Estimating the burden of disease attributable to ambient air pollution (ambient PM2.5 and ambient ozone) in South Africa for 2000, 2006 and 2012.

Background: Globally, a growing body of research has shown that ambient air pollution is one of the most critical environmental issues, especially in relation to human health. Exposure to ambient air pollution leads to serious health conditions such as lower respiratory infections, cancers, diabetes mellitus type 2, ischaemic heart disease, stroke and chronic obstructive pulmonary disease. Objectives: To estimate the burden of disease attributable to ambient air pollution in South Africa (SA) for the years 2000, 2006 and 2012. Methods: Comparative risk assessment method was used to determine the burden of disease due to two pollutants (particulate matter (PM2.5) and ambient ozone). Regionally optimised fully coupled climate chemistry models and surface air pollution observations were used to generate concentrations of PM2.5 and ozone for each SA Census Small Area Level, for the year 2012. For 2000 and 2006, population-weighted PM2.5and ozone were estimated, based on the 2012 results. Following the identification of disease outcomes associated with particulate matter with aerodynamic diameter <2.5 µm (PM2.5) and ozone exposure, the attributable burden of disease was estimated for 2000, 2006 and 2012. Furthermore, for the year 2012, the burden of disease attributable to ambient air pollution exposure was computed at provincial levels. Results: In 2012, approximately 97.6% of people in SA were exposed to PM2.5 at levels above the 2005 World Health Organization guideline: 10 µg/m3 annual mean. From 2000 to 2012, population-weighted annual average PM2.5 increased from 26.6 µg/m3 to 29.7 µg/m3, and ozone 6-month high 8-hour daily maximum increased from 64.4 parts per billion (ppb) to 72.1 ppb. At a national scale, in the year 2000, 15 619 (95% uncertainty interval (UI) 8 958 - 21 849) deaths were attributed to PM2.5 exposure, while 1 326 (95% UI 534 - 1 885) deaths were attributed to ozone. In 2006, an estimated 19 672 deaths (95% UI 11 526 - 27 086) were attributed to PM2.5, and a further 1 591 deaths (95% UI 651 - 2 236) to ozone exposure. In 2012, deaths attributed to PM2.5 were 19 507 (95% UI 11 318 - 27 111), and to ozone 1 734 (95% UI 727 - 2 399). Additionally, population-weighted provincial scale analysis showed that Gauteng Province had the highest number of attributable deaths due to both PM2.5 and ozone in 2012. Conclusion: The study showed that ambient air pollution exposure is an important health risk in SA, requiring both short- and long-term intervention. In the short term, the SA Ambient Air Quality Standards and industrial minimum emissions standards need to be enforced. In the longer term, to reduce air pollution and the associated disease burden, the combustion of fossil fuels as a source of energy for power generation and transportation, as well as industrial and domestic uses, needs to be replaced with clean renewable energy sources. In addition to local measures, when the southern African prevalent anticyclonic air dynamics that transport regionally emitted pollutants into SA (especially from biomass burning) are considered, it is also advisable to establish long-term regional co-operation in reducing air pollution.

Determination of the ursolic and oleanolic acids content with the antioxidant capacity in apple peel extract of various cultivars.

Apples are rich sources of ursolic acid (UA) and oleanolic acid (OA) which are the major and most prominent triterpenes in the peel of an apple. Pentacyclic triterpenes are ideal nutraceuticals due to their ability to reduce the risk of many life-threatening diseases such as cancer, cardiovascular and diabetes. This study was to determine the content of UA and OA in the apple peel extract from different cultivars grown in South Africa as well as the correlation of their content level with antioxidant capacity. Quantitative analysis of UA and OA in apple peels from three cultivars; red delicious (RD), royal gala (RG) and granny smith (GS) apples was carried out using HPLC and their antioxidant capacity was analyzed using the DPPH assay. The RD showed the highest content of UA and OA (248.02 ± 0.08 µg/ml and 110.00 ± 0.08 µg/ml respectively) in the apple peel extract and also displayed a significantly high level of antioxidant capacity (97.3 ± 0.40%; p < 0.0001) compared to the RG and GS cultivars. A strong positive correlation was noted between the UA, OA and antioxidant capacities of all the cultivars. Only the RD cultivar showed a significant correlation though; UA (r = 0.9570; p = 0.0027) and OA (r = 0.8503; p = 0.0319). This study demonstrated that the RD and RG apple peels possess the highest UA and OA content which invariably increases their antioxidant activities compared to GS apple. Thus, both apple cultivars would be useful and recommended for food consumption and nutraceuticals values to improve human health.

