13 research outputs found
Seasonal variation in serum ascorbic acid and serum lipid composition of free-living baboons (Papio ursinus)
Two surveys were conducted in the Kruger National Park in which 205 baboons were captured. The first survey was done during late summer and the second during late winter. Serum ascorbic acid, serum cholesterol and serum phospholipids were determined. Baboons of both sexes and various ages were captured. This work was undertaken to establish serum ascorbic acid, serum cholesterol and serum phospholipid values for baboons under free-living conditions. A seasonal variation was found, and the serum ascorbic acid serum cholesterol and serum phospholipid values were significantly higher during winter than during summer.S. Afr. Med. J., 48, 1700 (1974
Using phytoplankton diversity to determine wetland resilience, one year after a vegetable oil spill
A 250 t sunflower oil spill in the Con Joubert Bird Sanctuary Wetland, South Africa, was the largest
global sunflower oil spill in a freshwater wetland to date. Since there was insufficient historical data for the Con
Joubert Bird Sanctuary Wetland prior to the spill, variations in phytoplankton assemblages were used to indicate
wetland resilience in relationship with water quality variables. From this study, it was evident that the phytoplankton
biodiversity was a more reliable indicator of wetland resilience than vegetable oil concentrations
measured in the water column. Vegetable oil concentrations measured in the water column varied both spatially
and temporally and can possibly be linked to the passive movement of drifting oil in the water column caused by
wind action and temperature changes. While we were unable to pinpoint the exact mechanisms behind the
increase in phytoplankton biodiversity, the response was probably driven by the degradation of the oil by
natural microbial consortiums in the wetland or a possible increase in phytoplankton grazers. Certain phytoplankton
genera were found to be tolerant to the adverse effects of the oil spill. These genera include
Oedogonium, Cyclotella, Spirogyra, a n d Planktothrix. In general, the univariate and multivariate statistical
analysis showed a low diversity and richness at sites 1, 2 and 3 during the initial sampling surveys when compared
to the remaining sites. However, the phytoplankton diversity and richness subsequently increased at all sampling
sites from the second sampling survey, implying that there was a shift in phytoplankton biodiversity to a more
stable state.National
Research Foundation of South Africahttp://link.springer.com/journal/112702015-07-31hb201
Effects of vegetable oil pollution on aquatic macroinvertebrate assemblage in a freshwater wetland and its use as a remediation tool
The occurrence, as well as the environmental
fate and impact, of vegetable oil spills in freshwater
wetlands have until now been unreported. Thus, the
largest global vegetable oil spillage in a freshwater
wetland, which occurred at the Con Joubert Bird
Sanctuary wetland in 2007, presented an ideal opportunity
to evaluate these impacts. Five post-spill sampling
sites were selected within the wetland from which a
variety of abiotic and biotic samples were collected bimonthly
over a period of 12 months. Abiotic variables
included the sediment and water column oil concentrations,
total nitrogen, total phosphorous, biochemical oxygen demand (BOD), silica, chlorophyll a, as well
as in situ measurements of pH, electrical conductivity,
and dissolved oxygen. Aquatic macroinvertebrates were
chosen as biotic indicators in the study field due to their
wide applicability as water quality indicators and were
thus collected at each site. Spatial and temporal changes
in total nitrogen, total phosphorous, and chlorophyll
a concentrations as well as changes in pH were observed.
The oil spillage also resulted in an increase in
tolerant macroinvertebrate taxa, mainly Chironomidae
and Psychodidae, at the sites closest to the source of
the spillage. These two taxa, and to a lesser extent,
Syrphidae, were identified as potentially useful indicators
to determine the extent of vegetable oil contamination
within a freshwater wetland. Furthermore, monitoring of
these indicator taxa can be a useful management tool to
determine the recovery of freshwater wetlands after vegetable
oil spills. In the study, a static battery of bioassays of
different biotic trophic levels was also employed to determine
the adverse effects of the spilled vegetable oil on
the biotic environment. It was evident from the result of
the static battery of bioassay that adverse effects of the
sunflower oil differ between trophic levels. The latter was
in relationship with the data obtained from the field
macroinvertebrate study, indicating that certain macroinvertebrate
families were more tolerant to the adverse
effects of sunflower oil than other families.http://link.springer.com/journal/11270hb2014mn201
An assessment of mercury contamination and the relationship between environmental variables and mercury concentrations in a seasonal wetland
A study was undertaken to assess the extent
of mercury contamination in the water and sediment in
a seasonal wetland, as well as to determine the relationship
between environmental parameters and the
distribution of the mercury contamination. Water and
sediment samples were collected and analysed for
methylmercury, inorganic mercury and other physical
and chemical variables. One-way analysis of variance
and homogeneity of variance were performed, and
linear regression analysis was used to determine correlations
between mercury and other environmental
variables. The highest mercury concentrations were
recorded at the sites located closest to the industrial
complex. Methylmercury concentrations in the water
and sediment were mostly higher during the low flow
season, while inorganic mercury concentrations in the
water and sediment were higher during the high flow
and low flow seasons, respectively. Chromium, manganese,
organic carbon and fine sediment particles
were found to have significantly positive correlations
with mercury concentrations in water and sediment. It
was also found that the mercury concentrations decreased
within a relatively short distance from the sites
closer to the industrial complex to the sites further
downstreamSouth
African Synthetic Oil Limited (SASOL)http://link.springer.com/journal/11270#AboutSectionhttp://link.springer.com/article/10.1007%2Fs11270-013-1547-8DOI 10.1007/s11270-013-1547-
Long-term intravenous treatment of Pompe disease with recombinant human alpha-glucosidase from milk.
