The prevalence of virus-B hepatitis South African blacks

The importance of virus-B as a cause of acute hepatitis in South African Blacks was determined by examining the serum of 147 patients during the acute stage of the illness for the presence of hepatitis-B antigen (HBAg). The antigen was found in 54% of 63 children and 65% of 83 adults with this disease. It is suggested that the relative predominance of virus-B hepatitis in Blacks is related to the high HBAg carrier rate in this population. The majority of patients with virus-B hepatitis did not give a history of parenteral exposure to the infectious agent, emphasising the importance of non·parenteral spread of virus-B.S. Afr. Med. J., 48, 1837 (1974)

Pharmacological characterisation of anti-inflammatory compounds in acute and chronic mouse models of cigarette smoke-induced inflammation

<p>Abstract</p> <p>Background</p> <p>Candidate compounds being developed to treat chronic obstructive pulmonary disease are typically assessed using either acute or chronic mouse smoking models; however, in both systems compounds have almost always been administered prophylactically. Our aim was to determine whether the prophylactic effects of reference anti-inflammatory compounds in acute mouse smoking models reflected their therapeutic effects in (more clinically relevant) chronic systems.</p> <p>Methods</p> <p>To do this, we started by examining the type of inflammatory cell infiltrate which occurred after acute (3 days) or chronic (12 weeks) cigarette smoke exposure (CSE) using female, C57BL/6 mice (n = 7-10). To compare the effects of anti-inflammatory compounds in these models, mice were exposed to either 3 days of CSE concomitant with compound dosing or 14 weeks of CSE with dosing beginning after week 12. Budesonide (1 mg kg^-1; i.n., q.d.), roflumilast (3 mg kg^-1; p.o., q.d.) and fluvastatin (2 mg kg^-1; p.o., b.i.d.) were dosed 1 h before (and 5 h after for fluvastatin) CSE. These dose levels were selected because they have previously been shown to be efficacious in mouse models of lung inflammation. Bronchoalveolar lavage fluid (BALF) leukocyte number was the primary endpoint in both models as this is also a primary endpoint in early clinical studies.</p> <p>Results</p> <p>To start, we confirmed that the inflammatory phenotypes were different after acute (3 days) versus chronic (12 weeks) CSE. The inflammation in the acute systems was predominantly neutrophilic, while in the more chronic CSE systems BALF neutrophils (PMNs), macrophage and lymphocyte numbers were all increased (p < 0.05). In the acute model, both roflumilast and fluvastatin reduced BALF PMNs (p < 0.01) after 3 days of CSE, while budesonide had no effect on BALF PMNs. In the chronic model, therapeutically administered fluvastatin reduced the numbers of PMNs and macrophages in the BALF (p ≤ 0.05), while budesonide had no effect on PMN or macrophage numbers, but did reduce BALF lymphocytes (p < 0.01). Roflumilast's inhibitory effects on inflammatory cell infiltrate were not statistically significant.</p> <p>Conclusions</p> <p>These results demonstrate that the acute, prophylactic systems can be used to identify compounds with therapeutic potential, but may not predict a compound's efficacy in chronic smoke exposure models.</p

Mental health inequalities in healthcare, economic, and housing disruption during COVID-19: an investigation in 12 longitudinal studies