Sentinel seroprevalence of SARS-CoV-2 in Gauteng Province, South Africa, August - October 2020.

BACKGROUND: Estimates of prevalence of anti-SARS-CoV-2 antibody positivity (seroprevalence) for tracking the COVID-19 epidemic are lacking for most African countries. OBJECTIVES: To determine the prevalence of antibodies against SARS-CoV-2 in a sentinel cohort of patient samples received for routine testing at tertiary laboratories in Johannesburg, South Africa. METHODS: This sentinel study was conducted using remnant serum samples received at three National Health Laboratory Service laboratories in the City of Johannesburg (CoJ) district. Collection was from 1 August to 31 October 2020. We extracted accompanying laboratory results for glycated haemoglobin (HbA1c), creatinine, HIV, viral load and CD4 T-cell count. An anti-SARS-CoV-2 targeting the nucleocapsid (N) protein of the coronavirus with higher affinity for IgM and IgG antibodies was used. We reported crude as well as population-weighted and test-adjusted seroprevalence. Multivariate logistic regression analysis was used to determine whether age, sex, HIV and diabetic status were associated with increased risk for seropositivity. RESULTS: A total of 6 477 samples were analysed, the majority (n=5 290) from the CoJ region. After excluding samples with no age or sex stated, the model population-weighted and test-adjusted seroprevalence for the CoJ (n=4 393) was 27.0% (95% confidence interval (CI) 25.4 - 28.6). Seroprevalence was highest in those aged 45 - 49 years (29.8%; 95% CI 25.5 - 35.0) and in those from the most densely populated areas of the CoJ. Risk for seropositivity was highest in those aged 18 - 49 years (adjusted odds ratio (aOR) 1.52; 95% CI 1.13 - 2.13; p=0.0005) and in samples from diabetics (aOR 1.36; 95% CI 1.13 - 1.63; p=0.001). CONCLUSIONS: Our study conducted between the first and second waves of the pandemic shows high levels of current infection among patients attending public health facilities in Gauteng Province.

The role of serological testing in the SARS-CoV-2 outbreak.

Antibody tests for the novel coronavirus, SARS-CoV2, have been developed both as rapid diagnostic assays and for high-throughput formal serology platforms. Although these tests may be a useful adjunct to a diagnostic strategy, they have a number of limitations. Because of the antibody and viral dynamics of the coronavirus, their sensitivity can be variable, especially at early time points after symptom onset. Additional data are required on the performance of the tests in the South African population, especially with regard to development and persistence of antibody responses and whether antibodies are protective against reinfection. These tests may, however, be useful in guiding the public health response, providing data for research (including seroprevalence surveys and vaccine initiatives) and development of therapeutic strategies.

The role of serological testing in the SARS-CoV-2 outbreak

Antibody tests for the novel coronavirus, SARS-CoV2, have been developed both as rapid diagnostic assays and for high-throughput formal serology platforms. Although these tests may be a useful adjunct to a diagnostic strategy, they have a number of limitations. Because of the antibody and viral dynamics of the coronavirus, their sensitivity can be variable, especially at early time points after symptom onset. Additional data are required on the performance of the tests in the South African population, especially with regard to development and persistence of antibody responses and whether antibodies are protective against reinfection. These tests may, however, be useful in guiding the public health response, providing data for research (including seroprevalence surveys and vaccine initiatives) and development of therapeutic strategies

Type 2 diabetes remission rates 1-year post-Roux-en-Y gastric bypass and validation of the DiaRem score: the Ontario Bariatric Network experience.

