ABSTRACT
Cyanobacteria produce toxins that are harmful to humans. They are found mostly in surface water, which is the main water source for drinking water before treatment. However, most of the water treatment plants are inadequate to treat toxins such as microcystins in raw water sources from contaminated surface water that has blooming and/or decaying cyanobacteria. Microcystins are harmful toxins produced by cyanobacteria that cause both acute and chronic health problems in humans. However, little is known about microcystins in water containers at the household level. This article therefore focuses on a review of the effects of microcystins in drinking water containers at the household level, including types of microcystins, their health effects, and cases reported in both animals and humans. Therefore, there is a need to develop the water quality management for cyanobacteria toxins, particularly microcystins in household containers.
Subject(s)
Cyanobacteria , Drinking Water , Water Purification , Animals , Humans , Microcystins/toxicity , Cyanobacteria ToxinsABSTRACT
Women infected with the human immunodeficient virus have a higher risk of pelvic inflammatory disease, which could lead to development of ectopic pregnancy due to fallopian tubal pathology. Due to short pregnancy period, women with ectopic pregnancy unlikely complete the antenatal screening, which includes HIV tests. Therefore, it is postulated that unscreened HIV infection prevalence in women with ectopic pregnancy diagnosis could be significantly higher than in women with normal intrauterine pregnancy (IUP). The aim of the present retrospective cross-sectional study was to determine the association between ectopic pregnancy and HIV infection in KwaZulu Natal Province hospital setting, between 2016 and 2017. 5427 pregnant women with normal pregnancies formed the intrauterine pregnancy (IUP) cohort, while 83 patients were part of the ectopic pregnancy cohort. The statistical HIV prevalence was significantly higher in the ectopic pregnancy cohort (56.63% vs 39.4%, P-value of 0.001). In addition, HIV prevalence in the ectopic pregnancy cohort was analyzed per age group, and it was found to be higher in the 25-34 years age group (88.3%) than the 16-24 (43.3%) and 35-42 (60%) years age groups. This study highlights the significance of conducting a full antenatal screening programme in patients who present with ectopic pregnancy, to improve the rate of HIV infection testing and treatment in women who present with ectopic pregnancy.
Subject(s)
HIV Infections , Pregnancy, Ectopic , Pregnancy , Female , Humans , Adult , HIV Infections/epidemiology , Retrospective Studies , Prevalence , Cross-Sectional Studies , Pregnancy, Ectopic/epidemiologyABSTRACT
BACKGROUND: Medical students are under immense academic stress. Campus unrest can contribute to stress and influence academic performance, social behaviour, emotional stability and financial expenses. OBJECTIVES: To investigate the effects of #FeesMustFall2016 (#FMF2016) on the 2016 3rd-year (semester 6) clinical medical students at the University of the Free State (UFS), Bloemfontein, South Africa. METHODS: In phase 1 of the project, anonymous questionnaires were completed by the clinical students who experienced physical test disruption during #FMF2016. Opinions regarding academic performance, financial expenses, behaviour changes and stress levels were gathered. The students also completed a formal post-traumatic stress screening assessment. In phase 2 of the project, the academic performance of these students was compared with that of students not affected by #FMF2016. RESULTS: Of the target population of 138 students, 87.0% completed the questionnaires. Three-quarters of the respondents reported a negative effect on academic performance, and most did not believe that the delivering of lectures on Blackboard was a good way of training. Alcohol consumption increased in 31.9% of the students. Criteria for post-traumatic stress disorder (PTSD) were met in 12.7% of students. Compared with previous and later cohorts of students there were no clear differences regarding marks, but there was a tendency towards poorer performance and more failures the next year. CONCLUSIONS: Semester 6 medical students at UFS reported that the #FMF2016 protests had a negative effect on academic, social, financial and stress aspects. PTSD was present in 12.7% of students compared with 7.8% in similar populations.
