28 results match your criteria: "South African Institute for Medical Research and University of the Witwatersrand[Affiliation]"
Diagn Cytopathol
April 2004
Cytopathology Unit, School of Pathology of the South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
This study was undertaken to determine the value of incorporating fluorescence into cytopathological evaluation of lymph node fine-needle aspiration (FNA) specimens suspected of harboring mycobacterial species. The study population consisted of 1,044 HIV-positive and -negative patients referred for FNA to the cytopathology unit of a South African medical school located in a very high HIV prevalence region. Each aspirate was assessed on routine Papanicolaou-stained slides for morphologic characteristics of mycobacterial infection.
View Article and Find Full Text PDFAm J Phys Anthropol
October 2002
Department of Human Genetics, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa 2001.
The extent of genetic differentiation between seven South African Bantu-speaking groups (Zulu, Xhosa, Tsonga/Shangaan, Southern Sotho, Pedi, Tswana, and Venda) was assessed from coancestry coefficients (F(ST)) estimated from autosomal serogenetic, DNA, and Y-chromosome DNA haplotypes. The overall F(ST) obtained from the autosomal data was 0.002, and that from the Y chromosome data was 0.
View Article and Find Full Text PDFCurr Opin Infect Dis
April 2001
Wits/MRC Pneumococcal Diseases Research Unit, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, South Africa.
This review describes recent contributions to our understanding of pneumococcal pneumonia. Two genes have been described that encode enzymes involved with the biosynthesis of muropeptides. These enzymes may be novel antibiotic targets.
View Article and Find Full Text PDFPediatr Hematol Oncol
March 2002
Department of Haematology and Molecular Medicine, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
This study compared hematological reference ranges in black very low birth weight infants to previously published values established predominantly on white subjects. Ninety-four healthy, black, premature babies with a birth weight of 800 to 1500 g at 2-7 days of age were enrolled as part of a study comparing blood transfusions and high- versus low-dose recombinant erythropoietin in anaemia of prematurity. Peripheral venous blood was collected for a full blood count and differential, fetal hemoglobin and erythropoietin levels.
View Article and Find Full Text PDFPediatr Infect Dis J
February 2002
Pneumococcal Diseases Research Unit of the Medical Research Council, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
Background: Despite their proven efficacy Haemophilus influenzae type b (Hib) conjugate vaccines are not given to most children in the developing world in the face of an estimated global Hib disease burden of nearly 2 million cases per annum. A major barrier to the introduction of the vaccine would be overcome by diluting the vaccine 10-fold in diphtheria-tetanus-whole cell pertussis (DTP). We report a randomized trial comparing the use of Hib conjugate vaccine diluted in a multidose vial of DTP with that of the full Hib dose.
View Article and Find Full Text PDFAm J Hum Genet
March 2001
Department of Human Genetics, School of Pathology, The South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, 2000, South Africa.
In southern Africa, brown oculocutaneous albinism (BOCA) is a distinct pigmentation phenotype. In at least two cases, it has occurred in the same families as tyrosinase-positive oculocutaneous albinism (OCA2), suggesting that it may be allelic, despite the fact that this phenotype was attributed to mutations in the TYRP1 gene in an American individual of mixed ancestry. Linkage analysis in five families mapped the BOCA locus to the same region as the OCA2 locus (maximum LOD 3.
View Article and Find Full Text PDFClin Genet
January 2001
Department of Human Genetics, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
The spectrum of CFTR mutations in three South African populations is presented. To date. a total of 192 white patients (384 chromosomes) with confirmed CF have been tested.
View Article and Find Full Text PDFEur J Cancer
August 2000
Department of Anatomical Pathology, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
E-cadherin and the associated catenin complex have been recognised as performing a key role in cell adhesion. Loss of cell adhesion is seen as a key step in the cascade leading to tumour metastasis. The ability of both extra- and intracellular factors to regulate E-cadherin-mediated cell adhesion in physiological processes has provided insight into both the interactions of the E-cadherin-catenin complex, and possible mechanisms utilised by tumours in the process of metastasis.
View Article and Find Full Text PDFDiagn Cytopathol
May 2000
Cytopathology Unit, Department of Anatomical Pathology, School of Pathology of the South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
Pemphigus vulgaris is an autoimmune disease characterized by acantholytic blisters and erosions involving the oral mucosa, skin, and less frequently other mucosal surfaces. Although the cytology of scrapings from the cutaneous and oral lesions has been well-documented, there are relatively few reports in the literature of the cytologic appearance of pemphigus on cervicovaginal smears. This report documents a case of pemphigus involving the cervix, in which the diagnosis was not known at the time of the cervical smear and biopsy.
