Dissociative multi-photon ionization of isolated uracil and uracil-adenine complexes

Recent multi-photon ionization (MPI) experiments on uracil revealed a fragment ion at m/z 84 that was proposed as a potential marker for ring opening in the electronically excited neutral molecule. The present MPI measurements on deuterated uracil identify the fragment as C3H4N2O+ (uracil+ less CO), a plausible dissociative ionization product from the theoretically predicted open-ring isomer. Equivalent measurements on thymine do not reveal an analogous CO loss channel, suggesting greater stability of the excited DNA base. MPI and electron impact ionization experiments have been carried out on uracil-adenine clusters in order to better understand the radiation response of uracil within RNA. Evidence for C3H4N2O+ production from multi-photon-ionized uracil-adenine clusters is tentatively attributed to a significant population of π-stacked configurations in the neutral beam

Supplementary data for article: Tripkovic, T.; Charvy, C.; Alves, S.; Lolić, A.; Baošić, R.; Nikolić-Mandić, S. D.; Tabet, J. C. Identification of Protein Binders in Artworks by MALDI-TOF/TOF Tandem Mass Spectrometry. Talanta 2013, 113, 49–61. https://doi.org/10.1016/j.talanta.2013.03.071

Supplementary material for: [https://doi.org/10.1016/j.talanta.2013.03.071]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1366

Correlates of condom use in a sample of MSM in Ecuador

BACKGROUND: In Ecuador, the prevalence of HIV in the general population is approximately 0.3%. However, up to 17% prevalence has been reported among specific groups of homosexual and bisexual men. The objective of this study is to explore correlates of condom use among men who have sex with men (MSM) across eight cities in Ecuador. METHODS: A cross-sectional survey design was used. A questionnaire including variables on sexual behaviour, demographics, and socio-economic characteristics was distributed to a sample of MSM in eight Ecuadorian cities. RESULTS: Information was obtained for 2,594 MSM across the eight cities. The largest subcategory of self-identification was active bisexuals (35%), followed by those who described themselves as "hombrados" (masculine gays, 22%). The mean age was 25 years, and the majority were unmarried (78%), with a median of 10 years of schooling (IQR 7 – 12). Regarding condom use, 55% of those interviewed had unprotected penetrative sex with each of their last three partners, and almost 25% had never used a condom. The most important correlates of condom use were single status, high life-skills rating, and high socio-economic status (RP 5.45, 95% CI 4.26 – 6.37; RP 1.84, 95% CI 1.79 – 1.86, and RP 1.20, 95% CI 1.01 – 1.31, respectively). CONCLUSION: Our data illustrate the urgent need for targeted HIV-prevention programs for MSM populations in Ecuador. MSM have the highest HIV prevalence in the country, and condom use is extremely low. It is imperative that prevention strategies be re-evaluated and re-prioritized to more effectively respond to the Ecuadorian epidemic

Critical Review of Theoretical Models for Anomalous Effects (Cold Fusion) in Deuterated Metals

We briefly summarize the reported anomalous effects in deuterated metals at ambient temperature, commonly known as "Cold Fusion" (CF), with an emphasis on important experiments as well as the theoretical basis for the opposition to interpreting them as cold fusion. Then we critically examine more than 25 theoretical models for CF, including unusual nuclear and exotic chemical hypotheses. We conclude that they do not explain the data.Comment: 51 pages, 4 Figure

A pragmatic, multicentre, double-blind, placebo-controlled randomised trial to assess the safety, clinical and cost-effectiveness of mirtazapine and carbamazepine in people with Alzheimer’s disease and agitated behaviours: the HTA-SYMBAD trial

Background: Agitation is common and impacts negatively on people with dementia and carers. Non-drug patient-centred care is first-line treatment, but we need other treatment when this fails. Current evidence is sparse on safer and effective alternatives to antipsychotics. Objectives: To assess clinical and cost-effectiveness and safety of mirtazapine and carbamazepine in treating agitation in dementia. Design: Pragmatic, phase III, multicentre, double-blind, superiority, randomised, placebo-controlled trial of the clinical effectiveness of mirtazapine over 12 weeks (carbamazepine arm discontinued). Setting: Twenty-six UK secondary care centres. Participants: Eligibility: probable or possible Alzheimer’s disease, agitation unresponsive to non-drug treatment, Cohen-Mansfield Agitation Inventory score ≥ 45. Interventions: Mirtazapine (target 45 mg), carbamazepine (target 300 mg) and placebo. Outcome measures: Primary: Cohen-Mansfield Agitation Inventory score 12 weeks post randomisation. Main economic outcome evaluation: incremental cost per six-point difference in Cohen-Mansfield Agitation Inventory score at 12 weeks, from health and social care system perspective. Data from participants and informants at baseline, 6 and 12 weeks. Long-term follow-up Cohen-Mansfield Agitation Inventory data collected by telephone from informants at 6 and 12 months. Randomisation and blinding: Participants allocated 1: 1: 1 ratio (to discontinuation of the carbamazepine arm, 1: 1 thereafter) to receive placebo or carbamazepine or mirtazapine, with treatment as usual. Random allocation was block stratified by centre and residence type with random block lengths of three or six (after discontinuation of carbamazepine, two or four). Double-blind, with drug and placebo identically encapsulated. Referring clinicians, participants, trial management team and research workers who did assessments were masked to group allocation. Results: Two hundred and forty-four participants recruited and randomised (102 mirtazapine, 102 placebo, 40 carbamazepine). The carbamazepine arm was discontinued due to slow overall recruitment; carbamazepine/placebo analyses are therefore statistically underpowered and not detailed in the abstract. Mean difference placebo-mirtazapine (−1.74, 95% confidence interval −7.17 to 3.69; p = 0.53). Harms: The number of controls with adverse events (65/102, 64%) was similar to the mirtazapine group (67/102, 66%). However, there were more deaths in the mirtazapine group (n = 7) by week 16 than in the control group (n = 1). Post hoc analysis suggests this was of marginal statistical significance (p = 0.065); this difference did not persist at 6-and 12-month assessments. At 12 weeks, the costs of unpaid care by the dyadic carer were significantly higher in the mirtazapine than placebo group [difference: £1120 (95% confidence interval £56 to £2184)]. In the cost-effectiveness analyses, mean raw and adjusted outcome scores and costs of the complete cases samples showed no differences between groups. Limitations: Our study has four important potential limitations: (1) we dropped the proposed carbamazepine group; (2) the trial was not powered to investigate a mortality difference between the groups; (3) recruitment beyond February 2020, was constrained by the COVID-19 pandemic; and (4) generalisability is limited by recruitment of participants from old-age psychiatry services and care homes. Conclusions: The data suggest mirtazapine is not clinically or cost-effective (compared to placebo) for agitation in dementia. There is little reason to recommend mirtazapine for people with dementia with agitation. Future work: Effective and cost-effective management strategies for agitation in dementia are needed where non-pharmacological approaches are unsuccessful