Roux-en-Y gastric bypass (RYGB) is associated with the remission of type 2 diabetes mellitus (DM). There are a number of scoring systems available that help predict type 2 diabetes remission rates after bariatric surgery; however, relatively few have been validated externally. The DiaRem score, comprised of four preoperative variables (age, haemoglobin A1c [HbA1c], sulfonylurea and insulin-sensitizing agent use and insulin use), allows for the identification of patients who are most likely to have DM remission following RYGB. Our primary objective was to determine the variables predictive of DM remission 1 year post-RYGB, determine how well the DiaRem score predicts DM remission 1 year post-RYGB and identify the optimal cut-off DiaRem score. The study is based on results of RYGB performed across multiple centres in Ontario, Canada, overseen by the Centre for Surgical Invention and Innovation in Hamilton, with direction from the Ontario Bariatric Network. Regression analysis was used to determine the predictive value of demographic and clinical variables and that of the DiaRem score. The optimal DiaRem cut-off score was determined using sensitivity and specificity analysis. Of 3874 patients in the Ontario Bariatric Registry between January 2010 and February 2015, 915 had complete 1-year follow-up data. Among these, 15 were not classified as having DM at baseline and were excluded. Of the remaining 900 patients with type 2 diabetes and who underwent RYGB surgery, 333 (37.0%) had DM remission at 1-year follow-up. Three of four DiaRem variables (age, HbA1c, insulin use), in addition to use of any hypoglycaemic agent, were associated with DM remission. DiaRem score had moderate predictive value. A DiaRem score cut-off of <5 had a sensitivity of 71.8% and specificity of 71.3%. This study provides guidance to clinicians in using the DiaRem score to inform the selection and prioritization of patients to ensure timely access to bariatric surgery for those who are likely to benefit the most.

Extraction studies of uranium(VI), plutonium(IV) and americium(III) from nitric acid using the bi-functional carbamoyl methyl sulfoxide ligands.

The extraction behavior of new bi-functional ligands containing sulfoxide and amide groups viz. N,N'-dibutyl carbamoyl methyl phenyl sulfoxide (L1) and N,N'-dibutyl carbamoyl methyl benzyl sulfoxide (L2) towards the U(VI), Pu(IV) and Am(III) ions from nitric acid was studied. Both of these extractants showed appreciable extractions for U(VI) and Pu(IV) from 1 to 9.5 M nitric acid concentrations. Am(III) did not show an appreciable extraction under the conditions studied. The species extracted from a nitric acid medium correspond to the compositions of [UO2(NO3)(2).2L] and [Pu(NO3)4.2L] for L1 and a mixture of [UO2(NO3)(2).2L], [UO2(NO3)2.L] and [Pu(NO3)(4).2L] for the L2. The conditional extraction constant (Kex) values for the Pu(IV) with L1 and L2 were estimated for the first time, and found to be 6.21 x 10(2) and 5.64 x 10(2) mol(-4) dm, respectively.

Comparative study of tympanoplasty in wet perforation v/s totally dry perforation in tubotympanic disease.

In our initial experience the failure rate in totally dry ear Tympanoplasty were more as compared to wet Tympanoplasty. Hence we suspected the avascularity of totally dry tympanic membrane is the cause for such failures. So we did histopathological study of both types of remnant tympanic membrane & compared the finding. According to the results we infer that graft take up rate is better in wet central perforation than totally dry perforation following tympanoplasty, so is the success rate. This also correlates with our clinical experience. We have further seen that such types of failures can he prevented, if(i) the central perforation is converted to subtotal perforation by removing the necrotic portion of the TM, (ii) stabilization of the underlay graft by antero-superior anchoring myringoplasty in which a window in the anterior canal skin is made at about 3 O'clock position in right ear & 9 O'clock position in left ear and the graft is tucked under it.

A safe and reliable technique in the management of preauricular sinus.

Preauricular sinus/pit is a common congenital malformation, which presents as a pit or depression at the anterior margin of the ascending margin of helix, adjacent to helicine crux, or adjacent to the tragus. It is inherited as an autosomal dominant incomplete pattern with variable power of expression. It is due to a defect in the auricular embyrogenesis, which results in the preauricular sinus or pit. It is closely related to the helical cartilage. Using local anaesthesia in adults an elliptical incision is made around the sinus, and extended to the postauricular area. Plane of temporalis fascia identified, skin anterior to the sinus is separated from the underlying soft tissue. The soft tissue between the plane of temporalis fascia and the skin anterior to the sinus is excised along with a piece of adjoining helical cartilage. With this method no recurrences were encountered.

Hemoptysis due to migration of a fractured Kirschner wire.

