27 research outputs found

    Physiological and biochemical characterization, of antimony stress, responses in Phaseolus vulgaris

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    Magister Scientiae - MSc (Biotechnology)The mining industry in South Africa is of immense importance as this sector contributes largely to the countries income. In the Limpopo province, a large production of antimony (Sb) is generated per year. Antimony (Sb) is a trace element, which accumulates in the environment through anthropogenic activities, such as mining and smelting industries. Antimony is toxic to all living organisms and plants, and it is found to increase the peroxidation of membrane lipids and encourage an antioxidant response. Sb contamination in plants also accounts for DNA damage. The reduction in yield is due to the disruption of plant metabolism by reactive oxygen species (ROS). To combat abiotic stresses, plants have generated a signalling network that utilises multiple growth regulators that would offer protection against the stress. An increase in ROS is one of the responses to abiotic stresses. ROS is generated in response to the pants interaction with heavy metals, through the Harber-Weiss reaction. ROS compounds include: superoxide, hydrogen peroxide and hydroxyl radicals. Under normal conditions ROS molecules are produced as by-products, however, under stressful conditions the production of ROS molecules are increased to levels where they are detrimental to the plants. Therefore, the accumulation of ROS results in damage to proteins, lipids, carbohydrates and DNA which would lead to cellular death. ROS accumulation is thought to be a result of the disruption in the balance of ROS production and the anti-oxidation systems. The antioxidative system is thus introduced to restore the balance of ROS molecule production and to combat oxidative damage caused by the ROS molecules. The anti-oxidative system consists of various enzymes: superoxide dismutase, catalase, and ascorbate peroxidase and glutathione reductase. Each antioxidant scavenges one or two ROS molecules

    Screens or MP4s: Acquiring Clinical Competencies Through the Use of e-OSPEs in Occupational Therapy

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    The assessment of clinical competence of undergraduate students is a crucial part of higher education training in occupational therapy. The use of online objective standardized practical examinations (e-OSPEs) was piloted as a technological innovation to determine student learning needs. An action research framework with four phases was used. Descriptive statistics in the form of frequency tables and percentages were used to report survey results. The students had multiple practice opportunities before uploading their best attempt. Thirty participants completed a 12-item survey. The results were analyzed using descriptive analysis and presented by means of statistical graphs. Peer assessment facilitated experiential learning. Twenty-seven out of 30 students (90%) felt adequately prepared for submitting their video clips. The students found the opportunity to practice the skills multiple times before uploading the e-OSPEs helpful. The students experienced an increase in workload when the e-OSPEs were due during clinical placement and examination periods. Additional resources are needed for creating initial infrastructure for implementing e-OSPEs. The findings of this study could inform the planning of future online assessment practices of clinical competencies in occupational therapy. Identifying, formulating, and assessing competence standards electronically may guide occupational therapy practitioners’ work with diverse patients and populations

    The Relationship between Cadmium Toxicity and the Modulation of Epigenetic Traits in Plants

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    Elevated concentrations of heavy metals such as cadmium (Cd) have a negative impact on staple crop production due to their ability to elicit cytotoxic and genotoxic effects on plants. In order to understand the relationship between Cd stress and plants in an effort to improve Cd tolerance, studies have identified genetic mechanisms which could be important for conferring stress tolerance. In recent years epigenetic studies have garnered much attention and hold great potential in both improving the understanding of Cd stress in plants as well as revealing candidate mechanisms for future work. This review describes some of the main epigenetic mechanisms involved in Cd stress responses. We summarize recent literature and data pertaining to chromatin remodeling, DNA methylation, histone acetylation and miRNAs in order to understand the role these epigenetic traits play in cadmium tolerance. The review aims to provide the framework for future studies where these epigenetic traits may be used in plant breeding and molecular studies in order to improve Cd tolerance

    Decoding heavy metal stress signalling in plants: Towards improved food security and safety

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    The mining of heavy metals from the environment leads to an increase in soil pollution, leading to the uptake of heavy metals into plant tissue. The build-up of toxic metals in plant cells often leads to cellular damage and senescence. Therefore, it is of utmost importance to produce plants with improved tolerance to heavy metals for food security, as well as to limit heavy metal uptake for improved food safety purposes. To achieve this goal, our understanding of the signaling mechanisms which regulate toxic heavy metal uptake and tolerance in plants requires extensive improvement. In this review, we summarize recent literature and data on heavy metal toxicity (oral reference doses) and the impact of the metals on food safety and food security. Furthermore, we discuss some of the key events (reception, transduction, and response) in the heavy metal signaling cascades in the cell wall, plasma membrane, and cytoplasm. Our future perspectives provide an outlook of the exciting advances that will shape the plant heavy metal signaling field in the near future

    Collaborative capacity development to complement stroke rehabilitation in Africa

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    This scholarly book focuses on stroke in Africa. Stroke is a leading cause of disability among adults of all ages, contributing significantly to health care costs related to long term implications, particularly if rehabilitation is sub-optimal. Given the burden of stroke in Africa, there is a need for a book that focuses on functioning African stroke survivors and the implications for rehabilitation within the African context. In addition, there is a need to progress with contextualised, person-centred, evidence-based guidance for the rehabilitation of people with stroke in Africa, thereby enabling them to lead socially and economically meaningful lives. The research incorporated in the book used a range of primary and secondary methodological approaches (scoping reviews, systematic reviews, meta-analyses, descriptive studies, surveys, health economics, and clinical practice guideline methodology) to shed new insights into African-centred issues and strategies to optimise function post-stroke

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Relatório de estágio em farmácia comunitária

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    Relatório de estágio realizado no âmbito do Mestrado Integrado em Ciências Farmacêuticas, apresentado à Faculdade de Farmácia da Universidade de Coimbr

    The Relationship between Cadmium Toxicity and the Modulation of Epigenetic Traits in Plants

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    Elevated concentrations of heavy metals such as cadmium (Cd) have a negative impact on staple crop production due to their ability to elicit cytotoxic and genotoxic effects on plants. In order to understand the relationship between Cd stress and plants in an effort to improve Cd tolerance, studies have identified genetic mechanisms which could be important for conferring stress tolerance. In recent years epigenetic studies have garnered much attention and hold great potential in both improving the understanding of Cd stress in plants as well as revealing candidate mechanisms for future work. This review describes some of the main epigenetic mechanisms involved in Cd stress responses. We summarize recent literature and data pertaining to chromatin remodeling, DNA methylation, histone acetylation and miRNAs in order to understand the role these epigenetic traits play in cadmium tolerance. The review aims to provide the framework for future studies where these epigenetic traits may be used in plant breeding and molecular studies in order to improve Cd tolerance
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