78 research outputs found

    Taxing the Minerals Sector in South Africa: a comparative analysis of the proposed tax model for South Africa and the models adopted in selected African countries

    Get PDF
    The State Intervention in the Minerals Sector Report emerged as a resolution during the 3rd National General Council Resolution on Economic Transformation held in 2012, during which the Council stated that: “The ANC’s approach to economic transformation of the South African economy should always be holistic and comprehensive, covering all sectors of the economy. In this regard, the ANC should ensure greater state involvement and control of strategic sectors of the economy, such as mining, energy, the financial sector and others.” It was for this reason that the National General Council mandated the National Executive Committee to ensure that further work be done on ways in which the African National Congress can implement economic transformation in sectors such as the mining industry. It was suggested that methods including research, study tours and discussions be conducted to gather the required information. As a result of the research, The State Intervention in the Minerals Sector Report emerged. In The State Intervention in the Minerals Sector Report, the mineral sectors of developed as well as developing countries are compared with each other. The developing countries compared included Botswana, Zambia, Ghana, Liberia and Sierra Leone, and these countries have also been selected for the purpose of comparison in the present research. The goal of this study is to analyse the recommendations made in The State Intervention in the Minerals Sector Report regarding State involvement in the minerals sector. To determine whether the economic situation in South Africa is comparable to the five other African countries, an analysis based on demographic indicators, the history of the minerals sector in the various countries, its contribution to the fiscal regime of that country, its economic contribution, as well as the extent of involvement from Government and the model implemented for its involvement, is conducted. According to a work paper published by the World Bank on the world development indicators for 2014, control over metal supply to the economy has been considered vital for political and economic reasons in most societies. It further states that most State-owned mining companies have over the years and, in particular, in developing countries, not been able to operate successfully, leading to privatisation. Poor performance is, however, not necessarily the reason for State ownership. Areas not addressed by this thesis include the Gold Mining industry in South Africa and the Diamond mining industry in Botswana

    Design and Synthesis of Visible-Light-Responsive Azobenzene Building Blocks for Chemical Biology

    Get PDF
    Tetra-ortho-fluoro-azobenzenes are a class of photoswitches useful for the construction of visible-light-controlled molecular systems. They can be used to achieve spatio-temporal control over the properties of a chosen bioactive molecule. However, the introduction of different substituents to the tetra-fluoro-azobenzene core can significantly affect the photochemical properties of the switch and compromise biocompatibility. Herein, we explored the effect of useful substituents, such as functionalization points, attachment handles, and water-solubilizing groups, on the photochemical properties of this photochromic system. In general, all the tested fluorinated azobenzenes exhibited favorable photochemical properties, such as high photostationary state distribution and long half-lives, both in organic solvents and in water. One of the azobenzene building blocks was functionalized with a trehalose group to enable the uptake of the photoswitch into mycobacteria. Following metabolic uptake and incorporation of the trehalose-based azobenzene in the mycobacterial cell wall, we demonstrated photoswitching of the azobenzene in the isolated total lipid extract

    Von Willebrand factor and the thrombophilia of severe COVID-19: in situ evidence from autopsies

