Background: Chloride and adenosine deaminase measurements in cerebrospinal fluid are still sporadically requested as part of tuberculous meningitis work-up. In the literature, evidence is contradictory and opinion is divided on their utility in clinical practice. The accuracy of both for the early presumptive diagnosis of tuberculous meningitis was investigated in patients in a region with high prevalence of tuberculosis and HIV infection in order to inform a decision on whether to continue offering these tests to clinicians. Methods: A retrospective descriptive study of diagnostic accuracy was conducted at the National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa. Data were collected on all cerebrospinal fluid specimens submitted for tuberculosis culture between 1 January 2012 and 31 December 2014. Chloride and adenosine deaminase concentrations were compared with automated liquid culture for Mycobacterium tuberculosis as the reference standard. Findings: There were 2531 cerebrospinal fluid specimens submitted for tuberculosis culture during the study period; exclusion of duplicates yielded 2081 specimens. Chloride was requested on 711 (34·2%) specimens; 44 (6·2%) were tuberculosis culture-positive. Adenosine deaminase was requested on 152 (7·3%) specimens; 20 (13·2%) were culture-positive. Chloride sensitivity (<120 mmol/L) for the detection of tuberculous meningitis was 93·2% (95% confidence interval 81·3-98·6), with specificity 62·4% (58·6-66·1), positive predictive value 14% (10·3-18·6), negative predictive value 99·3% (97·9-99·9), positive likelihood ratio 2·48 (2·18-2·81), and negative likelihood ratio 0·109 (0·037-0·326). Adenosine deaminase sensitivity (>6 U/L) was 70% (45·7-88·1), specificity 89·4% (82·8-94·1), positive predictive value 50% (30·6-69·4), negative predictive value 95·2% (89·8-98·2), positive likelihood ratio 6·6 (3·72-11·7), and negative likelihood ratio 0·336 (0·171-0·657). Interpretation: In this patient population chloride and adenosine deaminase showed at best only modest performance as markers of tuberculous meningitis. However, very good negative predictive values could serve to identify patients highly unlikely to have the disease.

Nine human mucin genes have been described, which express glycoproteins MUCJ,2,3,4 ,5AC,5B,6, 7, and 8 in various tissues. It has been shown that different mucins are expressed in various gastric disease states as compared to the normal. In this study histochemical and immunohistochemical methods were used to determine the type of mucin and the pattern of staining in 54 patients with a variety of gastric conditions [i.e. normal controls, foetal stomachs, chronic active gastritis, low grade dysplasia, intestinal metaplasia (associated with gastritis, benign ulcers, dysplasia and cancer), early and advanced intestinal type adenocarcinoma, and diffuse adenocarcinoma]. MUCJ-7 antibodies were used in the study, this being the first study to all assess seven MUC antibodies in the various conditions. It is also the first study to assess the pattern of mucin staining in foetal stomachs. Normal controls were immunoreactive for MUC4, 5 and 6, and gastritis specimens showed similar results, although the latter showed more MUCJ immunoreactivity. Whereas early foetal stomach showed no MUC immunoreactivity, MUC4, 5 and 6 were present from the early second trimester onwards. There was no significant difference between dysplasia and intestinal metaplasia, both categories showing expression of MUC2 and 3 predominantly. Early intestinal type adenocarcinomas did not show any mucins in the majority of cases. Advanced intestinal type adenocarcinomas showed immunoreactivity predominantly for MUCJ, 5 and 6, as well as MUC2 in some cases. Diffuse adenocarcinomas showed strong positive MUC2 and MUC6 staining, and in some cases MUC5 and 7. In conclusion this study has shown different patterns of mucin immunoreactivity in various gastric disease states. Specimens with dysplasia, intestinal metaplasia, late intestinal type adenocarcinoma and diffuse gastric cancer were characterized by increased diversity of mucin gene expression, whereas early intestinal cancer showed loss of mucin immunoreactivity.

