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PubMed2006

Mapping indicators of sexually transmitted infection services in the South African public health sector.

BACKGROUND: Prevention and early treatment of sexually transmitted infections (STIs) is a high public health priority in South Africa. In 2002 a national survey of public health care (PHC) facilities was conducted to develop measurable indicators for monitoring and evaluation of the National STI programme. In this paper we present maps of key indicators obtained from the survey, and discuss their programmatic implications. We also address some methodological issues that arise in the context of producing appropriate maps. METHODS: A national sample, stratified by subdistrict/municipality, of 962 PHC facilities was randomly selected. In each facility the senior nurse was telephonically contacted and interviewed to answer questions related to the implementation of STI prevention and management from a structured questionnaire. Responses were validated through a second phone call, and inconsistencies recorded. The following key variables were mapped: stock-outs of drugs and condoms, knowledge of correct treatment procedures, consistent record keeping, number of STI clients seen per month per 1000 adult population, number of condoms distributed per adult male, and number of trained nurses per 1000 population. Using conditional autoregressive models and Markov Chain Monte Carlo (MCMC) simulation, smoothed subdistrict level clinic responses were computed and 95% confidence limits estimated. RESULTS AND DISCUSSION: Drug stock-outs were reported by 13% [95% CI 10-15%] and condom stock-outs were reported by 4% [95% CI 2-5%] of facilities. Underlying geographical patterns of risk were more clearly observed when maps had been smoothed and were not dominated by sampling error. Smoothed maps show that there is a finite, low risk of drug stock-outs in all areas with higher risk regions more clearly identified. The maps of indicators of STI services at PHC facilities show that there are important differences in quality of service within South Africa and underscore the usefulness of facility level routine data both for local programme monitoring and planning and for providing a national "bird's eye view" of programme performance.

Adult↗

PubMed2004

Comparison of two methods for evaluating bone marrow metastasis of neuroblastoma: Reverse transcription-polymerase chain reaction for tyrosine hydroxylase and magnetic resonance imaging.

BACKGROUND: The presence of bone marrow (BM) metastasis and circulating tumor cells in patients with neuroblastoma is a significant prognostic factor at diagnosis and might antedate detection of a relapse by other diagnostic studies. In this study, the clinical value of reverse transcription-polymerase chain reaction (RT-PCR) to amplify mRNA for tyrosine hydroxylase (TH) and magnetic resonance imaging (MRI) during the clinical course of patients with advanced neuroblastoma, was evaluated. METHODS: Four patients with Stage 1, 4 or 4S neuroblastoma, were studied. BM and peripheral blood (PB), including peripheral blood stem cell (PBSC), samples were examined for TH mRNA using RT-PCR. Concurrently, MRI detection of BM metastasis was used. RESULTS: In all cases, except one that had no evidence of BM invasion, TH mRNA in BM and PB at diagnosis were positive, and TH mRNA at diagnosis disappeared after chemotherapy. In two cases, although involvement in the neurocentrum BM was detected by MRI, TH mRNA in the iliac crest BM was negative. The pathological area still remained on MRI after intensive therapy. CONCLUSION: RT-PCR for TH mRNA might be the most sensitive method for the detection of occult neuroblastoma cells in BM and PB. However, because invasion of the BM by neuroblastoma may have a focal distribution, sampling errors can occur. Therefore, not only RT-PCR but also MRI, need to be used to rule out marrow involvement, especially at diagnosis and BM relapse.

Adolescent↗

PubMed1989

Androgen and oestrogen receptor status in benign and neoplastic prostate disease. Study of prevalence and influence on time to progression and survival in prostate cancer treated by hormone manipulation.

TUR chips from 89 men were analysed prospectively for androgen and oestrogen nuclear and cytoplasmic receptors (ANR, ACR, ONR, OCR). Patients were selected on the basis of suspicion of neoplastic change on clinical feel of the prostate. A control group of benign cases was also collected prospectively. Histological examination showed that 46 patients had prostatic carcinoma and 43 had benign prostatic hyperplasia. No difference was found between the 2 groups in terms of prevalence of any of the receptors or in levels of receptor in those who were positive. The patients with neoplastic changes were followed up for a median of 53 months (range 47-64). No significant effect on duration of survival was noted with any of the receptor variables but there was a beneficial association between cytoplasmic oestrogen receptor positivity and progression-free interval. Patients with T category 3 or 4 had a significantly higher chance of being ANR positive than those of lower T category and this may reflect sampling error. There appears to be some evidence to suggest that cytosol oestrogen receptor positivity has a prognostic role in prostate cancer, in terms of time to progression on hormone therapy. Receptor status did not influence survival.