Contains fulltext :
57497.pdf (publisher's version ) (Open Access)OBJECTIVE: Recent reports warn that the worldwide cell culture capacity is insufficient to fulfill the increasing demand for human protein drugs. Production in milk of transgenic animals is an attractive alternative. Kilogram quantities of product per year can be obtained at relatively low costs, even in small animals such as rabbits. We tested the long-term safety and efficacy of recombinant human -glucosidase (rhAGLU) from rabbit milk for the treatment of the lysosomal storage disorder Pompe disease. The disease occurs with an estimated frequency of 1 in 40,000 and is designated as orphan disease. The classic infantile form leads to death at a median age of 6 to 8 months and is diagnosed by absence of alpha-glucosidase activity and presence of fully deleterious mutations in the alpha-glucosidase gene. Cardiac hypertrophy is characteristically present. Loss of muscle strength prevents infants from achieving developmental milestones such as sitting, standing, and walking. Milder forms of the disease are associated with less severe mutations and partial deficiency of alpha-glucosidase. METHODS: In the beginning of 1999, 4 critically ill patients with infantile Pompe disease (2.5-8 months of age) were enrolled in a single-center open-label study and treated intravenously with rhAGLU in a dose of 15 to 40 mg/kg/week. RESULTS: Genotypes of patients were consistent with the most severe form of Pompe disease. Additional molecular analysis failed to detect processed forms of alpha-glucosidase (95, 76, and 70 kDa) in 3 of the 4 patients and revealed only a trace amount of the 95-kDa biosynthetic intermediate form in the fourth (patient 1). With the more sensitive detection method, 35S-methionine incorporation, we could detect low-level synthesis of -glucosidase in 3 of the 4 patients (patients 1, 2, and 4) with some posttranslation modification from 110 kDa to 95 kDa in 1 of them (patient 1). One patient (patient 3) remained totally deficient with both detection methods (negative for cross-reactive immunologic material [CRIM negative]). The alpha-glucosidase activity in skeletal muscle and fibroblasts of all 4 patients was below the lower limit of detection (3 years of treatment. Anti-rhAGLU immunoglobulin G titers initially increased during the first 20 to 48 weeks of therapy but declined thereafter. There was no consistent difference in antibody formation comparing CRIM-negative with CRIM-positive patients. Muscle alpha-glucosidase activity increased from 42 degrees C, unstable blood pressure, and coma. The respiratory course of patient 1 remained uneventful. The 2 older patients, who both were hypercapnic (partial pressure of carbon dioxide: 10.6 and 9.8 kPa; normal range: 4.5-6.8 kPa) at start of treatment, became ventilator dependent before the first infusion (patient 2) and after 10 weeks of therapy (patient 4). Patient 4 was gradually weaned from the ventilator after 1 year of high-dose treatment and was eventually completely ventilator-free for 5 days, but this situation could not be maintained. Currently, both patients are completely ventilator dependent. The most remarkable progress in motor function was seen in the younger patients (patients 1 and 3). They achieved motor milestones that are unmet in infantile Pompe disease. Patient 1 learned to crawl (12 months), walk (16 months), squat (18 months), and climb stairs (22 months), and patient 3 learned to sit unsupported. The Alberta Infant Motor Scale score for patients 2, 3, and 4 remained far below p5. Patient 1 followed the p5 of normal. CONCLUSION: Our study shows that a safe and effective medicine can be produced in the milk of mammals and encourages additional development of enzyme replacement therapy for the several forms of Pompe disease. Restoration of skeletal muscle function and prevention of pulmonary insufficiency require dosing in the range of 20 to 40 mg/kg/week. The effect depends on residual muscle function at the start of treatment. Early start of treatment is required
Debating some past and present research frameworks and methodologies in history on places and their peoples in South Africa
Histories regarding places and their peoples in South Africa can be traced to the early days of History being practised as an academic discipline. However, practising this form of history under (and outside) the flag of regional history was formalised only in the mid seventies, while informalised research practices in the field continued as methods complementing various schools of thought. Narrowly perceived local histories were considered as inclusive of the formalised and informalised regional history practices as knowledge contributing towards a broader understanding of a (geographically defined/ politically demarcated) region. Of interest is not only the historiography in this field (of which a few pointers are shared in this discussion) but some of the frameworks and methods to research and to record regional histories that have been used in the past. Equally of interest are the ways in which these frameworks and methods are still applied and thought of as dynamic and progressive to assist the historian to progress towards producing and packaging research as part of a comprehensive, all inclusive approach in creating knowledge as regional history studies. In South Africa, an extensive debate on how regional history studies should be broadly defined and understood when undertaking research, still falls short. This is due to the variety, diversity and complexity of knowledge contributing to the pool of information that should be packaged as regional history studies. To contibute towards a framework of understanding and packaging knowledge in this field of meaning to regional history studies, the reader is further exposed to an extended structure of perhaps understanding and doing research in this field: a field that has always been regarded as having the potential to be both integrative and multidisciplinary by nature. Yet its integrative analytical abilities also rest on the outcome of narrow-defined histories done on spaces and places before it is possible to embark on bigger research analyses in, for example, the spirit of modern social history applications to regional history studies. This discussion on ways to understand the limited past and present of regional studies (historiographically and methodologically) in South Africa is offered to encourage further debate.10.1080/17532523.2013.857095http://dx.doi.org/10.1080/17532523.2013.85709