674 research outputs found

    Platelet lysate maintains chondrogenic potential and promotes cartilage regeneration

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    cartilage. We report the biological effect of the platelet lysate (PL), a PRP derivative, on primary human articular chondrocytes (HAC) cultured under both physiological and inflammatory condition. Added to the culture medium, PL induced a strong mitogenic response in the chondrocytes. The in vitro expanded cell population maintained a chondrogenic re-­‐differentiation potential as revealed by micromass culture in vitro as well as in vivo as demonstrated by ectopic cartilage formation in nude mice. Furthermore, in chondrocytes cultured in the presence of the pro-­‐inflammatory cytokine IL-­‐1α, the PL induced a drastic enhancement of the synthesis of the cytokines IL-­‐6 and IL-­‐8 and of NGAL, a lipocalin expressed in cells of the chondrogenic lineage. These events were controlled by the p38 MAP kinase and NF-­‐κΒ pathways. The pro-­‐inflammatory effect of the PL was a transient phenomenon. In fact, after an initial up regulation, we observed a significant reduction of the NF-­‐κΒ activity together with the repression of the inflammatory enzyme ciclooxygenase-­‐2 (COX-­‐2). Moreover, the medium of chondrocytes cultured in the contemporary presence of PL and IL-­‐1α, showed a significant enhancement of the chemoattractant activity versus untreated chondrocytes. On the whole, our findings support the concept that the platelet products have a direct beneficial effect on articular chondrocytes and at the same time could drive in sequence a trans

    Radioisotopic purity and imaging properties of cyclotron-produced 99mTc using direct 100Mo(p,2n) reaction

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    Evaluation of the radioisotopic purity of technetium-99m (99mTc) produced in GBq amounts by proton bombardment of enriched molibdenum-100 (100Mo) metallic targets at low proton energies (i.e. within 15\u201320 MeV) is conducted. This energy range was chosen since it is easily achievable by many conventional medical cyclotrons already available in the nuclear medicine departments of hospitals. The main motivation for such a study is in the framework of the research activities at the international level that have been conducted over the last few years to develop alternative production routes for the most widespread radioisotope used in medical imaging. The analysis of technetium isotopes and isomeric states (9xTc) present in the pertechnetate saline Na99mTcO4 solutions, obtained after the extraction/purification procedure, reveals radionuclidic purity levels basically in compliance with the limits recently issued by European Pharmacopoeia 9.3 (2018 Sodium pertechnetate (99mTc) injection 4801\u20133). Moreover, the impact of 9xTc contaminant nuclides on the final image quality is thoroughly evaluated, analyzing the emitted high-energy gamma rays and their influence on the image quality. The spatial resolution of images from cyclotron-produced 99mTc acquired with a mini-gamma camera was determined and compared with that obtained using technetium-99m solutions eluted from standard 99Mo/99mTc generators. The effect of the increased image background contribution due to Compton-scattered higher-energy gamma rays (E \u3b3 \u2009\u2009>\u2009\u2009200\u2009keV), which could cause image-contrast deterioration, was also studied. It is concluded that, due to the high radionuclidic purity of cyclotron-produced 99mTc using 100Mo(p,2n)99mTc reaction at a proton beam energy in the range 15.7\u201319.4 MeV, the resulting image properties are well comparable with those from the generator-eluted 99mTc

    Utilização de chuveiros na sala pré-ordenha e sua influência na produtividade de búfalas da raça Murrah (Bubalus bubalis).

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    O estudo foi realizado com 64 búfalas, em dois tratamentos (1 e 2), durante seis dias. No primeiro, antes da ordenha, os animais permaneceram 1h em sala de espera com acesso ao chuveiro No segundo, os animais não tiveram acesso ao chuveiro. Foram registrados Índice de Temperatura de Globo e Umidade (ITGU) e a Umidade Relativa (UR) das salas de ordenha e de espera, Temperatura de Corpo (TC), Frequência Respiratória (FR), Reatividade (REAT), Nível de Estresse (NEST) e a Produção Diária de Leite (PL). Os dados foram analisados com o auxílio do programa SAS. O efeito da FR não foi significativo (P>0,57) sobre a PL. Não houve diferença significativa na PL para a REAT. O NEST foi o mesmo nos dois tratamentos. As regressões da característica (PL_AJ) sobre ITGU Interno (ITGU_I), ITGU Externo (ITGU_E), TC e UR não foram significativas (P>0,12). No tratamento 2 foram observados maior número de animais em classes de estresse, verificou-se que o tratamento 1 possibilitou a mudança ( alguns animais) da zona de alerta ou estresse para a zona de conforto térmico em relação ao ITGU_I. No tratamento 2, todos os animais estavam em estresse térmico. Os animais submetidos ao estresse calórico em ambas as situações utilizaram com eficiência o seu sistema termorregulador, sem interferir na produção de leite

    Detectors for the James Webb Space Telescope Near-Infrared Spectrograph I: Readout Mode, Noise Model, and Calibration Considerations

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    We describe how the James Webb Space Telescope (JWST) Near-Infrared Spectrograph's (NIRSpec's) detectors will be read out, and present a model of how noise scales with the number of multiple non-destructive reads sampling-up-the-ramp. We believe that this noise model, which is validated using real and simulated test data, is applicable to most astronomical near-infrared instruments. We describe some non-ideal behaviors that have been observed in engineering grade NIRSpec detectors, and demonstrate that they are unlikely to affect NIRSpec sensitivity, operations, or calibration. These include a HAWAII-2RG reset anomaly and random telegraph noise (RTN). Using real test data, we show that the reset anomaly is: (1) very nearly noiseless and (2) can be easily calibrated out. Likewise, we show that large-amplitude RTN affects only a small and fixed population of pixels. It can therefore be tracked using standard pixel operability maps.Comment: 55 pages, 10 figure

    Basic Course Leadership: Operational Transparency as a Best Practice for Adjunct Faculty Management

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    Research suggests adjunct faculty receive little institutional support and feel a sense of disconnection from their campuses. Nearly half of all faculty at American colleges and universities are classified as adjunct faculty in recent National Center for Educational Statistics reporting. Thus, academic departments should consider strategies to better include and engage adjunct faculty on their campuses. This article explores transparency as a best practice for the administration of communication basic courses at a mid-sized, regional university. Further, adjunct faculty members’ perceptions of the basic course administrators’ transparency will be discussed
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