1834 research outputs found
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Isolation of bioactive compounds and in vitro studies on pentanisia prunelloides (klotzsch ex eckl. & zeyh.) walp. used in the eastern Free State for the management of diabetes mellitus
No full textThe pravelence of diabetes mellitus is increasing and it is one of the major health problems affecting the world. The challenges with synthetic drugs used in the treatment of hyperglycemia such as acarbose and miglitol include abdominal discomfort, bloating and diarrhoea. The present study isolated and evaluated the active antidiabetic constituents from the roots of Pentanisia prunelloides (Rubiaceae) from the eastern Free State Province of South Africa using in vitro models. The antidiabetic potential of the water, ethanol, aqueous-ethanol and hexane root extracts of P. prunelloides was investigated against the specific activities of α-amylase, α-glucosidase, sucrase and maltase. Furthermore, the antioxidant activity of the extracts was determined using iron chelation, 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radical scavenging assays. For the fractions and the isolated compounds, only α-amylase and α-glucosidase assays were used. Fractionation of the ethanol extract was done by vacuum liquid chromatography (VLC), fractions were combined according to thin layer chromatography (TLC) profiles, and further purification of semi-pure compounds was achieved using preparative thin layer chromatography (pTLC) to obtain pure compounds. Isolated compounds were characterised using nuclear magnetic resonance (NMR) (1D and 2D data) and mass spectroscopy (MS). The ethanol extract displayed significantly higher (p < 0.05) inhibition of α-amylase (18.51 μg/mL), hexane (18.08 μg/mL) and ethanol (19.73 μg/mL) extract exhibited strongest inhibition of α-glucosidase. Water extract demonstrated strong inhibition of sucrase (3.85 μg/mL), and aqueous-ethanol extract (26.03 μg/mL) on maltase. Kinetic studies showed that the mode of inhibition of α-amylase and α-glucosidase by ethanol extract was mixed non-competitive and non-competitive respectively. Water and ethanol extract displayed higher DPPH (75.42 μg/mL) and (77.06 μg/mL) scavenging abilities than other extracts but not higher than gallic acid. Hexane extract demonstrated significantly higher (p < 0.05) superoxide (0.33 μg/mL) and hydroxyl radical (0.51 μg/mL) scavenging abilities while aqueous-ethanol exhibited the strongest iron chelation activity 4.24 μg/mL. Phytochemical analysis of the extract revealed the presence of tannins, terpenoids, alkaloids, saponins, flavonoids and cardiac glycosides. Quantification of phytochemicals revealed total flavonoids of 15.40 mg quercetin equivalent (QE)/g in hexane extract which was not significant (p > 0.05) and from water it was 14.70 mg QE/g. The highest tannin concentration of 45.60 mg gallic acid equivalent (GAE)/g was from aqueous-ethanol which was significantly higher than other extracts (p < 0.05). Total phenol from water and aqueous extracts was 0.07 mg GAE/g; alkaloids and saponins were found to be low in the roots of P. prunelloides, at 0.6 and 13.9% respectively. Of the 21 fractions obtained, acetylated fraction displayed significantly higher (p < 0.05) inhibition of α-amylase 48.06 μg/mL while fraction PP-I-101835BII exhibited strongest inhibition of α-glucosidase (19.53 μg/mL). Three compounds were isolated, two sucrose (acetylated and non-acetylated) and tormentic acid. Tormentic acid inhibited α-amylase and α-glucosidase at 70.45 μg/mL and 28.21 μg/mL respectively. Kinetic analysis revealed that tormentic acid inhibited α-amylase in un-competitive manner and α-glucosidase competitively. The ethanol extract and the isolated tormentic acid exhibited best inhibitory activity on the two enzymes studied, and the presence of phytochemicals in the roots of P. prunelloides in this study may be suggested to have contributed greatly to the biological activities of the plant. Tormentic acid appears to be a potential anti-diabetic drug thus supporting usage of the root extract of P. prunelloides in the management and treatment of diabetes mellitus in the eastern Free State Province.National Research Foundatio
Two new species of Achnanthidium Kützing (Bacillariophyceae) from Kolli Hills, Eastern Ghats, India
No full textTwo new freshwater species of Achnanthidium Kützing are described from Eastern Ghats Mountain
range of Peninsular India based on light and scanning electron microscopy observations. Achnanthidium initium
sp. nov. belongs to the group of Achnanthidium taxa that have terminal raphe fissures curved to opposite sides
of the valve. This taxon is characterized by distinctive fascia, raphe endings extending to the valve margin,
lineate distal raphe endings and 2–5 linear areola per striae. Achnanthidium linannulum sp. nov. belongs to the
group of Achnanthidium taxa with terminal raphe fissures curved to the same side of the valve. This species
is characterized by the presence of occluded areolae near the margin, striae orientation and the weakly bent
internal distal ends of the raphe. These new species are known only from their type locality, oligotrophic
Masilla Waterfalls from Kolli Hills, Eastern Ghats.South African National Research Foundation (NRF
Benthic algal communities of shallow reefs in the Eastern Cape: availability of abalone habitat
