Role of Oxidative Stress Mediated by Glutathione-S-transferase in Thiopurines' Toxic Effects

Azathioprine (AZA), 6-mercaptopurine (6-MP), and 6-thioguanine (6-TG) are antimetabolite drugs, widely used as immunosuppressants and anticancer agents. Despite their proven efficacy, a high incidence of toxic effects in patients during standard-dose therapy is recorded. The aim of this study is to explain, from a mechanistic point of view, the clinical evidence showing a significant role of glutathione-S-transferase (GST)-M1 genotype on AZA toxicity in inflammatory bowel disease patients. To this aim, the human nontumor IHH and HCEC cell lines were chosen as predictive models of the hepatic and intestinal tissues, respectively. AZA, but not 6-MP and 6-TG, induced a concentration-dependent superoxide anion production that seemed dependent on GSH depletion. N-Acetylcysteine reduced the AZA antiproliferative effect in both cell lines, and GST-M1 overexpression increased both superoxide anion production and cytotoxicity, especially in transfected HCEC cells. In this study, an in vitro model to study thiopurines' metabolism has been set up and helped us to demonstrate, for the first time, a clear role of GST-M1 in modulating AZA cytotoxicity, with a close dependency on superoxide anion production. These results provide the molecular basis to shed light on the clinical evidence suggesting a role of GST-M1 genotype in influencing the toxic effects of AZA treatment

PACSIN2 as a modulator of autophagy and mercaptopurine cytotoxicity: mechanisms in lymphoid and intestinal cells

PACSIN2 variants are associated with gastrointestinal effects of thiopurines and thiopurine methyltransferase activity through an uncharacterized mechanism that is postulated to involve auto-phagy. This study aims to clarify the role of PACSIN2 in autophagy and in thiopurine cytotoxicity in leukemic and intestinal models. Higher autophagy and lower PACSIN2 levels were observed in inflamed compared with non-inflamed colon biopsies of in-flammatory bowel disease pediatric patients at diagnosis. PAC-SIN2 was identified as an inhibitor of autophagy, putatively through inhibition of autophagosome formation by a protein- protein interaction with LC3-II, mediated by a LIR motif. Moreover, PACSIN2 resulted a modulator of mercaptopurine-induced cyto-toxicity in intestinal cells, suggesting that PACSIN2-regulated autophagy levels might influence thiopurine sensitivity. However, PACSIN2 modulates cellular thiopurine methyltransferase activity via mechanisms distinct from its modulation of autophagy

Outdoor education: are we really ready?

Outdoor education (OE) has recently gained popularity also in Italy, especially after the indoor confinement experienced due to the pandemic. OE has shown to foster children’s stress recovery, cognitive performance, and affiliation with Nature, exploiting benefits produced by natural ecosystems (i.e. the Ecosystem Services, ES). To explore the hypothesis to implement OE programs in the Venice lagoon, we assessed the “information for cognitive development” ES focusing on the valli da pesca, a peculiar habitat of the lagoon that still maintain the main features of transitional waters environments. According to the results of our questionnaire addressed to teachers in the Metropolitan City of Venice, all the respondents would be very interested in conducting OE in such environments, suggesting a high demand that could potentially involve more than 2700 teachers. Obtained results, however, revealed that 37.5% of the teachers are frightened by the additional bureaucratic effort it might require, and 20.8% expressed concerns about risk/safety conditions. The results reveal also that their current idea of OE is more similar to schoolyard playtime, or to the occasional engagement in a school trip: 40.2% of the interviewed teachers consider indeed one trip per year sufficient to stand for OE, whereas only 3.9% agreed that the ideal frequency should be at least one day per month. Another frequently reported drawback dwells with the difficulty of adapting for OE a frontal lesson on the topics addressed in the classroom. Therefore, despite the high capacity of the valli da pesca to provide suitable places for OE, we highlight that a non-negligible portion of the local school system does not seem currently ready for this kind of experience, as they are portrayed simply like “experiences outside the classroom” where the environmental features don't really ‘make the difference’. The concerns expressed by the majority of the interviewed teachers suggest they need strong support in implementing a real OE program, as opposed to just “teaching in outdoor settings”, so that lack of the classical teaching tools (such as blackboard, desks and school furniture) is not seen anymore as an obstacle, but as an opportunity to discover the affordances of the environmental elements that could stimulate the students to learn-by-doing

