The prevalence of pulmonary embolism in non-hospitalised de-isolated patients diagnosed with mild COVID-19 disease

Background. Pulmonary embolism (PE) is a known complication of COVID-19 disease. The mechanism of thromboembolic events appears to be stimulated by excessive thrombin production, inhibition of fibrinolysis and deposition of antiphospholipids and thrombi, as well as microvascular dysfunction in multiple vascular beds. The occurrence of PE has been well demonstrated in hospitalised patients with severe disease. Very few data are available on its incidence or prevalence in non-hospitalised patients diagnosed with a milder form of the disease.Objectives. To assess the prevalence of PE in non-hospitalised patients diagnosed with mild COVID-19 who presented with raised D-dimer levels and persistent or new-onset cardiopulmonary symptoms.Methods. This was a retrospective study conducted in the Department of Nuclear Medicine at Universitas Academic Hospital, Bloemfontein, South Africa. We reviewed the studies of 65 non-hospitalised patients with COVID-19 referred to the department from July 2020 to January 2021 for a perfusion-only single-photon emission computed tomography/computed tomography (SPECT/CT) study or a ventilation/perfusion (VQ) SPECT/CT study. All 65 patients had raised D-dimer levels with persistent, worsening or new-onset cardiopulmonary symptoms after the diagnosis of COVID-19.Results. Sixty-five patients were studied. The median (interquartile range) age was 46 (41 - 54) years and the majority (88.2%) were female. There were 22 patients (33.8%) with lung perfusion defects in keeping with PE. Two of these patients had a false-negative computed tomography pulmonary angiography (CTPA) study for PE performed the same day as their VQ SPECT/CT study.Conclusions. We confirm a high prevalence of PE in non-hospitalised patients diagnosed with mild COVID-19 who presented with raised D-dimer levels and persistent or new-onset cardiopulmonary symptoms. We recommend that irrespective of disease severity, hospitalised and non-hospitalised patients with COVID-19 presenting with persistent or new-onset cardiopulmonary symptoms and raised D-dimer levels should be investigated further for PE.

Audit of surgical procedures in regional and central hospitals in Limpopo Province, South Africa

Background. There is a paucity of data on the functioning and surgical procedures performed in rural hospitals in South Africa.Objective. To determine the category of procedures performed at regional and tertiary hospitals in Limpopo Province, South Africa. Method. We conducted a retrospective analysis of surgical procedures performed in the regional and tertiary hospitals in Limpopo Province during a 1-year period from 1 March 2019 to 29 February 2020.Results. A total of 24 263 surgical procedures were performed during the study period. More than half of all cases (50.4%; n=12 252) were operated on at the tertiary hospitals while regional hospitals performed the remaining 12 011 operations.Conclusion. There is a great necessity to alleviate the central hospitals from the bulk of surgical procedures

LANDFORM PERCEPTION ACCURACY IN SHADED RELIEF MAPS: A REPLICATION STUDY CONFIRMS THAT NNW LIGHTING IS BETTER THAN NW AGAINST THE RELIEF INVERSION EFFECT

Relief inversion effect is a perceptual phenomenon that leads to an inverted perception of convex and concave shapes. This perceptual inversion occurs in scenes where the shading/shadows act as the main depth cue. In visuospatial displays, such as shaded relief maps, the positioning of the shadows in the northern slopes, thus when light source placed broadly in south, mislead the cognitive system based on the ‘light from above prior’ assumption (Mamassian and Goutcher 2001). Thus, assuming the light must come from above, our mind creates an illusion, and we perceive the landforms incorrectly. To judge the 3D spatial relationships in terrain representations correctly, the relief inversion effect must be avoided. Cartographic convention against this effect is to place the light source at northwest (NW), whereas a recent study demonstrated that north-north-west (NNW), or even north yields more precise results (Biland and Çöltekin, 2016). Since this finding goes against decades of convention, to establish its validity further, we attempted replicating the results with a different sample in South Africa. In this paper, we present our findings, which broadly confirm that the NNW (or also N) is better than NW against the relief inversion effect

Investigation of thiol levels in young commercial South African Sauvignon Blanc and Chenin Blanc wines using propiolate derivatization and GC-MS/MS

CITATION: Coetzee, C. et al. 2018. Investigation of thiol levels in young commercial South African Sauvignon Blanc and Chenin Blanc wines using propiolate derivatization and GC-MS/MS. South African Journal of Enology and Viticulture, 39(2):180-184, doi:10.21548/39-2-2683.The original publication is available at https://www.journals.ac.za/index.php/sajevIn this work, the ethyl propiolate method for analysing thiols in white wine by GC-MS, originally proposed by Herbst-Johnstone et al.) (2013), has been adapted to GC-MS/MS and has been validated. The method performance has shown improvement in terms of sensitivity (limit of detection, LOD) and of the number of compounds measured. In addition to 3-mercaptohexanol (3MH), 3-mercaptohexyl acetate (3MHA), and 4-mercapto-4-methylpentan-2-one (4MMP), the adapted method can also measure 2-furanmethanethiol (FMT) and makes use of a commercially-available internal standard (IS), 4-methoxy-2-methyl-2-butanethiol (4M2M2B, IS). The proposed method was applied to determine thiol levels in young commercial South African Sauvignon and Chenin Blanc wines. The samples (n=20 for each cultivar) were chosen according to a high frequency of the typical descriptors associated with this class of impact compounds. 3MH was found at 178-904 ng/L and 99-1124 ng/L, and 3MHA at 23-151 ng/L and 5-253 ng/L in Sauvignon and Chenin Blanc respectively. 4MMP was present in Sauvignon Blanc in concentrations up to 21.9 ng/L, but in none of the Chenin Blanc samples.https://www.journals.ac.za/index.php/sajev/article/view/2683Publisher's versio

