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25th European Symposium on Calcified Tissues entitled 'Defining Typologies in Osteoporosis', Harrogate, April 25, 1997 : Fast and slow bone losers: Relevance to the management of osteoporosis
(1998) Hough, S.
A low bone mineral density (BMD) is presently regarded as the most important risk factor for the development of osteoporosis. BMD is a function of peak bone mass attained during growth and subsequent age-related bone loss. BMD can be measured accurately and precisely, although the rate of bone loss is more difficult to assess. When axial BMD was measured, the rate of bone loss was shown to increase by 2- to 4-fold at the menopause. Although this rate varies markedly between individuals, it is symmetrically distributed, which argues against the existence of a subpopulation of fast bone losers. Levels of biochemical markers of bone turnover (e.g. osteocalcin, bone specific alkaline phosphatase, deoxypyridinoline) also increase markedly at the menopause. and individuals with a high turnover tend to lose bone more rapidly. Moreover, since increased bone resorption also results in qualitative changes regardless of BMD, a high bone turnover constitutes an independent risk factor. Currently, large intraindividual variations (10 to 40%) in levels of biochemical markers and assay errors still limit our ability to correctly classify individual patients as fast or slow bone losers. The routine use of these markers as a screening tool to predict the risk of osteoporosis in individuals is of limited value, although their selective use in therapeutic decision-making is more promising.
3-Dimensional imaging of the pelviocaliceal system by computerized tomographic reconstruction
(1990) Heyns C.F.; Van Gelderen W.F.C.
Safe and efficient performance of percutaneous nephrolithotomy requires 3-dimensional visualization of the pelviocaliceal anatomy. However, currently available modalities offer only 2-dimensional images, from which the operator must mentally reconstruct a 3-dimensional picture of the pelviocaliceal configuration. We evaluated the feasibility of obtaining 3-dimensional images of the pelviocaliceal system with the aid of computerized tomographic reconstruction and present 3 illustrative cases.
5- and 6-glycosylation of transferrin in patients with Alzheimer's disease
(2004) Van Rensburg S.J.; Berman P.; Potocnik F.; MacGregor P.; Hon D.; De Villiers N.
Transferrin is a glycosylated metal-carrying serum protein. One of the biological functions of glycosylation is to regulate the life span of proteins, less glycosylation leading to a faster clearance of a protein from the circulation. In the case of transferrin, this would indirectly also influence iron homeostasis. Higher glycosylation has been demonstrated in patients with Parkinson's disease and rheumatoid arthritis. A genetic variant of transferrin, TfC2, occurs with increased frequency in patients with Alzheimer's disease (AD), rheumatoid arthritis, and other diseases associated with a free radical etiology. Investigations have so far not revealed the reason for the pro-oxidative qualities of TfC2. In this study the glycosylation of Tf in AD (TfC1 homozygotes and TfC1C2 heterozygotes) was compared with alcohol-induced dementia (AID) patients and nondemented, age-matched controls, using isoelectric focusing followed by blotting with anti-Tf antibodies. In TfC1 homozygotes a shift was found toward higher sialylation, but in TfC1C2 heterozygotes the 5- and 6-sialylated bands were less concentrated. The decreased sialalytion found for TfC1C2 heterozygotes, may indicate that the pro-oxidative TfC2 molecules are removed from the circulation at a faster rate than TfC1. This may be of benefit to AD patients having TfC2, but still does not explain why this Tf variant is pro-oxidative.
7-year follow up of intra-operative radiotherapy for early breast cancer in a developing country
(2012) Baatjes K.J.; Apffelstaedt J.P.
Scarce radiation resources and an often poor, rural population make single fraction, definitive intra-operative radiation (IORT) ideal for developing countries. From 2002 to 2005 IORT in breast conservation was administered utilizing existing infrastructure in an extremely resource-restricted environment. After tumor excision an applicator was introduced into the tumor bed. An existing Ir 192 after loader delivered a single fraction (21 Gy).Of thirty nine patients treated with 84 months follow-up, one patient suffered local, four regional and three systemic relapse. One patient died of disease, 2 of unrelated causes for a local control rate of 95% and a disease-specific survival of 95%. Cosmetic outcome was perceived excellent. IORT using existing after loaders and a low cost applicator greatly reduced health care resources. This extends breast conservation to indigent patients who cannot adhere to lengthy EBRT protocols. © 2012 Elsevier Ltd.
