Computer-aided: Modelled sustainable hybrid catalysts for a nano-drug delivery system

We evaluated a hybrid catalytic power source for less invasive internal electroporation with better tissue reach than the widely used and more invasive external electroporation.We modelled how open-circuit voltage optimizes platinum-loading in catalysts to improve the electrochemical activity (ECA) possible from bioelectrogenesis through these systems and address the high costs of nano-drug delivery systems. The effects of the catalysts’ convective flux and proton concentration were modelled for an enzyme (glucose oxidase) biofuel cell that was fed glucose substrate at a current rate under isothermal physiological conditions. Glucose concentrations were varied relative to anode catalyst loading models with 0.1–0.5 mg cm–2 platinum and alloyed (Pt-Ru-Ni) with a narrowparticle size distribution. Using the free (solvation) electron model, bioelectrochemical activity (BECA) and a high open circuit voltage were generated by 5.5, 10 and 20mMglucose with 20kUL–1 glucose oxidase at 37 °C.BECA(glucose oxidase), on its own, produced pulses of various intensities for nano–microsecond durations whereas the hybrid BECA-ECA (glucose oxidase and platinum) anode catalyst provided sustainable pulses of microseconds–minute durations. Enhanced catalysis with the hybrid BECA-ECA’s open circuit voltage favours compatibility of a hybrid-powered nano-drug delivery system for internal electroporation

Evidence of pervasive biologically functional secondary-structures within the genomes of eukaryotic single-stranded DNA viruses

Single-stranded DNA (ssDNA) viruses have genomes that are potentially capable of forming complex secondary-structures through Watson-Crick base-pairing between their constituent nucleotides. A few of the structural elements formed by such base-pairings are, in fact, known to have important functions during the replication of many ssDNA viruses. What is unknown, however, is (i) whether numerous additional ssDNA virus genomic structural elements predicted to exist by computational DNA folding methods actually exist, and (ii) whether those structures that do exist have any biological relevance. We therefore computationally inferred lists of the most evolutionarily conserved structures within a diverse selection of animal- and plant-infecting ssDNA viruses drawn from the families Circoviridae, Anelloviridae, Parvoviridae, Nanoviridae andGeminiviridae, and analysed these for evidence of natural selection favouring the maintenance of these structures. While we find evidence that is consistent with purifying selection being stronger at nucleotide sites that are predicted to be base-paired than it is at sites predicted to be unpaired, we also find strong associations between sites that are predicted to pair with one another and site pairs that are apparently coevolving in a complementary fashion. Collectively, these results indicate that natural selection actively preserves much of the pervasive secondary-structure that is evident within eukaryote-infecting ssDNA virus genomes and, therefore, that much of this structure is biologically functional. Lastly, we provide examples of various highly conserved but completely uncharacterised structural elements that likely have important functions within some of the ssDNA virus genomes analysed here

Evidence of pervasive biologically functional secondary structures within the Genomes of Eukaryotic Single-Stranded DNA Viruses

Single-stranded DNA (ssDNA) viruses have genomes that are potentially capable of forming complex secondary structures through Watson-Crick base pairing between their constituent nucleotides. A few of the structural elements formed by such base pairings are, in fact, known to have important functions during the replication of many ssDNA viruses. Unknown, however, are (i) whether numerous additional ssDNA virus genomic structural elements predicted to exist by computational DNA folding methods actually exist and (ii) whether those structures that do exist have any biological relevance. We therefore computationally inferred lists of the most evolutionarily conserved structures within a diverse selection of animal- and plant-infecting ssDNA viruses drawn from the families Circoviridae, Anelloviridae, Parvoviridae, Nanoviridae, and Geminiviridae and analyzed these for evidence of natural selection favoring the maintenance of these structures. While we find evidence that is consistent with purifying selection being stronger at nucleotide sites that are predicted to be base paired than at sites predicted to be unpaired, we also find strong associations between sites that are predicted to pair with one another and site pairs that are apparently coevolving in a complementary fashion. Collectively, these results indicate that natural selection actively preserves much of the pervasive secondary structure that is evident within eukaryote-infecting ssDNA virus genomes and, therefore, that much of this structure is biologically functional. Lastly, we provide examples of various highly conserved but completely uncharacterized structural elements that likely have important functions within some of the ssDNA virus genomes analyzed here.Department of HE and Training approved lis

