PubMed Health⌕ Search

Biomedical subjects

G Joubert

Publications and source records attributed to G Joubert.

At least 37 records · Page 2Linked to original sources
PubMed2001

Fanconi anemia. a statistical evaluation of cytogenetic results obtained from South African families.

Fanconi anemia (FA) is a rare autosomal recessive genetic disorder showing progressive bone marrow failure, and various phenotypic abnormalities. The lymphocytes show an increased sensitivity to the clastogenic agents diepoxybutane (DEB) or mytomycin C (MMC), measured as chromosomal aberrations. Statistical analysis of chromosome aberration yield showed that: (i) differentiation between obligate carriers and the control group was not possible; (ii) homozygotes were clearly distinguishable from heterozygotes as well as from controls by analyzing only 20 metaphase spreads per person; (iii) most of the FA patients had only one cell line present as measured by distribution of chromosomal damage among cells analyzed; (iv) and when the DEB sensitivity of a patient was high, the amount of cells without damage was low.

Case-Control Studies↗
PubMed2001

A prospective clinical and urodynamic study of bladder function during and after pregnancy.

The aim of the study was to determine whether clinical and/or urodynamic changes in bladder function occur during pregnancy. Assessment consisted of a urinary symptom questionnaire, urogynecological examination and urodynamic investigations, which were repeated 6 weeks after pregnancy. Sixty-six patients had the initial and 40 the follow-up assessments. Statistical analysis was done by 95% confidence intervals (95% CI). Nocturia, frequency, dysuria, urgency and stress incontinence occurred significantly more frequently during pregnancy. Urinary tract infection was diagnosed in 18% of patients during pregnancy and asymptomatic bacteriuria in 9%. Genuine stress incontinence was diagnosed in 12% during pregnancy and in none after pregnancy (95% CI 1% to 24%). An unstable detrusor was diagnosed in 23% of patients during pregnancy and in 15% after pregnancy (95% CI -8% to 23%). Strong desire to void, urgency, maximum cystometric capacity, maximum flow rate and average flow rate were all statistically significantly decreased during pregnancy. It is concluded that significant changes occur in bladder function during pregnancy.

Adult↗
PubMed2001

HIV/AIDS-related knowledge, attitudes and practices among South African military recruits.

OBJECTIVES: To assess the level of HIV-related knowledge, as well as high-risk behaviour and attitudes towards HIV, in a group of South African National Defence Force (SANDF) recruits. DESIGN: Cross-sectional study. SETTING: Tempe military base in Bloemfontein. SUBJECTS: Three hundred and thirty-nine recruits from one company. OUTCOME MEASURES: HIV-related knowledge, attitudes and practices based on a self-administered questionnaire. RESULTS: All of the recruits were male, and most of them (81.4%) were black. The majority of recruits (98.5%) were between 18 and 24 years old. They had a good level of knowledge regarding HIV and AIDS, with more than 80% giving a correct response in most cases. However, several important misconceptions regarding HIV/AIDS and its transmission still exist. Furthermore, several recruits still practised high-risk behaviour, such as not using condoms with casual or new partners. Most obtained their knowledge regarding HIV/AIDS from schools (34.8%), health and social services (27.1%) and the printed media (17.7%), while only 5.2% stated that they learnt about HIV/AIDS from the SANDF education programmes. CONCLUSION: Efforts towards initiating behaviour changes in military recruits should be intensified, and if necessary education programmes should be adapted to facilitate achievement of this goal.

Adolescent↗
PubMed2000

Characterization at the single-cell level of naive and primed CD8 T cell cytokine responses.

The aim of this study was to characterize differences between naive and primed CD8 T cells. Our results show that (i) naive and primed CD8 T cells display similar activation thresholds, with no direct evidence for a difference in their TCR signals, and (ii) primed cells differ mainly in their capacity to secrete IFN-gamma. A comparison of the two populations at the single-cell level demonstrated that the increased production of IFN-gamma by the primed cell subset is due to a larger proportion of single cells that are able to synthesize this cytokine early following activation. These results indicate that the intrinsic effector capabilities of individual CD8 T cells expressing the same TCR are heterogeneous and that cells with identical antigen specificity but increased effector capacities are generated or selected during the primary response.

Animals↗
PubMed2000

Allelic frequencies of host genetic variants influencing susceptibility to HIV-1 infection and disease in South African populations.

