Molecular analysis of fruit ripening: The identification of differentially expressed sequences in Vitis vinifera using cDNA-AFLP technology

Differential gene expression patterns were studied during the ripening process of grape berries (Vitis vinifera cv. Chardonnay). Thirty PstI + MseI primer combinations were used to generate 213 fragments that appeared to be differentially expressed of which 94 % were successfully re-amplified. Reverse northern dot-blot analysis indicated that 35 % of the fragments had similar gene expression profiles to cDNA-AFLPs regarding developmental-stage specificity. Northern blot analyses confirmed the tissue and/or developmental stage specific expression of three of these cDNA fragments. This work illustrates that developmentally regulated sequences can be identified from grape berry tissue using cDNA-AFLP technology

Enterococcal endocarditis - a case treated with teicoplanin and amoxycillin

The study aimed to determine the antibacterial therapy effective in the cure of endocarditis caused by Enterococcus faecalis resistant to clinically achievable levels of vancomycin. Isolation of the causative enterococcus had been achieved by direct inoculation of the resected valve into the culture medium in theatre. The patient was known to have had an aortic valve defect since childhood and had recently undergone splenectomy following trauma. Blood cultures were negative prior to valve replacement. A perivalvular abscess was noted at operation. In vitro minimal bactericidal results and serum activity were the basis of the postoperative choice of drugs. The minimal bactericidal level of teicoplanin was 250 µg/ml and that of amoxycillin 64 µg/ml. Neither is achievable with the advocated dosage. A combination of these two cell-wall-active agents successfully eliminated the infection. Acting at two different sites in the synthesis of the bacterial cell wall, teicoplanin and amoxycillin were found to be bactericidal in vitro at the trough levels of the antibiotics in the serum. The patient recovered fully

Anaerobic ammonium oxidation in the old trickling filters at Daspoort Wastewater Treatment Works

The century-old trickling filters at the Daspoort Wastewater Treatment Works in Pretoria (Gauteng, South Africa) are known for their remarkable removal of nitrogen from municipal wastewater. Our study was conducted to identify the microbiological processes responsible for this phenomenon and to establish whether anammox bacteria may be involved. An aerobic and anaerobic bench top reactor, both inoculated with biofilm-covered stones from one of the filters, were spiked with ammonia-nitrogen  (NH4+-N) and nitrite-nitrogen (NO2.-N). These reactors were subsequently monitored by conducting stoichiometric analyses of chemical oxygen demand (COD), NH4+-N, NO2.-N, and nitrate-nitrogen (NO3.-N). In the aerobic reactor, the COD concentration decreased over the 56 h batch reaction period and nitrification was revealed by a decrease in NH4+-N and NO2.-N concentrations. However, the NO3.-N concentration showed no  notable decrease. In contrast, in the anaerobic reactor the concentrations of COD, NH4+-N, NO2¡¥-N, NO3¡¥-N, as well as total nitrogen decreased during the batch reaction period. The decrease of both the NH4+-N and NO2.-N concentrations, the latter to zero under anaerobic conditions,   suggested that, in addition to heterotrophic denitrification, anaerobic ammonium oxidation (anammox) may also occur in the trickling filter biofilm. This was highlighted by the observation that ammonium removal in the anaerobic reactor stopped as soon as the nitrite concentration  became zero. The ratio of nitrite:ammonium removal was 1.33 on  average, which conforms to anammox behaviour. Gene sequence analysis was used to test for the possible presence of anammox bacteria in the  trickling filter biofilm. Genomic DNA was extracted from trickling filter  humus sludge and the polymerase chain reaction (PCR) was used to  amplify taxonomically informative 16S rRNA gene sequences, using  primers specific for selected anammox species. Subsequent sequence analysis, including using the online Basic Local Alignment Search Tool (BLAST), and constructing a phylogenic tree using a heuristic search  strategy for Maximum Parsimony analysis, confirmed the presence of an anammox bacterium closely related to Candidatus ¡®Brocadia  anammoxidans¡¯ and Candidatus ¡®Brocadia fulgida¡¯ on the biofilm-covered stones of the Daspoort trickling filters.Keywords: Daspoort, trickling filter, anammox, nitrification, denitrification, stoichiometric analyses, polymerase chain reactio