A 21-year-old patient with acute myeloid leukemia and bilateral pulmonary infiltrates
(2001) Theron J.; Ainslie G.; Schneider J.W.; Bates W.D.; Bolliger C.T.
[No abstract available]
A 5-year-old with abnormal hand and forearm
(2009) Du Plessis A.-M.; Andronikou S.; Offiah A.
[No abstract available]
A case of adult mesoblastic nephroma: Ultrastructure and discussion of histogenesis
(1990) Van Velden D.J.J.; Schneider J.W.; Allen F.J.
A benign fibromyomatous kidney tumor with deep seated tubular structures in a 20-year-old woman is reported as a case of adult mesoblastic nephroma. Ultrastructural exmination confirmed the fibromyomatous nature of the stroma and the tubules appeared to be an integral part of the tumor. The histogenetic relationship to congenital mesoblastic nephroma, Wilms tumor and other tumors is discussed. Radical nephrectomy was performed and the patient remained well 1 year later.
A challenging red eye clinical quiz
(2010) Smit D.
The pharmacist may see any of the following red eye cases and this clinical quiz is not only aimed at over-the-counter (OTC) medication, but also illustrates the importance of referring patients who do not respond to OTC medicines for (urgent) medical attention. The case studies are discussed in more detail after the initial case presentations. Read the case studies and decide whether the causes are infective, allergic, inflammatory, degenerative or neoplastic and decide what treatment you would prescribe for the customer and whether you would refer the patient for medical attention.
A community-based obstetric ultrasound service
(2004) Geerts L.; Theron A.M.; Grove D.; Theron G.B.; Odendaal H.J.
Objectives: To investigate the impact of an ultrasound dating service on obstetric services. Methods: A prospective trial with 3009 unselected women presenting for antenatal care at two Midwife Obstetric Units in a socioeconomically deprived urban area, South Africa. In the study unit, student ultrasonographers provided a basic ultrasound service. In the control unit, obstetric ultrasound was only available for specific indications. The main outcome measures were number of antenatal visits and referrals for fetal surveillance. Results: The two cohorts were comparable except for the number of primigravidas but stratified analysis according to parity did not affect the results. Ultrasonography did not alter pregnancy outcome but reduced the number of perceived preterm labors/ruptured membranes (12.0 vs. 16.7%, P<0.003), post-term deliveries (8.1 vs. 10.8%, P<0.04) and referrals for fetal surveillance [15.9 vs. 29.6%, P<0.000, RR 0.79 (0.71-0.88)]. Conclusions: This community-based basic ultrasound service significantly reduced referrals to a regional center for fetal surveillance and delivery. © 2003 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
A comparative analysis of embryo implantation potential in patients with severe teratozoospermia undergoing in-vitro fertilization with a high insemination concentration or intracytoplasmic sperm injection
(1996) Oehninger S.; Kruger T.F.; Simon T.; Jones D.; Mayer J.; Lanzendorf S.; Toner J.P.; Muasher S.J.
