Protective role of natural and semi-synthetic tocopherols on TNFα-induced ros production and ICAM-1 and Cl-2 expression in ht29 intestinal epithelial cells

Vitamin E, a fat-soluble compound, possesses both antioxidant and non-antioxidant properties. In this study we evaluated, in intestinal HT29 cells, the role of natural tocopherols, α-Toc and δ-Toc, and two semi-synthetic derivatives, namely bis-δ-Toc sulfide (δ-Toc)2S and bis-δ-Toc disulfide (δ-Toc)2S2, on TNFα-induced oxidative stress, and intercellular adhesion molecule-1 (ICAM-1) and claudin-2 (Cl-2) expression. The role of tocopherols was compared to that of N-acetylcysteine (NAC), an antioxidant precursor of glutathione synthesis. The results show that all tocopherol containing derivatives used, prevented TNFα-induced oxidative stress and the increase of ICAM-1 and Cl-2 expression, and that (δ-Toc)2S and (δ-Toc)2S2 are more effective than δ-Toc and α-Toc. The beneficial effects demonstrated were due to tocopherol antioxidant properties, but suppression of TNFα-induced Cl-2 expression seems not only to be related with antioxidant ability. Indeed, while ICAM-1 expression is strongly related to the intracellular redox state, Cl-2 expression is TNFα-up-regulated by both redox and non-redox dependent mechanisms. Since ICAM-1 and Cl-2 increase intestinal bowel diseases, and cause excessive recruitment of immune cells and alteration of the intestinal barrier, natural and, above all, semi-synthetic tocopherols may have a potential role as a therapeutic support against intestinal chronic inflammation, in which TNFα represents an important proinflammatory mediator

Simulation and comparison of coils for Hyperpolarized 13C MRS cardiac metabolism studies in pigs

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Rapid detection of intestinal carriage of Klebsiella pneumoniae producing KPC carbapenemase during an outbreak

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pH Switchable Water Dispersed Photocatalytic Nanoparticles

Photogeneration of Reactive Oxygen Species (ROS) finds applications in fields as different as nanomedicine, art preservation, air and water depollution and surface decontamination. Here we present photocatalytic nanoparticles (NP) that are active only at acidic pH while they do not show relevant ROS photo-generation at neutral pH. This dual responsivity (to light and pH) is achieved by stabilizing the surface of TiO2 NP with a specific organic shell during the synthesis and it is peculiar of the achieved core shell-structure, as demonstrated by comparison with commercial photocatalytic TiO2 NP. For the investigation of the photocatalytic activity, we developed two methods that allow real time detection of the process preventing any kind of artifact arising from post-treatments and delayed analysis. The reversibility of the pH response was also demonstrated as well as the selective photo-killing of cancer cells at acidic pH

Comparison of screening tools for the detection of neurocognitive impairment in HAART-treated patients

Background: Neurocognitive impairment (NCI) and HIV-associated neurocognitive disorders (HAND) remain prevalent despite HAART. We examined sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and correct classification rate (CCR) of screening tools for the detection of NCI and HAND in HAART treated patients. Methods: We examined 101 unselected HAART-treated patients. Patients were administered the self-reported three questions (EACS Guidelines), the International HIV-Dementia Scale (IHDS), the Mini-Mental Status Examination (MMSE), and a comprehensive 6-domain (17-test) neuropsychological (NP) battery (120 minutes) that included, among others, the Digit Symbol (DS), the Trail Making Modalities (TM), and the Grooved Pegboard (GP) tests. NCI was defined according to the AAN criteria. HAND was diagnosed after exclusion of confounding conditions. Results: Our cohort was relatively healthy (mean CD4 count: 575 cells/mm3, undetectable plasma HIV RNA 85%). Prevalence of NCI and HAND were 39.6% (40 of 101) and 30.7% (31 of 101), respectively. Mean scores of IHDS (9.9 vs 10.8; p<0.001) and MMSE (26.8 vs 28.2; p=0.004) differed significantly between impaired and unimpaired patients, while mean three-questions scores (8.0 vs 7.0; p=0.23) did not. The three questions showed also poor sensitivity for the detection of both NCI (20%) and HAND (22%). The IHDS showed fairly good sensitivity (55%) and NPV (73.5%). Adding to the IHDS some easy to administer NP tests, i.e. TM, DS, and GP, resulted in an increase in sensitivity and NPV for the detection of NCI (table). Similar results were obtained regarding the detection of HAND (not shown in table). Conclusions: Both NCI and HAND are still very prevalent in HAART-treated patients. Among screening tools the self-reported three question show poor sensitivity. The IHDS performed better in terms of sensitivity, PPV, and NPV. Combinations of easy-to-administer NP tests with the IHDS resulted in increased sensitivity and NPV. Combining IHDS with one or two simple NP test may represent an improvement in the screening approach to the detection of both NCI and HAND