No full textMarine ranching has been identified as an alternative to traditional aquacultural rearing and growing organisms for consumption. In the Eastern Cape, abalone ranching is a new and experimental industry. The aims of the research were to: first develop a GIS model to assist management in site selection for abalone seeding; and secondly to develop and standardize the sampling methodology in order to ground truth the sites, and assist in the monitoring and habitat identification of abalone. The GIS model developed in Chapter 3 was created using an unsupervised classification and fuzzy logic approach. Both vector and raster datasets were utilized to represent 7 different layers. Predominantly satellite imagery was used to classify the different substrate groups according to pixel colour signatures. The basic process was to apply a fuzzy rule set (membership) to rasters which gave an output raster (Fuzzification). The membership output rasters were overlaid which creates a single model output. It was found that model accuracy increased significantly as more layers were overlaid, due to the high variability within each of the individual layers. Model ground-truthing showed a strong and significant correlation (r2 = 0.91; p < 0.001) between the model outputs and actual site suitability based on in situ evaluation. Chapter 4 describes the investigation towards the optimal sampling methods for abalone ranching habitat assessments. Both destructive sampling methods and imagery methods were considered as methods of data collection. The study also evaluated whether quadrat and transects were going to be suitable methods to assess sites, and what size or length respectively they should be to collect the appropriate data. Transect length showed great variation according to the factor assessed. A transect of 15 metres was found to be optimal. Abalone counts showed no significant (p = 0.1) change in the Coefficent of Variance (CV) for transect lengths greater than 15m, and had a mean of 0.2 abalone per metre. Quadrat size showed a significant difference in functional group richness between quadrat sizes of 0.0625m2, and 0.25m2 but no difference between 0.25m2 and 1m2 quadrats for both scape and photographic quadrats. It was also found that between 5 and 10 replicates (p = 0.08) represents the functional groups appropriately using quadrats and that a 0.25m2 quadrat is most suitable for sampling. Chapter 5 describes the benthic community structure of Cape Recife shallow water reefs. Using the standardized methodology previously mentioned, 45 sites were assessed to identify the community structure. These sites were grouped into 5 different groups influenced by depth and substrate, as well as functional group composition according to a Wards classification. The community structure showed that depth and substrate play a significant role (p < 0.05) in the community type. There is also a significant relationship (p < 0.05) between complexity, rugosity, abalone presence and substrate. During this study the basic protocols for site selection and benthic community monitoring have been developed to support the abalone ranching initiative in the Cape Recife area. It has also provided a baseline of the benthic community in the ranching concession area which will be used as a benchmark for future monitoring efforts. The site selection, sampling, and monitoring methods developed during the course of this work have now been rolled out as Standard Operating Procedures for the ranching programme in this area.National Research Foundatio
Characterization of a glycated gelatin model to explore the therapeutic properties of macrofungi in diabetic wound healing: an in vitro study
No full textDiabetic wounds frequently undergo impaired and prolonged wound healing due to a multitude of factors including hypoxia, impaired angiogenesis, hyperglycaemia, formation of ROS and AGEs, and infection - all of which may lead to cellular dysfunction. To date, however, treatment options for individuals suffering from impaired diabetic wound healing are limited, non-specific, and generally unsuccessful. The search for new and effective treatment strategies is severely hampered by the availability of adequately characterized screening models which comprehensively mimic the complexity of the diabetic wound healing process. In order to explore natural products as potential therapeutics to treat diabetic wounds and to encourage more research on this topic, this study sought out to develop and characterize a more convenient and cost effective in vitro screening assay which mimics the effects of protein glycation on the healing process of diabetic wounds. As proof of principal, this model was subsequently used to screen the potential of five wild mushroom species (P. tinctorius, R. capensis, B. badius, P. ostreatus and G. lucidum) as suitable diabetic wound healing therapies. The glycated gelatin model developed during this study was found to suitably mimic the diabetic state as it successfully simulated the major cellular dysfunctions in macrophages (NO production, phagocytosis, macrophage polarization, NF-ĸB translocation and COX-2 expression) and fibroblasts (proliferation and migration) documented during diabetic wound healing. Together these findings provide confidence that the model may serve as a valuable tool to study the poorly understood mechanisms which characterize cellular dysfunction in response to AGE accumulation and also to aid the identification of novel therapeutic agents to treat this pathology. Screening a number of mushroom extracts revealed that the ethanol extracts of R. capensis and P. ostreatus had the greatest potential for attenuating chronic inflammation due to their ability to promote macrophage phagocytosis, increased M2 activation (R. capensis) and decreased M1 activation (P. ostreatus) as well as reduced COX-2 expression while the water extract of G. lucidum proved to be the most promising candidate for stimulating fibroplasia as it was the most successful at promoting both fibroblast proliferation and migration. Different mushroom species were thus shown to promote different stages of the wound healing process providing sufficient evidence to support further studies related to the use of macrofungi as therapeutic agents in the search for more cost-effective and efficient treatment strategies for impaired diabetic wound healing.National Research Foundatio