Study of mirtazapine for agitated behaviours in dementia (SYMBAD): a randomised, double-blind, placebo-controlled trial

BACKGROUND: Agitation is common in people with dementia and negatively affects the quality of life of both people with dementia and carers. Non-drug patient-centred care is the first-line treatment, but there is a need for other treatment when this care is not effective. Current evidence is sparse on safer and effective alternatives to antipsychotics. We assessed the efficacy and safety of mirtazapine, an antidepressant prescribed for agitation in dementia. METHODS: This parallel-group, double-blind, placebo-controlled trial-the Study of Mirtazapine for Agitated Behaviours in Dementia trial (SYMBAD)-was done in 26 UK centres. Participants had probable or possible Alzheimer's disease, agitation unresponsive to non-drug treatment, and a Cohen-Mansfield Agitation Inventory (CMAI) score of 45 or more. They were randomly assigned (1:1) to receive either mirtazapine (titrated to 45 mg) or placebo. The primary outcome was reduction in CMAI score at 12 weeks. This trial is registered with ClinicalTrials.gov, NCT03031184, and ISRCTN17411897. FINDINGS: Between Jan 26, 2017, and March 6, 2020, 204 participants were recruited and randomised. Mean CMAI scores at 12 weeks were not significantly different between participants receiving mirtazapine and participants receiving placebo (adjusted mean difference -1·74, 95% CI -7·17 to 3·69; p=0·53). The number of controls with adverse events (65 [64%] of 102 controls) was similar to that in the mirtazapine group (67 [66%] of 102 participants receiving mirtazapine). However, there were more deaths in the mirtazapine group (n=7) by week 16 than in the control group (n=1), with post-hoc analysis suggesting this difference was of marginal statistical significance (p=0·065). INTERPRETATION: This trial found no benefit of mirtazapine compared with placebo, and we observed a potentially higher mortality with use of mirtazapine. The data from this study do not support using mirtazapine as a treatment for agitation in dementia. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme

Cost-effectiveness of mirtazapine for agitated behaviors in dementia: findings from a randomized controlled trial.

OBJECTIVES: To examine the costs and cost-effectiveness of mirtazapine compared to placebo over 12-week follow-up. DESIGN: Economic evaluation in a double-blind randomized controlled trial of mirtazapine vs. placebo. SETTING: Community settings and care homes in 26 UK centers. PARTICIPANTS: People with probable or possible Alzheimer's disease and agitation. MEASUREMENTS: Primary outcome included incremental cost of participants' health and social care per 6-point difference in CMAI score at 12 weeks. Secondary cost-utility analyses examined participants' and unpaid carers' gain in quality-adjusted life years (derived from EQ-5D-5L, DEMQOL-Proxy-U, and DEMQOL-U) from the health and social care and societal perspectives. RESULTS: One hundred and two participants were allocated to each group; 81 mirtazapine and 90 placebo participants completed a 12-week assessment (87 and 95, respectively, completed a 6-week assessment). Mirtazapine and placebo groups did not differ on mean CMAI scores or health and social care costs over the study period, before or after adjustment for center and living arrangement (independent living/care home). On the primary outcome, neither mirtazapine nor placebo could be considered a cost-effective strategy with a high level of confidence. Groups did not differ in terms of participant self- or proxy-rated or carer self-rated quality of life scores, health and social care or societal costs, before or after adjustment. CONCLUSIONS: On cost-effectiveness grounds, the use of mirtazapine cannot be recommended for agitated behaviors in people living with dementia. Effective and cost-effective medications for agitation in dementia remain to be identified in cases where non-pharmacological strategies for managing agitation have been unsuccessful