249 research outputs found

    A bienzymatic biocatalyst constituted by glucose oxidase and Horseradish peroxidase immobilized on ordered mesoporous silica

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    It is presently extremely challenging to realize an active immobilized multi-enzyme biocatalyst which allows to run in vitro multi-step cascade reactions. This work deals with the obtainment of a bienzymatic immobilized biocatalyst constituted by Glucose Oxidase (GOx) and Horseradish Peroxidase (HRP) immobilized onto SBA-15 mesoporous silica. The effect of co-immobilization (GOx/HRP@SBA-15) versus the separated immobilization (GOx@SBA-15/HRP@SBA-15), and the effect of covalent versus physical immobilization, on protein loading and enzymatic activity were investigated. Regardless the different immobilization strategy used, it was found that the catalytic activity could be retained only if the immobilized bienzymatic biocatalyst was kept wet. The obtained wet GOx/HRP@SBA-15 biocatalyst could be recycled 14 times keeping a good activity. Finally, the bienzymatic biocatalyst was tested for the oxidation of two model phenolic (caffeic acid and ferulic acid) pollutants of agricultural wastewaters, as olive mill wastewaters (OMWs). The biocatalyst was able to reach a 70% conversion within 15 min

    Working and Environmental Factors on Job Burnout: A Cross-sectional Study Among Nurses

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    Background: Burnout is a problem that impacts on the staff management costs and on the patient care quality. Objective: This work aimed to investigate some psychosocial factors related to burnout. Specifically, we explored the sample characteristics for moderate/high emotional exhaustion, cynicism and professional inefficacy, as well as the relationship between both working and environmental variables and burnout. Method: A cross-sectional study involving 307 nurses from one Italian hospital was carried out. A self-reported questionnaire was used to collect data. Data analysis was performed by using SPSS 19.0. Results: The results showed that there was a significant difference between nurses with low and moderate/high burnout in all the three components in almost all the examined organizational variables. In addition, we found that the aspects of working life had a significant impact on the three dimensions of burnout. Conclusions: The findings of this study not only can provide useful basis for future research in the field, but also can offer practical suggestions for improving nursing practice and promote effective workplace, thus reducing the risk burnout among nurse

    Anomalous suppression of the shot noise in a nanoelectromechanical system

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    In this paper we report a relaxation-induced suppression of the noise for a single level quantum dot coupled to an oscillator with incoherent dynamics in the sequential tunneling regime. It is shown that relaxation induces qualitative changes in the transport properties of the dot, depending on the strength of the electron-phonon coupling and on the applied voltage. In particular, critical thresholds in voltage and relaxation are found such that a suppression below 1/2 of the Fano factor is possible. Additionally, the current is either enhanced or suppressed by increasing relaxation, depending on bias being greater or smaller than the above threshold. These results exist for any strength of the electron-phonon coupling and are confirmed by a four states toy model.Comment: 7 pages, 7 eps figures, submitted to PRB; minor changes in the introductio

    Antioxidant activity of phenolic extracts from different cultivars of Italian onion (Allium cepa) and relative human immune cell proliferative induction

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    The total antioxidant activity (TAC) may vary considerably between onion cultivars. Immunological effects of onion phenolic compounds are still underestimated.The objective of this study is to determine the total phenol content (TPC) and the relative TAC of three Allium cepa L. (Liliaceae) onion cultivars cultivated in Cannara (Italy): Rossa di Toscana, Borettana di Rovato, and Dorata di Parma, and to evaluate the phenol extracts ability to induce human immune cell proliferation.TPC was determined by the Folin-Ciocalteu method, TAC with FRAP, TEAC/ABTS, and DPPH methods. Peripheral blood mononuclear cells from healthy human donors were incubated for 24 h at 37 °C with 1 ng/mL of phenolic extract in PBS, immunostained, and then analyzed by 4-color flow cytometry for the phenotypic characterization of T helper cells (CD4+ cells), cytotoxic T lymphocytes (CD8+ cells), T regulatory cells (CD25high CD4+ cells), and natural killer cells/monocytes (CD16+ cells).Rossa di Toscana displayed the highest TPC (6.61 ± 0.87 mg GA equivalents/g onion bulb DW) and the highest TAC with the experienced methods: FRAP, 9.19 ± 2.54 μmol Trolox equivalents/g onion bulb DW; TEAC/ABTS, 21.31 ± 0.41 μmol Trolox equivalents/g onion bulb DW; DPPH, 22.90 ± 0.01 μmol Trolox equivalents/g onion bulb DW. Incubation with Rossa di Toscana extract determined an increase in the frequency of the antitumor/anti-infection NK CD16+ immune cells (23.0 ± 0.4%).Content of health-promoting phenols and the deriving antioxidant and immunostimulating activity vary considerably among the investigated cultivars. Rossa di Toscana can be considered as a potential functional food

    A female survivor of childhood medulloblastoma presenting with growth-hormone-induced edema and inflammatory lesions: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>The improved survival of children with brain tumors has increased concerns about treatment-related sequelae. Growth hormone deficiency is frequently observed after craniospinal irradiation for medulloblastoma. It has been widely reported that growth hormone replacement therapy does not increase the risk of second tumors, but there are reports in the literature of growth hormone, and its downstream mediator insulin-like Growth Factor 1, having an important proinflammatory action. There are few reports, however, on the "in-vivo" induction of edema and symptomatic inflammatory lesions during replacement therapy.</p> <p>Case presentation</p> <p>We report the case of a 7-year-old girl treated for metastatic medulloblastoma who developed growth hormone deficiency 2 years after oncological treatment.</p> <p>Three months after replacement therapy, magnetic resonance imaging showed exacerbation of her brain edema, which was already present after oncological treatment. We consequently suspended the growth hormone until a new magnetic resonance image obtained 3 months later documented a reduction of the inflammatory areas. We then re-introduced somatotropin at lower doses with no further increase in brain edema in subsequent radiological controls.</p> <p>Conclusion</p> <p>This case and its iconography suggest a strong association between growth hormone administration and the exacerbation of inflammatory reactions within the tumor bed. Replacement therapy should be carefully monitored in this particular subset of patients.</p

    trabecular bone score tbs and bone metabolism in patients affected with type 1 neurofibromatosis nf1