    Get PDF
    BACKGROUND: COVID-19 is accompanied by a hypercoagulable state and characterized by microvascular and macrovascular thrombotic complications. In plasma samples from patients with COVID-19, von Willebrand factor (VWF) levels are highly elevated and predictive of adverse outcomes, especially mortality. Yet, VWF is usually not included in routine coagulation analyses, and histologic evidence of its involvement in thrombus formation is lacking. OBJECTIVES: To determine whether VWF, an acute-phase protein, is a bystander, ie, a biomarker of endothelial dysfunction, or a causal factor in the pathogenesis of COVID-19. METHODS: We compared autopsy samples from 28 patients with lethal COVID-19 to those from matched controls and systematically assessed for VWF and platelets by immunohistochemistry. The control group comprised 24 lungs, 23 lymph nodes, and 9 hearts and did not differ significantly from the COVID-19 group in age, sex, body mass index (BMI), blood group, or anticoagulant use. RESULTS: In lungs, assessed for platelets by immunohistochemistry for CD42b, microthrombi were more frequent in patients with COVID-19 (10/28 [36%] vs 2/24 [8%]; P = .02). A completely normal pattern of VWF was rare in both groups. Accentuated endothelial staining was found in controls, while VWF-rich thrombi were only found in patients with COVID-19 (11/28 [39%] vs 0/24 [0%], respectively; P < .01), as were NETosis thrombi enriched with VWF (7/28 [25%] vs 0/24 [0%], respectively; P < .01). Forty-six percent of the patients with COVID-19 had VWF-rich thrombi, NETosis thrombi, or both. Trends were also seen in pulmonary draining lymph nodes (7/20 [35%] vs 4/24 [17%]; P = .147), where the overall presence of VWF was very high. CONCLUSION: We provide in situ evidence of VWF-rich thrombi, likely attributable to COVID-19, and suggest that VWF may be a therapeutic target in severe COVID-19

    New Molecular Reporters for Rapid Protein Folding Assays

    Get PDF
    The GFP folding reporter assay [1] uses a C-terminal GFP fusion to report on the folding success of upstream fused polypeptides. The GFP folding assay is widely-used for screening protein variants with improved folding and solubility [2]–[8], but truncation artifacts may arise during evolution, i.e. from de novo internal ribosome entry sites [9]. One way to reduce such artifacts would be to insert target genes within the scaffolding of GFP circular permuted variants. Circular permutants of fluorescent proteins often misfold and are non-fluorescent, and do not readily tolerate fused polypeptides within the fluorescent protein scaffolding [10]–[12]. To overcome these limitations, and to increase the dynamic range for reporting on protein misfolding, we have created eight GFP insertion reporters with different sensitivities to protein misfolding using chimeras of two previously described GFP variants, the GFP folding reporter [1] and the robustly-folding “superfolder” GFP [13]. We applied this technology to engineer soluble variants of Rv0113, a protein from Mycobacterium tuberculosis initially expressed as inclusion bodies in Escherichia coli. Using GFP insertion reporters with increasing stringency for each cycle of mutagenesis and selection led to a variant that produced large amounts of soluble protein at 37°C in Escherichia coli. The new reporter constructs discriminate against truncation artifacts previously isolated during directed evolution of Rv0113 using the original C-terminal GFP folding reporter. Using GFP insertion reporters with variable stringency should prove useful for engineering protein variants with improved folding and solubility, while reducing the number of artifacts arising from internal cryptic ribosome initiation sites

    Gold nanoparticle conjugated Rad6 inhibitor induces cell death in triple negative breast cancer cells by inducing mitochondrial dysfunction and PARP-1 hyperactivation: Synthesis and characterization

    Get PDF
    We recently developed a small molecule inhibitor SMI#9 for Rad6, a protein overexpressed in aggressive breast cancers and involved in DNA damage tolerance. SMI#9 induces cytotoxicity in cancerous cells but spares normal breast cells; however, its therapeutic efficacy is limited by poor solubility. Here we chemically modified SMI#9 to enable its conjugation and hydrolysis from gold nanoparticle (GNP). SMI#9-GNP and parent SMI#9 activities were compared in mesenchymal and basal triple negative breast cancer (TNBC) subtype cells. Whereas SMI#9 is cytotoxic to all TNBC cells, SMI#9-GNP is endocytosed and cytotoxic only in mesenchymal TNBC cells. SMI#9-GNP endocytosis in basal TNBCs is compromised by aggregation. However, when combined with cisplatin, SMI#9-GNP is imported and synergistically increases cisplatin sensitivity. Like SMI#9, SMI#9-GNP spares normal breast cells. The released SMI#9 is active and induces cell death via mitochondrial dysfunction and PARP-1 stabilization/hyperactivation. This work signifies the development of a nanotechnology-based Rad6-targeting therapy for TNBCs

