312 research outputs found
Can mining promote industrialization? A comparative analysis of policy frameworks in three Southern African countries
This paper explores the potential to leverage large-scale mineral extraction in Botswana, Zambia, and Zimbabwe to foster mineral beneficiation and upstream industries. The evidence suggests that the success or failure of a resource-based industrialization approach is country and sector specific, requiring the deployment of different and appropriately tailored policy instruments. We also find that the design and implementation of resource-based industrialization policies is heavily influenced by power relationships, in terms of control over mining rents, relationships between mining companies and domestic business, and across different segments of the domestic business sector
Mining-related national systems of innovation in southern Africa: National trajectories and regional integration
This paper explores the linkages between the national systems of innovation of Botswana, South Africa, Zambia, and Zimbabwe and their respective mineral extraction and mineral processing value chains, including input industries. Our analysis reveals four individual national systems of innovation, with different outcomes in terms of engineering skills development, technical vocational education and training, research and development, innovation capabilities, and competitiveness of the domestic engineering consultancy services. These national systems of innovation are tentatively interconnected as an embryonic regional system of innovation, including institutional relationships, cross-border investment flows, flows of mining-related goods and services, and intra-Southern African Development Community flows of students, lecturers, technicians, and engineers. Notwithstanding important dynamics related to skills development and competence building happening across borders, more collaborative and synergistic initiatives between government, industry, and teaching and research institutions are required to shape a more balanced and coherent regional systems of innovation
A four-month gatifloxacin-containing regimen for treating tuberculosis.
BACKGROUND: Shortening the course of treatment for tuberculosis would be a major improvement for case management and disease control. This phase 3 trial assessed the efficacy and safety of a 4-month gatifloxacin-containing regimen for treating rifampin-sensitive pulmonary tuberculosis. METHODS: We conducted a noninferiority, randomized, open-label, controlled trial involving patients 18 to 65 years of age with smear-positive, rifampin-sensitive, newly diagnosed pulmonary tuberculosis in five sub-Saharan African countries. A standard 6-month regimen that included ethambutol during the 2-month intensive phase was compared with a 4-month regimen in which gatifloxacin (400 mg per day) was substituted for ethambutol during the intensive phase and was continued, along with rifampin and isoniazid, during the continuation phase. The primary efficacy end point was an unfavorable outcome (treatment failure, recurrence, or death or study dropout during treatment) measured 24 months after the end of treatment, with a noninferiority margin of 6 percentage points, adjusted for country. RESULTS: A total of 1836 patients were assigned to the 4-month regimen (experimental group) or the standard regimen (control group). Baseline characteristics were well balanced between the groups. At 24 months after the end of treatment, the adjusted difference in the risk of an unfavorable outcome (experimental group [21.0%] minus control group [17.2%]) in the modified intention-to-treat population (1356 patients) was 3.5 percentage points (95% confidence interval, -0.7 to 7.7). There was heterogeneity across countries (P=0.02 for interaction, with differences in the rate of an unfavorable outcome ranging from -5.4 percentage points in Guinea to 12.3 percentage points in Senegal) and in baseline cavitary status (P=0.04 for interaction) and body-mass index (P=0.10 for interaction). The standard regimen, as compared with the 4-month regimen, was associated with a higher dropout rate during treatment (5.0% vs. 2.7%) and more treatment failures (2.4% vs. 1.7%) but fewer recurrences (7.1% vs. 14.6%). There was no evidence of increased risks of prolongation of the QT interval or dysglycemia with the 4-month regimen. CONCLUSIONS: Noninferiority of the 4-month regimen to the standard regimen with respect to the primary efficacy end point was not shown. (Funded by the Special Program for Research and Training in Tropical Diseases and others; ClinicalTrials.gov number, NCT00216385.)