Gonadotropin-releasing hormone (GnRH), a central regulator of reproductive function in all vertebrates, exerts its effects via binding to the GnRH receptor (GnRHR) in the pituitary gonadotrophs. The GnRHR is a member of the G-protein coupled receptor (GPCR) superfarnily. A second form of the GnRHR (type II), other than the pituitary gonadotrope GnRHR (type I) has been proposed to exist and to play a role other than the classical endocrine role of the pituitary GnRHR. Elucidation of amino acid residues of the GnRHR that are crucial for ligand binding, activation of the receptor, and coupling to the G-protein, is important in understanding structure-function relationships towards the design of drugs for therapeutic intervention. Such information can often be deduced by a comparison between conserved and non-conserved amino acid residues of GnRHRs from different species. At the start of this project no non-mammalian or invertebrate, and only some of the eutherian mammalian type I GnRHRs had been cloned. The aim of this project was to clone novel GnRHRs, i.e. type I and type II GnRHRs from redbait and mole and type II mouse and human GnRHRs using polymerase chain reaction (PCR) strategies. PCR was performed with degenerate primers designed to human type I GnRHR to areas that are not conserved between GPCRs in general, but are conserved between mammalian GnRHRs.

Includes bibliographical references. / Arrhythmogenic right ventricular cardiomyopathy / dysplasia (ARVC/D) is a genetic disease causing fibro-fatty replacement of the right ventricular myocardium, resulting in cardiac arrhythmias and sudden death. Part of the diagnostic work up for these patients includes a biopsy of the endocardium which has historically been difficult to interpret and of limited value in the early stages of disease. This study will focus on novel immunohistochemical stains of the cardiac desmosomes. These will be used to try to aid in the early diagnosis of ARVC.

Includes bibliographical references (leaves 171-184). / Affected members of the family investigated in this dissertation presented with photosensitivity and raised red cell protoporphyrin concentrations, indicative of protoporphyria. Further examination of this family revealed features that were atypical of erythropoietic protoporphyria. These included a highly penetrant disease, disease severity as expressed by more prevalent hepatic complications, a preponderance of protoporphyrin in its zinc chelated form, a therapeutic response to iron supplementation, and an absence of mutations in the ferrochelatase gene or haplotype markers associated with erythropoietic protoporphyria. We have reviewed clinical data from this family, established a ferrochelatase enzyme assay in our laboratory, and shown normal ferrochelatase enzyme activity in affected subjects.

Includes bibliographical references. / Objective: To investigate the difference in expression of CD146 immunohistochemical staining on intermediate trophoblast in early and late onset pre-eclampsia placentas as well as comparing this expression to gestational age matched control placentas. Study Design: Retrospective case series of 100 placentas: 25 early onset and 25 late onset pre-eclampsia placentas as well as 25 early and 25 late gestational age matched control placentas. Placentas were obtained from patients delivering in Tygerberg Hospital. Methods: Placentas were routinely fixed and processed. 2 sections of one preselected block from each case was cut and stained with CD146 and MNF116 immunohistochemical stain. The expression of the staining would be performed by means of analytical and image analysing software. Results: The study failed to demonstrate differences in CD146 expression by the intermediate trophoblast in the pre-eclampsia and control placentas. The analytical approach was deemed to be subjective and the image analysing software had too much background staining and inaccurate identification of the intermediate trophoblast in order to produce reproducible consistent results. Conclusion: Dual staining, using immunofluorescent staining of CD146 and MNF116 on smaller biopsies of the decidua are thought to be able to produce much better material for image analyses software.

Complete suicides and parasuicides are a major cause of death and disability in South Africa and the rest of the world. The epidemiology, pathology and toxicology of complete suicides were investigated in this study. All the complete suicide cases, which were presented to Salt River Medicolegal Laboratory over a period of one year (1 January 1997 - 31 December 1997), were analysed. The candidate personally conducted 148 of the alleged 180 suicide cases that presented in this time period (82%). The candidate did all the follow up investigations herself. The main findings were: 1. The male to female ratio was 5: 1. (131: 26) 2. Shooting and hanging were the most commonly used methods. 3. The racial distribution of violent deaths showed a high rate of suicides amongst the White population. 4. Suicides accounted for the Joss of young lives, the average age being 37,8 years. The mean age was 34 years. 5. Most victims committed suicide in and around their own homes. 6. The majority did not leave suicide notes. 7. Psychiatric disorders, poor health, arguments with close family members and friends, financial problems and long-standing relationship problems were the most common reasons for the suicides. 8. Suicides by prisoners accounted for 3,8% of the study (6 cases). 9. Two cases of double suicide (group suicide) were identified. 10. Five cases of homicide-suicide were identified in the study material. 11. One case of an attempted suicide by means of a high-speed motor vehicle accident, followed by the successful suicide by other means, was identified.

