601 research outputs found

    JCV-specific T-cells producing IFN-gamma are differently associated with PmL occurrence in HIV patients and liver transplant recipients

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    Aim of this work was to investigate a possible correlation between the frequency of JCV-specific T-cells and PML occurrence in HIV-infected subjects and in liver transplant recipients. A significant decrease of JCV-specific T-cells was observed in HIV-PML subjects, highlighting a close relation between JCV-specific T-cell immune impairment and PML occurrence in HIV-subjects. Interestingly, liver-transplant recipients (LTR) showed a low frequency of JCV-specific T-cells, similar to HIV-PML subjects. Nevertheless, none of the enrolled LTR developed PML, suggesting the existence of different immunological mechanisms involved in the maintenance of a protective immune response in LT

    Design and simulation of a solar assisted desiccant-based air handling unit

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    Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.Desiccant-based Air Handling Units (AHU) can guarantee significant technical and energy/environmental advantages related to the use of traditional ones (with dehumidification by cooling). For these reasons, a test facility has been located in Benevento (Southern Italy), in which a silica-gel desiccant wheel is inserted in an AHU which treats outside air only. For this wheel, the regeneration temperature can be as low as 65 °C, therefore energy savings and emissions reductions are more consistent when the regeneration of the desiccant material is obtained by means of available low grade thermal energy, such as that from solar collectors or cogenerators. In the actual configuration, regeneration is obtained by means of thermal energy recovered from a micro-cogenerator (MCHP, Micro Combined Heat and Power) based on a natural gas-fired reciprocating internal combustion engine, eventually integrated through a natural gas-fired boiler. Future activity aims to reduce the regeneration fossil energy requirements by introducing a solar collector system that substitutes or integrates thermal energy supplied by the MHCP. To this aim, a commercial software has been used to design the solar collector system (collectors type, absorber area, water flow rate…) considering the thermal power and temperature requirements of the regeneration process. The existing AHU and the designed solar collector system have been successively simulated by means of TRNSYS software, in order to evaluate operational data and performance parameters of the system in a typical week of operation, e.g. thermal-hygrometric conditions of air in the mean sections of the AHU, solar collectors efficiency and solar fraction.mp201

    Energy and exergy-based indicators

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    SUMMARY The current increase of the energy consumption of buildings requires new approaches to solve economic, environmental and regulatory issues. Exergy methods are thermodynamic tools searching for sources of inefficiencies in energy conversion systems that the current energy techniques may not identify. Desiccant cooling systems (DCS) are equipments applied to dehumidifying and cooling air streams, which may provide reductions of primary energy demand relatively to conventional air-conditioning units. In this study, a detailed thermodynamic analysis of open-cycle DCS is presented. It aims to assess the overall energy and exergy performance of the plant and identify its most inefficient sub-components, associated to higher sources of irreversibilities. The main limitations of the energy methods are highlighted, and the opportunities given by exergy approach for improving the system performance are properly identified. As case study, using a pre-calibrated TRNSYS model, the overall energy and exergy efficiency of the plant were found as 32.2% and 11.8%, respectively, for a summer week in Mediterranean climate. The exergy efficiency defect identified the boiler (69.0%) and the chiller (12.3%) as the most inefficient components of the plant, so their replacement by high efficient systems is the most rational approach for improving its performance. As alternative heating system to the boiler, a set of different technologies and integration of renewables were proposed and evaluated applying the indicators: primary energy ratio (PER) and exergy efficiency. The heating system fuelled by wood was found as having the best primary energy performance (PER = 109.6%), although the related exergy efficiency is only 11.4%. The highest exergy performance option corresponds to heat pump technology with coefficient of performance (COP) = 4, having a PER of 50.6% and exergy efficiency of 28.2%. Additionally, the parametric analyses conducted for different operating conditions indicate that the overall irreversibility rate increases moderately for larger cooling effects and more significant for higher dehumidification rates. Copyright © 2013 John Wiley & Sons, Ltd

