1,130 research outputs found
Disordered minerals and disease of soft tissue and bones in chronic kidney disease
This article briefly reviews the mineral and bone disorder (MBD) found in patients with chronic kidney disease (CKD) and should provide a useful summary for trainees in nephrology and internal medicine. The storage of minerals is one of the principal roles of our bones, which are alive and are constantly being remodelled under the influence of vitamin D and parathyroid hormone (PTH), aided and abetted by calcium and phosphates. This occurs in a controlled fashion in healthy individuals. In patients with CKD, this control is lost and either an exaggerated, ineffectual remodelling takes place, resulting in the removal (in the case of high-turnover bone disease) or inadequate (in low-turnover bone disease) deposition of minerals. Vascular (and other soft tissue) calcification accompanies MBD, with phosphate and calcium playing major roles in the pathogenesis of the condition.
The development of MBD is insidious and evident by changes in blood PTH, calcium and phosphate levels seen as early as stage 3 CKD. Vascular calcification may also be observed at this early stage. Various reports have demonstrated associations between these abnormal blood levels and morbidity and mortality; however, randomised controlled studies are lacking that show definite proof of cause and effect.
In resource-limited countries, the control of PTH is restricted to the use of basic, inexpensive medicines, and patients with CKD can have inadequate means to afford blood tests. The use of vitamin D must be balanced between the use of natural vitamin D (a relatively cheap option) and active vitamin D. The cost of intravenous vitamin D analogues can be prohibitive. The more expensive phosphate binders (mostly non-calcium containing) too are unaffordable for most African patients. The surgical expertise to perform parathyroidectomies is limited to only certain major centres throughout the continent
Smallpox In Rhodesia And The Use Of The Electron Microscope In The Diagnosis Of This And Other Diseases
A CAJM article on the prevalence of smallpox in Zimbabwe (ex-Rhodesia) and the use of Electron Microscope in its diagnosis.This paper reports the laboratory findings in these cases of smallpox to indicate (1) the availability of such a medical service in Rhodesia to counter smallpox; (2) that rapid reporting can be achieved after receipt in the laboratory of the specimen; (3) that rapid positive alternative some days to reach the laboratory.
One technique used in the diagnosis of smallpox is electron-microscopy for virus particles, and some examples of the general usefulness of this technique in medical and veterinary diagnosis in Rhodesia are included in this report
The Fermat-Torricelli problem in normed planes and spaces
We investigate the Fermat-Torricelli problem in d-dimensional real normed
spaces or Minkowski spaces, mainly for d=2. Our approach is to study the
Fermat-Torricelli locus in a geometric way. We present many new results, as
well as give an exposition of known results that are scattered in various
sources, with proofs for some of them. Together, these results can be
considered to be a minitheory of the Fermat-Torricelli problem in Minkowski
spaces and especially in Minkowski planes. This demonstrates that substantial
results about locational problems valid for all norms can be found using a
geometric approach
Predicting the Date of Bud Burst in Grapevines
It was possible to forecast the date of bud burst under South African winter temperatures (Region III) using the Pouget-formulae and principles, and to establish a scale of bud burst for cultivars grown in South Africa. The sum of daily temperature effects was higher under the warmer South African conditions which resulted in changes in the formulae for determining the daily effect of temperature and the cultivar coefficient on the bud burst date. Highly significant linear relationships were, however, obtained and it was possible to predict the date of bud burst fairly accurately
Microbial Community Response to Various Degrees of Pasture Soil Disturbance
Commercial dairy farming from planted pasture is commonly practised in the southern Cape region of South Africa. These pastures are established by various methods ranging in degree of disturbance from no-tillage to conventional tillage. Different establishment methods may alter the below-ground ecosystem, and depending on the degree of disturbance, lead to changes in microbial biodiversity and soil health. Disturbance of pasture soil may play an important role in regulating soil microbial community structure. The aim of this study was to investigate changes in soil microbial community-level physiological profiles of kikuyu (Pennisetum clandestinum) pastures reinforced with annual ryegrass (Lolium multiflorum) by various degrees of soil disturbance
An Investigation Of The Effects Of Inoculated And Intralymphatic Vaccinia Virus On Primary And Secondary Deposits Of Malignant Melanoma
A CAJM investigation of the Effects of Inoculated and Intralymphatic Vaccinia Virus on Primary and Secondary Deposits of Malignant Melanoma.The six patients included in this investigation were selected on the basis of histologically-proven malignant melanomas of the lower extremity, with either local intradermal metastases or regional lymph node involvement. If unvaccinated in the previous five years, vaccination was performed at least 14 days before using the virus therapeutically.
Vaccinia virus was prepared from stock vacccine obtained from the South African Institute for Medical Research. Virus was inoculated on the Chorio-allantoic membrane of 12 day embryonated hens’ eggs in which growth was confluent on the third day. Virus was extracted in buffered saline, cleared and tested for sterility. The titre of the undiluted material was 107 pock forming units per ml. This was used at a dilution of 1:50 for both the superficial and deep lesions
LOOKING INSIDE VOTIVE CREATURES: COMPUTED TOMOGRAPHY (CT) SCANNING OF ANCIENT EGYPTIAN MUMMIFIED ANIMALS IN IZIKO MUSEUMS OF SOUTH AFRICA: A PRELIMINARY REPORT
The ancient Egyptians mummified many more animals than humans.
The study of ancient Egyptian animal mummies is varied and
extensive. Currently new methodologies and modern technology are
being used to unlock the secrets of animal mummies. Recently five
animal mummies housed in the Egyptian collection of Iziko
Museums of South Africa in Cape Town were scanned using a state
of the art computed tomography (CT) scanner at Stellenbosch
University. Preliminary results revealed two complete bird skeletons,
a claw, a fake and the partial skeleton of what appears to be a cat
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