Pharmacogenetics of thiopurines

Polychemotherapeutic protocols for the treatment of pediatric acute lymphoblastic leukemia (ALL) always include thiopurines. Specific approaches vary in terms of drugs, dosages and combinations. Such therapeutic schemes, including risk-adapted intensity, have been extremely successful for children with ALL who have reached an outstanding 5-year survival of greater than 90% in developed countries. Innovative drugs such as the proteasome inhibitor bortezomib and the bi-specific T cell engager blinatumomab are available to further improve therapeutic outcomes. Nevertheless, daily oral thiopurines remain the backbone maintenance or continuation therapy. Pharmacogenetics allows the personalization of thiopurine therapy in pediatric ALL and clinical guidelines to tailor therapy on the basis of genetic variants in TPMT and NUDT15 genes are already available. Other genes of interest, such as ITPA and PACSIN2, have been implicated in interindividual variability in thiopurines efficacy and adverse effects and need additional research to be implemented in clinical protocols. In this review we will discuss current literature and clinical guidelines available to implement pharmacogenetics for tailoring therapy with thiopurines in pediatric ALL

5% Lidocaine Hydrochloride Cream for Wound Pain Relief: A Multicentre Observational Study

Background: Lidocaine hydrochloride is frequently used for management of painful wounds. This prospective, multicentre study examined the effects of 5% lidocaine cream on wound pain relief. Material and methods: The study included 78 patients with painful wounds treated with 5% Lidocaine cream for two weeks in two Italian Hospitals. Patients' perception of pain was recorded by, using the 5-point Visual Rate Scale and the 11-point Numerical Pain Rating Scale. All medications and adverse events were evaluated in a daily diary. The primary outcome of the study was establishing the wound pain relief based on the results of 5-VRS and pain intensity based on the 11-NPRS testing from baseline to the end of treatment. Clinical aspects and adverse events were also collected. Results: Seventy-eight patients had a median age of 67.5 years (range 18-96 years). 62.8% were women. The wounds included traumatic wounds (n = 39), venous ulcers (n = 25), post-surgical wounds (n = 6) pyoderma gangrenosum (n = 6), vasculitis (n = 1) and pressure ulcer (n = 1). The intensity of pain significantly decreased from the baseline level established at the beginning of treatment (mean score 6.7 - 1.90) - to the level at end of treatment (3.0 - 2.23-; p < 0.0001). 9 patients prematurely stopped the treatment for healing (n = 4), wound improvement (n = 2) and adverse events related to the treatment. (n = 3). 13 patients presented a total of 25 adverse events, 4 of them were related to the treatment. Conclusion: The treatment of painful wounds with 5% Lidocaine Cream for 14 days resulted in reduced pain intensity, and showed high safety and tolerability

5% Lidocaine Hydrochloride Cream for Wound Pain Relief: A Multicentre Observational Study

Background Lidocaine hydrochloride is frequently used for management of painful wounds. This prospective, multicentre study examined the effects of 5% lidocaine cream on wound pain relief. Material and methods The study included 78 patients with painful wounds treated with 5% Lidocaine cream for two weeks in two Italian Hospitals. Patients’ perception of pain was recorded by, using the 5-point Visual Rate Scale and the 11-point Numerical Pain Rating Scale. All medications and adverse events were evaluated in a daily diary. The primary outcome of the study was establishing the wound pain relief based on the results of 5-VRS and pain intensity based on the 11-NPRS testing from baseline to the end of treatment. Clinical aspects and adverse events were also collected. Results Seventy-eight patients had a median age of 67.5 years (range 18-96 years). 62.8% were women. The wounds included traumatic wounds (n = 39), venous ulcers (n = 25), post-surgical wounds (n = 6) pyoderma gangrenosum (n = 6), vasculitis (n = 1) and pressure ulcer (n = 1). The intensity of pain significantly decreased from the baseline level established at the beginning of treatment (mean score 6.7 − 1.90) - to the level at end of treatment (3.0 − 2.23-; p < 0.0001). 9 patients prematurely stopped the treatment for healing (n = 4), wound improvement (n = 2) and adverse events related to the treatment. (n = 3). 13 patients presented a total of 25 adverse events, 4 of them were related to the treatment. Conclusion The treatment of painful wounds with 5% Lidocaine Cream for 14 days resulted in reduced pain intensity, and showed high safety and tolerability

