165 research outputs found
Memory and attention while SCUBA diving at shallow and deep depths: An open water study
SCUBA diving requires a high level of cognitive functioning, however, many divers anecdotally report poor memory and attentional skills while underwater. Few studies have documented cognitive deficits resulting from an open-water dive. Here, 23 divers completed both shallow (8 m) and deep (28 m) dives over two days in the open-water. The order of the dives was counterbalanced across participants. While at depth, they completed the State-Trait Anxiety Inventory to assess anxiety levels, learned and were tested on a list of 36 words, and completed the trail making task (TMT) to assess executive functioning. They also gave saliva samples to measure cortisol levels before and after each dive and completed the Profile of Mood States survey after each dive on the boat. Divers remembered fewer words, took longer to complete the TMT, and exhibited higher cortisol levels following a deep dive; they reported no changes in anxiety or mood states. The results contribute to our understanding of how cognition is affected by pressurized environments and has implications for divers, as well as others who engage in high-altitude sports
Targeted HCV core antigen monitoring among HIV-positive men who have sex with men is cost-saving
Introduction: The World Health Organization declared the goal of hepatitis Cvirus (HCV) elimination by 2030. Micro-elimination, which is the reduction of incidence to zero in targeted populations, is less complex and costly and may be the first step to prove whether elimination is feasible. Asuitable target group are HIV-positive men who have sex with men (MSM) because of their high-risk behaviour and high incidence rates. Moreover, HCV monitoring is integrated in HIV care. The current HCV monitoring approach is suboptimal and complex and may miss new HCV infections. Alternative monitoring strategies, based on alanine aminotransferase, HCV-PCRand HCV-core antigen (HCV-cAg), combined with immediate direct-acting antiviral (DAA) treatment, may be more effective in reducing new HCV infections. Methods: Adeterministic mathematical transmission model was constructed representing the Dutch HCV epidemic among HIV-positive MSM to compare different HCV monitoring strategies from 2018 onwards. We evaluated the epidemiological impact of alternative and intensified monitoring in MSM with HCV. In addition, the cost-effectiveness was calculated over a lifetime horizon. Results: Current HCV monitoring and treatment is projected to result in an incidence of 1.1/1000 person-years, 0.24% prevalence, at a cost of 61.8 million (interquartile range 52.2-73.9). Compared with current monitoring, intensified monitoring will result in a maximum 27% reduction of incidence and 33% in prevalence at an increased cost. Conversely, compared with current monitoring, targeted HCV-cAg monitoring will result in a comparable incidence (1.1/1000 person-years) and prevalence (0.23%) but will be 1 million cheaper with increased quality-adjusted life year. Conclusion: Targeted monitoring reduces the HCV epidemic in a cost-saving manner; however, micro-elimination may not be obtained by 2030, highlighting the need for harm-reduction programmes
Dealing with missing standard deviation and mean values in meta-analysis of continuous outcomes: a systematic review
Background: Rigorous, informative meta-analyses rely on availability of appropriate summary statistics or individual
participant data. For continuous outcomes, especially those with naturally skewed distributions, summary
information on the mean or variability often goes unreported. While full reporting of original trial data is the ideal,
we sought to identify methods for handling unreported mean or variability summary statistics in meta-analysis.
Methods: We undertook two systematic literature reviews to identify methodological approaches used to deal with
missing mean or variability summary statistics. Five electronic databases were searched, in addition to the Cochrane
Colloquium abstract books and the Cochrane Statistics Methods Group mailing list archive. We also conducted cited
reference searching and emailed topic experts to identify recent methodological developments. Details recorded
included the description of the method, the information required to implement the method, any underlying
assumptions and whether the method could be readily applied in standard statistical software. We provided a
summary description of the methods identified, illustrating selected methods in example meta-analysis scenarios.
Results: For missing standard deviations (SDs), following screening of 503 articles, fifteen methods were identified in
addition to those reported in a previous review. These included Bayesian hierarchical modelling at the meta-analysis
level; summary statistic level imputation based on observed SD values from other trials in the meta-analysis; a practical
approximation based on the range; and algebraic estimation of the SD based on other summary statistics. Following
screening of 1124 articles for methods estimating the mean, one approximate Bayesian computation approach and
three papers based on alternative summary statistics were identified. Illustrative meta-analyses showed that when
replacing a missing SD the approximation using the range minimised loss of precision and generally performed better
than omitting trials. When estimating missing means, a formula using the median, lower quartile and upper quartile
performed best in preserving the precision of the meta-analysis findings, although in some scenarios, omitting trials
gave superior results.