Objective: Thyroid cancer affects approximately 298 million people worldwide and the major challenge is reliably distinguishing patients who present with poor prognosis from those who do not. There are genetic markers that have been shown to be associated with poor clinical outcome in thyroid cancer, which include mutations in the BRAF and RAS genes. In addition to genetic variation, recent studies have reported on the effects of micro-ribonucleic acids' (miRNAs) differential expression observed in tumour and normal tissue as another possible marker of thyroid cancer prognosis. Therefore, miRNA expression signatures in thyroid cancer could be used as biomarkers for prognosis and diagnosis. This study compared the expression of miRNAs in papillary thyroid cancer and follicular thyroid cancer. Methods: As part of a preliminary study, 66 differentiated thyroid cancer samples were obtained from patients attending Groote Schuur Hospital and used in the study. MiRNA miScript polymerase chain reaction (PCR) Array (Qiagen) was used to determine the differential miRNA expression profiles between follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC). Real time PCR was employed to confirm the expression levels of miRNA- 21 and miRNA-122. Results: 17 miRNAs were upregulated in PTC and 14 in FTC. There were significant differences in the miRNA expression between FTC and PTC. For example, miRNA-21 was the most upregulated miRNA in PTC and miRNA-122 in FTC. We found no correlation of the expression of these miRNAs to clinicopathological features. We observed an association of BRAF mutation positivity to advanced tumour stage and advanced age of presentation however, no correlation was seen to miRNA-21 or miRNA-122 expression. Conclusion: Although we did not observe correlations between miRNAs and any of the clinicopathological features, microRNA expression profile signatures were able to differentiate between PTC and FTC and could potentially be further validated as diagnostic markers.

The Dalmatian coach hound, when compared to other dog breeds, exhibits three characteristic abnormalities of uric acid metabolism, namely hyperuricaemia, hyperuricosuria and increased renal uric acid clearance. These properties are associated with hypoallantoinaemia and hypoallantoinuria. A result of these abnormalities is a high incidence of urate urolithiasis in this breed. Other diseases such as recurrent dermatitis, chronic cystitis and deafness are also found in the Dalmatian and whether there is any causal relationship with the uric acid disorder is unknown. In terms of the quantity of uric acid excreted, the Dalmatian dog resembles man more closely than the non-Dalmatian. On the other hand, in its high renal urate clearance, this breed of dogs differs from man, whose renal clearance values are lower and therefore closer to those of the non-Dalmatian. In this respect the Dalmatian resembles man affected with the inborn renal urate transport defect of renal hypouricaemia. The significance of uric acid metabolism in the Dalmatian has attracted many investigators in search of the underlying metabolic defect(s). Study of the Dalmatian may also be relevant to the understanding of disorders of purine metabolism in man for example hyperuricosuria, uric acid urolithiasis and hereditary renal hypouricaemia.

Includes bibliographical references (leaves 64-71). / Cyclin E and p27 expression is easy to assess in human tissues by standard immunohistochemical techniques. Immunohistochemistry is cost effective, relatively easy to perform and will play more of a role in the future management of cancer. To investigate the role of p27 and cyclin E immunoexpression as a prognostic factor in early breast carcinoma. Cyclin E and p27 immunohistochemistry was performed on sixty six cases of breast carcinoma submtted over a five year period to the Division of Anatomical Pathology, Groote Schuur hospital; Whittaker and Associates; and PathCare. All tumours included in this study were less than 5cm in diameter (pT1 and pT2 stage) and all the patients had wide local excisions peformed. Follow up information was obtained from patient folders in the Department of Radiation Oncology.