Background: The COVID-19 pandemic and its associated virus suppression measures have disrupted lives and livelihoods, potentially exacerbating inequalities. People already experiencing mental ill-health may have been especially vulnerable to disruptions. / Aim: Investigate associations between pre-pandemic psychological distress and disruptions during the pandemic to (1) healthcare, economic activity, and housing, (2) cumulative disruptions and 3) whether these differ by age, sex, ethnicity or education. / Methods: Data were from 59,482 participants in 12 UK longitudinal adult population surveys with data collected both prior to and during the COVID-19 pandemic. Participants self-reported disruptions since the start of the pandemic to: healthcare (medication access, procedures, or appointments); economic activity (negative changes in employment, income or working hours); and housing (change of address or household composition). Logistic regression models were used within each study to estimate associations between pre-pandemic psychological distress scores and disruption outcomes. Findings were synthesised using a random effects meta-analysis with restricted maximum likelihood. / Results: Between one to two-thirds of study participants experienced at least one disruption during the pandemic, with 2.3-33.2% experiencing disruptions in 2 or more of the 3 domains examined. One standard deviation higher pre-pandemic psychological distress was associated with: (i) increased odds of any healthcare disruptions (OR=1.30; 95% CI: 1.20 to 1.40) with fully adjusted ORs ranging from 1.33 [1.20 to 1.49] for disruptions to prescriptions or medication access and 1.24 [1.09 to 1.41] for disruption to procedures; (ii) loss of employment (OR=1.13 [1.06 to 1.21]) and income (OR=1.12 [1.06 to 1.19]) and reductions in working hours/furlough (OR=1.05 [1.00 to 1.09]); (iii) no associations with housing disruptions (OR=1.00 [0.97 to 1.03]); and (iv) increased likelihood of experiencing a disruption in at least two domains (OR=1.25 [1.18 to 1.32]) or in one domain (OR=1.11 [1.07 to 1.16]) relative to experiencing no disruption. We did not find evidence of these associations differing by sex, ethnicity, education level, or age. / Conclusion: Those suffering from psychological distress before the pandemic were more likely to experience healthcare disruptions, economic disruptions related to unemployment and loss of income, and to clusters of disruptions across multiple domains during the pandemic. Considering mental ill-health was already unequally distributed in the UK population, the pandemic may exacerbate existing mental health inequalities. Individuals with poor mental health may need additional support to manage these pandemic-associated disruptions

Pre-pandemic mental health and disruptions to healthcare, economic and housing outcomes during the COVID-19 pandemic: evidence from 12 UK longitudinal studies

Background: The COVID-19 pandemic has disrupted lives and livelihoods, and people already experiencing mental ill health may have been especially vulnerable. / Aims: Quantify mental health inequalities in disruptions to healthcare, economic activity and housing. / Method: We examined data from 59 482 participants in 12 UK longitudinal studies with data collected before and during the COVID-19 pandemic. Within each study, we estimated the association between psychological distress assessed pre-pandemic and disruptions since the start of the pandemic to healthcare (medication access, procedures or appointments), economic activity (employment, income or working hours) and housing (change of address or household composition). Estimates were pooled across studies. / Results: Across the analysed data-sets, 28% to 77% of participants experienced at least one disruption, with 2.3–33.2% experiencing disruptions in two or more domains. We found 1 s.d. higher pre-pandemic psychological distress was associated with (a) increased odds of any healthcare disruptions (odds ratio (OR) 1.30, 95% CI 1.20–1.40), with fully adjusted odds ratios ranging from 1.24 (95% CI 1.09–1.41) for disruption to procedures to 1.33 (95% CI 1.20–1.49) for disruptions to prescriptions or medication access; (b) loss of employment (odds ratio 1.13, 95% CI 1.06–1.21) and income (OR 1.12, 95% CI 1.06 –1.19), and reductions in working hours/furlough (odds ratio 1.05, 95% CI 1.00–1.09) and (c) increased likelihood of experiencing a disruption in at least two domains (OR 1.25, 95% CI 1.18–1.32) or in one domain (OR 1.11, 95% CI 1.07–1.16), relative to no disruption. There were no associations with housing disruptions (OR 1.00, 95% CI 0.97–1.03). / Conclusions: People experiencing psychological distress pre-pandemic were more likely to experience healthcare and economic disruptions, and clusters of disruptions across multiple domains during the pandemic. Failing to address these disruptions risks further widening mental health inequalities

Vortices in polariton OPO superfluids

This chapter reviews the occurrence of quantised vortices in polariton fluids, primarily when polaritons are driven in the optical parametric oscillator (OPO) regime. We first review the OPO physics, together with both its analytical and numerical modelling, the latter being necessary for the description of finite size systems. Pattern formation is typical in systems driven away from equilibrium. Similarly, we find that uniform OPO solutions can be unstable to the spontaneous formation of quantised vortices. However, metastable vortices can only be injected externally into an otherwise stable symmetric state, and their persistence is due to the OPO superfluid properties. We discuss how the currents charactering an OPO play a crucial role in the occurrence and dynamics of both metastable and spontaneous vortices.Comment: 40 pages, 16 figure

Core components for effective infection prevention and control programmes: new WHO evidence-based recommendations