Desktop Analysis and Qualitative Investigation of Programmes and Initiatives for the Prevention of and Response to Gender Based Violence at South African Universities with Medical Campuses

Gender-based violence (GBV) is pervasive at South African higher education institutions (HEIs). Based on a media statement (dated 6 October 2016) by the Department of Higher Education and Training, GBV programmes at HEIs need to be evidence-informed, responsive, contextually relevant, inclusive and person-centred. The present article aims to explore the nature of GBV programmes currently implemented at HEIs in South Africa. A rapid review of the literature, supported by qualitative interviews with representatives of South African HEIs with medical campuses, was conducted. Findings indicate that there is an urgent need to clearly define GBV and to mention it explicitly in policy documents. In addition, research evidence on the effectiveness of prevention and response interventions at HEIs in South Africa is lacking. Challenges highlighted by the HEIs that were surveyed include the lack of trust by staff and students in the response and action plans of the response/task teams at HEIs, uncertainty with regards to the roles of relevant stakeholders and sectors when reporting incidents, as well as insufficient information about what GBV is. This study is intended to provide a baseline for further research evaluating current GBV programmes on medical campuses at HEIs, and highlights the need for an evidence-informed framework of the key ingredients for effective GBV response and prevention programmes

Xylem as well as phloem sustains severe damage due to feeding by the Russian wheat aphid

Investigation of comparative effects of feeding damage by the Russian wheat aphid (RWA, biotype SA1, Diuraphis noxia Mordvilko) on leaf blades of susceptible and resistant wheat cultivars (Triticum aestivum L. var Betta and Betta-Dn1 respectively) were carried out to establish the level of ultrastructural damage caused by this aphid and the possible limitation of damage induced which could be ascribed to the resistance gene Dn1 over the susceptible cultivar. Ultrastructurally, Betta-Dn1 sustained less damage to the vascular tissue as well as to the mesophyll during the experimental period. Both inter- and intracellular probes resulted in considerable saliva deposition as the aphids probed for suitable feeding sites. Salivary tracks were observed between and within mesophyll, bundle sheath cells as well as the vascular tissue, including the xylem. Disruption of organelles and cytoplasm resulted from cell probing and sheath deposition. Cell and organelle damage was more evident in the non-resistant Betta cultivar. The aphids probed for and fed from thin-walled sieve tubes preferentially. Few thick-walled sieve tubes showed evidence of either aphid probing or feeding-related damage. Saliva was deposited when the aphids probed inter- and intracellularly for feeding sites. The aphids appeared preferentially to probe for and feed from thin-walled sieve tubes, as few thick-walled sieve tubes showed evidence of damage. Vessels, apparently probed for water, contained watery saliva that encased the secondary walls and sealed pit membranes between probed vessels and xylem parenchyma. The xylem probed by the RWA was rendered non-functional, probably contributing to symptoms of leaf roll, chlorosis and necrosis, which were observed within two weeks of infestation in the susceptible Betta cultivar. This damage was limited in the resistant Betta-Dn1 cultivar during the same time frame

How sociable? An exploratory study of university brand visibility in social media

Social media has changed both the way in which organizations and their brands interact with their customers and the way in which business gets done. Brands are attempting to utilize social media to reach existing customers, gain new ones and build or maintain credibility and reputation. More importantly, brands need to measure their visibility in the most popular social media relative to that of competitors. This study describes a tool for collecting brand visibility information by looking at the visibility of various South African university brands and their relative positioning from a social media perspective. Correspondence analysis is then used to portray the various university brands in a multi-dimensional space so that they can be contrasted with each other in terms of their visibility in social media. The findings indicate that South African university brands are not distinctly positioned in social media and that none of them seems to currently have a concerted strategy for engaging its stakeholders in a particular social media. This means that there are both opportunities for those who manage these brands, and also threats to these institutions for taking a laissez fair attitude to social media in these times when social media are coming to dominate the Internet in particular and media in general

