30 research outputs found

    Occurrence of cyanobacteria genera in the Vaal Dam: implications for potable water production

    Get PDF
    The occurrence of cyanobacteria genera in the Vaal Dam was analysed and the factors that influence its dominance in the particular reservoir were also investigated. The study was motivated by the effects of the secondary metabolites of cyanobacteria genera on potable water production. Cyanobacteria genera have been found to be potentially toxic and capable of producing taste and odour secondary metabolites such as geosmin. Historical data from the Department of Water and Sanitation on percentage composition of cyanobacteria genera in the Vaal Dam, were collected for the 2006, 2007, 2011 and 2012 years. The concentrations of NO2-N and NO3-N and total phosphorus as well as water temperature data were collected from the same sampling point for the study period. This data, together with weather data, was statistically analysed for trends and relatedness between variables. It was found that Microcystis and Anabaena were the dominant cyanobacteria genera in Vaal Dam and they were jointly dominant over other phytoplankton genera during February and March. It was also found that the dominance of cyanobacteria genera significantly correlated with air and water temperature and concentration of NO2-N and NO3-N. It was concluded that the dominance of Microcystis and Anabaena genera among the cyanobacteria genera has significant implications for potable water production as the genera are associated with taste and odour metabolites and toxins. It was recommended that depth profiling be employed in order to identify an abstraction depth in the multilevel intake of the reservoir with relatively low levels of cyanobacteria cells. This would assist in minimising taste and odour events in potable water production.Keywords: Anabaena, cyanobacteria dominance, environmental conditions, Microcystis, Vaal Dam, water treatment

    Randomized, parallel-group, double-blind, controlled study to evaluate the efficacy and safety of carbohydrate-derived fulvic acid in topical treatment of eczema

    Get PDF
    controlled study to evaluate the efficacy and safety of carbohydrate-derived fulvic acid in topical treatment of eczem

    Phase 1 clinical study of the acute and subacute safety and proof-of-concept efficacy of carbohydrate-derived fulvic acid

    Get PDF
    BACKGROUND: The purpose of this research was to determine the acute and subacute safety and proof-of-concept efficacy of carbohydrate-derived fulvic acid (CHD-FA). METHODS: In this double-blind study, 30 male volunteers with predetermined atopy were randomly assigned to either Group A or Group B, each consisting of 15 participants. In part 1 of the study, the groups were administered increasing amounts of CHD-FA, ranging from 5 mL to 40 mL, provided that no adverse events had occurred at the previous dosage. In part 2, Group A participants received 20 mL of 3.8% CHD-FA twice daily for 3 days and were monitored for a week. Because no adverse events occurred, Group B received 40 mL of 3.8% CHD-FA twice daily for a period of 3 days. In part 3, both groups received either 40 mL of 3.8% CHD-FA or placebo twice daily for a period of one week, followed by a one-week washout period before crossover to the alternative treatment schedule. Parameters used to establish safety were electrocardiography, a physical examination, a health questionnaire, and hematology and biochemistry, determined at baseline, during regular calculated intervals, and at the end of each part of the study. A skin prick test was done as part of the screening process and, from the result, the allergen the participant was most allergic to was then selected, along with the positive histamine and negative control to be repeated at the start and end of each respective stage. RESULTS: Safety parameters remained constant throughout the trial. A significant decrease in skin prick test results was observed. CONCLUSION: No severe adverse events occurred, establishing that CHD-FA to be safe at doses up to 40 mL twice daily for a week and that at this dosage CHD-FA acts as an anti-inflammatory agent. These findings confirm earlier animal data.http://www.dovepress.com/clinical-pharmacology-advances-and-applications-journa

    Potentiated clinoptilolite reduces signs and symptoms associated with veisalgia

    Get PDF
    INTRODUCTION : Abundant anecdotal evidence for products claiming to reduce veisalgia after alcohol overindulgence are available on the Internet and as many advertisements in journals. None of these claims are, however, substantiated by research. The aim of this research was to ascertain the validity of such claims for the substance Absorbatox™, a potentiated aluminosilicate (cation exchanger able to bind NH4+, histamine, and other positively charged ions) by investigating the signs and symptoms, as well as blood or breath alcohol levels, in healthy volunteers. METHODS : Blood or breath alcohol levels were measured in all volunteers in initial controlled experiments, and symptoms were scored on a diary card for gastrointestinal tract symptoms, as well as other symptoms such as headache and light sensitivity. Eighteen volunteers completed the initial blood alcohol study, which investigated the effect of Absorbatox™ on blood alcohol levels after fasting. The follow-up studies researched the effects of the symptoms and signs of alcohol overindulgence. The “night out” study was completed by ten volunteers in a typical controlled environment, which was followed by the real-life four-leg crossover study. In the crossover study, volunteers (number =25 completers) had to fill matching diary cards to containers of two placebo and two active drugs after a night out where they themselves decided on the container (color coded) to be used and the amount of alcohol to be consumed. RESULTS : Absorbatox™ had no effect on blood alcohol levels, but it significantly reduced the symptoms and signs of veisalgia by approximately 40%–50%. CONCLUSION : This research indicates that Absorbatox™ does not have an effect on blood- or breath-alcohol levels. Furthermore, treatment with Absorbatox™ resulted in an overall significant reduction in central nervous system and gastrointestinal tract symptoms associated with veisalgia, warranting further investigation.http://www.dovepress.com/clinical-and-experimental-gastroenterology-journalam201

