curtas (< Ac20:0), com menor percentagem de ácidos e álcoois de cadeias longas (> Ac20:0 e Al20:0). Em contraste, na deposição classificada como recente, foram identificados em maiores teores os ácidos e álcoois de cadeias longas (> Ac20:0 e Al20:0). Neste estudo, foi possível observar a incorporação de material orgânico procedente de fontes de origem vegetal, bacteriana e, possivelmente, animal (gorduras) nos sedimentos arqueológicos analisados

Application of Solid Phase Microextraction and Gas Chromatography for the Determination of BTEX in Solid Petroleum Residues

This work describes a simple and fast method for the determination of BTEX (benzene, toluene, ethylbenzene and xylene) in solid waste and solutions obtained from leaching applying procedures detailed in the ABNT NBR 10004/2004 Brazilian standard for the classification of solid residues. The proposed method allows the direct detection of BTEX using solid-phase microextraction and gas chromatography with a flame ionization detector (HS-SPME GC/FID). Limits of quantification for BTEX showed that the developed method is suitable for the classification of solid wastes

Dynamics of oscillating erythrocyte doublets after electrofusion

AbstractErythrocytes were electrofused with multiple rectangular voltage pulses to show an oscillatory movement, divided into swell phases and pump events. During each swell phase, which lasted from 0.5s to more than 180s, the fused cells’ (doublets’) volume increased by colloid osmotic swelling, and the membrane area was expanded until rupture. Membrane rupture initiated the pump event, where the doublets’ volume and membrane area decreased with an almost exponential time course and time constants between 2ms and 8ms. Simultaneously, a portion of cytosolic hemoglobin solution was ejected into extracellular space (“jet”). Pump event time constants and swell phase durations decreased with rising chamber temperature, indicating that both parts of the oscillatory movements were determined by physical properties of membrane and liquids. Relative volume change developments express a gradual loss of membrane elasticity during the oscillation, decreasing the elastic forces stored in the membrane. Evidence is given that the first rupture causes a weakening of the membrane at the rupture site. Heat treatment up to 45°C had a negligible effect on swell times, pump time constants, and relative volume changes. A heat treatment of 50°C prevented oscillatory movements. The rupture location accorded with theories of potential induced membrane electropermeabilization

Extra-Adrenal Retroperitoneal Myelolipoma Resected by Laparoscopy in an Asymptomatic Patient

Myelolipomas are rare benign neoplasms that commonly develop in the adrenal glands. Less frequently, they can affect other organs such as the liver, stomach, liver, lung, and retroperitoneum. It affects more women, with an average age of around 61 years. Histologically, they are composed of mature adipose tissue and hematopoietic cells. With the evolution of immunohistochemistry, there are characteristics that can differentiate from malignant tumors such as liposarcomas. Its treatment remains based on surgical resection and long-term outpatient follow-up