219 research outputs found
Peel and peel again
Aim: To determine if the internal limiting membrane (ILM) was present in the epiretinal membrane (ERM) when we deliberately tried to perform a "double peel" for macular pucker. Methods: Pars-plana vitrectomy and a "double peel" were carried out. The ERM and ILM were stained with Trypan Blue and peeled separately over the same area. The amount of ERM present in ILM specimens and the amount of ILM present in ERM specimens were evaluated by histological examination. Results: Seventeen eyes in 17 patients were included. It was possible to double peel in all cases. Five of 17 ERM specimens (29%) contained ILM fragments. When ILM was present on the ERM, it represented less than 50% of the sample. One ILM specimen was lost as result of an administrative error; of the remaining 16 specimens, residual ERM was found in six, and cellular remnants were observed on the vitreous surface in a further six of the ILMs. Clinically, no recurrence of ERM was found. Conclusion: ILM was present in some ERM specimens seemingly over the same area that an intact ILM was subsequently peel. We speculate that the ILM in the ERM represent a secondary basement membrane and that the surgical plane of dissection for most ERM peel is between the ERM and the native ILM, making it feasible to double peel routinely.published_or_final_versio
Measuring factors that can influence cattle supply response to the market in Namibia: Case study from Omaheke communal farmers
The study examined the factors that can influence the supply of cattle to the market in Namibia, with a specific focus on four communal areas of the Omaheke Region. A total of 100 cattle farmers were interviewed and the weighted least square (WLS) model was applied to analyse the data. The study found that the number of cattle owned, cost of production inputs, accessibility to market information, accessibility to local markets and rainfall have a strong influence on the sales volume. The study strongly recommends the formation of cattle marketing groups that can be employed to lower transaction cost, increase bargaining power, access to information and participation in formal markets. There is a need to improve access to institutions and to remove current distortions in the livestock marketing in Namibia. The study shows that there is an inverse relationship between source and information and volume of sales. When the barrier to source of information increases, the volume of sales decreases. The current policy advice should focus on the effects of policy distortions and adequate attention should be given to the serious, embedded institutional deficiencies that limit many communal farmers from taking advantage of market opportunities
Finding needles in haystacks: linking scientific names, reference specimens and molecular data for Fungi
DNA phylogenetic comparisons have shown that morphology-based species recognition often underestimates fungal diversity. Therefore, the need for accurate DNA sequence data, tied to both correct taxonomic names and clearly annotated specimen data, has never been greater. Furthermore, the growing number of molecular ecology and microbiome projects using high-throughput sequencing require fast and effective methods for en masse species assignments. In this article, we focus on selecting and re-annotating a set of marker reference sequences that represent each currently accepted order of Fungi. The particular focus is on sequences from the internal transcribed spacer region in the nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Re-annotated and verified sequences were deposited in a curated public database at the National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci (RTL) database, and will be visible during routine sequence similarity searches with NR_prefixed accession numbers. A set of standards and protocols is proposed to improve the data quality of new sequences, and we suggest how type and other reference sequences can be used to improve identification of Fungi
The Lingering Environmental Impact of Repressive Governance: The Environmental Legacy of the Apartheid Era for the New South Africa