    Potentiated clinoptilolite : artificially enhanced aluminosilicate reduces symptoms associated with endoscopically negative gastroesophageal reflux disease and nonsteroidal anti-inflammatory drug induced gastritis

    Get PDF
    PURPOSE : The cation exchanger, a potentiated clinoptilolite (Absorbatox™ 2.4D), is a synthetically enhanced aluminosilicate. The aim of this study was to evaluate the possible benefits of a potentiated clinoptilolite as a gastroprotective agent in reducing the severity of clinical symptoms and signs associated with 1) endoscopically negative gastroesophageal reflux disease (ENGORD) and 2) nonsteroidal anti-inflammatory drug (NSAID) medication. METHODS AND PATIENTS : Two randomized, double-blind, placebo-controlled, pilot studies, the ENGORD and NSAID studies, were conducted. After initial negative gastroscopy, a total of 25 patients suffering from ENGORD were randomized to receive either placebo capsules or 750 mg Absorbatox twice daily for 14 days. The NSAID study recruited 23 healthy patients who received orally either 1,500 mg Absorbatox or placebo three times daily, plus 500 mg naproxen twice daily. Patients underwent gastroscopic evaluation of their stomach linings prior to and on day 14 of the study. Gastric biopsies were obtained and evaluated via the upgraded Sydney system, whereas visible gastric events and status of the gastric mucosa were evaluated via a 0–3 rating scale. During both studies, patients recorded gastric symptoms in a daily symptom diary. RESULTS : In the ENGORD study, patients who received the potentiated clinoptilolite reported a significant reduction (P#0.05) in severity of symptoms including reduction in heartburn (44%), discomfort (54%), and pain (56%). Symptom-free days improved by 41% compared to the group who received placebo (not significant). This was over and above the benefits seen with the proton pump inhibitor. In the NSAID study, the reduction in gastric symptom severity was echoed in the group who received the potentiated clinoptilolite. Treatment with the potentiated clinoptilolite resulted in significant prevention (P#0.05) of mucosal erosion severity as graded by the gastroenterologist. CONCLUSION : Absorbatox is a nonabsorbable aluminosilicate with potential gastroprotective benefits as it protected against ENGORD symptoms and NSAID-induced gastric events. The exact mechanism of action is not clear but may be due to its binding to hydrogen ions and biologically active amines and nitrates.http://www.dovepress.comhb201

    Trends in pharmacotherapy selection for the treatment of alcohol withdrawal in the Free State Province, South Africa

    Get PDF
    Background.The selection of pharmacotherapy for the treatment of alcohol withdrawal remains a clinical challenge. Research continues into the underlying pathophysiology of dependence and withdrawal. A spectrum of clinical presentations of alcohol dependence is emerging, yet recommendations and guidelines have remained unchanged for some time.  Objectives. To engage with the problem of translating research into practice, as reflected by the selection of pharmacotherapy for alcohol withdrawal by medical practitioners in the Free State Province, South Africa. Methods. A questionnaire-based survey and interviews were conducted among 121 professionals in both the private and public sectors across the province. A subgroup was formed comprising the 58 doctors who indicated that they prescribe for alcohol withdrawal. Participants worked in private general practice, specialist psychiatry practice, in a state hospital or in a treatment centre. Results. Prescribing practices varied based on practitioners’ geographical distribution and professional capacity. Deviation from standard recommendations included the routine use of clothiapine and antidepressants in withdrawal regimens. Prescribing clothiapine appears to be a local custom. While prescription of antidepressants may indicate unrealistic expectations of therapeutic benefit, there are clear indications that this is maintained to mask the diagnosis of an alcohol-related condition. Prescribing for alcohol withdrawal is therefore not necessarily determined by pathophysiology or efficacy of medication. Conclusion. Withdrawal regimens need to be reassessed by researchers, policy makers and funders, balancing new developments with the real-life experiences and challenges of prescribers and their patients