OBJECTIVES: Limited information is available on the prevalence in African populations of host genetic polymorphisms conferring resistance to HIV-1 infection and disease. The objective of this study was to determine the allelic frequencies in South African populations of the chemokine receptor gene variants CCR5delta32, CCR5m303 and CCR2b-641 and the CXCR4 ligand gene variant SDF1-3'A. METHOD: Cross-sectional study to determine the prevalence of these gene variants in South African subjects of African and European descent. RESULTS: The CCR5delta32 genetic variant is rare in individuals of African origin, having an allelic frequency of 0.1% (n = 1247) compared with 9.8% (n = 144) in Caucasians. The CCR5m303 mutation was not detected in Africans (n = 687), whereas an allelic frequency of 0.9% (n = 145) was identified in Caucasians. The frequency of CCR2b-641 allele was 13.1% (n = 180) in Africans, which was significantly higher that the 7.2% (n = 146) detected in Caucasians. Finally the allelic frequency of the SDF1-3'A gene variant was only 1.0% (n = 198) in Africans compared with 19.8% (n = 145) in Caucasians. CONCLUSIONS: These results indicate that genetic polymorphisms conferring resistance to HIV-1 infection are rare in the South African Black population. Except for the CCR2b-641 gene variant, individuals of African origin also had a much lower prevalence of genetic variants associated with prolonged disease progression.

Alleles↗
PubMed2000

Nutritional status of preschool children in informal settlement areas near Bloemfontein, South Africa.

OBJECTIVE: To determine the nutritional status and household resources of preschool children. DESIGN: A cross-sectional survey. SETTING: : Two informal settlement areas, Joe Slovo (JS) and JB Mafora (JBM) in Mangaung, near Bloemfontein, South Africa. SUBJECTS: Preschool children (<72 months) of a randomly selected sample of households in JS (experimental) (n = 162) and JBM (control) (n = 186) were included. Standard methods were used to obtain household and care-giver particulars, weight and height measurements, blood and stool samples, and 24-hour dietary recalls. RESULTS: Breast-feeding and dietary intake in the two areas were nearly similar; breast-feeding was continued for 12 months and longer. Although the children's total protein intake was sufficient, their energy intake was low. A low median intake of micronutrients prevailed, including iron, zinc, calcium, niacin, riboflavin, thiamine and vitamins C, B6, A and D. The prevalence of being underweight (JS = 19.8%; JBM = 18.8%), stunted (JS = 29%; JBM = 21. 5%) and wasted (JS = 6.5%; JBM = 3.7%) were fairly similar in both areas, as well as the prevalence of marginal vitamin A deficiency, anaemia, iron deficiency and parasite infestations. No significant associations could be found between household and nutritional status indicators, probably due to the small number of well-nourished children and the generally poor household situation of the participants. CONCLUSIONS: The generally poor nutritional status and environmental conditions emphasize the urgency of intervention for these children.

Anthropometry↗
PubMed2000

Application of the new ADA criteria for the diagnosis of diabetes to population studies in sub-Saharan Africa. American diabetes association.

AIMS: To examine the implications for epidemiological studies of the American Diabetes Association (ADA) recommendation that the fasting blood glucose at a lowered level becomes the main diagnostic test for diabetes on cross-sectional-based data from sub-Saharan Africa. METHODS: Data from 11 surveys conducted in rural, peri-urban and urban Cameroon (n = 1804), South Africa (n = 3799) and Tanzania (n = 10013) which measured fasting (ADA criteria) and 2-h blood glucose concentrations during a standard 75 g OGTT (old WHO criteria) were analysed. RESULTS: The prevalence of diabetes was higher in eight of the 11 surveys when applying the new ADA compared to the old WHO criteria. With the exception of one population (Mara, Tanzania) the absolute difference in prevalence between the two classifications tended to be small (< 2%). There was considerable variation in the categorization of individuals using the ADA and old WHO criteria. The level of agreement between the two ranged from fair to good (Kappa statistic 0.17-0.86). The prevalence of impaired fasting glycaemia (IFG) was lower than that of impaired glucose tolerance (IGT) in 10 of the surveys and the agreement between the two was fair, < or = 0.26 in all the surveys. CONCLUSIONS: Although the use of the new ADA fasting criteria for prevalence surveys is an attractive and practical option, particularly in Africa, further information is required on the characteristics and prognosis of individuals classified as IFG or diabetic by the fasting criteria, prior to wide adoption of the ADA criteria. Ideally measurement of both fasting and two low glucose concentrations should remain the standard for epidemiological studies.

Adult↗
PubMed2000

Variation in utilization of computed tomography scanning for the investigation of minor head trauma in children: a Canadian experience.