Evidence of pervasive biologically functional secondary-structures within the genomes of eukaryotic single-stranded DNA viruses

Single-stranded DNA (ssDNA) viruses have genomes that are potentially capable of forming complex secondary structures through Watson-Crick base pairing between their constituent nucleotides. A few of the structural elements formed by such base pairings are, in fact, known to have important functions during the replication of many ssDNA viruses. Unknown, however, are (i) whether numerous additional ssDNA virus genomic structural elements predicted to exist by computational DNA folding methods actually exist and (ii) whether those structures that do exist have any biological relevance. We therefore computationally inferred lists of the most evolutionarily conserved structures within a diverse selection of animal- and plant-infecting ssDNA viruses drawn from the families Circoviridae, Anelloviridae, Parvoviridae, Nanoviridae, and Geminiviridae and analyzed these for evidence of natural selection favoring the maintenance of these structures. While we find evidence that is consistent with purifying selection being stronger at nucleotide sites that are predicted to be base paired than at sites predicted to be unpaired, we also find strong associations between sites that are predicted to pair with one another and site pairs that are apparently coevolving in a complementary fashion. Collectively, these results indicate that natural selection actively preserves much of the pervasive secondary structure that is evident within eukaryote-infecting ssDNA virus genomes and, therefore, that much of this structure is biologically functional. Lastly, we provide examples of various highly conserved but completely uncharacterized structural elements that likely have important functions within some of the ssDNA virus genomes analyzed here

Investigating the resurgence of malaria prevalence in South Africa between 2015 and 2018 : a scoping review

BACKGROUND : Malaria remains a serious concern in most African countries, causing nearly one million deaths globally every year. This review aims to examine the extent and nature of the resurgence of malaria transmission in South Africa. METHODS : Using the Arksey and O'Malley framework, this scoping review includes articles published between the years 2015 and 2018 on the resurgence of malaria occurrence in South Africa. Articles were searched between October 2018 to January 2019 using the following electronic databases: CINAHL, Pubmed, Science Direct and SCOPUS. Grey literature from Google Scholar was also hand searched. Key search terms and subject headings such as climate variables, climate changes, climatic factors, malaria resurgence, malaria reoccurrence and malaria increase over epidemic regions in South Africa were used to identify relevant articles. Three independent reviewers performed the selection and characterization of articles, and the data collected were synthesized qualitatively. RESULTS : A total number of 534 studies were identified. Among these, 24 studies met the inclusion criteria. The results were grouped by factors (four main themes) that influenced the malaria resurgence: Climatic, Epidemiological, Socio-economic, and Environmental factors. Climatic factors were found to be the major factor responsible for the resurgence of malaria, as more than 55% of the selected articles were climate-focused. This was followed by epidemiological, socio-economic and environmental factors, in that order. Grey literature from Google Scholar yielded no results. CONCLUSION : This study shows that malaria transmission in South Africa is more associated with climate. Climate-based malaria models could be used as early warning systems for malaria over the epidemic regions in South Africa. Since epidemiological factors also play significant roles in malaria transmission, regular and unrelaxed use of Indoor Residual Spraying (IRS) should be encouraged in these regions. Individuals should also be educated on the importance and the usefulness of these deliveries. While some studies have indicated that the vectors have developed resistance to insecticides, continuous research on developing new insecticides that could alter the resistance are encouraged. Furthermore, all efforts to eradicate malaria in South Africa must also target malaria-endemic neighbouring countries.The University of Pretoria Institute for Sustainable Malaria Control (UP ISMC) and Malaria Research Control (MRC)https://benthamopen.com/TOPHJ/home/am2021School of Health Systems and Public Health (SHSPH