High Rates of Potentially Infectious Tuberculosis and Multidrug-Resistant Tuberculosis (MDR-TB) among Hospital Inpatients in KwaZulu Natal, South Africa Indicate Risk of Nosocomial Transmission
Background: Nosocomial transmission has been implicated as a key factor in the outbreak of extensively drug resistant (XDR) and multidrug-resistant (MDR-TB) tuberculosis at Church of Scotland Hospital (CoSH), in KwaZulu-Natal (KZN), South Africa. The aim of this study was to quantify the burden of potentially infectious tuberculosis and the proportion of drug resistance among hospital inpatients throughout the province of KZN. Methods: Inpatients with current cough, capable of producing sputum were selected from 19 public hospitals in KZN. After informed consent, demographic and clinical data, and sputum samples were collected. Samples were processed for fluorescent microscopy, liquid culture and first and second-line anti-tuberculosis drug susceptibility testing. Results: There were a total of 2,964 inpatients where sampling was done. About 1,585 inpatients (53%) had a current cough and sufficient microbiological and clinical data for inclusion. Mycobacterium tuberculosis was isolated from 543 inpatients (34% of those tested and 18% of all inpatients). Eighty-four (15%) inpatients with TB were found to be MDR-TB infected and 16 (3%) had XDR-TB. There was no association between the prevalence of MDR-TB and proximity to CoSH. Among patients with microbiologically confirmed TB, MDR/XDR-TB was associated with male sex, a longer length of stay between hospital admission and date of sample collection, and current or previous TB treatment. Conclusions: One in five inpatients had potentially infectious TB. This is an underestimate since patients without current cough were not tested. MDR-TB was frequently observed and was found in nearly one in six active TB inpatients. While present at lower levels than the original outbreak report at CoSH, XDR-TB was detected in hospitals throughout KZN. The high burden of potentially infectious TB and confirmed MDR-TB, much of it undiagnosed, indicates a serious risk for nosocomial transmission and the need for intensified infection control within the inpatient setting
Resource-based industrialisation in Southern Africa: Domestic policies, corporate strategies and regional dynamics
Abstract: This article analyses policies and strategies adopted by Botswana, Zambia and Zimbabwe in order to develop linkage industries from the mineral sector. Whilst Southern Africa has a strongly integrated regional value chain for equipment and services related to mining, linkage development strategies in the three countries under examination have been formulated within narrow domestic frameworks. The evidence suggests that the success or failure of a resource-based industrialisation approach is country and sector specific, requiring the deployment of different and appropriately tailored policy instruments. Our research uncovered important cross-country variations in terms of opportunities created by specific mineral commodities, ambition and scope of industrial and linkage development strategies, and institutional capabilities to ensure enforcement and coherence with other policies
Drivers of Tuberculosis Transmission.
Measuring tuberculosis transmission is exceedingly difficult, given the remarkable variability in the timing of clinical disease after Mycobacterium tuberculosis infection; incident disease can result from either a recent (ie, weeks to months) or a remote (ie, several years to decades) infection event. Although we cannot identify with certainty the timing and location of tuberculosis transmission for individuals, approaches for estimating the individual probability of recent transmission and for estimating the fraction of tuberculosis cases due to recent transmission in populations have been developed. Data used to estimate the probable burden of recent transmission include tuberculosis case notifications in young children and trends in tuberculin skin test and interferon γ-release assays. More recently, M. tuberculosis whole-genome sequencing has been used to estimate population levels of recent transmission, identify the distribution of specific strains within communities, and decipher chains of transmission among culture-positive tuberculosis cases. The factors that drive the transmission of tuberculosis in communities depend on the burden of prevalent tuberculosis; the ways in which individuals live, work, and interact (eg, congregate settings); and the capacity of healthcare and public health systems to identify and effectively treat individuals with infectious forms of tuberculosis. Here we provide an overview of these factors, describe tools for measurement of ongoing transmission, and highlight knowledge gaps that must be addressed
Underreporting and overreporting of hepatitis B at a tertiary hospital
Objective. To assess the level of underreporting and overreporting of hepatitis B infection at a tertiary hospital.Design. Retrospective record review.Setting. King Edward VIII Hospital, Durban.Main outcome measures. Hepatitis B notification was assessed. Underreporting was ascertained on the basis of the proportion of hepatitis B-positive laboratory results that were not notified. Overreporting was indicated by duplication of notifications and the reporting of patients who have not tested positive for hepatitis B.Results. 83.7% (95% confidence interval 79.4 - 88.0%) of patients with hepatitis B virus infection were not reported. no hospital outpatients were reported and 6% (95% confidence interval 0 - 12.6%) of the reported hepatitis B cases were not hepatitis B.Conclusion. Underreporting of hepatitis B virus infection is the result of an inadequate notification system at a health institution level. A new, user-friendly system of surveillance that actively monitors the reporting rate is recommended to improve the reporting rate and thus generates useful information
