211 research outputs found

    Ultrasound-assisted lipolysis of the omentum in dwarf pigs.

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    Successful surgical treatment of medium degree obesity by subcutaneous liposuction has been reported in the literature. In obesity, most adipose tissue is visceral, mainly omental, and the resection of omentum is a mutilating procedure for the intestinal tract. Because of this, we planned to reduce omental adipose tissue by an apparently conservative approach: ultrasound-assisted lipolysis. The purpose of this study was to assess the feasibility and safety of this procedure in an animal experimental model, drawing clinical and autoptic patterns. We chose pigs because they are functionally analogous to humans, although they store less fat in the omentum, whose structure looks like a veil. Four male dwarf pigs were fed, since weaning, with hyperlipidic fodder. When they were eight months old, they were operated on under general anesthesia in our laboratory for experimental surgery. After laparotomy, the omentum was delivered and treated with ultrasound for 1 hour. Before and just after the sonication, biopsies were drawn from omentum and processed for histologic findings. After 50 days, the surviving animals were sacrificed and autopsied; specimens from omentum, liver, and spleen were histologically processed. Two animals died during the operation, while the two surviving animals were in good general condition. Macro and microscopic observations demonstrated that the ultrasound can liquefy omental fat, sparing its fibrous network in the immediate time; during the postoperative period, an intense inflammatory reaction developed; macroscopic observation evidenced fibrous adhesions of the omentum to the surrounding organs; the connective tissue network was thickened and the whole omentum was twisted on itself. The high mortality rate could be due either to the surgical learning curve or to casualty or to lethal effects of ultrasound on the cardiac conductive system; the inflammatory peritoneal reaction could be specifically due to ultrasound or to surgical handling

    High Density Polyethylene Composites Containing Alumina-Toughened Zirconia Particles: Mechanical and Tribological Behavior

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    Alumina-toughened Zirconia (ATZ) was used as filler to endow High Density Polyethylene (HDPE) with enhanced mechanical and wear properties, hence widening the application field of the polyolefin as biomaterial. Composites at different ATZ loadings were produced by melt extrusion followed by compression molding. A good filler dispersion was obtained for all the materials, despite the presence of few voids and agglomerates observed at high ATZ loadings. The combination of high crystallinity and, mainly, lack of voids and agglomerates, appeared responsible for the improvement of Young modulus and mechanical strength. Besides, the filler positively affected the wear resistance of the composites under lubricated conditions

    Electron-Beam-Induced Grafting Of Chitosan Onto HDPE/ATZ Composites for Biomedical Applications

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    HDPE and HDPE/ATZ surfaces were functionalised with chitosan Via electron-beam irradiation technique in order to prepare materials suitable for biomedical purposes. ATR–FTIR and wettability measurements were employed for monitoring the surface changes after both irradiation and chitosan grafting reaction. The presence of ATZ influenced both the EB irradiation process and the surface functionalisation. Mechanical properties of irradiated materials were not remarkably affected by irradiation processing. Biological assays indicated that electrostatic interactions between the negative charges of the surface of cell membranes and the –NH3+ sites on chitosan chains promoted cell adhesion, while some oxidized species produced during the irradiation process were thought to cause a detrimental effect on the cell Viability

    Influence of chitosan on the mechanical and biological properties of HDPE for biomedical applications

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    High density polyethylene (HDPE) is widely used in biomedical field, except when strong cell-material interactions and high mechanical properties are required. To address this pitfall, two kinds of chitosan in different amounts were used as filler in the present research. Composites were prepared by melt extrusion process and their microstructural, thermal and mechanical properties were widely investigated. Also roughness and wettability were studied, as features of paramount importance in dictating cell response. Both types of chitosan endowed HDPE with higher Young modulus and lower elongation at break. Interestingly, fibroblast adhesion and viability were enhanced when a low amount of filler was used. The interaction of HDPE/chitosan composites with biological environment was investigated for the first time in order to assess the feasibility of these composites as materials for biomedical application