The objective of this study was to assess fertilization, implantation and pregnancy rates in infertile patients with severe teratozoospermia [P (poor prognosis) pattern sperm morphology assessed by strict criteria] treated by in-vitro fertilization (IVF) using a high insemination concentration (HIC), or by intracytoplasmic sperm injection (ICSI). This was a retrospective cohort study performed in an academic tertiary institution. The outcome of 115 consecutive ICSI cycles was compared to that of a similar number of cycles of IVF with HIC performed during a similar time frame and matched by woman's age and basal serum (cycle day 3) follicle stimulating hormone concentrations. The inclusion criteria were sperm morphology ≤4% normal forms (P pattern) and ≥1×106 total motile spermatozoa per ejaculate. The diploid fertilization rate in the HIC-IVF group was 86% and in the ICSI group 68% (P < 0.05). Importantly, an equal number of embryos was transferred to both groups of patients. The morphological quality of the embryos (proportion of transfers having superior morphology embryo scores) was significantly better in the ICSI group than in the patients receiving HIC-IVF. Although there was a clear trend for better implantation and pregnancy rates in the ICSI group, these differences were not statistically significant. We conclude that, although HIC-IVF resulted in a higher fertilization rate than ICSI in patients with severe teratozoospermia, ICSI produced a significantly higher proportion of morphologically superior embryos with a tendency towards a higher implantation potential. Therefore, teratozoospermic patients having adequate numbers of motile spermatozoa should be offered ICSI as an alternative to modified (HIC) IVF treatment.
A comparative study of the effects of cholesterol, beta-sitosterol, beta-sitosterol glucoside, dehydroepiandrosterone sulphate and melatonin on in vitro lipid peroxidation
(2000) Van Rensburg S.J.; Daniels W.M.U.; Van Zyl J.M.; Taljaard J.J.F.
The free radical scavenging abilities of the structurally related steroids beta-sitosterol, beta-sitosterol glucoside (plant sterols and sterolins), cholesterol, and dehydroepiandrosterone sulphate (DHEAS) were compared with melatonin (an efficient free radical scavenger) in an in vitro system which measures lipid peroxidation of platelet membranes in the presence of iron (Fe2+). Lipid peroxidation is a process whereby cellular membranes are damaged due to the oxidative deterioration of polyunsaturated lipids, which may lead to cell death and disease in living organisms. Substances such as vitamin E protect cellular membranes against oxidative damage due to their chemical structures. The steroids cholesterol, beta-sitosterol, beta-sitosterol glucoside and dehydroepiandrosterone (DHEA) are structurally related to each other. During aging, serum concentrations of DHEA, DHEAS and melatonin decrease, while the concentration of cholesterol tends to increase. The aim of the present study was to compare the role these substances play in lipid peroxidation over a wide concentration range. At concentrations lower than the free iron in the reaction mixture, all the steroids investigated decreased lipid peroxidation. At higher concentrations, cholesterol and beta-sitosterol increased lipid peroxidation, while DHEAS and melatonin continued to decrease lipid peroxidation.
A comparative study using prepared and unprepared frozen semen for donor insemination
(1996) Pistorius L.R.; Kruger T.F.; De Villiers A.; Van Der Merwe J.P.
The aim of this study was to compare the efficacy of pericervical insemination with unprepared semen with that of intrauterine insemination with prepared donor semen in a prospective, randomized, crossover clinical trial. Fifty-four subsequent patients who qualified for therapeutic donor insemination were randomized to receive alternately either an intrauterine insemination with thawed frozen donor semen, prepared by double wash and swim-up, or pericervical insemination with unprepared thawed frozen donor semen in subsequent treatment cycles, with each patient serving as her own control. Eleven pregnancies ensued from 54 cycles of intrauterine insemination (20.4% per cycle), and 2 pregnancies ensued from 58 cycles of pericervical insemination (3.4% per cycle, p = .005). Five pregnancies ensued during the first treatment cycle (13.2%), 4 during the second treatment cycle (17.4%), 2 during the third (13.2%), 1 during the fourth (7.1%), and 1 after the fourth treatment cycle (4.8%). The significantly better pregnancy rate from intrauterine insemination with prepared semen supports this treatment option. The decrease in pregnancy rate after the fourth treatment cycle confirms the need for alternative therapy after 4 failed cycles of therapeutic donor insemination.
A comparison of five glucometers in South Africa
(2009) Essack Y.; Hoffman M.; Rensburg M.; Van Wyk J.; Meyer C.S.; Erasmus R.
