Oxidative status in different settings and with different methodological approaches compared by Receiver Operating Characteristic curve analysis

Objectives: To test the performance of different analytical approaches in highlighting the occurrence of deregulated redox status in various physio-pathological situations. Design and methods: 35 light and 61 heavy smokers, 19 chronic renal failure, 59 kidney transplanted patients, and 87 healthy controls were retrospectively considered for the study. Serum oxidative stress and antioxidant status, assessed by spectrophotometric Reactive Oxygen Metabolites (d-ROMs) and Total Antioxidant Capacity (TAC) tests, respectively, were compared with plasma free (F-MDA) and total (T-MDA)malondialdehyde, both quantified by isotope-dilution-gas chromatography\u2013mass spectrometry (ID-GC\u2013MS). Sensitivity, specificity and cut-off points of T-MDA, F-MDA, d-ROMs and TAC were evaluated by both Receiver Operating Characteristic (ROC) analyses and area under the ROC curve (AUC). Results: Only T-MDA assay showed a clear absence of oxidative stress in controls and significant increase in all patients (AUC 1.00, sensitivity and specificity 100%). Accuracy was good for d-ROMs (AUC 0.87, sensitivity 72.8%, specificity 100%) and F-MDA (AUC 0.82, sensitivity 74.7%, specificity 83.9%), but not high enough for TAC to show in patients impaired antioxidant defense (AUC 0.66, sensitivity 52.0%, specificity 92.9%). Conclusions: This study reveals T-MDA as the best marker to detect oxidative stress, shows the ability of d-ROMs to identify modified oxidative status particularly in the presence of high damages, and evidences the poor TAC performance. d-ROMs and TAC assays could be useful for routine purposes; however, for an accurate clinical data evaluation, their comparison versus a \u201cgold standard method\u201d is required

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Validation of an HPLC-fluorescence method for the simultaneous free and glycosylated pyridinium crosslinks determination in urine

BACKGROUND: Pyridinium crosslinks, released during bone resorption, are excreted in urine as free pyridinoline (Pyr) and deoxypyridinoline (DPyr), or bound to peptide or to sugars, as galactosyl-pyridinoline (Gal-Pyr) and glucosyl-galactosyl pyridinoline (GluGal-Pyr). Commonly, only total Pyr and D-Pyr urinary amounts (free + bound forms) are evaluated. METHOD: We developed and validated an analytical method based on HPLC-fluorescence for the evaluation of the collagen crosslinks Pyr and DPyr (free and total), GluGal-Pyr and Gal-Pyr in the urine of healthy women (n = 20; aged 27-41) and girls (n = 20; aged 5-10). Urine, spiked with an unnatural D-Pyr homologue, as IS, was solid-phase extracted prior to HPLC analysis. The use of this IS and of pure Pyr, D-Pyr, GluGal-Pyr and Gal-Pyr, synthesized to be used as primary calibrators, guarantees the specificity of the method and the correct crosslinks quantification. Total Pyr and D-Pyr amounts were also evaluated after urine hydrolysis. RESULTS: The method demonstrates good selectivity, sensitivity, linearity, precision, accuracy, recovery and stability for all measured crosslinks. Pyr and D-Pyr, both free and total, and GluGal-Pyr amounts were significantly higher in girls than in women (p < 0.0001). Gal-Pyr, evaluated in girls for the first time, was under its lower quantification limit (< 21.20 pmol/mL) in women. CONCLUSIONS: The quantification of free and glycosylated pyridinium crosslinks might provide more information on the degradation of various types of collagen, respect to the measurement of total Pyr and D-Pyr alone. Moreover, this validated method could be a useful non-invasive technique for studying pathological conditions characterized by modified glycosylation enzyme activity and for other clinical investigations on bone fragility

Defining Mental and Behavioural Disorders in Genetically Determined Neurodevelopmental Syndromes with Particular Reference to Prader-Willi Syndrome

Genetically determined neurodevelopmental syndromes are frequently associated with a particular developmental trajectory, and with a cognitive profile and increased propensity to specific mental and behavioural disorders that are particular to, but not necessarily unique to the syndrome. How should these mental and behavioural disorders best be conceptualised given that similar symptoms are included in the definition of different mental disorders as listed in DSM-5 and ICD-10? In addition, a different conceptual framework, that of applied behavioural analysis, has been used to inform interventions for what are termed &lsquo;challenging behaviours&rsquo; in contrast to types of interventions for those conditions meeting diagnostic criteria for a &lsquo;mental disorder&rsquo;. These syndrome-specific developmental profiles and associated co-morbidities must be a direct or indirect consequence of the genetic abnormality associated with that syndrome, but the genetic loci associated with the syndrome may not be involved in the aetiology of similar symptoms in the general population. This being so, should we expect underlying brain mechanisms and treatments for specific psychopathology in one group to be effective in the other? Using Prader-Willi syndrome as an example, we propose that the conceptual thinking that informed the development of the Research Domain Criteria provides a model for taxonomy of psychiatric and behavioural disorders in genetically determined neurodevelopmental syndromes. This model brings together diagnostic, psychological and developmental approaches with the aim of matching specific behaviours to identifiable neural mechanisms

Development of a multianalyte method for the determination of anabolic hormones in bovine urine by isotope-dilution GC-MS/MS