Ecology of key cerithioidean gastropods in the mangroves of the iSimangaliso Wetland Park, KwaZulu-Natal South Africa
No full textGastropods are one of the most diverse species groups in mangrove habitats, however, many of their specific roles in relation to ecological patterns and processes are currently largely unknown. The overall aim of this research project was to provide basic ecological information for key gastropod species from subtropical mangroves within a protected area. South African mangroves cover relatively small areas and are restricted to estuaries, these habitats therefore present unique opportunities and challenges to the species that occur in them. Three gastropod species, Terebralia palustris, Cerithidea decollata, and Melanoides tuberculata, all occur at their natural southernmost range limit within South Africa and were selected based on their prominence and occurrence in mangrove habitats of the iSimangaliso Wetland Park, a UNESCO World Heritage Site. Trophic linkages and resource partitioning, resource utilization rates, and ecological resilience were investigated respectively using: 1) a stable isotope (δ15N and δ13C) approach; 2) an experimental approach to quantify feeding dynamics (ingestion rate, consumption/digestion efficiency and grazing impact); and 3) a mixed-effects modelling approach to relate population responses to environmental variables. The diet of T. palustris was seasonally variable and a number of sources were incorporated by different sized snails, but their grazing impact on microphytobenthos was not significant. The results also indicated an ontogenetic shift in the dietary niche for T. palustris through robust partitioning of resources between different size classes. The diets of C. decollata and M. tuberculata were dominated by different primary resources as a function of where they occurred in the mangroves. Melanoides tuberculata consumed a wide variety of primary resources, a typical trait of an opportunistic generalist species. The ingestion rate of M. tuberculata was not dependent on the availability of microphytobenthos, and was highest when conditions were oligotrophic. The resilience of C. decollata was related to the tree-climbing behaviour of this species and its occurrence was best explained by sediment conductivity. These responses were considered in conjunction to what has previously been reported on the resilience of the mangrove trees. The results of this research project have provided new basic ecological information for all three gastropod species in this data-deficient subtropical region. This information can potentially be used in comparative studies for these species in other regions or in broader scale ecological studies. Terebralia palustris has recently experienced a range contraction along the South African coastline. This research project has shown that the diet of this species is highly variable and that food limitation and competition for resources should be considered as potential drivers of the local decline. Cerithidea decollata has in contrast expanded its distributional range in this region. This research project has shown that this species has a generalist diet and exhibits traits in relation to tolerance that are expected to have facilitated its expansion into temperate saltmarsh habitats that occur in dynamic estuaries. Melanoides tuberculata is a globally invasive species, and as South African populations are within its native range, ecological information from this region is valuable as it can be used to investigate the potential ecological effects following introduction into new habitats beyond the native range. Biological drivers have a significant impact on mangrove ecosystem functioning, particularly in relation to recycling and the retention of organic carbon generated through primary productivity. Understanding the ecological linkages that maintain ecological functioning and stability is therefore an important step towards conserving and sustainably managing threatened ecosystems such as mangrove forests.National Research Foundatio
Healthcare workers’ behaviours and personal determinants affecting sexual and reproductive healthcare service provision to adolescents in South Africa
No full texthttps://cris.maastrichtuniversity.nl/portal/en/publications/healthcare-workers-behaviours-and-personal-determinants-affecting-sexual-and-reproductive-healthcare-service-provision-to-adolescents-in-south-africa(2d78e74d-6035-4fd4-92e7-f16b385fbd86).htmlNational Research Foundatio
Finances & Audits
No full textThe Grants Management and Systems Administration (GMSA) Directorate hosted its 8th annual Research Administrators Workshop (RAW) from 9 to 11 October 2017 in the Western Cape. The workshop aimed to bring together key stakeholders from universities and science councils across South Africa, including international delegates, to share experiences and best practices in research administration and management
Factors affecting participation in sport and recreation of students staying in residences at the University of KwaZulu-Natal.