The role of locus of control in nyaope addiction treatment

Background: Nyaope addiction is a significant health and social problem affecting some South African communities. With reported nyaope rehabilitation success rates of less than 3% and estimated dropout rates of 40%, improvement in the rehabilitation rates is essential. As locus of control (LOC) is a recognised predictive factor in the onset of substance use and rehabilitation outcomes, a rehabilitation programme aligned to the LOC orientation of the user could result in improved recovery outcomes. This study aimed to determine the LOC of nyaope users.Methods: Consenting adult male and female nyaope users voluntary participated in this quantitative study. After convenient sampling, 115 nyaope users admitted to drug rehabilitation centres registered and funded by the Gauteng Department of Social Development and 106 nyaope users from the streets of urban areas of Tshwane completed a self-administered validated questionnaire. LOC orientation was determined by giving participants 13 statements from which they had to choose the option that best described their situation in relation to drug addiction.Results: A total of 24.5% (47/192) of the respondents could be classified as having an external LOC orientation while 75.5% (145/192) were classified as having an internal LOC orientation.Conclusions: By determining the LOC orientation of a nyaope user, rehabilitation programmes could be aligned to suit the personality of the user leading to a better chance of successful recovery with fewer cases of readmission

Potentially smoke tainted red wines: volatile phenols and aroma attributes

CITATION: McKay, M., et al. 2019. Potentially smoke tainted red wines : volatile phenols and aroma attributes. South African Journal of Enology and Viticulture, 40(2), doi:10.21548/40-2-3270.The original publication is available at http://www.journals.ac.za/index.php/sajevMalodourous compounds, including volatile phenols (VPs) are frequently found at concentrations below their odour thresholds in wine, and may therefore be considered to present no threat to wine quality. Most investigations into smoke taint quantify compounds by chemical/analytical means, or investigate sensory effects of supra- and peri-threshold contamination in model wine. In this project, twelve wines submitted by the South African industry as ‘faulty’ and/or smoke tainted were screened for VPs using GC-MS, and characterized using Descriptive Analysis (DA) by a sensory panel highly trained in smoke taint evaluation. Results were compared statistically to elucidate relationships between chemical and sensory characteristics. It was demonstrated, using the combined dataset, that concentration and composition of VPs in the wines correlated well with certain sensory attributes. Guaiacol was present in most samples at peri- or supra-threshold levels, but did not cause taint unless in combination with other phenols, when it was associated with ‘smoky’, ‘ashy’ and ‘herbaceous’ attributes. Wines with very low levels of VPs showed more sweet-associated aroma characteristics. Wines with supra-threshold levels of VPs showed negative attributes (‘chemical/plastic’, ‘tar/BR’ and ‘medicinal/Elastoplast™’). In some cases, sensory effects (‘earthy/dusty/potato skin’, ‘mouldy/musty’ and ‘cooked veg’) could not be attributed to peri- or supra-threshold concentrations, but seemed to be due to combinations of volatile phenols at subthreshold levels. Associations between negative attributes and historical bushfire events prior to harvest were found for a number of the wines. This study emphasizes the importance of understanding effects of VPs on wine aroma, and escalating awareness and sensitivity to these issues in the wine industry.https://www.journals.ac.za/index.php/sajev/article/view/3270Publisher's versio

Determination of volatile phenol in cabernet sauvignon wines, made from smoke-affected grapes, by using HS-SPME GC-MS

CITATION: De Vries, C. J., et al. 2016. Determination of volatile phenol in cabernet sauvignon wines, made from smoke-affected grapes, by using HS-SPME GC-MS. South African Journal for Enology and Viticulture, 37(1): 15-21, doi:10.21548/37-1-754.The original publication is available at http://www.journals.ac.zaThe increased incidence of vegetation fires near vineyards in the Western Cape, South Africa has led to growing concern over the appearance of smoke taint in the affected grapes. This study focused on the effect of smoke exposure on the volatile phenol (VP) composition of wines made from affected grapes over two vintages (2012 and 2013). Cabernet Sauvignon grapes were exposed, 10 days post-véraison, to a single, hour-long treatment with smoke derived from burning a mixture of vegetation (including fynbos) under controlled conditions in enclosures. Enclosures were sealed for 24 h after exposure, and then removed. Grapes were allowed to ripen and wines were then produced. Wines were analysed by headspace gas chromatography mass spectrometry (HS-SPME GC-MS) for selected volatiles. The results of the investigation show that the exposure of grapes to smoke during ripening leads to the accumulation of VPs that were detected in wines. The detected VPs were guaiacol, phenol and the cresols. Smoke exposure of grapes during ripening may have a negative impact on wine quality due to the accumulation of these compounds.http://www.journals.ac.za/index.php/sajev/article/view/754Publisher's versio