Conclusions: Methods based on summary statistics (minimum, maximum, lower quartile, upper quartile, median)
reported in the literature facilitate more comprehensive inclusion of randomised controlled trials with missing mean or
variability summary statistics within meta-analyses
Hypertonic Saline Is Effective in the Prevention and Treatment of Mucus Obstruction, but Not Airway Inflammation, in Mice with Chronic Obstructive Lung Disease
Recent evidence suggests that inadequate hydration of airway surfaces is a common mechanism in the pathogenesis of airway mucus obstruction. Inhaled hypertonic saline (HS) induces osmotic water flux, improving hydration of airway surfaces. However, trials in patients with obstructive lung diseases are limited. The aim of this study was to investigate effects of HS on mucus obstruction and airway inflammation in the prevention and treatment of obstructive lung disease in vivo. We, therefore, used the β-epithelial Na+ channel (βENaC)–overexpressing mouse as a model of chronic obstructive lung disease and determined effects of preventive and late therapy with 3% HS and 7% HS on pulmonary mortality, airway mucus obstruction, and inflammation. We found that preventive treatment with 3% HS and 7% HS improved growth, reduced mortality, and reduced mucus obstruction in neonatal βENaC-overexpressing mice. In adult βENaC-overexpressing mice with chronic lung disease, mucus obstruction was significantly reduced by 7% HS, but not by 3% HS. Treatment with HS triggered airway inflammation with elevated keratinocyte chemoattractant levels and neutrophils in airways from wild-type mice, but reduced keratinocyte chemoattractant in chronic neutrophilic inflammation in adult βENaC-overexpressing mice. Our data demonstrate that airway surface rehydration with HS provides an effective preventive and late therapy of mucus obstruction with no consistent effects on inflammation in chronic lung disease. These results suggest that, through mucokinetic effects, HS may be beneficial for patients with a spectrum of obstructive lung diseases, and that additional strategies are required for effective treatment of associated airway inflammation
The global campaign to eliminate HBV and HCV infection: International Viral Hepatitis Elimination Meeting and core indicators for development towards the 2030 elimination goals
Hepatitis B virus (HBV) and hepatitis C virus (HCV) affect more than 320 million people worldwide, which is more than
HIV, tuberculosis (TB) and malaria combined. Elimination of HBV and HCV will, therefore, produce substantial public
health and economic benefits and, most importantly, the prevention of 1.2 million deaths per year. In 2016, member
states of the World Health Assembly unanimously adopted a resolution declaring that viral hepatitis should be eliminated
by 2030. Currently, few countries have elimination programmes in place and even though the tools to achieve elimination
are available, the right resources, commitments and allocations are lacking. During the fifth International Viral Hepatitis
Elimination Meeting (IVHEM), 7–8 December 2018, Amsterdam, the Netherlands, an expert panel of clinicians, virologists
and public health specialists discussed the current status of viral hepatitis elimination programmes across multiple
countries, challenges in achieving elimination and the core indicators for monitoring progress, approaches that have
failed and successful elimination plans
The European Prevalence of Resistance Associated Substitutions among Direct Acting Antiviral Failures
Background: Approximately 71 million people are still in need of direct-acting antiviral agents (DAAs). To achieve the World Health Organization Hepatitis C elimination goals, insight into the prevalence and influence of resistance associated substitutions (RAS) is of importance. Collaboration is key since DAA failure is rare and real-life data are scattered. We have established a European collaboration, HepCare, to perform in-depth analysis regarding RAS prevalence, patterns, and multiclass occurrence. Methods: Data were extracted from the HepCare cohort of patients who previously failed DAA therapy. Geno-and subtypes were provided by submitters and mostly based on in-house assays. They were reassessed using the Comet HCV subtyping tool. We considered RAS to be relevant if they were associated with DAA failure in vivo previously reported in literature. Results: We analyzed 938 patients who failed DAA therapy from ten different European countries. There were 239 genotypes (GT) 1a, 380 GT1b, 19 GT2c, 205 GT3a, 14 GT4a, and 68 GT4d infections. Several unusual subtypes (n = 15) (GT1b/g/l, GT3b, GT4k/n/r/t) were present. RAS appeared in over 80% of failures and over a quarter had three or more RAS. Multiclass RAS varied over target region and genotype between 0-48%. RAS patterns such as the Q30R + L31M and Q30R + Y93H in GT1a, the L31V + Y93H and L31V + Y93H for GT1b, and A30K + L31M and A30K/V + Y93H for GT3a all occurred with a prevalence below 5%. Conclusion: RAS occur frequently after DAA failures and follow a specific genotype and drug related pattern. Interpretation of the influence of RAS on retreatment is challenging due to various patterns, patients' characteristics, and previous treatment history. Moving towards HCV elimination, an ongoing resistance surveillance is essential to track the presence of RAS, RAS patterns and gather data for a re-treatment algorithm
Emergence and Persistence of Letermovir-Resistant Cytomegalovirus in a Patient with Primary Immunodeficiency
Background: Letermovir is a novel cytomegalovirus antiviral that is approved for prophylaxis in hematopoietic stem cell transplantation recipients Methods: After obtaining informed consent, letermovir prophylaxis was started in a patient with a presumed late-onset primary, combined T-and B-cell immunodeficiency. Plasma CMV DNAemia was monitored with real-time polymerase chain reaction, and letermovir resistance analyses were performed using Sanger sequencing and Illumina MiSeq next-generation sequencing. Results: A letermovir-resistant cytomegalovirus variant (C325Y mutation in UL56) emerged 17 weeks after start of prophylaxis. The letermovir-resistant variant was able to reactivate without drug selective pressure as this variant was again detected in plasma 20.6 weeks after stopping of letermovir. Conclusions: This case indicates that the C325Y mutation in UL56 does not significantly alter fitness of cytomegalovirus in vivo
Congenital hydrocephalus : new Mendelian mutations and evidence for oligogenic inheritance
Peer reviewe
Transmission of NS5A-Inhibitor Resistance-Associated Substitutions among Men Who Have Sex with Men Recently Infected with Hepatitis C Virus Genotype 1a
The transmission of direct-acting antiviral resistance-associated substitutions (RAS) could hamper hepatitis C virus (HCV) cure rates and elimination efforts. A phylogenetic analysis of 87 men who have sex with men recently infected with HCV genotype 1a placed one-third (28/87) in a large cluster, in which 96% harbored NS5A M28V RAS.</p
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