No full textAlmost all the institutions of higher learning across the globe offers sport and recreation opportunities to its students and staff. These programmes and services are offered to serve several purposes of which at the summit of them all is to improve social cohesion and physical fitness of the students and staff members. The challenge faced by most tertiary institutions is that services and infrastructure provided are either over-utilised or underutilised and there appears to be unknown factors precipitating the situation. It is therefore important that the motives and constraints to sport and recreation participation be discovered in an effort to help direct future strategic plans and correct present and past mistakes. The primary aim of the present study is to ascertain the factors that affect local and international student’s participation in sport and recreation, with the intention of providing pertinent information that the University of KwaZulu-Natal Sport Administration Office can utilize in imminent strategic plans for campus based sport and recreation delivery. A descriptive research design was utilised and a questionnaire was designed to investigate the views and perceptions of students (n=199) staying at the University of KwaZulu-Natal residences. The Median (M) and Interquartile Range (IQR) was used as a summary statistic. The non-parametric two-sample Wilcoxon rank-sum (Mann-Whitney) test was used to compare sub-groups. Intrapersonal and interpersonal factors prevents participation, more specifically time and lack of partners. Justifications for participation in sport and recreation were achievement/status, energy release and fun. Findings further reveal differences based on gender and age highlight the views of students on unequal treatment of various sport and recreation codes on campus. The study findings further advance knowledge on constraints and motives affecting sport and recreation participation among university students, revealing information for policymakers to consider when designing programmes for student services on campus.National Research Foundatio
A profile of patients presenting with spinal pain at Mahalapye and Shoshong World Spine Care clinics in Botswana
No full textA profile of patients presenting with spinal pain at Mahalapye and Shoshong World
Spine Care clinics in Botswana
Background: Spinal pain such as low back and neck pain, are common and can cause
severe long term pain which results in a major burden on individuals and health care
systems (Woolf and Pfledger, 2003; Hondras et al., 2015a). Low-income countries often
have few resources for adequately addressing musculoskeletal (MSK) pain (Louw et al.,
2007). Thus, World Spine Care (WSC), a non-governmental organization, opened two clinics
in Botswana to help improve spinal health care by providing access to MSK specialists
(Haldeman et al., 2015). These clinics have been functional since 2012, and to date the
profile of patients attending these clinics has not been investigated. Studies on patients
attending chiropractic clinics have been carried out internationally (Hartvigsen et al., 2002;
Giles et al., 2002; Coulter and Shekelle, 2005; Holt and Beck, 2005; Mootz et al., 2005;
Sorensen et al., 2006; Garner et al., 2007; Stevens, 2007; Rubinstein et al., 2008; Martinez
et al., 2009; Ailliet et al., 2010; Lischyna and Mior, 2012) and locally (Benjamin, 2007;
Jaman, 2007; Mohamed, 2007; Venketsamy, 2007; Higgs, 2009; McDonald, 2012; Hitge,
2014), and yet very little information exists on the patients presenting to clinics in the public
sector of Botswana. Demographic and disease profiles of patients vary by clinical setting,
from country to country, and within regions of the same country (Hoy et al., 2010a). Thus,
this study aimed to determine the demographic and disease profile of spinal pain patients
attending the WSC clinics in Mahalapye and Shoshong in Botswana.