OBJECTIVES: To compare the utilization rates of CT scans in investigating minor head trauma in children in Canada, to identify the injuries determined by these scans, and to identify clinical findings that are highly associated with its diagnosis and the injury itself. METHODS: A retrospective cohort study involving nine pediatric hospitals in Canada was conducted. A structured data collection method was used. Inclusion criteria included age 16 years or less, history of blunt head trauma, and a Glasgow Coma Scale score (GCS) greater than or equal to 13. Data collected included demographic information, type of injury, relevant clinical information, computed tomography (CT) scan data, and clinical outcome. Clinical findings associated with CT scan and positive CT scan were identified using logistic regression. RESULTS: One thousand one hundred sixty-four children were included in the study. One hundred seventy-one (15%) had a CT scan, of which 60 (35%) were abnormal. There was a significant difference in the rate of ordering of CT scans among the participating hospitals, but no significant difference in the rate of abnormal CT scans. Mechanism of injury, GCS, and loss of consciousness were significantly related to the presence of an abnormal CT scan. CONCLUSIONS: Although there is a significant difference in the utilization of CT scans to investigate minor head trauma in children across Canada, there is no significant difference in the frequency of head injuries in these patients. This suggests that it may be possible to determine clinical criteria that are predictive of a head injury in these patients.

Adolescent↗
PubMed2000

[Axillary temperature compared to tympanic membrane temperature in children].

The purpose of the study was to measure the axillary temperature at three, six and nine minutes in a hundred children between the ages of one and twelve years who were selected in a non-random deliberate way, and to compare the measurements with the tympanic membrane temperature (golden standard) which was measured in the test persons at the same time. The results were described by sensitivity, specificity, limits of agreement, and predictive values. From some of the findings of the research it is apparent that the axillary temperature reading increased after measurement of three, six and nine minutes. A maximum temperature reading was reached after three minutes in only 9% of the test persons, in 25% after six minutes and in 66% after nine minutes. From the findings it is clear that the ranges that were used influenced the sensitivity of the measurements, and it would appear that the range 35.5 degrees C to 37.2 degrees C was the best range to measure pyrexia in the age group one to 12 years. The 9-minute measurement then had the highest sensitivity. However, the specificity of measurement in this range was lower. The conclusion was drawn that axillary temperature measurement is an acceptable method, with certain reservations, to use as screening method for pyrexia in emergency divisions or clinics.

Age Factors↗
PubMed1999

Dietary intake of Indians living in the metropolitan area of Durban.

OBJECTIVE: To report on energy and nutrient intakes, as a risk factor for coronary heart disease in Indian South Africans. DESIGN: Cross-sectional dietary study as part of a coronary heart disease survey. SETTING: Metropolitan area of Durban, South Africa. SUBJECTS: Free-living Indian men (n = 406) and women (n = 370) 15-69 years of age. METHODOLOGY: Dietary data were collected by three interviewers using a 24-h dietary recall and expressed as median intakes of macronutrients. RESULTS: Results reported a low energy intake and the percentage of energy derived from total fat varied between 32.3 and 34.9% in men and between 33.1 and 36.1% in women. The energy intake to basal metabolic rate (EI:BMR) ratios were low for all age groups suggesting potential under-reporting. Intake of polyunsaturated fatty acids was high, more than 10% of energy, with a median polyunsaturated to saturated fatty acid ratio (P:S ratio) that varied between 1.38 and 1.96 for the various age and sex groups. Dietary cholesterol varied between 66 and 117 mg per 4.2 MJ in men and between 76 and 109 mg per 4.2 MJ in women. Dietary fibre intakes were low and varied between 8.0 and 11.0 g per 4.2 MJ in men and between 7.6 and 9.6 g per 4.2 MJ in women. CONCLUSIONS: The dietary P: S ratios were high and the effect of such a high P:S ratio on the oxidation of low density lipoprotein in this population, with a high prevalence of coronary heart disease (CHD), should be investigated as a possible risk factor for CHD.

Adolescent↗
PubMed1998

Correlation among total lymphocyte count, absolute CD4+ count, and CD4+ percentage in a group of HIV-1-infected South African patients.