The analog signal processor of the Auger fluorescence detector prototype

The Auger Fluorescence Detector will allow to determine the longitudinal development of atmospheric showers in the range 10 19 –10 21 eV. A detector module comprises an array of 20 � 22 PMTs at the focal surface of a large-aperture telescope. Thirty such modules will be used. The PMTs pixel signal is variable in shape depending on the shower-eye geometry. The sky background light (BL) is also variable. We have developed an analog signal processor to obtain best energy and timing resolution despite those constrains. The Head Electronics (HE) bias the PMTs and keeps its pulsegain constant even for large BL. This is measured using a current-monitor of novel design. Both the signal pulse and the BL DC level are sent via a single twisted pair to the Analog Board (AB). The AB performs the compression of the 15–16 bit signal dynamic range into 12 bits of the FADC which follows the AB. A three-pole Bessel filter was adopted for antialiasing. The AB includes 16 bit sigma-delta chips to readout the BL DC level, and a test-pulse distribution system. # 2001 Elsevier Science B.V. All rights reserved. PACS: 29.4

Bloodstream infections in patients with rectal colonization by Klebsiella pneumoniae producing different type of carbapenemases: a prospective, cohort study

Objective: To investigate the hypothesis that intestinal colonization by different types of carbapenemase-resistant Klebsiella pneumoniae (CR-Kp) leads to different risks for bloodstream infections (BSI) caused by the same colonizing organism. Methods: Prospective observational study including consecutive CR-Kp rectal carriers admitted to the Pisa University Hospital (December 2018 to December 2019). Patients underwent rectal swabbing with molecular testing for the different carbapenemases at hospital admission and during hospitalization. Rectal carriers were classified as: NDM, KPC, VIM and OXA-48. The primary end point was the rate of BSI by the same colonizing organism in each study group. A multivariate logistic regression analysis was performed to identify factors independently associated with the risk for BSI by the colonizing organism. Results: Of 677 rectal carriers, 382/677 (56.4%) were colonized by NDM, 247/677 (36.5%) by KPC, 39/677 (5.8%) by VIM and 9/677 (1.3%) by OXA-48. Dissemination of NDM-Kp was mostly sustained by ST147, while KPC-Kp belonged to ST512. A higher rate of BSI was documented in NDM rectal carriers compared with KPC rectal carriers (59/382, 15.4% versus 20/247, 8.1%, p 0.004). Incidence rates of BSI per 100 patients/month were significantly higher in the NDM group (22.33, 95% CI 17.26-28.88) than in the KPC group (9.56, 95% CI 6.17-14.82). On multivariate analysis, multi-site extraintestinal colonization, solid organ transplantation, invasive procedures, intravascular device, admission to intensive care unit, cephalosporin, fluoroquinolones and NDM rectal colonization (OR 3.27, 95% CI 1.73-6.18, p < 0.001) were independently associated with BSI. Conclusions: NDM-Kp was associated with increased risk of BSI compared with KPC-Kp. This finding seems to be strongly related to the high-risk clone ST147

A magnetization transfer study of mild and advanced Parkinson's disease

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