    Urban air pollution, climate and its impact on asthma morbidity

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    AbstractObjectiveTo study the mechanism of formation of air quality and to determine the impact of the studied factors on asthma morbidity in Vladivostok.MethodsThe evaluation of air pollution in Vladivostok was done using long-term (2008–2012) monitoring data (temperature, humidity, atmospheric pressure, wind speed, etc.). The levels of suspended particulate matter, nitrogen and sulfur dioxide, carbon monoxide, ammonia, formaldehyde (mg/m3) in six stationary observation posts were assessed. We studied the aerosol suspensions of solid particles, which were collected during snowfall from precipitation (snow) and air in 14 districts with different levels of anthropogenic impact. Melted snow was analyzed on laser granulometry. The impact of air pollution on the distribution of asthma morbidity was evaluated in various age groups by data of federal statistical observation obtained from 8 adults and 7 children municipal clinics in Vladivostok (2008–2012).ResultsThe content of suspended particulate components of pollution remained more stable, due to the features of atmospheric circulation, rugged terrain and residential development. The nano- and micro-sized particles (0–50 μm), which can absorb highly toxic metals, prevail in dust aerosols. These respirable fractions of particles, even in small doses, can contribute to the increase in asthma morbidity in the city.ConclusionsWe determined that asthma morbidity depends from general air pollution (in the range of 18.3%). It was detected that the highest age-specific dependence is associated with the content of particulate matter, carbon monoxide and nitrogen dioxide in air

    Il progetto “ceraNEApolis”: un sistema informativo cartografico delle produzioni ceramiche a Neapolis (IV a.C.-VII d.C.)

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    In the last few decades, urban archaeology in Naples has contributed to outline the history of the city. The discovery of a great amount of pottery gave information about the daily life of ancient Naples. It was therefore decided to draw up a thematic archaeological map of the ceramics finds to reconstruct their production and distribution from the 4th century B.C. to the 7th century A.D. The project ceraNEApolis consists of a pottery map linked to a bibliographic database, which will be made available online: a working tool for experts, useful to outline the cultural city stratification and to understand the Neapolitan archaeological sites through the material. It is useful in defining the topography of production (workshop, raw materials, and resources), distribution (communication routes, harbour, market), uses and consumption patterns (house, habitat, sacred areas, burials) in the city, even if lacking monumental evidence. It contributes to the reconstruction and analysis of the cultural and urban landscape, taking into account the geomorphological elements and the data contexts even in diachronic and transversal multi-disciplinary perspective. The analysis of some significant cases shows its validity also for potential alternative fruition. The integration of virtual reality systems is a possible extension also for the knowledge, enhancement, communication and use of cultural heritage

    Pre-sorting and pen size effects on the stress responses at loading and unloading and transport losses in market weight pigs

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    Transport losses represent three challenges for the US swine industry and these are: 1) pig well-being, 2) increased rules and regulations, and 3) direct financial losses to producers and packers. Therefore; improving the well-being of pigs during transport and reducing the incidence of dead and non-ambulatory pigs is a priority for the US swine industry (NPB, 2007). Johnson et al. (2010) studied the effects of grow-finish pen size and manually pre-sorting pigs the day before loading on the stress responses at loading and unloading and transport losses in market weight pigs. The authors reported that pigs loaded from large pens (192 pigs/pen) that were pre-sorted from pen mates had 66% fewer dead and non-ambulatory pigs at the harvest facility compared to pigs loaded from small pens (32 pigs/pen) that were sorted from pen mates during loading. However, it is unclear if the reduction in transport losses was due to pen size and/or pre-sorting before marketing. Therefore, the objectives of the current two research trials were to 1) determine the effects of pre-sorting prior to loading on stress responses and transport losses at the harvest facility in the market weight pig; and 2) determine the effects of grow-finish pen size on stress responses and transport losses at the harvest facility in the market weight pig
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