Method: A retrospective, descriptive study design was used to extract data from the WSC
patient files at the Mahalapye and Shoshong WSC clinics from 1 November 2012 to 31
March 2016. The research proposal was approved by the Institutional Research Ethics
Committee (IREC); REC 53/16 (Appendix A), WSC (Appendix B) and Botswana MoH
(Appendix C). Patient files included had provided consent for their files to be used for
research purposes (Appendix F). Data recorded included demographic characteristics,
factors related to spinal pain, the presenting complaint and the presence of co-morbid
conditions. The data was analysed using Statistical Package for the Social Science (SPSS)
version 24.0. Descriptive statistics in the form of graphs and cross tabulations were used to
describe the demographic and disease profile of the spinal pain patients. Inferential statistics
like chi-square, Fischer’s exact test for categorical variables and Independent student’s t tests for numerical variables were used to determine differences between the two clinics. A
p-value of less than 0.05 was used to indicate statistical significance (Singh, 2016).
Results: The sample size was 65% (n=714). There was a female preponderance (75.2%,
n=537), a mean age of 50.6 years (±SD 16.13). Most patients were married (38%) and the
most common occupations were either farmers (18.2%, n=129) or unemployed (16.3%,
n=115). The majority of patients suffered from chronic (88%), idiopathic (59.5%), low back
pain (69.9%), followed by upper/mid back (19.1%), with the least visits occurring for neck
pain (8%). The most frequent diagnosis was joint dysfunction with associated soft tissue
disorders. The patients reported mild disability with moderate pain intensity and most
patients had not experienced previous spinal pain (60%). The patients did not report a
secondary area of MSK pain (28.6%) and 73.9% of patients presented with at least one comorbid
condition.
Patients attending the rural clinic were older on average (52.7 years, ±SD 16.92) than those
at the urban clinic (48.9 years, ±15.29) (p = 0.002). There were more women attending the
urban clinic when compared to the rural clinic (p = 0.009), with those attending the rural
clinic most often reporting a primary school level of education in contrast to those in the
urban clinic having most likely obtained a more than secondary school education (p <
0.001). More patients in the urban clinic had “other mechanical” e.g. joint dysfunction as an
aetiology for their spinal pain when compared to the rural clinic (p = 0.039). In terms of pain
duration, the rural clinic patients were more likely to present with acute and subacute pain
than at the urban clinic (p = 0.001). The rural clinic patients also reported more previous
episodes of spinal pain in contrast to those from the urban clinic (p <0.001).
Conclusion: The spinal pain patients attending the WSC clinics had many similarities to
spinal pain patients internationally and in SA, however unique differences were found
specifically when the urban and rural clinic patients were compared. The findings of this
study can assist WSC to provide more targeted healthcare at each clinic and within this
region.National Research Foundation (South Africa
A portable robotic rehabilitation system towards improving impaired function of the hand due to stroke
No full textBackground: Stroke is the leading cause of adult disability with 70 to 85% of initial strokes resulting in hemiparesis. Physical imparity as a result of stroke tends to be severe and majority of impairments are upper limb-related. Impairment is usually accompanied by long term functional loss which requires dedicated post-stroke rehabilitation to regain motor function. The incidence of stroke is increasing rapidly while there remains a shortage of therapists to provide sufficient rehabilitation. There is therefore a high demand for therapists to attend to the rising number of stroke survivors. Robot-aided therapy has emerged as a beneficial tool for providing continuous rehabilitation of the upper limb and is widely being implemented. With this technology, there is great potential to reduce the ill-effects brought about by the low therapist-patient ratio which has hindered sufficient rehabilitation and consequently the effective recovery of motor function among stroke survivors. Hypothesis: The use of a portable robotic rehabilitation system, as a complementary tool, in hand therapy, would promote continuous rehabilitation by encouraging repetition of task oriented exercises which would enhance motor function of an impaired hand. Task-oriented writing practice would potentially improve hand coordination and result in better accuracy while repetitive training would potentially increase hand motor strength. Objectives: 1.To design and manufacture a portable robotic rehabilitation system. 2. To test the performance and usability of the system. Methods: The system was manufactured and its performance tested in a pilot pre-clinical trial involving three participants. The system's ease of use was assessed using a standardised usability scale. Writing accuracy and hand motor strength were also assessed and the results analysed at the end of the study. Results: The average overall score of usability for the rehabilitation system was a few points higher than the average score. The users of the system also experienced increased motivation whilst performing the repetitive and task oriented exercises. There was an improvement in the completion time of the writing accuracy test and the tasks of the trace sample test. The variation in grip strength of the non-dominant hand during the rehabilitation period was small for each of the participants. Conclusion: The rehabilitation system motivated its users to repetitively perform rehabilitative training which may have improved writing accuracy.National Research Foundation (South Africa