The antisaccade task as an index of sustained goal activation in working memory: modulation by nicotine

The antisaccade task provides a laboratory analogue of situations in which execution of the correct behavioural response requires the suppression of a more prepotent or habitual response. Errors (failures to inhibit a reflexive prosaccade towards a sudden onset target) are significantly increased in patients with damage to the dorsolateral prefrontal cortex and patients with schizophrenia. Recent models of antisaccade performance suggest that errors are more likely to occur when the intention to initiate an antisaccade is insufficiently activated within working memory. Nicotine has been shown to enhance specific working memory processes in healthy adults. MATERIALS AND METHODS: We explored the effect of nicotine on antisaccade performance in a large sample (N = 44) of young adult smokers. Minimally abstinent participants attended two test sessions and were asked to smoke one of their own cigarettes between baseline and retest during one session only. RESULTS AND CONCLUSION: Nicotine reduced antisaccade errors and correct antisaccade latencies if delivered before optimum performance levels are achieved, suggesting that nicotine supports the activation of intentions in working memory during task performance. The implications of this research for current theoretical accounts of antisaccade performance, and for interpreting the increased rate of antisaccade errors found in some psychiatric patient groups are discussed

Knowledge, Awareness and Practice with Antimicrobial Stewardship Programmes among Healthcare Providers in a Ghanaian Tertiary Hospital

Antimicrobial resistance (AMR) is a significant problem in global health today, particularly in low- and middle-income countries (LMICs) where antimicrobial stewardship programmes are yet to be successfully implemented. We established a partnership between AMR pharmacists from a UK NHS hospital and in Ho Teaching Hospital with the aim of enhancing antimicrobial stewardship knowledge and practice among healthcare providers through an educational intervention. We employed a mixed-method approach that included an initial survey on knowledge and awareness before and after training, followed by qualitative interviews with healthcare providers conducted six months after delivery of training. This study was carried out in two phases in Ho Teaching Hospital with healthcare professionals, including pharmacists, medical doctors, nurses and medical laboratory scientists. Ethical approval was obtained prior to data collection. In the first phase, we surveyed 50 healthcare providers, including nurses (33%), pharmacists (29%) and biomedical scientists (23%). Of these, 58% of participants had engaged in continuous professional development on AMR/AMS, and above 95% demonstrated good knowledge on the general use of antibiotics. A total of 18 participants, which included four medical doctors, five pharmacists, four nurses, two midwives and three biomedical scientists, were interviewed in the second phase and demonstrated greater awareness of AMS practices, particularly the role of education for patients, as well as healthcare professionals. We found that knowledge and practice with AMS was markedly improved six months after the training session. There is limited practice of AMS in LMICs; however, through AMR-focused training, we demonstrated improved AMS skills and practice among healthcare providers in Ho Teaching Hospital. There is a need for continuous AMR training sessions for healthcare professionals in resource-limited settings

Anticipating and addressing event-specific alcohol consumption among adolescents.

Background: Various specific events and celebrations are associated with excessive alcohol consumption and related harms. End-of-school celebrations such as Schoolies in Australia are of particular concern given high levels of documented harm among underage and young drinkers. The present study investigated high school students’ expectations of their Schoolies celebrations to inform future interventions to reduce adverse outcomes among members of this vulnerable group and other young people involved in similar rites of passage. Methods: A link to an online survey was distributed via high schools and Schoolies-related websites. The survey included qualitative questions that invited respondents to discuss (i) aspects of Schoolies they were looking forward to most and least and (ii) their perceptions of the likely consequences if they refrained from consuming alcohol during the event. In total, 435 students provided responses. Results: Respondents discussed the role of Schoolies in marking their transition to adulthood. Their comments revealed a cross-temporal focus indicating that Schoolies is simultaneously symbolic of the past, present, and future. Through its ability to enhance social interaction, alcohol was perceived to have a vital role in realising the potential of this event to signify and facilitate this temporal progression. Conclusions: Results suggest interventions that treat Schoolies as an isolated event that occurs in specific locations may fail to appreciate the extent to which these events transcend time for those involved. Instead, harm reduction is likely to involve a reconceptualisation of the event among both participants and authority figures to facilitate the provision of alternative pastimes to drinking during Schoolies that yield similar social benefits

Cortical thickness, surface area and volume measures in Parkinson's disease, multiple system atrophy and progressive supranuclear palsy

OBJECTIVE Parkinson's disease (PD), Multiple System Atrophy (MSA) and Progressive Supranuclear Palsy (PSP) are neurodegenerative diseases that can be difficult to distinguish clinically. The objective of the current study was to use surface-based analysis techniques to assess cortical thickness, surface area and grey matter volume to identify unique morphological patterns of cortical atrophy in PD, MSA and PSP and to relate these patterns of change to disease duration and clinical features. METHODS High resolution 3D T1-weighted MRI volumes were acquired from 14 PD patients, 18 MSA, 14 PSP and 19 healthy control participants. Cortical thickness, surface area and volume analyses were carried out using the automated surface-based analysis package FreeSurfer (version 5.1.0). Measures of disease severity and duration were assessed for correlation with cortical morphometric changes in each clinical group. RESULTS Results show that in PSP, widespread cortical thinning and volume loss occurs within the frontal lobe, particularly the superior frontal gyrus. In addition, PSP patients also displayed increased surface area in the pericalcarine. In comparison, PD and MSA did not display significant changes in cortical morphology. CONCLUSION These results demonstrate that patients with clinically established PSP exhibit distinct patterns of cortical atrophy, particularly affecting the frontal lobe. These results could be used in the future to develop a useful clinical application of MRI to distinguish PSP patients from PD and MSA patients