Subject(s)
Dissent and Disputes , Schools, Medical/economics , Stress, Psychological/etiology , Students, Medical/psychology , Academic Performance/psychology , Adult , Alcohol Drinking/epidemiology , Female , Humans , Male , South Africa/epidemiology , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/epidemiology , Surveys and Questionnaires , Young AdultABSTRACT
Several experimental and animal studies have demonstrated that substances rich in antioxidants can reduce the physicochemical and peroxidative risk factors for calcium oxalate (CaOx) renal stone formation in urine and blood. However, there are very few such investigations in humans. In the present pilot study, two varieties of tea, a green one from Japan (JGT) and a herbal one from South Africa (Rooibos) (RT), both rich in antioxidants, were administered to a group of CaOx stone formers (SF) (n = 8) for 30 days. Both teas were analysed for polyphenols by high-performance liquid chromatography and for minerals by plasma atomic and optical emission spectroscopy. 24 h urines (baseline and day 30) were analysed for lithogenic factors. CaOx metastable limits and crystal nucleation and growth kinetics were also determined in each urine sample. Deposited crystals were inspected by scanning electron microscopy. Blood samples were collected (baseline and day 30). Biomarkers of oxidative stress including plasma and urinary thiobarbituric acid reactive substances (TBARS) and urinary N-acetyl-ß-D-glucosaminidase (NAG) were also determined. Urinary physicochemical risk factors were also investigated after ingestion of RT for 30 days in two control groups (CG1 and CG2), the latter one of which consisted of habitual JGT drinkers. Statistical analyses were performed using Wilcoxon signed rank tests and Mann-Whitney tests for paired and independent measurements, respectively. Several flavonoids and catechins were quantified in RT and JGT, respectively, confirming that both teas are rich sources of antioxidants. Mineral content was found to be far below dietary reference intakes. There were no significant changes in any of the urinary physicochemical or peroxidative risk factors in the control groups or in SF, except for the supersaturation (SS) of brushite (Bru) which decreased in the latter group after ingestion of JGT. Crystal morphology showed a tendency to change from mixed CaOx mono- and di-hydrate to monohydrate after ingestion of each tea. Since the latter form has a stronger binding affinity for epithelial cells, this effect is not protective. Analysis of the physicochemical and peroxidative risk factors in CG1 and CG2 did not reveal any evidence of a synergistic effect between the two teas. Paradoxically, baseline risk factors in the habitual JGT control group were significantly raised relative to those in CG1. Our preliminary results suggest that ingestion of RT and JGT does not reduce the risk factors for CaOx stone formation in humans, but these findings need to be tested in further studies involving much larger sample sizes.
Subject(s)
Antioxidants/analysis , Antioxidants/therapeutic use , Nephrolithiasis/epidemiology , Nephrolithiasis/prevention & control , Tea/chemistry , Teas, Herbal/analysis , Adolescent , Adult , Chemical Phenomena , Humans , Male , Oxidation-Reduction , Pilot Projects , Risk Factors , Young AdultABSTRACT
The industrial production of short-chain fructooligosaccharides (FOS) and inulooligosaccharides is expanding rapidly due to the pharmaceutical importance of these compounds. These compounds, concisely termed prebiotics, have biofunctional properties and hence health benefits if consumed in recommended dosages. Prebiotics can be produced enzymatically from sucrose elongation or via enzymatic hydrolysis of inulin by exoinulinases and endoinulinases acting alone or synergistically. Exoinulinases cleave the non-reducing ß-(2, 1) end of inulin-releasing fructose while endoinulinases act on the internal linkages randomly to release inulotrioses (F3), inulotetraoses (F4) and inulopentaoses (F5) as major products. Fructosyltransferases act by cleaving a sucrose molecule and then transferring the liberated fructose molecule to an acceptor molecule such as sucrose or another oligosaccharide to elongate the short-chain fructooligosaccharide. The FOS produced by the action of fructosyltransferases are 1-kestose (GF2), nystose (GF3) and fructofuranosyl nystose (GF4). The production of high yields of oligosaccharides of specific chain length from simple raw materials such as inulin and sucrose is a technical challenge. This paper critically explores recent research trends in the production and application of short-chain oligosaccharides. Inulin and enzyme sources for the production of prebiotics are discussed. The mechanism of FOS chain elongation and also the health benefits associated with prebiotics consumption are discussed in detail.
Subject(s)
Inulin/metabolism , Oligosaccharides/biosynthesis , Prebiotics , Bacteria/enzymology , Fructans/chemistry , Fructans/classification , Fructans/metabolism , Fructose/chemistry , Fructose/metabolism , Fungi/enzymology , Glycoside Hydrolases/metabolism , Hexosyltransferases/metabolism , Inulin/chemistry , Oligosaccharides/metabolism , Sucrose/metabolism , Trisaccharides/metabolismABSTRACT
Plastic containers in the range of 5-20 L are widely used - especially in rural African settings - to collect, transport and store water for domestic use, including drinking, bathing and hygiene. The pathogen content of the waters in these containers has not been adequately characterized as yet. This paper presents the primary findings of a synoptic survey of drinking water quality samples from these containers and involved collection of bacterial indicator and pathogenicity gene data. In total, 571 samples of a variety of waters were taken in rural communities in South Africa and the Escherichia coli numbers measured. Of the E. coli positive samples, 46% (n = 148) were screened for the presence of E. coli pathogen gene markers. Though synoptic, the survey provided many insights into the issues that drove the study. Container use markedly degraded water quality as judged by indicator counts, even where improved water supply services were in place. Household container use also appeared to promote regrowth or contamination of containers with pathogenic E. coli strains. Polymerase chain reaction (PCR) analysis also showed that the diversity of potential pathogenic E. coli carrying virulence genes was great. All seven genes screened for (Ial, Stx1, Stx2, EaeA, Eagg, ST, LT) were found in the waters, alone or as mixtures (number of different combinations = 31) including those characteristic of the more dangerous invasive and haemorrhagic E. coli strains. Given the central role of containers in the management of water supply to rural communities, it is clear the microbiology of these waters requires much further characterization.