Objective: To assess the accuracy and precision of five currently available blood glucose meters in South Africa Background: Since the introduction of glucometers, there has been an ongoing, competition-driven development in both meter and strip technology, which has allowed for greater accuracy and reliability of results. Despite the advances in technology, there is significant variation amongst these glucometers necessitating a proper evaluation before use. Methods: Glucose levels in capillary blood samples from 115 patients attending the diabetic clinic at Tygerberg Hospital were measured with each meter, and compared with the laboratory reference method. Results: The coefficients of variation (CVs) (imprecision) of most meters were acceptable at less than 5%, with a bias ranging from 1.7 to 6.8%. None of the glucometers satisfied the American Diabetes Association (ADA) recommendation of less than 5% bias. Conclusions: The study highlights the need for an objective and independent comparison of all glucometers in South Africa, as the variability observed can impact on patient care.
A comparison of heart rate variability in affected and unaffected members of families with progressive familial heart block type I
(1994) Van Der Merwe P.-L.; Weymar H.W.; Kalis N.N.
The presence of sinus bradycardia (less than 60/min) in patients affected by progressive familial heart block type I (PFHB1) and their inability to reach a target heart rate during exercise testing, prompted an investigation of the influence of the autonomic nervous system on cardiac conduction in these family members. Forty members of PFHB1 families, 20 affected and 20 not affected, were included in the study. All were subjected to 24-hour Holter monitoring and treadmill exercise testing (Bruce protocol). Spectral and non-spectral analyses of heart rate variability were performed to evaluate the autonomic nervous system. The results showed that there were no differences between the two groups and that they had normal autonomic nervous systems. It is therefore possible to conclude that the slow heart rate at rest of affected PFHB1 family members and their inability to reach a target heart rate during exercise testing is due to a primarily diseased heart conduction system.
A comparison of omeprazole with ranitidine for ulcers associated with nonsteroidal antiinflammatory drugs
(1998) Yeomans N.D.; Tulassay Z.; Juhasz L.; Racz I.; Howard J.M.; Van Rensburg C.J.; Swannell A.J.; Hawkey C.J.
Background: Suppressing acid secretion is thought to reduce the risk of ulcers associated with regular use of nonsteroidal antiinflammatory drugs (NSAIDs), but the best means of accomplishing this is uncertain. Methods: We studied 541 patients who required continuous treatment with NSAIDs and who had ulcers or more than 10 erosions in either the stomach or duodenum. Patients were randomly assigned to double-blind treatment with omeprazole, 20 mg or 40 mg orally per day, or renitidine, 150 mg orally twice a day, for four or eight weeks, depending on when treatment was successful (defined as the resolution of ulcer and the presence of fewer then five erosions in the stomach and fewer than five erosions in the duodenum, and not more then mild dyspepsia). We randomly assigned 432 patients in whom treatment was successful to maintenance treatment with either 20 mg of omeprazole per day or 150 mg of ranitidine twice a day for six months. Results: At eight weeks, treatment was successful in 80 percent (140 of 174) of the patients in the group given 20 mg of omeprazole per day, 79 percent (148 of 187) of those given 40 mg of omeprazole per day, and 63 percent (110 of 174) of those given ranitidine (P<0.001 for the comparison with 20 mg of omeprazola and P=0.001 for the comparison with 40 mg of omeprazole). The rates of healing of all types of lesions were higher with omeprazole than with ranitidine. During maintenance therapy, the estimated proportion of patients in remission at the end of six months was 72 percent in the omeprazole group and 59 percent in the ranitidine group. The rates of adverse events were similar between groups during both phases. Both medications were well tolerated. Conclusions: In patients who use NSAIDs regularly, omeprezole healed and prevented ulcers more effectivity than did ranitidine.
A critical look at the diagnostic value of culture-confirmation in childhood tuberculosis
(2006) Engelbrecht A.L.; Marais B.J.; Donald P.R.; Schaaf H.S.