A sensitive, specific and selective multianalyte GC\u2013MS/MS method has been developed for the determination of 11 anabolic hormones in bovine urine. After adjusting the urine pH to 4.8, the samples were spiked with deuterated internal standards and submitted to enzymatic hydrolysis with \u3b2-glucuronidase/arylsulfatase. Hormones were eluted with methanol through a C18 solid phase cartridge and submitted to a liquid\u2013liquid extraction. Analytes were derivatized by adding N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane and GC\u2013MS data were obtained in the positive electron impact tandem mass mode. Under these conditions, no matrix effects were observed and limit of detection values were in the range of 0.005 ng/mL (diethylstilbestrol) to 0.38 ng/mL (17\u3b1-methyltestosterone and 17\u3b1-ethynylestradiol). Recoveries from 81% (\u3b1-zeranol) to 149% (17\u3b1-methyltestosterone) were found under the selected conditions. These results were better than those found using heptafluorobutyric anhydride (HFBA) as derivative reagent and those measured in full scan and selective ion monitoring modes

Simultaneous free and glycosylated pyridinium crosslink determination in urine : Validation of an HPLC-fluorescence method using a deoxypyridinoline homologue as internal standard

Pyridinoline (Pyr), deoxypyridinoline (D-Pyr), galactosyl-pyridinoline (Gal-Pyr) and glucosyl\u2013galactosyl pyridinoline (GluGal-Pyr) are enzymatic mature pyridinium crosslinks. Generally, only total Pyr and DPyr urinary amounts (free + bound forms) are evaluated by HPLC as indices of bone resorption. This report describes the validation of an HPLC-fluorescence method for the simultaneous evaluation of free Pyr and D-Pyr, together with GluGal-Pyr and Gal-Pyr, in urine of healthy women (n = 20, aged 27\u201341) and girls (n = 20, aged 5\u201310). The use of an unnatural D-Pyr homologue, here proposed for the first time as internal standard, and of pure Pyr, D-Pyr, GluGal-Pyr and Gal-Pyr synthesized to be used as primary calibrators,guarantees method specificity and correct crosslink quantification. Urine, spiked with IS, was solid-phase extracted prior to HPLC analysis. Total Pyr and D-Pyr amounts were also evaluated after urine hydrolysis. The HPLC method was validated for selectivity, sensitivity, linearity, precision, accuracy, recovery and stability for all measured crosslinks. Both free and total Pyr and D-Pyr as well as GluGal-Pyr and Gal-Pyr amounts were significantly higher in girls than in women (p < 0.0001), indicating an increased collagen turnover rather than only bone turnover. Gal-Pyr, for the first time evaluated in girls, was under its lower quantification limit (<LLOQ, <21.20 pmol/mL) in women. The measurement of free and glycosylated pyridinium crosslinks might provide more information on the degradation of various types of collagen than only that of total Pyr and D-Pyr. Moreover, this validated method could be a useful non-invasive technique for studying pathological conditions characterized by modified glycosylation enzyme activity and for more clinical investigation on bone fragility

Dimethylarginines in complicated type 1 diabetes: roles of insulin, glucose, and oxidative stress

To investigate the roles of insulin, glucose, and oxidative stress on plasma asymmetric and symmetric dimethylarginine (ADMA, SDMA) levels in complicated diabetes, we studied patients with type 1 diabetes (T1D; n = 20), T1D + end-stage renal disease under hemodialysis (T1D + ESRD; n = 12), T1D + ESRD who received kidney transplant (KD; n = 16), and T1D + ESRD who received kidney-pancreas transplant (KP; n = 20) and healthy controls (n = 50). Levels of ADMA, SDMA, and free and total malondialdehyde (MDA) were increased in all patients, with the highest rises for SDMA and free MDA in T1D+ESRD. In KP, the normalized glycemia contributes to the recovery of ADMA, SDMA, and MDA levels toward normal values. From the covariance analyses, both glucose and insulin relate significantly to ADMA in T1D + ESRD (beta = +0.004, beta = -0.038, respectively) and in KP (beta = +0.032, beta = +0.032, respectively). Creatinine clearance and insulin relate to SDMA in all patient groups (beta = -0.006). Our results provide evidence for the effect of kidney-pancreas transplant on the recovery of ADMA, SDMA, and indexes of oxidative stress toward normal values. Only free MDA allows one to discriminate the magnitude of the oxidative status, as increased total MDA could also be attributable to a reduced renal function

Evaluation of oxidative status in human serum: comparison of different methodological approaches

Different biomarker assays have been developed for assessing oxidative stress in human serum. In this retrospective study the analytical performance of two different methodological approaches was evaluated in subjects with known increased oxidative stress to measure serum peroxidation indices: mild (n=35) and heavy (n=61) smokers, chronic renal failure (n=19) and kidney transplanted patients (n=59) compared to healthy controls (n=56). Serum oxidative stress, assessing Reactive Oxygen Metabolite derivatives (d-ROMs, Diacron International, Italy) levels and Total Antioxidant Capacity (TAC, Diacron International, Italy) by commercial spectrophotometric assays, was compared with malondialdehyde (MDA) concentrations, quantified both in free (FMDA) and total (T-MDA) forms, by isotope-dilution gas chromatography-mass spectrometry (GC-MS) technique (\u201cgold standard\u201d reference method), generally unsuitable for routine use. Sensitivity, specificity and cut-off points of T-MDA and F-MDA, d-ROMs, TAC assays were evaluated by receiver-operator characteristic (ROC) analyses together with the area under ROC curve (AUC). ROC analyses accuracy: the best for T-MDA (AUC: 1; sensitivity and specificity: 100%), good for d-ROMs (AUC: 0.87; sensitivity 72.8%, specificity: 100%) and F-MDA (AUC: 0.82; sensitivity 74.7%, specificity: 100%), and not as good as the previous for TAC (AUC: 0.66; sensitivity: 52% and specificity: 92.9%). The increased peroxidative damage was best proved only by T-MDA levels. The assessment of d-ROMS concentrations and TAC by reliable assays is useful for routine clinical purposes; even if less sensitive, it determines the balance of oxidative status. The comparison between \u201cgold standard\u201d and routine methods allows biochemists and clinicians to evaluate data more thorough