Subject(s)
Escherichia coli/isolation & purification , Household Articles , Water Microbiology , Water Supply/statistics & numerical data , Escherichia coli/genetics , Escherichia coli/pathogenicity , Genes, Bacterial , Humans , Rural Population , South AfricaABSTRACT
There is still debate and uncertainty in the literature about the health benefits of community water supply interventions. This paper reports on a changing incidence of self-reported diarrhoea associated with the implementation of two community water supplies. We conducted prospective weekly recording of diarrhoeal disease in three communities. Two of the communities were scheduled to receive an improved water supply and one was expected to continue to rely on an unimproved source during the study period. Data of self-reported diarrhoea was collected from each participating household on a weekly basis for up to 56 weeks, of which some 17 weeks were prior to implementation of the new water supply systems. Data was modelled using Generalized Estimating Equations (GEE) to account for possible clustering within households and within villages. For the two intervention communities in the study, the incidence rate ratio (IRR) for all ages after the intervention was 0.43 (95% CI 0.24-0.79) when compared to the control community (who did not receive an intervention), implying a 57% reduction of diarrhoea. Both of the new water systems were unreliable, one not operating on 4 weeks and the other on 16 weeks. The more reliable of the two intervention systems was also associated with less illness than in the least reliable system (IRR=0.41, 95% CI 0.21-0.80). We also noted anecdotal reports that during supply failures in the new systems some people were starting to use household water treatment. The implementation of improved water systems does appear to have been associated with a reduction of diarrhoeal disease in the communities. However the health impact was most obvious in the community with the more reliable system. Further research needs to be done to determine whether public health gains from community water supply interventions can be leveraged by occasional use of household water treatment (HWT) during supply failures.
Subject(s)
Diarrhea/epidemiology , Environmental Exposure/adverse effects , Public Health/methods , Water Pollution , Water Purification , Water Supply/standards , Family Characteristics , Incidence , Models, Biological , Prospective Studies , Residence CharacteristicsABSTRACT
BACKGROUND: Nearly 50% of South African children lack access to clean safe water and many regularly carry water loads. The health effects of carrying water have not been well researched or considered when estimating the burden of disease due to suboptimal water supply. Improved access to safe water has potential to create important health and economic benefits, by reducing childhood exposure to risk factors for injury or disease. The aim of this study was to identify which domains of health children perceive as affected by water carrying. METHODS: Qualitative research was used within a broader mixed methods design to investigate children's perceptions about health and water carrying in Limpopo Province, South Africa. Qualitative data from eight semi-structured interviews and three 'natural group meetings', involving a sample of 30 children, were analysed using the framework approach of Ritchie and Spencer. The results were mapped to the International Classification of Functioning Disability and Health (ICF). RESULTS: Children broadly conceptualize and describe health to include the functions they perform and activities in which they participate. They perceived water carrying as impacting upon health in various ways, for example to make life better by facilitating water usage, or to make life worse through accidents and pain. Children's accounts demonstrate that they can identify and explain complex interactions between activities, participation and health. CONCLUSIONS: The ICF framework facilitates the communication of children's perceptions of health and of relationships between health and water carrying. The model thus derived from their views incorporates not only commonly accepted conceptualizations of health condition, body structure and physiological function, but also of functioning through activities and social participation. Children's accounts suggest a possible association between water carrying and symptoms typical of musculoskeletal disorders. However, further research into the strength of association between water carrying and musculoskeletal disorders is needed.
Subject(s)
Lifting/adverse effects , Musculoskeletal Diseases/psychology , Pain/psychology , Physical Endurance/physiology , Water Supply , Weight-Bearing/physiology , Adolescent , Child , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Musculoskeletal Diseases/etiology , Pain/etiology , Rural Health , Severity of Illness Index , Social Environment , South Africa , WaterABSTRACT
AIMS: Aflatoxin B(1) (AFB(1)) is a mycotoxin which is known to frequently contaminate poorly stored food products destined for human consumption. This study was carried out to investigate the potential activity of lactic acid fermentation in reducing AFB(1) level in fermented maize meal products. METHODS AND RESULTS: Maize meal was spiked with 60 mug g(-1) AFB(1) and fermented, with or without starter culture, for 4 days at 25 degrees C. Unbound AFB(1) in solution and the pH of the media were monitored daily. A significant decrease (P < 0.05) in the level of unbound AFB(1) was observed (75% in the fourth day). Simultaneously, a progressive decrease in the pH of the media from 6.5 to 3.1 was also observed. AFB(1) was below the detection limit in commercial fermented porridge (amahewu) samples. Cytotoxicity tests on AFB(1)-spiked fermented extracts showed that those with a starter culture were comparatively less toxic (30-36%) than those with no added starter culture (24-30%). However, this difference was not significant (P > 0.05). CONCLUSIONS: These results indicate that lactic acid fermentation can significantly reduce the concentration of AFB(1) in maize to trace levels. However, the safety of fermented products has not been well studied, as the mechanism of AFB(1) removal is not well understood. SIGNIFICANCE AND IMPACT OF THE STUDY: Natural fermentation may potentially reduce exposure to natural toxins occurring in food.