View Article and Find Full Text PDFAnn Clin Biochem
March 2000
Department of Chemical Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Auto-antibodies to oxidized low-density lipoprotein (ox-LDL) are thought to play a pivotal role in the pathogenesis of atherosclerosis. This study investigates the value of auto-antibodies to ox-LDL as a predictive marker of atherosclerosis in patients with both homozygous and heterozygous familial hypercholesterolaemia (FH), who are known to suffer from severe premature atherosclerosis. The influences of well-established risk factors for atherosclerosis such as age, LDL-cholesterol levels and smoking on the results were also determined.
View Article and Find Full Text PDFClin Chim Acta
March 2000
Department of Chemical Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
Adhesion of leukocytes to endothelial cells via cell adhesion molecules (CAMS) is thought to be pivotal in the initiation of atherosclerosis. As patients with familial hypercholesterolaemia (FH) are known to develop severe, premature coronary artery disease (CAD), we investigated the usefulness of soluble forms of CAMS namely vascular cellular adhesion molecule-1 (VCAM), intercellular cell adhesion molecule-1 (ICAM) and E-selectin as predictive markers of the presence and severity of atherosclerosis in this patient group. Twenty heterozygous FH patients without CAD; 24 heterozygous FH patients with CAD; 17 homozygous FH patients without documented CAD; nine homozygous FH patients with overt CAD; and 50 healthy controls were studied.
View Article and Find Full Text PDFJ Clin Microbiol
February 2000
Department of Clinical Microbiology and Infectious Diseases, South African Institute for Medical Research and University of the Witwatersrand, University of the Witwatersrand, Johannesburg, South Africa.
Acanthamoeba species can cause a chronic, progressive ulcerative keratitis of the eye which is not responsive to the usual antimicrobial therapy and is frequently mistaken for stromal herpes keratitis. An unusual case of coinfection with Acanthamoeba polyphaga and Pseudomonas aeruginosa as causes of corneal keratitis in a contact lens wearer from Gauteng, South Africa, is reported. These two pathogens have previously been assumed to be selectively exclusive.
View Article and Find Full Text PDFHum Mutat
February 2000
Department of Human Genetics, The South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
Oculocutaneous albinism (OCA) is an inherited disorder resulting in hypopigmentation of the skin, hair, and eyes. OCA type 2 (tyrosinase-positive) is the most common recessively inherited disorder among southern African Blacks. OCA2 is also seen in southern African Caucasoids, but is less frequent.
View Article and Find Full Text PDFPrenat Diagn
March 1999
Department of Human Genetics, The School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg, South Africa.
We present a family in which the first affected child presented with a 'milder' form of the hydrolethalus syndrome and survived to seven months, and two subsequent pregnancies with typical features detected early by ultrasound evaluation. We propose that the 'milder' cases are indeed true cases of the hydrolethalus syndrome and that allelic variability may be responsible for these 'non-typically Finnish' findings. We also demonstrate that, especially in families where there has been a previously affected fetus, echographic diagnosis can be made in the first trimester, as early as the 11th week of gestation.
View Article and Find Full Text PDFCancer
February 1999
Department of Anatomical Pathology, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Background: An investigation into the determination of cytomorphologic criteria that may distinguish papillary serous carcinoma of the endometrium (PSC) from typical endometrioid carcinoma (TEC) in cervical smears was undertaken. Preoperative identification of this poor prognostic variant of endometrial carcinoma may influence the surgical management of these cases and the choice of adjuvant therapy.
Methods: The cervical smears of 12 cases of histologically confirmed PSC; 12 cases of TEC, including 2 villoglandular/papillary variants, and 6 cases of mixed PSC and papillary endometrioid carcinoma were reviewed.
Twin Res
June 1998
Department of Human Genetics, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Birth statistics for the Johannesburg Metropolitan Region were collected for 757 151 confinements from 1969 to 1989 (467513 Black, 194375 White, 67250 Coloured and 28013 Indian confinements). From 1969 to 1978 data on the sexes of twins were also collected for 375 203 of the confinements (203 504 Black, 129 631 White, 28 253 Coloured and 13 815 Indian confinements). A twin confinement was defined as two deliveries during one confinement.