Abstract Health care-associated infections (HAI) are a major public health problem with a significant impact on morbidity, mortality and quality of life. They represent also an important economic burden to health systems worldwide. However, a large proportion of HAI are preventable through effective infection prevention and control (IPC) measures. Improvements in IPC at the national and facility level are critical for the successful containment of antimicrobial resistance and the prevention of HAI, including outbreaks of highly transmissible diseases through high quality care within the context of universal health coverage. Given the limited availability of IPC evidence-based guidance and standards, the World Health Organization (WHO) decided to prioritize the development of global recommendations on the core components of effective IPC programmes both at the national and acute health care facility level, based on systematic literature reviews and expert consensus. The aim of the guideline development process was to identify the evidence and evaluate its quality, consider patient values and preferences, resource implications, and the feasibility and acceptability of the recommendations. As a result, 11 recommendations and three good practice statements are presented here, including a summary of the supporting evidence, and form the substance of a new WHO IPC guideline

A qualitative study of the impact of severe asthma and its treatment showing that treatment burden is neglected in existing asthma assessment scales

Background People with severe asthma experience significant respiratory symptoms and suffer adverse effects of oral corticosteroids (OCS), including disturbed mood and physical symptoms. OCS impacts on health-related quality of life (HRQoL) have not been quantified. Asthma HRQoL scales are valid as outcome measures for patients requiring OCS only if they assess the deficits imposed by OCS. Aims The aim of this study was to compare the burden of disease and treatment in patients with severe asthma with items in eight asthma-specific HRQoL scales. Methods Twenty-three patients with severe asthma recruited from a severe asthma clinic were interviewed about the impact of their respiratory symptoms and the burden of their treatment. The domains from a thematic analysis of these interviews were compared with the items of eight asthma-specific HRQoL scales. Results In addition to the burden caused by symptoms, ten domains of OCS impact on HRQoL were identified: depression, irritability, sleep, hunger, weight, skin, gastric, pain, disease anxiety, and medication anxiety. Some patients experienced substantial HRQoL deficits attributed to OCS. Although all HRQoL scales include some OCS-relevant items, all eight scales fail to adequately assess the several types of burden experienced by some patients while on OCS. Conclusion The burden of OCS in severe asthma is neglected in policy and practice because it is not assessed in outcome studies. Existing asthma HRQoL scales provide an overly positive estimation of HRQoL in patients with frequent exposure to OCS and underestimate the benefit of interventions that reduce OCS exposure. Changes to existing measurement procedures are needed

A change in the optical polarization associated with a gamma-ray flare in the blazar 3C 279

It is widely accepted that strong and variable radiation detected over all accessible energy bands in a number of active galaxies arises from a relativistic, Doppler-boosted jet pointing close to our line of sight. The size of the emitting zone and the location of this region relative to the central supermassive black hole are, however, poorly known, with estimates ranging from light-hours to a light-year or more. Here we report the coincidence of a gamma-ray flare with a dramatic change of optical polarization angle. This provides evidence for co-spatiality of optical and gamma-ray emission regions and indicates a highly ordered jet magnetic field. The results also require a non-axisymmetric structure of the emission zone, implying a curved trajectory for the emitting material within the jet, with the dissipation region located at a considerable distance from the black hole, at about 10^5 gravitational radii.Comment: Published in Nature issued on 18 February 2010. Corresponding authors: Masaaki Hayashida and Greg Madejsk

Strategies to overcome physician shortages in northern Ontario: A study of policy implementation over 35 years

<p>Abstract</p> <p>Background</p> <p>Shortages and maldistibution of physicians in northern Ontario, Canada, have been a long-standing issue. This study seeks to document, in a chronological manner, the introduction of programmes intended to help solve the problem by the provincial government over a 35-year period and to examine several aspects of policy implementation, using these programmes as a case study.</p> <p>Methods</p> <p>A programme analysis approach was adopted to examine each of a broad range of programmes to determine its year of introduction, strategic category, complexity, time frame, and expected outcome. A chronology of programme initiation was constructed, on the basis of which an analysis was done to examine changes in strategies used by the provincial government from 1969 to 2004.</p> <p>Results</p> <p>Many programmes were introduced during the study period, which could be grouped into nine strategic categories. The range of policy instruments used became broader in later years. But conspicuous by their absence were programmes of a directive nature. Programmes introduced in more recent years tended to be more complex and were more likely to have a longer time perspective and pay more attention to physician retention. The study also discusses the choice of policy instruments and use of multiple strategies.</p> <p>Conclusion</p> <p>The findings suggest that an examination of a policy is incomplete if implementation has not been taken into consideration. The study has revealed a process of trial-and-error experimentation and an accumulation of past experience. The study sheds light on the intricate relationships between policy, policy implementation and use of policy instruments and programmes.</p

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns