Chronic obstructive pulmonary disease in South Africa: Under-recognised and undertreated

Chronic obstructive pulmonary disease (COPD) is acommon, preventable but incurable condition currentlyranked third in global mortality estimates. Worldwide,65 million people are estimated to have moderate to severeCOPD, and the disease accounts for 3 million deathsannually, of which 90% are said to occur in low- and middle-incomecountries. Yet, despite these staggering numbers, COPD remains bothunder-recognised and undertreated in most populations, also in SouthAfrica (SA). There are many reasons for this, not least of which isthe attitude of clinicians, which can often be fatalistic with regard toCOPD. This edition of CME highlights key aspects of the diagnosisand treatment – pharmacological and non-pharmacological –and new developments in the management of severe disease.Furthermore, we have included articles focusing on non-smokingrelatedCOPD and tips for good spirometry

Consent for critical care research after death from COVID-19: Arguments for a waiver

Pandemics challenge clinicians and scientists in many ways, especially when the virus is novel and disease expression becomes variable or unpredictable. Under such circumstances, research becomes critical to inform clinical care and protect future patients. Given that severely ill patients admitted to intensive care units are at high risk of mortality, establishing the cause of death at a histopathological level could prove invaluable in contributing to the understanding of COVID-19. Postmortem examination including autopsies would be optimal. However, in the context of high contagion and limited personal protective equipment, full autopsies are not being conducted in South Africa (SA). A compromise would require tissue biopsies and samples to be taken immediately after death to obtain diagnostic information, which could potentially guide care of future patients, or generate hypotheses for finding needed solutions. In the absence of an advance written directive (including a will or medical record) providing consent for postmortem research, proxy consent is the next best option. However, obtaining consent from distraught family members, under circumstances of legally mandated lockdown when strict infection control measures limit visitors in hospitals, is challenging. Their extreme vulnerability and emotional distress make full understanding of the rationale and consent process difficult either before or upon death of a family member. While it is morally distressing to convey a message of death telephonically, it is inhumane to request consent for urgent research in the same conversation. Careful balancing of the principles of autonomy, non-maleficence and justice becomes an ethical imperative. Under such circumstances, a waiver of consent, preferably followed by deferred proxy consent, granted by a research ethics committee in keeping with national ethics guidance and legislation, would fulfil the basic premise of care and research: first do no harm. This article examines the SA research ethics framework, guidance and legislation to justify support for a waiver of consent followed by deferred proxy consent, when possible, in urgent research after death to inform current and future care to contain the pandemic in the public interest

Pathogenesis of chronic obstructive pulmonary disease: An African perspective

The importance of chronic obstructive pulmonary disease (COPD) as a global health problem cannot be overstated. According to the latestWorld Health Organization statistics (2005), 210 million people suffer from COPD worldwide, and 5% of all deaths globally are estimated tobe caused by this disease. This corresponds to >3 million deaths annually, of which 90% are thought to occur in low- and middle-income countries.While cigarette smoking remains the major risk factor, and much of the increase in COPD is associated with projected increases in tobaccouse, epidemiological studies have demonstrated that in the majority of patients in developing countries the aetiology of COPD is multifactorial.This article summarises the epidemiology of and risk factors for COPD in Africa, including influences other than cigarette smoking thatare important contributors to chronic irreversible airflow limitation in our setting

Importance of food-demand management for climate mitigation

Recent studies show that current trends in yield improvement will not be sufficient to meet projected global food demand in 2050, and suggest that a further expansion of agricultural area will be required. However, agriculture is the main driver of losses of biodiversity and a major contributor to climate change and pollution, and so further expansion is undesirable. The usual proposed alternative - intensification with increased resource use - also has negative effects. It is therefore imperative to find ways to achieve global food security without expanding crop or pastureland and without increasing greenhouse gas emissions. Some authors have emphasised a role for sustainable intensification in closing global 'yield gaps' between the currently realised and potentially achievable yields. However, in this paper we use a transparent, data-driven model, to show that even if yield gaps are closed, the projected demand will drive further agricultural expansion. There are, however, options for reduction on the demand side that are rarely considered. In the second part of this paper we quantify the potential for demand-side mitigation options, and show that improved diets and decreases in food waste are essential to deliver emissions reductions, and to provide global food security in 2050.This work was funded by a grant to the University of Cambridge from BP as part of their Energy Sustainability Challenge.This is the accepted manuscript version. The final version is available from Nature Climate Change at http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2353.html

A severity-of-illness score in patients with tuberculosis requiring intensive care

Background. We previously retrospectively validated a 6-point severity-of-illness score aimed at identifying patients at risk of dying of tuberculosis (TB) in the intensive care unit (ICU). Parameters included septic shock, HIV infection with a CD4 count <200 cells/µL, renal dysfunction, a ratio of partial pressure of arterial oxygen to fraction of inspired oxygen (P/F) <200 mmHg, a chest radiograph demonstrating diffuse parenchymal infiltrates, and no TB treatment on admission.Objectives. To prospectively validate the severity-of-illness scoring system in patients with TB requiring intensive care, and to refine and simplify the score in order to expand its clinical utility.Methods. We performed a prospective observational study with a planned post hoc retrospective analysis, enrolling all adult patients with confirmed TB admitted to the medical ICU of a tertiary hospital in Cape Town, South Africa, from 1 February 2015 to 31 July 2018. The admission data of all adult patients with TB requiring admission to the ICU were used to calculate the 6-point severity-of-illness score and a refined 4-point score (based on the planned post hoc analysis). Descriptive statistics and χ2 or Fisher’s exact tests (where indicated) were performed on dichotomous categorical variables, and t-tests on continuous data. Patients were categorised as hospital survivors or non-survivors.Results. Forty-one of 78 patients (52.6%) died. The 6-point scores of non-survivors were higher than those of survivors (mean (standard deviation (SD)) 3.5 (1.3) v. 2.7 (1.2); p=0.01). A score ≥3 v. <3 was associated with increased mortality (64.0% v. 32.1%; odds ratio (OR) 3.75; 95% confidence interval (CI) 1.25 - 10.01; p=0.01). Post hoc, a P/F ratio <200 mmHg and no TB treatment on admission failed to predict mortality, whereas any immunosuppression did. A revised 4-point score (septic shock, any immunosuppression, acute kidney injury and lack of lobar consolidation) demonstrated higher scores in non-survivors than survivors (mean (SD) 2.8 (1.1) v. 1.6 (1.1); p<0.001). A score ≥3 v. ≤2 was associated with increased mortality (78.4% v. 29.3%; OR 8.76; 95% CI 3.12 - 24.59; p<0.001).Conclusions. The 6-point severity-of-illness score identified patients at increased risk of death. We were able to derive and retrospectively validate a simplified 4-point score with superior predictive power

Temperature dependence of electrical properties of electrodeposited Ni-based nanowires

The influence of annealing on the microstructure and the electrical properties of cylindrical nickel-based nanowires has been investigated. Nanowires of nickel of nominally 200 nm diameter and of permalloy (Py) of nominally 70 nm were fabricated by electrochemical deposition into nanoporous templates of polycarbonate and anodic alumina, respectively. Characterization was carried out on as-grown nanowires and nanowires heat treated at 650°C. Transmission electron microscopy and diffraction imaging of as-grown and annealed nanowires showed temperature-correlated grain growth of an initially nano-crystalline structure with ≤8 nm (Ni) and ≤20 nm (Py) grains towards coarser poly-crystallinity with grain sizes up to about 160 nm (Ni) and 70 nm (Py), latter being limited by the nanowire width. The electrical conductivity of individual as-grown and annealed Ni nanowires was measured in situ within a scanning electron microscope environment. At low current densities, the conductivity of annealed nanowires was estimated to have risen by a factor of about two over as-grown nanowires. We attribute this increase, at least in part, to the observed grain growth. The annealed nanowire was subsequently subjected to increasing current densities. Above 120 kA mm -2 the nanowire resistance started to rise. At 450 kA mm -2 the nanowire melted and current flow ceased

Reconstructing Sparticle Mass Spectra using Hadronic Decays

Most sparticle decay cascades envisaged at the Large Hadron Collider (LHC) involve hadronic decays of intermediate particles. We use state-of-the art techniques based on the \kt jet algorithm to reconstruct the resulting hadronic final states for simulated LHC events in a number of benchmark supersymmetric scenarios. In particular, we show that a general method of selecting preferentially boosted massive particles such as W, Z or Higgs bosons decaying to jets, using sub-jets found by the \kt algorithm, suppresses QCD backgrounds and thereby enhances the observability of signals that would otherwise be indistinct. Consequently, measurements of the supersymmetric mass spectrum at the per-cent level can be obtained from cascades including the hadronic decays of such massive intermediate bosons.Comment: 1+29 pages, 12 figure

Postpulmonary tuberculosis complications in South Africa and a potential link with pulmonary hypertension: Premise for clinical and scientific investigations

CITATION: Allwood, B. W. et al. 2018. Post-pulmonary tuberculosis complications in South Africa and a potential link with pulmonary hypertension : premise for clinical and scientific investigations. South African Medical Journal, 108(7):529, doi:10.7196/SAMJ.2018.v108i7.13359.The original publication is available at http://www.samj.org.zaThe magnitude of the pulmonary tuberculosis (TB) epidemic in South Africa (SA) and globally[1] has received increased attention. Efforts have been made to explore new and improved diagnostic[2] and treatment strategies,[3] but the story does not end with treatment, and TB frequently results in long-term lung damage.http://www.samj.org.za/index.php/samj/article/view/12339/8528Publisher's versio