We report a rare complication related to the insertion of Kirschner wires for stabilization of an acromioclavicular separation. Five years after placement of the Kirschner wires, the patient presented with hemoptysis. On review of chest radiographs, a fractured wire was found to have migrated from the acromioclavicular joint, through the hemithorax and into the trachea.

Tumor necrosis factor receptor 2 plays a minor role for mycobacterial immunity.

Tumor necrosis factor (TNF) signalling via the TNF receptor 1 (TNF-R1) is required for host resistance to mycobacterial infection. The role of TNF-R2 in anti-mycobacterial immunity is not known. Therefore, we compared TNF-R1 and TNF-R2 knockout (KO) mice infected with Mycobacterium bovis BCG (10(7) CFU, i.v.). While the bacterial burden of TNF-R1-deficient mice was significantly increased and the mice succumbed to infection between 4 and 5 weeks, TNF-R2 KO mice were less sensitive, and only 3 of 10 mice died within 12 weeks. Wild-type (WT) mice were resistant to BCG infection. The inability to clear the infection of TNF-R1 KO mice was associated with a reduced delayed-type hypersensitivity (DTH) response to purified protein derivative and severe impairment in forming granulomas with reduced macrophage recruitment and activation, and diminished expression of adhesion molecules. By contrast, TNF-R2 KO mice developed normal DTH response and mature mycobactericidal granulomas as the WT mice. Therefore, anti-mycobacterial immunity is largely dependent on TNF signalling via the TNF-R1, while activation of TNF-R2 plays a minor role.

Refractory hypoxemia due to intrapulmonary shunting associated with bronchioloalveolar carcinoma.

Bronchioloalveolar carcinoma caused severe refractory hypoxemia due to intrapulmonary shunting in a patient. Preoperative evaluation by occlusion of the pulmonary lobar artery supplying the tumor showed normalization of the arterial oxygen saturation. Resection of the involved lobe corrected the intrapulmonary shunting, and the patient required no further supplemental oxygen. However, with recurrence of the tumor over the next 6 months the patient became progressively more hypoxemic and died.

Breathing pattern during acute respiratory failure and recovery.

The objective of this study was to compare the breathing pattern of patients who failed to wean from mechanical ventilation to the pattern during acute respiratory failure. We hypothesized that a similar breathing pattern occurs under both conditions. Breathing pattern, mouth occlusion pressure (P[0.1]) and maximum inspiratory pressure (P[I,max]) were measured in 15 patients during acute respiratory failure, within 24 h of the institution of mechanical ventilation, and in 49 patients during recovery, when they were ready for discontinuation from mechanical ventilation. The following indices were calculated: rapid shallow breathing index (respiratory frequency/tidal volume (fR/VT)); rapid shallow breathing-occlusion pressure index (ROP = P[0.1 x fR/VT]); P(0.1)/P(I,max); and effective inspiratory impedance (P[0.1]/VT/(inspiratory time (tI)). Patients who failed to wean (n=11) had a similar ROP,fR/VT and P(0.1)/P(I,max) to those with acute respiratory failure despite a significantly reduced P(0.1)/VT/tI, the value of which was comparable to that of patients who weaned successfully (n=38). The P(I,max) of patients who failed to wean was similar to that of patients who weaned successfully. We conclude that patients who failed to wean had a breathing pattern similar to that during acute respiratory failure, despite a reduced mechanical load on the respiratory muscles and a relatively adequate inspiratory muscle strength. This suggests that strategies that enhance respiratory muscle endurance may facilitate weaning.

Acute hemorrhagic leukoencephalitis during treatment for disseminated tuberculosis in a patient with AIDS.

A 45-year-old man with the acquired immune deficiency syndrome (AIDS) developed disseminated Mycobacterium tuberculosis infection and was started on isoniazid, rifampin, pyrazinamide and ethambutol. The treatment was interrupted because of side effects. On resumption of treatment be developed a rapidly progressive neurological illness characterized by left hemiparesis, right gaze preference, convulsions, coma, evidence of cerebral edema on computed tomography scan and death 9 days later. Autopsy showed the presence of miliary tuberculosis affecting the lungs, liver, spleen, lymph nodes and bone marrow. The brain showed evidence of acute hemorrhagic leukoencephalitis (AHL)-the first such case in a patient with AIDS. We speculate that treatment-induced lysis of mycobacteria with concomitant release of mycobacterial lipoproteins may have activated T-lymphocytes to cause AHL in this patient.