Water dispersible microbicidal cellulose acetate phthalate film
BACKGROUND: Cellulose acetate phthalate (CAP) has been used for several decades in the pharmaceutical industry for enteric film coating of oral tablets and capsules. Micronized CAP, available commercially as "Aquateric" and containing additional ingredients required for micronization, used for tablet coating from water dispersions, was shown to adsorb and inactivate the human immunodeficiency virus (HIV-1), herpesviruses (HSV) and other sexually transmitted disease (STD) pathogens. Earlier studies indicate that a gel formulation of micronized CAP has a potential as a topical microbicide for prevention of STDs including the acquired immunodeficiency syndrome (AIDS). The objective of endeavors described here was to develop a water dispersible CAP film amenable to inexpensive industrial mass production. METHODS: CAP and hydroxypropyl cellulose (HPC) were dissolved in different organic solvent mixtures, poured into dishes, and the solvents evaporated. Graded quantities of a resulting selected film were mixed for 5 min at 37°C with HIV-1, HSV and other STD pathogens, respectively. Residual infectivity of the treated viruses and bacteria was determined. RESULTS: The prerequisites for producing CAP films which are soft, flexible and dispersible in water, resulting in smooth gels, are combining CAP with HPC (other cellulose derivatives are unsuitable), and casting from organic solvent mixtures containing ≈50 to ≈65% ethanol (EtOH). The films are ≈100 µ thick and have a textured surface with alternating protrusions and depressions revealed by scanning electron microscopy. The films, before complete conversion into a gel, rapidly inactivated HIV-1 and HSV and reduced the infectivity of non-viral STD pathogens >1,000-fold. CONCLUSIONS: Soft pliable CAP-HPC composite films can be generated by casting from organic solvent mixtures containing EtOH. The films rapidly reduce the infectivity of several STD pathogens, including HIV-1. They are converted into gels and thus do not have to be removed following application and use. In addition to their potential as topical microbicides, the films have promise for mucosal delivery of pharmaceuticals other than CAP
Systematic review of allelic exchange experiments aimed at identifying mutations that confer drug resistance in Mycobacterium tuberculosis
First published online: September 20, 2013BACKGROUND:
Improving our understanding of the relationship between the genotype and the drug resistance phenotype of Mycobacterium tuberculosis will aid the development of more accurate molecular diagnostics for drug-resistant tuberculosis. Studies that use direct genetic manipulation to identify the mutations that cause M. tuberculosis drug resistance are superior to associational studies in elucidating an individual mutation's contribution to the drug resistance phenotype.
METHODS:
We systematically reviewed the literature for publications reporting allelic exchange experiments in any of the resistance-associated M. tuberculosis genes. We included studies that introduced single point mutations using specialized linkage transduction or site-directed/in vitro mutagenesis and documented a change in the resistance phenotype.
RESULTS:
We summarize evidence supporting the causal relationship of 54 different mutations in eight genes (katG, inhA, kasA, embB, embC, rpoB, gyrA and gyrB) and one intergenic region (furA-katG) with resistance to isoniazid, the rifamycins, ethambutol and fluoroquinolones. We observed a significant role for the strain genomic background in modulating the resistance phenotype of 21 of these mutations and found examples of where the same drug resistance mutations caused varying levels of resistance to different members of the same drug class.
CONCLUSIONS:
This systematic review highlights those mutations that have been shown to causally change phenotypic resistance in M. tuberculosis and brings attention to a notable lack of allelic exchange data for several of the genes known to be associated with drug resistance.This work was supported by the Portuguese Foundation for Science and Technology (FCT) (SFRH/BD/33902/2009 to H. N.-G.), the National Institutes of Health/Fogarty International Center (1K01 TW009213 to K.R.J.), departmental funds of the pulmonary division of Massachusetts General Hospital to M. R. F. and the National Institutes of Health/NIAID (U19 A1076217 to M.B.M.)
Analysis of vaginal microbicide film hydration kinetics by quantitative imaging refractometry
We have developed a quantitative imaging refractometry technique, based on holographic phase microscopy, as a tool for investigating microscopic structural changes in water-soluble polymeric materials. Here we apply the approach to analyze the structural degradation of vaginal topical microbicide films due to water uptake. We implemented transmission imaging of 1-mm diameter film samples loaded into a flow chamber with a 1.5×2 mm field of view. After water was flooded into the chamber, interference images were captured and analyzed to obtain high resolution maps of the local refractive index and subsequently the volume fraction and mass density of film material at each spatial location. Here, we compare the hydration dynamics of a panel of films with varying thicknesses and polymer compositions, demonstrating that quantitative imaging refractometry can be an effective tool for evaluating and characterizing the performance of candidate microbicide film designs for anti-HIV drug delivery. © 2014 Rinehart et al
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