This article aims to explore the historical link between contemporary environmental problems and the environmental, economic and political policies of the apartheid government. The analysis draws on an examination of the detrimental environmental impacts of the apartheid era and how international isolation impacted on governmental environmental management in the country, before turning attention to the way in which the ANC government has managed the South African natural and human environments in the period after 1994. The article shows that despite many important new developments since 1994, that there are high levels of continuity between the environmental management practices of the old and the new regimes. This state of affairs negatively impacts on the ability of the ANC government to provide every South African citizen with the clean and safe environment guaranteed to all within the 1996 Bill of Rights.This article also appeared unchanged as a chapter in the following edited collection: Jan Oosthoek and Barry K. Gills (eds), _The Globalization of Environmental Crisis_ (Abingdon: Routledge, 2008), pp. 109-120
Aegilops-Secale amphiploids: chromosome categorisation, pollen viability and identification of fungal disease resistance genes
The aim of this study was to assess the potential breeding value of goatgrass-rye amphiploids, which we are using as a “bridge” in a transfer of Aegilops chromatin (containing, e.g. leaf rust resistance genes) into triticale. We analysed the chromosomal constitution (by genomic in situ hybridisation, GISH), fertility (by pollen viability tests) and the presence of leaf rust and eyespot resistance genes (by molecular and endopeptidase assays) in a collection of 6× and 4× amphiploids originating from crosses between five Aegilops species and Secale cereale. In the five hexaploid amphiploids Aegilops kotschyi × Secale cereale (genome UUSSRR), Ae. variabilis × S. cereale (UUSSRR), Ae. biuncialis × S. cereale (UUMMRR; two lines) and Ae. ovata × S. cereale (UUMMRR), 28 Aegilops chromosomes were recognised, while in the Ae. tauschii × S. cereale amphiploid (4×; DDRR), only 14 such chromosomes were identified. In the materials, the number of rye chromosomes varied from 14 to 16. In one line of Ae. ovata × S. cereale, the U-R translocation was found. Pollen viability varied from 24.4 to 75.4%. The leaf rust resistance genes Lr22, Lr39 and Lr41 were identified in Ae. tauschii and the 4× amphiploid Ae. tauschii × S. cereale. For the first time, the leaf rust resistance gene Lr37 was found in Ae. kotschyi, Ae. ovata, Ae. biuncialis and amphiploids derived from those parental species. No eyespot resistance gene Pch1 was found in the amphiploids
Genera of Phytopathogenic Fungi: GOPHY 4
This paper is the fourth contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions and information about the pathology, distribution, hosts and disease symptoms, as well as DNA barcodes for the taxa covered. Moreover, 12 whole-genome sequences for the type or new species in the treated genera are provided. The fourth paper in the GOPHY series covers 19 genera of phytopathogenic fungi and their relatives, including Ascochyta, Cadophora, Celoporthe, Cercospora, Coleophoma, Cytospora, Dendrostoma, Didymella, Endothia, Heterophaeomoniella, Leptosphaerulina, Melampsora, Nigrospora, Pezicula, Phaeomoniella, Pseudocercospora, Pteridopassalora, Zymoseptoria, and one genus of oomycetes, Phytophthora. This study includes two new genera, 30 new species, five new combinations, and 43 typifications of older names.The study of Ascochyta, Didymella and Leptosphaerulina
were supported by the National Natural Science Foundation of China
(31750001) and the National Science and Technology Fundamental
Resources Investigation Program of China (MOST: 2021FY100900).
The study of the genus Phytophthora was supported by the Project
Phytophthora Research Centre Reg. No. CZ.02.1.01/0.0/0.0/15_003/000
0453 cofinanced by the European Regional Development Fund. ShuaiFei
Chen acknowledges the National Key R&D Program of China (ChinaSouth Africa Forestry Joint Research Centre Project; 2018YFE0120900)
for financial support. Mounes Bakhshi and Rasoul Zare gratefully
acknowledge the Iran National Science Foundation (INSF), and Research
Deputy of the Iranian Research Institute of Plant Protection, Agricultural
Research, Education and Extension Organization (AREEO), for financial
support. The study of the genera Pseudocercospora and Pteridopassalora
were partially supported by JSPS KAKENHI Grant Numbers JP20K06146
to Chiharu Nakashima
Emerging roles and competencies of district and sub-district pharmacists: a case study from Cape Town
District and sub-district pharmacist positions were created during health sector reform in South Africa.
High prevalence of HIV/AIDS, tuberculosis and increasing chronic non-communicable diseases have drawn attention to
their pivotal roles in improving accessibility and appropriate use of medicines at the primary level. This research
describes new roles and related competencies of district and sub-district pharmacists in Cape Town.