Resolution of recurrent atelectasis in spinal cord injury patients with administration of recombinant human DNase.

Atelectasis occurs frequently in patients with spinal cord injury (SCI). Impaired cough leads to ineffective clearance of secretions. If the secretions cannot be cleared and become thick and purulent, atelectasis may occur. Recombinant human DNase (rhDNase) has been shown to decrease purulent sputum viscosity in vitro. We report two SCI patients with respiratory failure due to recurrent atelectasis from purulent secretions in whom conventional treatment methods had failed. Administration of rhDNase resulted in successful resolution of atelectasis. These results suggest the need for a controlled clinical trial.

Lack of dietary calcium effect on chlordecone increased white blood cell count, total iron, and iron-binding capacity in serum of rat.

Male Sprague-Dawley rats were treated with 0, 1, 10, 50, and 100 ppm of chlordecone (Cd) mixed in calcium-sufficient (Ca-S) or calcium-deficient (Ca-D) diet for 15 days. The control rats fed with Ca-D diet exhibited a significant increase in white blood cell (WBC) counts compared to the rats fed with Ca-S diet. Dietary calcium (Ca), however, did not elicit any significant effect on total iron content and iron-binding capacity (transferrin) of control rats, whereas Cd at higher concentrations significantly increased WBC counts, total iron, and iron-binding capacity in serum of both Ca-S and Ca-D rats. The data suggest that dietary Ca did not alter Cd-increased WBC count, total iron, and iron-binding capacity in serum of rat.

An integrated analysis of health facilities in the nine provinces of South Africa.

The development of a comprehensive national health plan must take into account an analysis of the provision and distribution of health facilities. This study collected and verified data from a number of different sources, on the number and types of hospital beds, the number of fixed clinics, and the population sizes in each of the nine new provinces of South Africa. A comprehensive database of these figures was compiled for the years 1988 and 1993. Integrated analyses were made of the distribution and types of health facilities in South Africa by using population/facility ratios. Notable disparities were found to exist between provinces in the total (public and private) distribution of hospital beds per 1,000 population, but the distribution of acute hospital beds between provinces is more even. In provinces where there is more than one medical school, there is a marked imbalance between the levels of care, with greater emphasis placed on tertiary care, at the expense of the secondary level. Given the World Health Organisation recommendation of 10,000 people per clinic, there is a shortfall in most provinces. Recommendations are made with regard to the rationalisation of academic and referral beds, and the factors to be considered in the addressing of shortages of clinic facilities. However, the limitations of a resource-based planning approach must be recognised, and it is recommended that comprehensive analyses be carried out at regional and sub-regional levels to determine the appropriate delivery of health care.

Acquired laryngomalacia as a cause of obstructive sleep apnea.

We describe a patient who, 4 years after a radical neck dissection and radiotherapy, presented with obstructive sleep apnea; upon bronchoscopy, he was found to have acquired laryngomalacia. Inspiration induced upper airway obstruction due to a large flaccid epiglottis, large aryepiglottic folds, and edema of the supraglottic area. We suggest that acquired laryngomalacia can lead to obstructive sleep apnea. Patients with obstructive sleep apnea after radical neck dissection need to be evaluated for laryngomalacia with fiberoptic laryngobronchoscopy. Examination of the upper airway is useful to determine the nature and extent of any upper airway collapse.

Influence of dietary calcium on chlordecone-induced biochemical changes in serum of rat.

Male, Sprague-Dawley rats were treated with different (1, 10, 50, and 100 ppm) concentrations of chlordecone (Cd) in calcium-sufficient (Ca-S) or calcium-deficient (Ca-D) diet for 15 days. No significant changes in serum total proteins were observed. However, serum nonprotein nitrogen compounds (urea, uric acid, and creatinine) and glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, creatine kinase, and alkaline phosphatase were significantly increased at 50 and 100 ppm of Cd. Chlordecone induced more increase in these serum components of rats fed with Ca-D as compared to Ca-S diet. Increased serum nonprotein nitrogen compounds and enzymes indicate Cd-altered glomerular and hepatic functions.