The ‘Galilean Style in Science’ and the Inconsistency of Linguistic Theorising

Chomsky’s principle of epistemological tolerance says that in theoretical linguistics contradictions between the data and the hypotheses may be temporarily tolerated in order to protect the explanatory power of the theory. The paper raises the following problem: What kinds of contradictions may be tolerated between the data and the hypotheses in theoretical linguistics? First a model of paraconsistent logic is introduced which differentiates between week and strong contradiction. As a second step, a case study is carried out which exemplifies that the principle of epistemological tolerance may be interpreted as the tolerance of week contradiction. The third step of the argumentation focuses on another case study which exemplifies that the principle of epistemological tolerance must not be interpreted as the tolerance of strong contradiction. The reason for the latter insight is the unreliability and the uncertainty of introspective data. From this finding the author draws the conclusion that it is the integration of different data types that may lead to the improvement of current theoretical linguistics and that the integration of different data types requires a novel methodology which, for the time being, is not available

The ‘Galilean Style in Science’ and the Inconsistency of Linguistic Theorising

Chomsky’s principle of epistemological tolerance says that in theoretical linguistics contradictions between the data and the hypotheses may be temporarily tolerated in order to protect the explanatory power of the theory. The paper raises the following problem: What kinds of contradictions may be tolerated between the data and the hypotheses in theoretical linguistics? First a model of paraconsistent logic is introduced which differentiates between week and strong contradiction. As a second step, a case study is carried out which exemplifies that the principle of epistemological tolerance may be interpreted as the tolerance of week contradiction. The third step of the argumentation focuses on another case study which exemplifies that the principle of epistemological tolerance must not be interpreted as the tolerance of strong contradiction. The reason for the latter insight is the unreliability and the uncertainty of introspective data. From this finding the author draws the conclusion that it is the integration of different data types that may lead to the improvement of current theoretical linguistics and that the integration of different data types requires a novel methodology which, for the time being, is not available

Vulvar cancer is not a disease of the elderly: Treatment and outcome at a tertiary referral centre in South Africa

Background. An increase in vulvar cancer in young women is attributed to infection with oncogenic human papillomavirus (HPV). South Africa (SA) has a high prevalence of HPV, and it was therefore hypothesised that women with vulvar cancer here would be younger than in high-income countries (HICs).Objective. To describe age, cancer stage, treatment and outcome of patients with vulvar cancer at a tertiary referral centre in SA.Methods. In a retrospective observational study, patient records of women diagnosed with vulvar cancer between 2001 and 2014 were reviewed and demographic and surgical details captured. Histology results of vulvar biopsies and resected specimens were checked for HPV changes, koilocytes and usual-type vulval intraepithelial neoplasia. Patients were restaged using the International Federation of Gynecology and Obstetrics (FIGO) 2009 staging system to allow for comparison of outcomes. Five-year disease-specific survival probability curves were generated using Kaplan-Meier analysis.Results. The mean age of the 180 patients in the study was 52.5 years. Those who had documented HPV changes on histological specimens had a mean age of 50.4 years. More than 50% of the patients had advanced-stage disease, and 62.7% were treated with primary surgery. Five-year disease-specific survival probabilities were similar to those reported in the literature.Conclusions. Vulvar cancer should not be regarded as a disease of the elderly in SA, as women with vulvar cancer are 10 - 15 years younger than in HICs. A large proportion of patients present with advanced-stage disease. Health professionals should be alert to vulvar lesions, especially in women with abnormal Pap smears, to reduce the morbidity and mortality of this disease.