    Neuropsychiatric risk in children with intellectual disability of genetic origin: IMAGINE - The UK National Cohort Study

    Get PDF
    Background: Children with intellectual disability (ID) frequently have multiple co-morbid neuropsychiatric conditions and poor physical health. Genomic testing is increasingly recommended as a first-line investigation for these children. We aimed to determine the impact of genomics, inheritance and socioeconomic deprivation on neuropsychiatric risk in children with intellectual disability of genetic origin as compared to the general population. Methods: IMAGINE is a prospective study using online mental health and medical assessments in a cohort of 2770 children with ID and pathogenic genomic variants, identified by the UK’s National Health Service. Outcomes: Assessments completed on 2397 young people with ID (4-19 years, M 9·2, SD 3·9) with a rare pathogenic genomic variant. 1339 (55·9%) were male. 1771 (73·9%) of participants had a pathogenic copy number variant (CNV), 626 (26·1%) a pathogenic single nucleotide variant (SNV). Participants were representative of the socioeconomic spectrum of the UK general population. The relative risk of co-occurring neuropsychiatric diagnoses, compared with the UK national population, was high: Autism Spectrum Disorder 29·2 (95% CI 23·9 to 36·5), Attention Deficit Hyperactivity Disorder 13·5 (95% CI 11·1 to 16·3). In children with a CNV, those with a familial variant tended to live in more socioeconomically deprived areas. Both inheritance and socioeconomic deprivation contributed to neuropsychiatric risk in those with a CNV. Interpretation: Children with genomic variants and ID are at a greatly enhanced risk of neuropsychiatric difficulties. CNV variant inheritance and socioeconomic deprivation also contribute to the risk

    Association of maternal prenatal smoking GFI1-locus and cardiometabolic phenotypes in 18,212 adults

    Get PDF
    Background: DNA methylation at the GFI1-locus has been repeatedly associated with exposure to smoking from the foetal period onwards. We explored whether DNA methylation may be a mechanism that links exposure to maternal prenatal smoking with offspring's adult cardio-metabolic health. Methods: We meta-analysed the association between DNA methylation at GFI1-locus with maternal prenatal smoking, adult own smoking, and cardio-metabolic phenotypes in 22 population-based studies from Europe, Australia, and USA (n= 18,212). DNA methylation at the GFI1-locus was measured in whole-blood. Multivariable regression models were fitted to examine its association with exposure to prenatal and own adult smoking. DNA methylation levels were analysed in relation to body mass index (BMI), waist circumference (WC), fasting glucose (FG), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), diastolic, and systolic blood pressure (BP). Findings: Lower DNA methylation at three out of eight GFI1-CpGs was associated with exposure to maternal prenatal smoking, whereas, all eight CpGs were associated with adult own smoking. Lower DNA methylation at cg14179389, the strongest maternal prenatal smoking locus, was associated with increased WC and BP when adjusted for sex, age, and adult smoking with Bonferroni-corrected P &lt; 0.012. In contrast, lower DNA methylation at cg09935388, the strongest adult own smoking locus, was associated with decreased BMI, WC, and BP (adjusted 1 x 10(-7) &lt; P &lt; 0.01). Similarly, lower DNA methylation at cg12876356, cg18316974, cg09662411, and cg18146737 was associated with decreased BMI and WC (5 x 10(-8) &lt; P &lt; 0.001). Lower DNA methylation at all the CpGs was consistently associated with higher TG levels. Interpretation: Epigenetic changes at the GFI1 were linked to smoking exposure in-utero/in-adulthood and robustly associated with cardio-metabolic risk factors. Fund: European Union's Horizon 2020 research and innovation programme under grant agreement no. 633595 DynaHEALTH

    Neuropsychiatric risk in children with intellectual disability of genetic origin: IMAGINE, a UK national cohort study

