In vitro propagation of Hypoxis rooperi from flower buds

Callus was initiated from young unopened flower buds of Hypoxis rooperi S. Moore when wounded and cultured on a basal medium supplemented with 1-naphthalene acetic acid (0,001g dm−3) and 6-benzylaminopurine (0,005g dm−3).Continuous callus production was obtained if the tissue was maintained on this medium. When transferred to a basal medium free of hormones, root formation occurred. Large numbers of shoots were initiated on the callusing flower buds by decreasing the 6-benzylaminopurine in the basal medium from 0,005g dm−3 to 0,001g dm−3. These shoots rooted readily on a hormone free medium. Seventy five per cent of the rooted plantlets were successfully established in vitro

Profile of the geriatric patients hospitilised at Universitas hospital, South Africa

Background: The elderly population in Africa is unevenly distributed across the continent, with the highest percentage of elderly living in the Southern African region. In 1996, the elderly population of South Africa (65 years and older) was roughly 6.7%, and was calculated to be 10.4% by 2025. If the latter expectation is anywhere near realistic, it stands to reason that the Department of Health should make timely provision for the care of these future patients, as the prevailing disease patterns within a population change as that population ages. Thus, there is an urgent need for profiles of elderly patients in order for adequate training to be implemented and for beds and equipment to be ready when needed. Methods: A retrospective study was undertaken of all data available from a clinical audit done at Universitas Hospital's Geriatric Unit. All patients aged 65 years and older who were admitted by Internal Medicine's Geriatric Unit over four years were analysed in order to compile a profile of geriatric patients hospitalised at Universitas Hospital. Results: The study group consisted of 791 elderly patients. Their average age was 81 years (range: 65 to 101 years of age) and they were hospitalised for an average of 11 days, with an average use of five medications per patient. Women represented 66% of the patients and the mortality rate was 17% in the total study group. The main admitting clinical problems were hypertension, heart failure, ischemic heart disease and anaemia. Most of the patients did not smoke or use alcohol. Out of a group of 523(due to the fact that it was a retrospective study, data for this criteria were only available for 523 of the 791 patients), 235 (45%) were self-supporting and 32% were known to use living aids. The majority of the patients were single and an equal amount were living in old age homes and with their families. The main special examinations used in their treatment were chest X-rays, nuclear examinations of the liver, ECG, heart sonar and CT of the brain, and gastroscopies. Almost all of the patients had undergone full blood count analysis and U+E determinations, and in more than 50% of cases, creatine, albumin and glucose measurements were taken. Conclusion: For successful geriatric care at Universitas Hospital there will be a need for at least 11 days hospitalisation, and a unit with good training in internal medicine, psychiatry, urology, orthopaedy and oncology. The main supporting services will be physiotherapy, occupational therapy and social welfare. Laboratory analyses will include full blood count, urea and electrolyte measurements, urine examination, and creatine and glucose measurements. Special investigations will mainly be radiology and cardiology sonar examination. How well we care for elderly patients in the future will be an indicator of the quality of our healthcare system in general. We need to redesign our social insurance and welfare systems to fit the realities of our current situation. South African Family Practice Vol. 49 (2) 2007: pp. 1

Malic Acid Distribution and Degradation in Grape Must During Skin Contact: The Influence of Recombinant Malo-Ethanolic Wine Yeast Strains

Wine acidity plays an important role in determining wine quality and ensuring physiochemical and microbiological stability. In high-acid wines, the L-malic acid concentration is usually reduced through bacterial malolactic fermentation, while acidulation in low-acidity wines is usually done during final blending of the wine before bottling.  This study showed that skin contact did not influence the relative concentration of L-malic acid in the pulp and juice fractions from Colombard, Ruby Cabernet and Cabernet Sauvignon grape musts, with 32%-44% of the L-malic acid present in the pulp fraction. Four recombinant malo-ethanolic (ME) Saccharomyces wine yeast strains containing the malic enzyme (mae2) and malate transporter (mael) genes of Schizasaccharomyces pombe, effectively degraded the L-malic acid in both the juice and pulp fractions of all three cultivars, with a complete degradation of malic acid in the juice fraction within 2 days

A systematic review of language and literacy interventions in children and adolescents with English as an additional language (EAL)