Objectives: To describe the clinical presentation, delay in diagnosis and treatment initiation, and outcome of culture-confirmed childhood tuberculosis. Methods: Retrospective study of children < 13 years of age at Tygerberg Children's Hospital, Cape Town, South Africa with culture-confirmed tuberculosis seen January 2002-June 2003. Data were collected by review of hospital and clinic records. Results: Culture-confirmed tuberculosis was diagnosed in 184 children, median age 36 months; 26 (14.1%) were diagnosed clinically and treatment was started before admission. Tuberculosis was newly diagnosed in 158 children; 127 (80.4%) were clinically diagnosed and 31 (19.6%) were diagnosed only after culture result was known (culture-diagnosed). The median time from admission to diagnosis was 1 day (1-21 days) for clinically diagnosed, and 73 (34-178 days) for culture-diagnosed children. Treatment was initiated by hospital physicians in all 127 clinically diagnosed and 14/31 culture-diagnosed children. Of the 17 culture-diagnosed children not started on treatment, 4 were subsequently diagnosed on clinical grounds and treated at clinic level, 8 were found in good health, 4 failed to follow-up and 1 neonate died before the culture result was known. Conclusions: In symptomatic children, the vast majority could be confidently diagnosed on clinical grounds. However, culture-confirmation remains valuable to establish drug susceptibility. © 2006 The British Infection Society.
A diffusion tensor imaging and neuropsychological study of prospective memory impairment in South African HIV positive individuals
(2012) Jacqueline H.; Jenny W.-T.; Jean-Paul F.; Bruce S.; Robert P.; Kevin T.; Dan S.; John J.
HIV-associated prospective memory (ProM) impairment has emerged, in earlier studies as a significant predictor of medication management and independence in activities of daily living. The relationship between ProM and white matter integrity in HIV has not previously been investigated. Participants, including 128 HIV-infected individuals and 32 healthy controls, were assessed using a comprehensive neuropsychological evaluation and both objective and subjective measures of ProM. Diffusion tensor imaging (DTI) was utilized to investigate the relationship of white matter integrity to ProM in a randomly selected subsample of 40 HIV positive subjects, using a whole brain voxel-based approach to define fractional anisotrophy (FA) and mean diffusion (MD). Total prospective memory was significantly poorer in the HIV positive group when compared with healthy controls (p00.023). Timebased ProM was poorer in the HIV group compared to healthy controls both without prompts (p00.001) and with prompts (p00.001). Poor Total ProM score correlated with performance on neuropsychological tests of executive functioning, information processing speed, learning, and working memory (p<0.05). Those HIV positive participants with poor ProM had significantly decreased FA in the regions of superior corona radiata (p00.0035), the corpus collosum (p00.006) and the cingulum (p00.0033) when compared to those who were HIV positive with good ProM. This study reinforces the importance of ProM assessment in HIV. © Springer Science+Business Media, LLC 2012.
A founder BRCA2 mutation in non-Afrikaner breast cancer patients of the Western Cape of South Africa
(2012) van der Merwe N.C.; Hamel N.; Schneider S.-R.; Apffelstaedt J.P.; Wijnen J.T.; Foulkes W.D.
Founder mutations in BRCA1 and BRCA2 have been reported in many different populations. We studied 105 Coloured and 16 Black Xhosa women residing in the Western Cape of South Africa diagnosed with breast cancer. We screened these patients using our standard panel of six previously reported SA Afrikaner and Ashkenazi Jewish BRCA1/2 mutations and identified only two Afrikaner mutations. Further screening by the protein truncation test (BRCA1 exon 11, and BRCA2 exons 10 and 11) revealed an additional four deleterious mutations (BRCA1 c.1504-1508del,p.Leu502AlafsX2, BRCA2 c.2826-2829del,p.Ile943LysfsX16, c.6447-6448dup,p.Lys2150IlefsX19 and c.5771-5774del,p.Ile1924Argfs X38). The latter, also known in Breast Cancer Information Core nomenclature as 5999del4, was identified in 4 of 105 (3.8%) Coloureds and 4 of 16 (25%) Xhosa women, which makes it a frequent founder mutation in the Western Cape Province. Although this mutation was previously reported to occur in the Netherlands, haplotype analysis indicated two distinct origins for the Dutch and South African mutations, excluding the possibility of a common Dutch ancestor and suggesting gene flow from the indigenous tribes such as the Xhosa to the Coloured population instead. Further studies to determine the carrier rate of this variant in the Xhosa and other SA populations are warranted. © 2011 John Wiley & Sons A/S.