Aged↗

PubMed1993

Ploidy and prognosis in renal carcinoma.

The value of tumour ploidy status as a prognostic indicator in renal carcinoma is disputed. In this retrospective study the DNA content of 90 primary and 10 secondary renal cell carcinomas was measured using flow cytometry. Data on recurrence and survival were available in all cases. Tumours were staged according to the TNM system and histological grade was based on nuclear morphology. Formalin-fixed, paraffin-embedded material was processed using standard techniques. Multiple samples were examined in 19 cases. Of the primary tumours, 52 were diploid, 24 were aneuploid and 6 were tetraploid; 8 patients had uninterpretable histograms. Ploidy of the secondary tumours was similar to that of their respective primaries. Aneuploidy correlated with higher grade but not with TNM category and, although associated with an increased risk of death, did not provide independent prognostic information. Heterogeneity of ploidy was found in 6 of the 19 cases where more than 1 sample was assessed. It was concluded that tumour DNA content in renal carcinoma is weakly linked to outcome, is subject to sample error and does not provide accurate prognostic information as a single independent variable.

Adult↗

PubMed1994

Rapid processing in the management of prostatic cancer.

OBJECTIVE: To carry out rapid histological processing of prostatic biopsies for the management of patients who present with urinary retention or other urological problems, or with a suspected diagnosis of prostatic cancer. PATIENTS AND METHODS: Biopsies were taken from each of 26 patients who presented with urinary retention or other urological problems, or with a suspected diagnosis of prostatic cancer. The biopsies were processed in a Shandon Hypercenter using a 3-hour programme and were stained on a Shandon Linistainer automatic staining machine. The slides were reviewed both immediately and at weekly histopathology audit meetings. RESULTS: Results were available within 4 h of receipt of the specimen in the laboratory. One false negative, due to a sampling error at the time of biopsy, was identified. CONCLUSION: We believe that this facility is of benefit to both surgeon and patient and should be more widely available.

Biopsy, Needle↗

PubMed1994

Immunohistological expression of p53 in primary pT1 transitional cell bladder cancer in relation to tumour progression.

OBJECTIVE: To determine whether p53 expression is a marker of tumour progression in superficially invasive (pT1) transitional cell carcinoma of the bladder. PATIENTS AND METHODS: The immunohistochemical status of the p53 protein in 28 pT1 primary bladder cancers was determined on frozen tissue and archival paraffin block sections using three primary antibodies (CM-1, PAB1801 and D07). The findings were compared with the patients' progress. All the patients, except for those who died during the course of the study, were followed up by check cystoscopy for a minimum of 2 years. RESULTS: Immediately adjacent frozen sections stained identically in 10 of 16 cases for CM-1 and PAB1801. For paraffin sections, identical staining patterns were seen for PAB1801 and D07 in 21 of 26 sections. However, inter- and intra-tumour staining for p53 was very variable, even with the same antibody. The heterogeneity of p53 positive cell distribution in the tumours indicates potential for significant sampling errors if random sections are chosen as representative of p53 status. CONCLUSION: The p53 status of the primary tumours did not relate to patient outcome. The results obtained do not support the use of immunohistological p53 expression as a discriminating prognostic indicator in pT1 transitional cell carcinoma of the bladder.

Biomarkers, Tumor↗

PubMed2005

Association between MspI polymorphism of the APO AI gene and Type 2 diabetes mellitus.

AIMS: Genes of the Apo AI/CIII/AIV cluster on chromosome 11 have been related to plasma lipid patterns. The close relationship between carbohydrate metabolism and lipid metabolism warrants investigation of the association between this cluster and Type 2 diabetes mellitus. We therefore examined the possible association between polymorphisms of this cluster and Type 2 diabetes mellitus as part of a study of the prevalence of diabetes and the metabolic syndrome in southern Spain. METHODS: A total of 1224 persons were selected randomly from the town of Pizarra in the province of Malaga, southern Spain. The sample errors for the prevalence of Type 2 diabetes mellitus and the three polymorphisms studied were all < or = 4%. All subjects underwent phenotyping after an oral glucose tolerance test (75 g) (WHO 1998 criteria) and the XmnI and MspI polymorphisms of Apo AI and the SstI polymorphism of Apo CIII were genotyped. RESULTS: Those subjects with the mutated AA genotype of the MspI polymorphism (-75 G-->A) of Apo AI had a greater risk of impaired glucose tolerance [odds ratio (OR) = 1.95, CI = 1.02-3.8, P = 0.05], Type 2 diabetes mellitus, both known (OR = 7.38, CI = 1.3-39.7, P = 0.02) and unknown (OR = 3.7, CI = 1.4-9.9, P = 0.009). This risk was independent of age, sex, obesity, triglyceride level, HDL cholesterol and pattern of insulin resistance. CONCLUSIONS: Pending confirmation in prospective studies, the AA genotype of the MspI polymorphism of the Apo AI gene, within the Apo A-I/C-III/A-IV cluster, seems to be a risk factor for Type 2 diabetes mellitus.