    Use of Sustainable Materials in Self-Healing Concrete

    Get PDF
    Vulnerability to cracks is one of the major flaws of concrete infrastructure. The need to reduce the repair cost of this defect birthed the need for self-healing concrete. The incidence of cracks on concrete structures is a big threat to the stability of bridges, concrete roads, and other concrete infrastructures. This review assessed the use of self-healing technology on concrete using sustainable material as an active method of healing crack. This was done with the view of improving the stability, strength, and sustainability of infrastructure for national growth. The outcome of the review showed three prominent methods used in self-healing technology, which include autogenous healing, encapsulation of polymeric material, and microbial production of calcium-carbonate (biotechnological approaches). The review also revealed that calcium carbonate is a versatile material that can be used in crack healing for the filling of voids and improves the porosity of the concrete. The success of using the autogenous healing method depends on the diameter of the crack induced in the concrete structure. Additionally, this method can operate independently in different conditions regardless of the crack position. Correspondingly, lowering the water-cement ratio improves the autogenous healing process. The use of encapsulation of polymeric material and microbial production of calcium-carbonate methods showed that the presence of water and humidity is a critical factor to be considered. However, biotechnology using microbial action is prone to the production of ammonium ions (NH4+) through ureolytic activity, which results in nitrogen oxide emission into the atmosphere. Congruently, this may affect the durability of the concrete. Based on the uniqueness of this technology, it is recommended for the construction of sustainable infrastructure now and in the foreseeable future

    An observational trial : patient profile of users of Secomet V®

    Get PDF
    Subsequent to a report published by Natasha Bolognesi in Nature Medicine in 2006 on a “herbal” product called Secomet V® researchers of the University of Pretoria undertook an observational trial to document the demographics, quality of life and disease profile of patients who purchase Secomet V®, a product that contains selenium, L-glutamin and high levels of a carbohydrate derived fulvic acid (CHD-FA). No traces of any plant extracts could be found in the product

    A prospective, observational study comparing the PK/PD relationships of generic Meropenem (Mercide®) to the innovator brand in critically ill patients

    Get PDF
    INTRODUCTION : Clinicians’ skepticism, fueled by evidence of inferiority of some multisource generic antimicrobial products, results in the underutilization of more cost-effective generics, especially in critically ill patients. The aim of this observational study was to demonstrate equivalence between the generic or comparator brand of meropenem (Mercide®) and the leading innovator brand (Meronem®) by means of an ex vivo technique whereby antimicrobial activity is used to estimate plasma concentration of the active moiety. METHODS : Patients from different high care and intensive care units were recruited for observation when prescribed either of the meropenem brands under investigation. Blood samples were collected over 6 hours after a 30 minute infusion of the different brands. Meropenem concentration curves were established against United States Pharmacopeia standard meropenem (Sigma-Aldrich) by using standard laboratory techniques for culture of Klebsiella pneumoniae. Patients’ plasma samples were tested ex vivo, using a disc diffusion assay, to confirm antimicrobial activity and estimate plasma concentrations of the two brands. RESULTS : Both brands of meropenem demonstrated similar curves in donor plasma when concentrations in vials were confirmed. Patient-specific serum concentrations were determined from zones of inhibition against a standard laboratory Klebsiella strain ex vivo, confirming at least similar in vivo concentrations as the concentration curves (90% confidence interval) overlapped; however, the upper limit of the area under the curve for the ratio comparator/innovator exceeded the 1.25-point estimate, i.e., 4% higher for comparator meropenem. CONCLUSION : This observational, in-practice study demonstrates similar ex vivo activity and in vivo plasma concentration time curves for the products under observation. Assay sensitivity is also confirmed. Current registration status of generic small molecules is in place. The products are therefore clinically interchangeable based on registration status as well as bioassay results, demonstrating sufficient overlap for clinical comfort. The slightly higher observed comparator meropenem concentration (4%) is still clinically acceptable due to the large therapeutic index and should ally fears of inferiority.Ranbaxy (S.A) (Pty) Ltdwww.dovepress.comam2016Pharmacolog

    Permeable pavements for storm water control incorporating nano clay

    Get PDF
    Stormwater affects the economic situation of the environment, changes the land use, which also affects the ecosystem. Consequently, this affects the pavement condition of the road and lead to both structural and functional pavement defects. In a bid to proffer solution to the harmful effects of stormwater and reduce the cost of pavement construction in track with sustainability, this research utilized nano clay in the development of permeable concrete. The nano clay was used as a partial replacement for cement. It was dehydroxylated at 720°C; the characterization and particle geometry was done using the XRF equipment. The de-hydroxylated nano clay was used as a partial replacement for cement at 5, 10, 15, 20 and 25%. Correspondingly, six samples of concrete were developed. The mechanical properties (compressive and flexural strength) of the permeable concrete was assessed at 3, 7, 14, 21 and 28 days. Additionally, the porosity of the concrete was determined using Archimedes principle. The result of the research showed that using nano clay replacement at 15% gave a flexural strength of 4.01MPa. This is lower than the required specification of 4.27Mpa—4.5MPa for pavement construction at 28 days and 4.5Mpa and above for airfield pavement. The porosity test using Archimedes principle showed a satisfactory result. This proves the efficiency of the concrete for stormwater control. Therefore, this concrete is recommended for use in the design and construction of low axle or low trafficked road for stormwater control and aquifer recharge based on the flexural strength
    corecore