Development of a local antibiogram for a teaching hospital in Ghana

Background: Antimicrobial resistance threatens adequate healthcare provision against infectious diseases. Antibiograms, combined with patient clinical history, enable clinicians and pharmacists to select the best empirical treatments prior to culture results. Objectives: To develop a local antibiogram for the Ho Teaching Hospital. Methods: This was a retrospective cross-sectional study, using data collected on bacterial isolates from January-December 2021. Samples from urine, stool, sputum, blood, and cerebrospinal fluid (CSF) were considered as well as, aspirates and swabs from wound, ears and vagina of patients. Bacteria were cultured on both enrichment and selective media including blood agar supplemented with 5% sheep blood and MacConkey agar, and identified by both the VITEK 2 system and routine biochemical tests. Data on routine culture and sensitivity tests performed on bacterial isolates from patient samples were retrieved from the hospital's health information system. Data were then entered into and analysed using WHONET. Results: In all, 891 pathogenic microorganisms were isolated from 835 patients who had positive culture tests. Gram-negative isolates accounted for about 77% of the total bacterial species. Escherichia coli (246), Pseudomonas spp. (180), Klebsiella spp. (168), Citrobacter spp. (101) and Staphylococcus spp. (78) were the five most isolated pathogens. Most of the bacterial isolates showed high resistance (>70%) to ampicillin, piperacillin, ceftazidime, ceftriaxone, cefotaxime, penicillin G, amoxicillin, amoxicillin/clavulanic acid, ticarcillin/clavulanic acid and trimethoprim/sulfamethoxazole. Conclusions: The isolates from the various samples were not susceptible to most of the antibiotics used in the study. The study reveals the resistance patterns of E. coli and Klebsiella spp.To some antibiotics on the WHO 'Watch' and 'Reserve' lists. Using antibiograms as part of antimicrobial stewardship programmes would optimize antibiotic use and preserve their efficacy

Emergent global patterns of ecosystem structure and function from a mechanistic general ecosystem model

Anthropogenic activities are causing widespread degradation of ecosystems worldwide, threatening the ecosystem services upon which all human life depends. Improved understanding of this degradation is urgently needed to improve avoidance and mitigation measures. One tool to assist these efforts is predictive models of ecosystem structure and function that are mechanistic: based on fundamental ecological principles. Here we present the first mechanistic General Ecosystem Model (GEM) of ecosystem structure and function that is both global and applies in all terrestrial and marine environments. Functional forms and parameter values were derived from the theoretical and empirical literature where possible. Simulations of the fate of all organisms with body masses between 10 µg and 150,000 kg (a range of 14 orders of magnitude) across the globe led to emergent properties at individual (e.g., growth rate), community (e.g., biomass turnover rates), ecosystem (e.g., trophic pyramids), and macroecological scales (e.g., global patterns of trophic structure) that are in general agreement with current data and theory. These properties emerged from our encoding of the biology of, and interactions among, individual organisms without any direct constraints on the properties themselves. Our results indicate that ecologists have gathered sufficient information to begin to build realistic, global, and mechanistic models of ecosystems, capable of predicting a diverse range of ecosystem properties and their response to human pressures

Costs and Cost-Effectiveness of Training Traditional Birth Attendants to Reduce Neonatal Mortality in the Lufwanyama Neonatal Survival Study (LUNESP)

The Lufwanyama Neonatal Survival Project (“LUNESP”) was a cluster randomized, controlled trial that showed that training traditional birth attendants (TBAs) to perform interventions targeting birth asphyxia, hypothermia, and neonatal sepsis reduced all-cause neonatal mortality by 45%. This companion analysis was undertaken to analyze intervention costs and cost-effectiveness, and factors that might improve cost-effectiveness.We calculated LUNESP's financial and economic costs and the economic cost of implementation for a forecasted ten-year program (2011–2020). In each case, we calculated the incremental cost per death avoided and disability-adjusted life years (DALYs) averted in real 2011 US dollars. The forecasted 10-year program analysis included a base case as well as ‘conservative’ and ‘optimistic’ scenarios. Uncertainty was characterized using one-way sensitivity analyses and a multivariate probabilistic sensitivity analysis. The estimated financial and economic costs of LUNESP were $118,574 and$127,756, respectively, or $49,469 and$53,550 per year. Fixed costs accounted for nearly 90% of total costs. For the 10-year program, discounted total and annual program costs were $256,455 and$26,834 respectively; for the base case, optimistic, and conservative scenarios, the estimated cost per death avoided was $1,866,$591, and $3,024, and cost per DALY averted was$74, $24, and$120, respectively. Outcomes were robust to variations in local costs, but sensitive to variations in intervention effect size, number of births attended by TBAs, and the extent of foreign consultants' participation.Based on established guidelines, the strategy of using trained TBAs to reduce neonatal mortality was ‘highly cost effective’. We strongly recommend consideration of this approach for other remote rural populations with limited access to health care