Depletion of CD4+ T cells is one of the hallmarks of progression of HIV-1 infection. However, measurement of the CD4+ T-cell count is expensive and often unavailable in less developed areas. Previous studies have suggested that the total lymphocyte count (TLC) can be used to predict a low absolute CD4+ T-cell count. To determine the relationship between TLC and CD4+ T-cell count in HIV-1-infected South African patients, 2777 HIV-1-seropositive patients visiting the Immunology clinic at the Pelonomi Hospital in Bloemfontein, South Africa from April 1991 to April 1997 were included in the study. In total, 3237 observations were used to determine sensitivity, specificity, and likelihood ratios, with 95% confidence intervals, of various cutpoints of the TLC to predict an absolute CD4+ T-cell count of <200 cells/mm3, CD4+ percentage <20%, and CD4+ percentage <15%. Spearman rank correlations were calculated between TLC and CD4+ T cells, CD4+ percentage and CD8+ T cells, as well as between CD4+ and CD8+ T cells. Results demonstrated that a TLC of 2 x 10(9)/L or less had a sensitivity of 90.3% to detect patients with a CD4+ T-cell count of <200 cells/mm3, but a specificity of only 53.7%. When the TLC cutoff value was lowered, specificity increased but sensitivity decreased. For the observations as a group, a correlation (r = 0.704) between CD4+ T-cell count and TLC was demonstrated, but if the patients were divided into three groups according to their CD4+ T-cell count, this correlation weakened considerably. Therefore, although TLC shows a correlation with CD4+ T-cell count, it is not a good predictor of the CD4+ T-cell count in this population and should preferably not be used in the clinical care of HIV/AIDS patients.

Adolescent↗
PubMed1998

Detection of Mycobacterium tuberculosis in serum samples using the polymerase chain reaction.

Conventional methods for the diagnosis of Mycobacterium tuberculosis infections have serious limitations. To determine whether amplification of M. tuberculosis DNA in serum by the polymerase chain reaction (PCR) might be a useful additional diagnostic tool, we tested 329 clinical specimens using primers specific for the IS6110 insertion sequence of the M. tuberculosis complex. The samples consisted of 30 serum samples from healthy controls, 114 serum samples from patients with diagnoses other than tuberculosis (including immunosuppressive disorders), 59 samples from patients with a clinical picture suggestive of tuberculosis, and 78 serum samples from patients with proven M. tuberculosis infection. Both serum, and representative samples from anatomical regions suspected of being infected, were collected from a further 48 patients for comparison with serum PCR. Serum PCR identified 72/78 (92%; 95% confidence interval CI: 84%-97%) patients with proven tuberculosis, and 49/59 (83%; 95% CI: 71%-92%) patients with suspected tuberculosis. In the group of patients with other diagnoses, 30/114 (26%; 95% CI: 18%-34%) tested positive, while none of the specimens from the healthy control group were positive (95% CI: 0%-12%). Serum PCR results also compared favourably with other clinical specimens obtained from the same patient. Serum PCR can, therefore, be a useful additional technique for the early diagnosis of M. tuberculosis infection, but it does not necessarily indicate active infection.

DNA Primers↗
PubMed1998

Chronic lymphocytic leukaemia in the Bloemfontein academic hospitals.

OBJECTIVE: To study the clinical presentation, treatment and outcome of patients diagnosed with chronic lymphocytic leukaemia (CLL) in the Bloemfontein academic hospitals during the past 21 years. DESIGN: Descriptive, retrospective study of clinical records of all CLL patients diagnosed at the Haematology clinics of the Universitas and Pelonomi Hospitals in Bloemfontein from 1975 to 1996. METHODS: Age, sex and race distribution of CLL patients were analysed. The peripheral blood, bone marrow, clinical presentation and stage at time of diagnosis, were studied. Treatment modalities, response to treatment and survival of patients were also analysed. Categorical variables were summarised by frequencies and percentages, and numerical variables by means of percentiles. Subgroup comparisons were done by 95% confidence intervals (CI) for differences in percentages, medians or means. RESULTS: A total of 185 CLL patients were studied. There were more males (62.7%) than females and the mean age of the patients was 63 years (19 to 98 years). Eighty six percent of the patients were older than 50 years. Racial distribution was as follow: 106 White, 77 Black and two patients of mixed race. Black patients more often presented with advanced disease and higher lymphocyte counts. A response to therapy was noted for 118 (82.5%) of the 143 patients who received treatment. A complete remission or partial response was noted for 38 (32.2%) of the patients. CONCLUSIONS: The presentation of CLL in the Bloemfontein academic hospitals is similar to what is seen world-wide. This is the first study describing CLL in a large number of Black patients and demonstrates that although Black patients presented more often at a younger age and had high risk disease, their clinical course and progression according to stage, also correlated with what is described in the literature.

Adult↗