    Fine-needle cytology in the follow-up of breast carcinoma

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    The postoperative follow-up strategies for breast carcinoma (BC) utilize different procedures; the aim of this study was to investigate the role of fine-needle cytology (FNC) in the follow-up of BC patients. Two hundred sixty-six FNC samples from 190 BC patients have been reviewed. The target anatomical sites were 190 breast including 155 ipsilateral and 145 contralateral breast lesions and 76 extra-mammary nodules. Extra-mammary lesions included lymph nodes, thyroidal nodules, soft tissue lesions, (subcutaneous and sub-scars), salivary glands and deep located masses. Diagnostic distribution of the breast lesions was as follows: 51 positive, 15 indeterminate/suspicious, 119 negative and 5 inadequate. Positive cases included 43 ipsilateral and 8 contralateral BC, 9 BC in different quadrants from those of onset of the first BC. Sensitivity, specificity and accuracy have been 90, 91 and 90&, respectively. FNC, in a correct setting, is a reliable and effective method for the follow-up management of BC patients

    Search for carbonaceous chondrites evidence on Vesta through the detection of carbonates

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    NASA’s Dawn mission was launched in September 2007 and orbited asteroids Vesta (2011 2012) and Ceres (2015–2018). Vesta shows surface dark units that have been suggested to be linked to exogenous materials and are therefore useful to understand the initial stages of the Solar System. This work takes advantage of the newly calibrated data of the VIR spectrometer, which are characterized by a better signal to noise (S/N) ratio, giving us the opportunity to search for spectral features that were never seen before due to noise. Considering that hydroxyl has been shown to be present in every dark unit on Vesta and also in carbonaceous chondrites, the goals of this work are the search for and characterization of carbonates that are present in carbonaceous chondrites, i.e., the supposed darkening agents of Vesta. The estimate of the abundances of carbonates is fundamental to identify which carbonaceous chondrite fell on Vesta; this can be crucial for the definition of an evolutionary history of Vesta and the Solar System. The study of a possible feature at 3.9 μm related to the presence of carbonates was analyzed and found to be noise-induced. Although spectral features related to carbonates were not observed, the 3.4 μm absorption band was analyzed anyway in order to fix an upper limit to the abundance of carbonates in carbonaceous chondrites on Vesta. This value is consistent with petrochemical analyses, i.e., no more than 0.2% of carbonates in carbonaceous chondrites

    New frontiers in bariatric surgery laparoscopic adjustable silicone gastric banding (LASGB)

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    LASGB is a minimally invasive procedure indicated for the treatment of morbid obesity. Since January 1996, six patients have successfully undergone the laparoscopic procedure. Preoperative BMI was 42 ± 3.1; range 39-46. Mean operative time was 260 ± 110, range was 160-360. Mean hospital stay was 3 ± 1 days

    Specific Protein 1 and p53 Interplay Modulates the Expression of the KCTD-Containing Cullin3 Adaptor Suppressor of Hedgehog 2

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    The Hedgehog (Hh) signaling pathway plays a crucial role in normal embryonic development and adult tissue homeostasis. On the other end, dysregulated Hh signaling triggers a prolonged mitogenic response that may prompt abnormal cell proliferation, favoring tumorigenesis. Indeed, about 30% of medulloblastomas (MBs), the most common malignant childhood cerebellar tumors, exhibit improper activation of the Hh signaling. The oncosuppressor KCASH2 has been described as a suppressor of the Hh signaling pathway, and low KCASH2 expression was observed in Hh-dependent MB tumor. Therefore, the study of the modulation of KCASH2 expression may provide fundamental information for the development of new therapeutic approaches, aimed to restore physiological KCASH2 levels and Hh inhibition. To this end, we have analyzed the TATA-less KCASH2 proximal promoter and identified key transcriptional regulators of this gene: Sp1, a TF frequently overexpressed in tumors, and the tumor suppressor p53. Here, we show that in WT cells, Sp1 binds KCASH2 promoter on several putative binding sites, leading to increase in KCASH2 expression. On the other hand, p53 is involved in negative regulation of KCASH2. In this context, the balance between p53 and Sp1 expression, and the interplay between these two proteins determine whether Sp1 acts as an activator or a repressor of KCASH2 transcription. Indeed, in p53–/– MEF and p53 mutated tumor cells, we hypothesize that Sp1 drives promoter methylation through increased expression of the DNA methyltransferase 1 (DNMT1) and reduces KCASH2 transcription, which can be reversed by Sp1 inhibition or use of demethylating agents. We suggest therefore that downregulation of KCASH2 expression in tumors could be mediated by gain of Sp1 activity and epigenetic silencing events in cells where p53 functionality is lost. This work may open new venues for novel therapeutic multidrug approaches in the treatment of Hh-dependent tumors carrying p53 deficiency
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