Safety, Immunogenicity and Duration of Protection of the RTS,S/AS02D Malaria Vaccine: One Year Follow-Up of a Randomized Controlled Phase I/IIb Trial

The RTS,S/AS02(D) vaccine has been shown to have a promising safety profile, to be immunogenic and to confer protection against malaria in children and infants.We did a randomized, controlled, phase I/IIb trial of RTS,S/AS02(D) given at 10, 14 and 18 weeks of age staggered with routine immunization vaccines in 214 Mozambican infants. The study was double-blind until the young child completed 6 months of follow-up over which period vaccine efficacy against new Plasmodium falciparum infections was estimated at 65.9% (95% CI 42.6-79.8, p<0.0001). We now report safety, immunogenicity and estimated efficacy against clinical malaria up to 14 months after study start. Vaccine efficacy was assessed using Cox regression models. The frequency of serious adverse events was 32.7% in the RTS,S/AS02(D) and 31.8% in the control group. The geometric mean titers of anti-circumsporozoite antibodies declined from 199.9 to 7.3 EU/mL from one to 12 months post dose three of RTS,S/AS02(D), remaining 15-fold higher than in the control group. Vaccine efficacy against clinical malaria was 33% (95% CI: -4.3-56.9, p = 0.076) over 14 months of follow-up. The hazard rate of disease per 2-fold increase in anti-CS titters was reduced by 84% (95% CI 35.1-88.2, p = 0.003).The RTS,S/AS02(D) malaria vaccine administered to young infants has a good safety profile and remains efficacious over 14 months. A strong association between anti-CS antibodies and risk of clinical malaria has been described for the first time. The results also suggest a decrease of both anti-CS antibodies and vaccine efficacy over time.ClinicalTrials.gov NCT00197028

Alterations of brain and cerebellar proteomes linked to Aβ and tau pathology in a female triple-transgenic murine model of Alzheimer's disease

The triple-transgenic Alzheimer (3 × Tg-AD) mouse expresses mutant PS1M146V, APPswe, and tauP301L transgenes and progressively develops plaques and neurofibrillary tangles with a temporal- and region-specific profile that resembles the neuropathological progression of Alzheimer's disease (AD). In this study, we used proteomic approaches such as two-dimensional gel electrophoresis and mass spectrometry to investigate the alterations in protein expression occurring in the brain and cerebellum of 3 × Tg-AD and presenilin-1 (PS1) knock-in mice (animals that do not develop Aβ- or tau-dependent pathology nor cognitive decline and were used as control). Finally, using the Ingenuity Pathway Analysis we evaluated novel networks and molecular pathways involved in this AD model. We identified several differentially expressed spots and analysis of 3 × Tg-AD brains showed a significant downregulation of synaptic proteins that are involved in neurotransmitter synthesis, storage and release, as well as a set of proteins that are associated with cytoskeleton assembly and energy metabolism. Interestingly, in the cerebellum, a structure not affected by AD, we found an upregulation of proteins involved in carbohydrate metabolism and protein catabolism. Our findings help to unravel the pathogenic brain mechanisms set in motion by mutant amyloid precursor protein (APP) and hyperphosphorylated tau. These data also reveal cerebellar pathways that may be important to counteract the pathogenic actions of Aβ and tau, and ultimately offer novel targets for therapeutic intervention

Cortical Thinning in Patients with Recent Onset Post-Traumatic Stress Disorder after a Single Prolonged Trauma Exposure

Most of magnetic resonance imaging (MRI) studies about post-traumatic stress disorder (PTSD) focused primarily on measuring of small brain structure volume or regional brain volume changes. There were rare reports investigating cortical thickness alterations in recent onset PTSD. Recent advances in computational analysis made it possible to measure cortical thickness in a fully automatic way, along with voxel-based morphometry (VBM) that enables an exploration of global structural changes throughout the brain by applying statistical parametric mapping (SPM) to high-resolution MRI. In this paper, Laplacian method was utilized to estimate cortical thickness after automatic segmentation of gray matter from MR images under SPM. Then thickness maps were analyzed by SPM8. Comparison between 10 survivors from a mining disaster with recent onset PTSD and 10 survivors without PTSD from the same trauma indicates cortical thinning in the left parietal lobe, right inferior frontal gyrus, and right parahippocampal gyrus. The regional cortical thickness of the right inferior frontal gyrus showed a significant negative correlation with the CAPS score in the patients with PTSD. Our study suggests that shape-related cortical thickness analysis may be more sensitive than volumetric analysis to subtle alteration at early stage of PTSD