Electrical and Electroluminescence Characteristics of AlGaN/GaN High Electron Mobility Transistors Operated in Sustainable Breakdown Conditions

This paper reports on an extensive analysis of the electrical and optical properties of GaN-based high electron mobility transistors (HEMTs) biased in a non-destructive breakdown regime. By means of a number of measurements carried out with varying voltage and temperature conditions, we show that: (i) HEMTs can reach a sustainable breakdown condition, when they are biased in current-controlled mode, with a gate voltage smaller than the pinch-off voltage; (ii) when biased in sustainable breakdown, HEMTs can emit a weak luminescence signal, localized in proximity of the drain edge; (iii) the breakdown voltage (BDV) is strongly dependent on temperature. Through a careful investigation of the drain, source and gate current components, we demonstrate that breakdown originates from two different mechanisms, depending on the gate voltage: for gate voltages close to the pinch-off, breakdown current originates from the space charge injection of electrons from the source to the drain. On the other hand, for more negative gate voltages, breakdown current originates from the injection of electrons from the gate. Finally, the analysis of the temperature dependence of the breakdown current confirms that two different mechanisms significantly contribute to current conduction at high drain voltage level

Influence of Fluorine-Based Dry Etching on Electrical Parameters of AlGaN/GaN-on-Si High Electron Mobility Transistors

The fluorine-based dry etching process is extensively employed in the fabrication of GaN-based High Electron Mobility Transistors. This research activity aims to the identification of the SF6 ICP etching process effects on the performances of depletion-mode AlGaN/GaN-on-Si HEMTs. By means of reverse-bias step-stress and time-resolved constant-stress, it has been observed (i) a short-term instability of both threshold voltage and gate leakage current under low reverse bias conditions, likely related to the permanent modification of electrical configuration of the Fluorine ions implanted within the epitaxial structure during the etching process; and (ii) that the introduction of the annealing phase mitigates the described instability

Biological versus mechanical aortic valve replacement in non-elderly patients: a single-centre analysis of clinical outcomes and quality of life

The aim of this study was to evaluate short- and long-term clinical outcomes, including the perceived health-related quality of life, in patients younger than 65\u2009years having undergone aortic valve replacement either with biological or mechanical valve prostheses

Long-term performance of colorectal cancer screening programmes based on the faecal immunochemical test

BACKGROUND: The long-term performance of colorectal cancer (CRC) screening programmes based on a 2-year faecal immunochemical test (FIT) is still unclear. METHODS: In a sample of 50 to 69-year-olds repeatedly screened with the FIT (OC-Hemodia latex agglutination test; cut-off: 20\u2009\ub5g haemoglobin/g faeces), we examined: (1) the FIT positivity rate, the CRC and advanced adenoma detection rate and the FIT's positive predictive value (PPV) for advanced neoplasia, at each round of screening and (2) the cumulative CRC and advanced adenoma detection rate after five rounds of FIT. RESULTS: Over 12 years (2002-2014), 123\u2009347 individuals were administered the FIT up to six times, and 781 CRCs and 4713 advanced adenomas were diagnosed. The CRC and advanced adenoma detection rates declined substantially from the first to the third (rate ratio (RR) 0.25, 95%\u2009CI 0.20 to 0.32) and second (RR 0.51, 95%\u2009CI 0.47 to 0.56) rounds, respectively, and then remained stable. The PPV for advanced neoplasia dropped by 18% in the second round (RR 0.82, 95%\u2009CI 0.77 to 0.89), with no further reduction thereafter due to a concomitant decline in the FIT positivity rate (RR first to sixth rounds: 0.56, 95%\u2009CI 0.53 to 0.60).The cumulative CRC and advanced adenoma detection rates over five consecutive rounds were 8.5\u2030 (95%\u2009CI 7.8 to 9.2), and 58.9\u2030 (95%\u2009CI 56.9 to 61.0), rectively. CONCLUSIONS: Repeated FIT significantly reduces the burden of colorectal disease while facilitating an efficient use of colonoscopy resources. The cumulative detection rate after five rounds of FIT is similar to primary screening with colonoscopy, supporting the need to account for the cumulative sensitivity of repeated FITs when evaluating the test's efficacy