This systematic review presents a synthesis of evidence regarding the effectiveness of language and literacy interventions targeting children with EAL. It updates the systematic review by Murphy and Unthiah [2015. A systematic review of intervention research examining English language and literacy development in children with English as an additional language (EAL). http://www.naldic.org.uk/Resources/NALDIC/Research and Information/Documents/eal-systematic-review-prof-v-murphy.pdf.], using the same methodology. Four databases were searched resulting in 2217 records identified. After screening 25 interventions, found in 26 studies, were eligible for inclusion. The results provide collective evidence that explicit vocabulary instruction and targeted oral language practice yield language gains for EAL learners, with a tendency for larger intervention gains in learners with the lowest initial pre-test scores. Shared reading interventions show positive effects when combined with the pre-teaching of vocabulary, embedded definitions into the text, or post-reading reinforcement activities. The review also highlights the paucity of interventions in the UK and in particular, a lack of interventions for adolescents, especially those in upper secondary school (ages 14-18)

Genetic Engineering of an Industrial Strain of Saccharomyces cerevisiae for L-Malic Acid Degradation via an Efficient Malo-Ethanolic Pathway

The optimal ratio of L-malic and L-tartaric acid in relation to other wine components is one of the most important aspects that ultimately determine wine quality during winemaking. Winemakers routinely rely on the judicious use of malolactic fermentation (MLF) after alcoholic fermentation to deacidify and stabilise their wines. However, due to theunreliability of the process and unsuitable sensory modifications in some grape cultivars, especially for fruity-floral wines, MLF is often regarded as problematic and undesirable. Alternative methods for reducing the amounts of L-malic acid in wine will contribute to improving the production of quality wines in the future, especially in coolclimate regions. Most wine yeast strains of Saccharomyces are unable to effectively degrade L-malic acid, whereas the fission yeast Schizosaccharomyces pombe efficiently degrades high concentrations of L-malic acid by means of malo-ethanolic fermentation. However, strains of S. pombe are not suitable for vinification due to the production of undesirable off-flavours. Previously, the 5. pombe malate permease (mael) and malic enzyme (mae2) genes were  successfully expressed under the 3-phosphoglycerate kinase (PGK1) regulatory elements in 5. cerevisiae, resulting in a recombinant laboratory strain of S. cerevisiae with an efficient malo-ethanolic pathway. Stable integration of the S. pombe malo-ethanolic pathway genes has now been obtained through the construction of a unique integration strategy in a commercial wine yeast strain. Co-transformation of the linear integration cassette containing the mael and mae2 genes and PGK1 regulatory elements and a multi-copy plasmid containing the phleomycin-resistance marker into a commercial Saccharomyces cerevisiae strain resulted in the successful transformation and integration of the malo-ethanolic genes. The recombinant 5. cerevisiae strain was successfully cured of phleomycin-resistance plasmid DNA in order to obtain malo-ethanolic yeast containing only yeast-derived DNA. The integrated malo-ethanolic genes were stable in 5. cerevisiae and during synthetic and grape must fermentation, L-malic acid was completely fermented to ethanol without any negative effect on fermentation kinetics and wine quality

Assessments and improvement of filter media cleanliness in rapid gravity sand filters

Introduction: Rapid sand filtration is an essential unit process in the water purification process. It captures and removes coagulated and flocculated material and other suspended matter not removed during the preceding treatment processes. The pores in the filter bed gradually become clogged and the media progressively collects deposit through the continuous use and life of the filter. During normal operations cleaning is initiated by excessive head loss, deterioration in filtrate quality or when the predetermined time for a filter run has elapsed. Air scour, to remove deposit from filter media by vigorous agitation, and wash water, to remove this deposit from the filter bed, are applied. The combined action of air and water should quickly return the media to its original perfectly clean state for the cycle to continue. However, on inspection it is often found that filter sand on purification plants is unacceptably dirty and backwash systems are clearly incapable of cleaning the media to its initial state of cleanliness. It is at times possible to relate the dirty filter media to faulty designs or poor operating procedures, but often the reasons for the media deterioration remain elusive and the media becomes dirtier the longer it is in use. As there was an almost complete lack of published or agreed upon procedures to measure the cleanliness of filter media, rudimentary methods for measuring filter media cleanliness and backwash efficiency were developed. Thereafter filter media from full-scale treatment plants was analyzed with these methods at regular intervals to establish some benchmarks for these determinants. These methods were also applied during the laboratory and pilot plant phases of the project

Synthesis, X-ray structure determination and germination studies on some smoke-derived karrikins

AbstractThe discovery of the karrikin class of plant growth regulators (PGRs) is a milestone accomplishment in plant biochemistry and physiology, with significant potential in agriculture and horticulture. These compounds have in common a fused furano-pyran ring system featuring various permutations of methyl substitution. Chief amongst these compounds is karrikinolide (KAR1), identified as the key germination stimulant present in plant-derived smoke, which together with five other closely-related structures (KAR2–KAR6) make up the karrikin class of PGRs. By contrast, the germination inhibitor 3,4,5-trimethyl-2(5H)-furanone has also been identified in plant-derived smoke. Various synthetic endeavours have been undertaken for structure–activity relationship study purposes as well as to probe the molecular mechanics of these compounds. In this study, syntheses of KAR1, KAR3 and S-KAR1 were carried out and their structures verified by X-ray crystallography. Effects on germination were measured against the inhibitor 3,4,5-trimethyl-2(5H)-furanone in Grand Rapids lettuce seeds. X-ray crystallographic data and germination promotory activity for S-KAR1 are described for the first time