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    In patients with neurofibromatosis type 1 (NF1), decreased bone mineral density (BMD) and low levels of 25-hydroxy vitamin D3 (25OHD) have been reported. Recently, the trabecular bone score (TBS) measurement has been proposed as index of bone microarchitecture and fracture risk. In 74 NF1 patients (48 females, 26 males, age 41 ± 12), we measured TBS and investigated clinical stage, lifestyle, vitamin D, serum bone turnover markers, vertebral and femoral BMD. A homogenous cohort of 61 healthy subjects was used as control group. TBS was lower in NF1 patients (1.266 ± 0.113 vs. 1.346 ± 0.105) without differences between sexes. No correlations with 25OHD, low exercise, low calcium intake, reduced sun exposure, and number of skin neurofibromas were observed. As expected, hypovitaminosis D was common (98.6%), as well as BMD reduction in hip and spine sites: In NF1 patients, bone texture evaluated by TBS was low in both sexes without any correlation with clinical or metabolic parameters, suggesting a direct role of the fibromin mutation

    Dimerization of GPCRs:Novel insight into the role of FLNA and SSAs regulating SST<sub>2</sub> and SST<sub>5</sub> homo- and hetero-dimer formation

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    The process of GPCR dimerization can have profound effects on GPCR activation, signaling, and intracellular trafficking. Somatostatin receptors (SSTs) are class A GPCRs abundantly expressed in pituitary tumors where they represent the main pharmacological targets of somatostatin analogs (SSAs), thanks to their antisecretory and antiproliferative actions. The cytoskeletal protein filamin A (FLNA) directly interacts with both somatostatin receptor type 2 (SST2) and 5 (SST5) and regulates their expression and signaling in pituitary tumoral cells. So far, the existence and physiological relevance of SSTs homo- and hetero-dimerization in the pituitary have not been explored. Moreover, whether octreotide or pasireotide may play modulatory effects and whether FLNA may participate to this level of receptor organization have remained elusive. Here, we used a proximity ligation assay (PLA)-based approach for the in situ visualization and quantification of SST2/SST5 dimerization in rat GH3 as well as in human melanoma cells either expressing (A7) or lacking (M2) FLNA. First, we observed the formation of endogenous SST5 homo-dimers in GH3, A7, and M2 cells. Using the PLA approach combined with epitope tagging, we detected homo-dimers of human SST2 in GH3, A7, and M2 cells transiently co-expressing HA- and SNAP-tagged SST2. SST2 and SST5 can also form endogenous hetero-dimers in these cells. Interestingly, FLNA absence reduced the basal number of hetero-dimers (-36.8 ± 6.3% reduction of PLA events in M2, P &lt; 0.05 vs. A7), and octreotide but not pasireotide promoted hetero-dimerization in both A7 and M2 (+20.0 ± 11.8% and +44.1 ± 16.3% increase of PLA events in A7 and M2, respectively, P &lt; 0.05 vs. basal). Finally, immunofluorescence data showed that SST2 and SST5 recruitment at the plasma membrane and internalization are similarly induced by octreotide and pasireotide in GH3 and A7 cells. On the contrary, in M2 cells, octreotide failed to internalize both receptors whereas pasireotide promoted robust receptor internalization at shorter times than in A7 cells. In conclusion, we demonstrated that in GH3 cells SST2 and SST5 can form both homo- and hetero-dimers and that FLNA plays a role in the formation of SST2/SST5 hetero-dimers. Moreover, we showed that FLNA regulatesSST2 and SST5 intracellular trafficking induced by octreotide and pasireotide. </p

    past present and future ultrasonographic techniques for analyzing ovarian masses

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    Ultrasonography is today the method of choice for distinguishing between benign and malignant adnexal pathologies. Using pattern recognition several types of tumors can be recognized according to their characteristic appearance on gray-scale imaging. Color Doppler imaging should be used only to perform a semiquantitative color score or evaluate the flow location. International Ovarian Tumor Analysis group had standardized definitions characterizing adnexal masses and suggested the use of 'simple rules' in premenopausal women. Recently, the use of 3D vascular indices has been proposed but its potential use in clinical practice is debated. Also computerized aided diagnosis algorithms showed encouraging results to be confirmed in the future

    The COVID-19 Student Stress Questionnaire: Validation in Spanish university students from health sciences

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    This study aimed to validate the Spanish version of the COVID-19 Student Stress Questionnaire (CSSQ), a 7-item tool assessing COVID-19-related stressors among university students, namely, Relationships and Academic Life, Isolation, and Fear of Contagion. Participants were 331 Spanish university students. Factor analyses sustained the three factor solution of the original tool. Data also revealed satisfactory convergent and discriminant validity, suitable internal consistency, and significant associations with psychological symptoms, as measured by the Symptom Checklist-90-Revised. The Spanish version of the CSSQ represents a valid tool to be used in clinical settings to timely identify students at high psychological risk and to develop evidence-based interventions during/after the pandemic

    VALIDATED PUNGENCY ASSESSMENT OF THREE ITALIAN ONION (ALLIUM CEPA L.) CULTIVARS

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    Abstract In the frame of a broad multidisciplinary study aimed at enlightening the peculiarities of three onion cultivars (Dorata di Parma, Borettana and Rossa di Toscana
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