A new computerized method of reading sperm morphology (strict criteria) is as efficient as technician reading
(1993) Kruger T.F.; DuToit T.C.; Franken D.R.; Acosta A.A.; Oehninger S.C.; Menkveld R.; Lombard C.J.
Objectives: To compare the ability of a computerized method of sperm morphology with the manually recorded method in predicting in vitro fertilization (IVF) results, to compare results obtained by both methods, and to determine the intraobservation variability. Design, Setting, Patients: Forty-three stained semen slide preparations from two large level-three academic institutions' reproductive endocrinology units (IVF programs) were blindly evaluated, and the sperm were classified into normal and amorphous forms. Results: Experiment 1: Twenty-one slide preparations from the Tygerberg gamete intrafallopian transfer program were manually evaluated; the fertilization rates for the groups with <14% and >14% normal sperm forms were 33.3% (15/45 oocytes) and 76.6% (46/60 oocytes), respectively. Corresponding fertilization rates with FERTECH were 46.8% (30/64) and 75.6% (31/41). Experiment 2: Twenty-two slide preparations from the Norfolk IVF program were evaluated. The manual method reported a fertilization rate in the group with <14% normal forms of 27.4% (14/51 oocytes) compared with 90.0% (127/141 oocytes) in the group with >14% normal forms. Corresponding figures for the FERTECH method were 33.9% (18/53) and 88.4% (123/139), respectively. Experiment 3: When the 43 slide preparations were blindly evaluated using both methods, 84% of the FERTECH evaluations correlated well with the manual method and FERTECH ability to diagnose the subfertile male (<14% normal forms) was 95% (sensitivity). Experiment 4: A total of 16 different slides (8 per group) were randomly selected and analyzed five times (100 cells per reading) by the computerized method. The slides were obtained from men with normal sperm morphology of <14% and >14% as classified by the manual method. In the first group (<14%) 97.5% (39/40) of the readings classified the sperm in the proper category, whereas in the second group (>14%) 95% (38/40) of the cases were correctly identified. Conclusion: Using strict criteria for morphology evaluation, there is a positive and significant correlation between FERTECH evaluation and manual assessment. The reproducibility of the computerized method and the ability to distinguish between fertile and subfertile groups using those criteria are good.
A new type of minocycline-induced cutaneous hyperpigmentation
(2004) Mouton R.W.; Jordaan H.F.; Schneider J.W.
Pigmentary disorders are recognized adverse effects of the semi-synthetic tetracycline derivative antibiotic, minocycline. Three distinct types of minocycline-induced cutaneous pigmentation have been described. Type I, blue-black pigmentation confined to sites of scarring or inflammation on the face: Type II, blue-grey circumscribed pigmentation of normal skin of the lower legs and forearms; and Type III, diffuse muddy brown pigmentation of normal skin accentuated in sun-exposed areas. We report two patients with acne vulgaris with a fourth type of minocycline-induced cutaneous pigmentation. They presented with circumscribed blue-grey pigmentation within acne scars confined to the back. Histology showed pigment within dendritic cells, and extracellularly throughout the dermis. Histochemistry identified a calcium containing melanin-like substance. Iron was absent. Immunohistochemistry confirmed some pigment-containing cells to be macrophages. Electron microscopy demonstrated electron-dense granules, free and membrane-bound, within macrophages and fibroblast-like cells. Energy-dispersive X-ray analysis confirmed the presence of calcium. Iron was absent. This fourth type of cutaneous minocycline hyperpigmentation may be a variant of Type I, but based on clinical, pathological and microanalytical differences, appears to be a new entity. The pigment may be a drug metabolite-protein complex chelated with calcium, or an insoluble minocycline-melanin complex. We propose a classification of cutaneous minocycline pigmentation based on clinico-pathological criteria.

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