Between 2008 and 2011, the author (HB) conducted participatory action research in Cape Town Metro
District, an urban district in the Western Cape Province of South Africa, partnering with pharmacists and managers of
the two government primary health care (PHC) providers. The two providers function independently delivering
complementary PHC services across the entire geographic area, with one provider employing district pharmacists
and the other sub-district pharmacists. After an initiation phase, the research evolved into a series of iterative
cycles of action and reflection, each providing increasing understanding of district and sub-district pharmacists’
roles and competencies. Data was generated through workshops, semi-structured interviews and focus groups
with pharmacists and managers which were recorded and transcribed. Thematic analysis was carried out
iteratively during the 4-year engagement and triangulated with document reviews and published literature.
Five main roles for district and sub-district pharmacists were identified: district/sub-district management;
planning, co-ordination and monitoring of pharmaceuticals; information and advice; quality assurance and clinical
governance; and research (district pharmacists)/dispensing at clinics (sub-district pharmacists). Although the roles
looked similar, there were important differences, reflecting the differing governance and leadership models and
services of each provider. Five competency clusters were identified: professional pharmacy practice; health system
and public health; management; leadership; and personal, interpersonal and cognitive competencies. Whilst
professional pharmacy competencies were important, generic management and leadership competencies were
considered critical for pharmacists working in these positions.
Similar roles and competencies for district and sub-district pharmacists were identified in the two
PHC providers in Cape Town, although contextual factors influenced precise specifications. These insights are
important for pharmacists and managers from other districts and sub-districts in South Africa and inform health
workforce planning and capacity development initiatives in countries with similar health systems.Web of Scienc
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Overview: Second Comparative Risk Assessment for South Africa (SACRA2) highlights need for health promotion and strengthened surveillance
Background. South Africa (SA) faces multiple health challenges. Quantifying the contribution of modifiable risk factors can be used to identify and prioritise areas of concern for population health and opportunities for health promotion and disease prevention interventions.
Objective. To estimate the attributable burden of 18 modifiable risk factors for 2000, 2006 and 2012.
Methods. Comparative risk assessment (CRA), a standardised and systematic approach, was used to estimate the attributable burden of 18 risk factors. Risk exposure estimates were sourced from local data, and meta-regressions were used to model the parameters, depending on the availability of data. Risk-outcome pairs meeting the criteria for convincing or probable evidence were assessed using relative risks against a theoretical minimum risk exposure level to calculate either a potential impact fraction or population attributable fraction (PAF). Relative risks were sourced from the Global Burden of Disease, Injuries, and Risk Factors (GBD) study as well as published cohort and intervention studies. Attributable burden was calculated for each risk factor for 2000, 2006 and 2012 by applying the PAF to estimates of deaths and years of life lost from the Second South African National Burden of Disease Study (SANBD2). Uncertainty analyses were performed using Monte Carlo simulation, and age-standardised rates were calculated using the World Health Organization standard population.
Results. Unsafe sex was the leading risk factor across all years, accounting for one in four DALYs (26.6%) of the estimated 20.6 million DALYs in 2012. The top five leading risk factors for males and females remained the same between 2000 and 2012. For males, the leading risks were (in order of descending rank): unsafe sex; alcohol consumption; interpersonal violence; tobacco smoking; and high systolic blood pressure; while for females the leading risks were unsafe sex; interpersonal violence; high systolic blood pressure; high body mass index; and high fasting plasma glucose. Since 2000, the attributable age-standardised death rates decreased for most risk factors. The largest decrease was for household air pollution (–41.8%). However, there was a notable increase in the age-standardised death rate for high fasting plasma glucose (44.1%), followed by ambient air pollution (7%).
Conclusion. This study reflects the continued dominance of unsafe sex and interpersonal violence during the study period, as well as the combined effects of poverty and underdevelopment with the emergence of cardiometabolic-related risk factors and ambient air pollution as key modifiable risk factors in SA. Despite reductions in the attributable burden of many risk factors, the study reveals significant scope for health promotion and disease prevention initiatives and provides an important tool for policy makers to influence policy and programme interventions in the country
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Estimating the changing disease burden attributable to smoking in South Africa for 2000, 2006 and 2012
Background. Ongoing quantification of the disease burden attributable to smoking is important to monitor and strengthen tobacco
control policies.