Potential medicinal value of some South African seaweeds

Eleven macroalgae were collected from the KwaZulu-Natal coast and nineteen species from the cooler Western Cape coast in March and April 2000. Ethanolic and aqueous extracts were made and tested for biological activity in the Cox-1 anti-inflammatory assay, in a nematode mortality bioassay for anthelminthic activity, an IC50 anticancer assay and a MIC antimicrobial assay. The ethanolic extracts were very active in the Cox-1 anti-inflammatory assay for almost all of the species tested. The aqueous extracts were not active. No anthelminthic mortality was detected in extracts from any of the species tested. Many of the extracts had cytotoxic activity against three cancer cell lines tested, with those from representative species of the Chlorophyta and Rhodophyta being the most effective. The extracts had much lower cytotoxic activity when tested on normal mouse fibroblasts (NIH3T3). Extracts from only a few species had antimicrobial activity with those of the Chlorophyta tested being the most effective against both the Gram-positive and Gram-negative bacteria

Disclosure responses to mining accidents : South African evidence

Mining activities generate significant social concerns in terms of employee safety and stakeholder scrutiny has increased considerably in recent years. Social and environmental accounting research is largely dedicated to environmental issues and the study of other components of social accounting is limited. This study examines safety disclosures in the annual reports, sustainability reports, and reactive corporate press releases of South African mining organisations following two major mining accidents occurring at Harmony Gold and Gold Fields’ mines. Results show that organisations react to perceived legitimacy threats through increased safety disclosures. The entire mining industry evidences an increase in disclosure levels after the incidents, suggesting that organisations do respond to increased stakeholder scrutiny threatening their legitimacy. Furthermore, our results provide evidence of an association between safety disclosure levels and firm size, social performance, risk, and number of fatalities, while the media attention devoted to mining accidents appears to be unrelated to safety disclosure levels. It is possible that stakeholder pressure, which motivates corporate social disclosures according to legitimacy and stakeholder theories, consists of various factors, which combined form the motivation to report. Media attention, therefore, cannot be considered in isolation as a driver of disclosure. Rather, a combination of variables such as size, social responsibility performance, number of fatalities, risk, and media attention could serve as a proxy for social pressure.http://www.elsevier.com/locate/accfo

Antimicrobial Activity, Phenolic Content, and Cytotoxicity of Medicinal Plant Extracts Used for Treating Dermatological Diseases and Wound Healing in KwaZulu-Natal, South Africa

Medicinal plants used for wound healing and skin diseases are the key to unlocking the doors to combating problematic skin diseases as resistance of pathogens to pharmaceuticals and allopathic management continues to increase. The study aimed at investigating the antimicrobial efficacies, phenolic content and cytotoxicity effects of eleven medicinal plant extracts commonly used for treating skin conditions and wound healing in traditional medicine within KwaZulu-Natal. Eleven plant species were separated into different plant parts (bulbs, roots, leaves) and extracted with different solvents. The extracts were assessed for antimicrobial activity against six Gram-positive and seven Gram-negative bacterial strains and four fungi commonly associated with skin conditions using disc diffusion and microdilution techniques. The aqueous methanolic extracts were screened for phenolic content while cytotoxicity tests were performed on all extracts using the brine shrimp lethality and tetrazolium–based colorimetric (MTT) assays. Extracts from Aloe ferox, A. arborescens and Hypericum aethiopicum were the most active against almost all of the tested bacterial and fungal strains. All plant species exhibited some degree of antimicrobial activity. Total phenolic levels, flavonoids and tannins were also higher for A. ferox, followed by A. arborescens and H. aethiopicum respectively. The cytotoxicity results of all plant extracts were in the range of 90-100% survival after 24 h in the Brine shrimp assay. Extracts considered lethal would demonstrate > 50% shrimp death. The MTT cytotoxicity test yielded LC50 values of > 1 mg/mL on all extracts indicating that they are not cytotoxic. The observed antimicrobial efficacy demonstrated by some plant species and the general lack of cytotoxic effects on all the tested extracts presents some promising and beneficial aspects of these medicinal plant extracts in the treatment of skin diseases and wound healing. The two Aloe species and H. aethiopicum were among the best extracts that exhibited consistently good antimicrobial activity and warrants further investigations and possible isolation of bioactive principles