View Article and Find Full Text PDFJ Infect
November 1998
Department of Clinical Microbiology and Infectious Diseases, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
We report a case of endocarditis and associated paravalvular abscess due to Rothia dentocariosa which did not respond to antibiotic therapy. Nine case reports describing endocarditis caused by this organism, formerly thought to be non-pathogenic, have been recorded in the literature. The isolates were extremely sensitive to penicillin, and eight patients responded to this agent which, in most cases, was used in combination with an aminoglycoside.
View Article and Find Full Text PDFMov Disord
July 1998
Department of Human Genetics, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand.
Huntington's disease is an autosomal-dominant inherited progressive neurodegenerative disease associated with an expanded trinucleotide repeat (CAG) sequence on the short arm of chromosome 4. The disease is considered rare in Africans. We report five black South African families of different ethnic origin with proven expansions typical of Huntington's disease and discuss the possible origins of the disease in Africa.
View Article and Find Full Text PDFInt J Gynecol Pathol
January 1998
Department of Anatomical Pathology, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
A 52-year-old woman underwent a hysterectomy for a large tumor of the uterine cervix that was shown to be a xanthomatous leiomyosarcoma (LMS) by histologic examination, the first example of this tumor in this site. Two previous similar tumors have been reported in the uterine corpus.
View Article and Find Full Text PDFAm J Hum Genet
August 1997
Department of Human Genetics, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Keratolytic winter erythema (KWE), also known as "Oudtshoorn skin disease," or "erythrokeratolysis hiemalis," is an autosomal dominant skin disorder of unknown etiology characterized by a cyclical erythema, hyperkeratosis, and recurrent and intermittent peeling of the palms and soles, particularly during winter. Initially KWE was believed to be unique to South Africa, but recently a large pedigree of German origin has been identified. The disorder occurs with a prevalence of 1/7,000 in the South African Afrikaans-speaking Caucasoid population, and this high frequency has been attributed to founder effect.
View Article and Find Full Text PDFJ Antimicrob Chemother
June 1997
Department of Medical Microbiology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Trovafloxacin had greater in-vitro activity than comparative fluoroquinolone agents against penicillin-sensitive pneumococci in studies from the USA, UK, Slovakia, Czech Republic, Sweden and South Africa. This activity was maintained against penicillin-resistant strains, with MIC90 values of < or = 0.25 mg/L observed for both groups.
View Article and Find Full Text PDFBr J Haematol
June 1997
Department of Human Genetics, The South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
The feasibility of DNA diagnosis for haemophilia A was tested in South African patients and families by screening for the common inversion mutation in the factor VIII gene and for the intragenic microsatellite markers in introns 13 and 22. The allele frequencies at the two microsatellite loci were significantly different, with informativity being higher in the Negroid (100%) than the Caucasoid group (67%). In severely affected haemophiliacs the inversion was found in 43% (6/14) of Negroids but in only 32% (13/41) of Caucasoids.
View Article and Find Full Text PDFHum Genet
April 1997
Department of Human Genetics, School of Pathology, The South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Oculocutaneous albinism (OCA2) is the most common autosomal recessive disorder in the South African Negroid population, occurring with a prevalence of 1/3900 individuals. The OCA2 locus, P, has been mapped to chromosome 15q11-q13 and a 2.7-kb interstitial deletion has been found to be the common mutation in Africa.
View Article and Find Full Text PDFAm J Hum Genet
November 1996
Department of Human Genetics, School of Pathology, The South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
The Lemba are a southern African Bantu-speaking population claiming Jewish ancestry. Allele frequencies at four different Y-specific polymorphic loci, as well as extended-haplotype frequencies that included data from several loci, were analyzed in an attempt to establish the genetic affinities and origins of the Lemba. The results suggest that > or = 50% of the Lemba Y chromosomes are Semitic in origin, approximately 40% are Negroid, and the ancestry of the remainder cannot be resolved.
View Article and Find Full Text PDFS Afr Med J
July 1992
Department of Human Genetics, School of Pathology, South African Institute for Medical Research and University of the Witwatersrand, Johannesburg.
Cystic fibrosis (CF) is a common autosomal recessive disorder among people of European origin. With the localisation of the gene locus to chromosome 7q31 and the identification of closely linked polymorphic markers in 1985, it became possible to offer prenatal testing to couples at risk of having CF children, provided a live affected individual from that family was available for investigation. The CF gene, named CFTR, was cloned and sequenced in 1989 and the most common CF-causing mutation, delta F508, identified.
View Article and Find Full Text PDF