    Get PDF
    Background Children with intellectual disability frequently have multiple co-morbid neuropsychiatric conditions and poor physical health. Genomic testing is increasingly recommended as a first-line investigation for these children. We aim to determine the effect of genomics, inheritance, and socioeconomic deprivation on neuropsychiatric risk in children with intellectual disability of genetic origin as compared with the general population. Methods IMAGINE is a prospective cohort study using online mental health and medical assessments in a cohort of 3407 UK participants with intellectual disability and pathogenic genomic variants as identified by the UK's National Health Service (NHS). Our study is on a subset of these participants, including all children aged 4–19 years. We collected diagnostic genomic reports from NHS records and asked primary caregivers to provide an assessment of their child using the Development and Well-Being Assessment (DAWBA), the Strengths and Difficulties Questionnaire (SDQ), the Adaptive Behaviour Assessment System 3 (ABAS-3), and a medical history questionnaire. Each child was assigned a rank based on their postcode using the index of multiple deprivation (IMD). We compared the IMAGINE cohort with the 2017 National Survey of Children's Mental Health in England. The main outcomes of interest were mental health and neurodevelopment according to the DAWBA and SDQ. Findings We recruited 2770 children from the IMAGINE study between Oct 1, 2014 and June 30, 2019, of whom 2397 (86·5%) had a basic assessment of their mental health completed by their families and 1277 (46·1%) completed a medical history questionnaire. The mean age of participants was 9·2 years (SD 3·9); 1339 (55·9%) were boys and 1058 (44·1%) were girls. 355 (27·8%) of 1277 reported a seizure disorder and 814 (63·7%) reported movement or co-ordination problems. 1771 (73·9%) of 2397 participants had a pathogenic copy number variant (CNV) and 626 (26·1%) had a pathogenic single nucleotide variant (SNV). Participants were representative of the socioeconomic spectrum of the UK general population. The relative risk (RR) of co-occurring neuropsychiatric diagnoses, compared with the English national population, was high: autism spectrum disorder RR 29·2 (95% CI 23·9–36·5), ADHD RR 13·5 (95% CI 11·1–16·3). In children with a CNV, those with a familial variant tended to live in more socioeconomically deprived areas than those with a de novo variant. Both inheritance and socioeconomic deprivation contributed to neuropsychiatric risk in those with a CNV. Interpretation Children with genomic variants and intellectual disability are at an increased risk of neuropsychiatric difficulties. CNV variant inheritance and socioeconomic deprivation also contribute to the risk. Early genomic investigations of children with intellectual disability could facilitate the identification of the most vulnerable children. Additionally, harnessing parental expertise using online DAWBA assessments could rapidly identify children with exceptional needs to child mental health services

    Genetic correlation between amyotrophic lateral sclerosis and schizophrenia

    Get PDF
    A. Palotie on työryhmÀn Schizophrenia Working Grp Psychiat jÀsen.We have previously shown higher-than-expected rates of schizophrenia in relatives of patients with amyotrophic lateral sclerosis (ALS), suggesting an aetiological relationship between the diseases. Here, we investigate the genetic relationship between ALS and schizophrenia using genome-wide association study data from over 100,000 unique individuals. Using linkage disequilibrium score regression, we estimate the genetic correlation between ALS and schizophrenia to be 14.3% (7.05-21.6; P = 1 x 10(-4)) with schizophrenia polygenic risk scores explaining up to 0.12% of the variance in ALS (P = 8.4 x 10(-7)). A modest increase in comorbidity of ALS and schizophrenia is expected given these findings (odds ratio 1.08-1.26) but this would require very large studies to observe epidemiologically. We identify five potential novel ALS-associated loci using conditional false discovery rate analysis. It is likely that shared neurobiological mechanisms between these two disorders will engender novel hypotheses in future preclinical and clinical studies.Peer reviewe
    • 

    corecore