Objectives. To estimate the attributable burden due to smoking in South Africa for 2000, 2006 and 2012.
Methods. We estimated attributable burden due to smoking for selected causes of death in South African (SA) adults aged ≥35 years for 2000, 2006 and 2012. We combined smoking prevalence results from 15 national surveys (1998 - 2017) and smoking impact ratios using national mortality rates. Relative risks between smoking and select causes of death were derived from local and international data.
Results. Smoking prevalence declined from 25.0% in 1998 (40.5% in males, 10.9% in females) to 19.4% in 2012 (31.9% in males, 7.9% in
females), but plateaued after 2010. In 2012 tobacco smoking caused an estimated 31 078 deaths (23 444 in males and 7 634 in females),
accounting for 6.9% of total deaths of all ages (17.3% of deaths in adults aged ≥35 years), a 10.5% decline overall since 2000 (7% in males; 18% in females). Age-standardised mortality rates (and disability-adjusted life years (DALYs)) similarly declined in all population groups but remained high in the coloured population. Chronic obstructive pulmonary disease accounted for most tobacco-attributed deaths (6 373), followed by lung cancer (4 923), ischaemic heart disease (4 216), tuberculosis (2 326) and lower respiratory infections (1 950). The distribution of major causes of smoking-attributable deaths shows a middle- to high-income pattern in whites and Asians, and a middle- to low-income pattern in coloureds and black Africans. The role of infectious lung disease (TB and LRIs) has been underappreciated. These diseases comprised 21.0% of deaths among black Africans compared with only 4.3% among whites. It is concerning that smoking rates have plateaued since 2010.
Conclusion. The gains achieved in reducing smoking prevalence in SA have been eroded since 2010. An increase in excise taxes is the most effective measure for reducing smoking prevalence. The advent of serious respiratory pandemics such as COVID-19 has increased the urgency of considering the role that smoking cessation/abstinence can play in the prevention of, and post-hospital recovery from, any condition
Prevalence, Causes and Socio-Economic Determinants of Vision Loss in Cape Town, South Africa
PURPOSE: To estimate the prevalence and causes of blindness and visual impairment in Cape Town, South Africa and to explore socio-economic and demographic predictors of vision loss in this setting. METHODS: A cross sectional population-based survey was conducted in Cape Town. Eighty-two clusters were selected using probability proportionate to size sampling. Within each cluster 35 or 40 people aged 50 years and above were selected using compact segment sampling. Visual acuity of participants was assessed and eyes with a visual acuity less than 6/18 were examined by an ophthalmologist to determine the cause of vision loss. Demographic data (age, gender and education) were collected and a socio-economic status (SES) index was created using principal components analysis. RESULTS: Out of 3100 eligible people, 2750 (89%) were examined. The sample prevalence of bilateral blindness (presenting visual acuity <3/60) was 1.4% (95% CI 0.9-1.8). Posterior segment diseases accounted for 65% of blindness and cataract was responsible for 27%. The prevalence of vision loss was highest among people over 80 years (odds ratio (OR) 6.9 95% CI 4.6-10.6), those in the poorest SES group (OR 3.9 95% CI 2.2-6.7) and people with no formal education (OR 5.4 95% CI 1.7-16.6). Cataract surgical coverage was 68% in the poorest SES tertile (68%) compared to 93% in the medium and 100% in the highest tertile. CONCLUSIONS: The prevalence of blindness among people ≥50 years in Cape Town was lower than expected and the contribution of posterior segment diseases higher than previously reported in South Africa and Sub Saharan Africa. There were clear socio-economic disparities in prevalence of vision loss and cataract surgical coverage in this setting which need to be addressed in blindness prevention programs
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