Adult↗

PubMed2003

Comparison of genotyping of Helicobacter pylori cagA and vacA virulence genes from gastric biopsies and stool specimens.

BACKGROUND: We compared results of genotyping of Helicobacter pylori cagA and vacA virulence genes in DNA from gastric biopsies, both paraffin-embedded and frozen, and from stool samples, in order to evaluate the comparative sensitivity of the stool assay. METHODS: Genomic DNA from paraffin-embedded biopsies, unfixed frozen biopsies, and stool samples of the same 20 patients was amplified for the cagA gene, an empty site (which provides a positive signal for cagA negative strains) and for the s and m alleles of the vacA gene. Composite genotypes were determined by combining data from analysis of all three materials. RESULTS: Analysis of none of the materials taken singly showed all of the genotypes revealed by all three materials taken together, probably because of sampling error. Analysis of paraffin biopsies revealed 83.5%, that of frozen biopsies revealed 74.7% and that of stools revealed 75.9% of the genotypes. There was no significant difference in the percentage of the H. pylori genotypes identified from the three materials. Analysis of combinations of frozen biopsies and stools revealed 89.9% of the composite genotypes, and that of paraffin biopsies and stools revealed 96.2% of the composite genotypes. Evidence of multiple genotypes was found in 10 of 20 (50%) of the cases. CONCLUSIONS: Any one of the investigated biological materials can be used for detection of cagA and vacA genes, but no single assay provided a complete genotype. The use of a combination of two materials may generate a more accurate representation of H. pylori genotypes in each individual.

Adult↗

PubMed2000

The role of intracranial electrode reevaluation in epilepsy patients after failed initial invasive monitoring.

PURPOSE: Intracranial electrode recording often provides localization of the site of seizure onset to allow epilepsy surgery. In patients whose invasive evaluation fails to localize seizure origin, the utility of further invasive monitoring is unknown. This study was undertaken to explore the hypothesis that a second intracranial investigation is selected patients warrants consideration and can lead to successful epilepsy surgery. METHODS: A series of 110 consecutive patients with partial epilepsy who had undergone intracranial electrode evaluation (by subdural strip, subdural grid, and/or depth electrodes) between February 1992 and October 1998 was retrospectively analyzed. Of these, failed localization of seizure origin was thought to be due to sampling error in 13 patients. Nine of these 13 patients underwent a second intracranial investigation. RESULTS: Reevaluation with intracranial electrodes resulted in satisfactory seizure-onset localization in seven of nine patients, and these seven had epilepsy surgery. Three frontal, two temporal, and one occipital resection as well as one multiple subpial transection were performed. Six patients have become seizure free, and one was not significantly improved. The mean follow-up is 2.8 years. There was no permanent morbidity. CONCLUSIONS: In selected patients in whom invasive monitoring fails to identify the site of seizure origin, reinvestigation with intracranial electrodes can achieve localization of the region of seizure onset and allow successful surgical treatment.

Adolescent↗

PubMedDate not supplied

The accuracy of intraoperative diagnoses based on examination of frozen sections. A prospective comparison with paraffin-embedded sections.

The accuracy of diagnoses based on examination of frozen sections was determined by comparing the results to those obtained by examination of tissues prepared using conventional methods (formalin fixation, paraffin-embedded tissue). One hundred ninety-four specimens were examined using the frozen section technique; 37 were examined to confirm a tentative diagnosis or to document lymph node metastasis and the remainder were examined to diagnose an unknown pathologic process. Of the 194 specimens examined, an accurate, specific diagnosis was obtained in 161 (83%); in 19 (10%), the pathologic process was correctly identified, but a specific diagnosis was not obtained; and in 2 (1%) the diagnosis was deferred. The remaining 12 (6%) were incorrectly diagnosed by the frozen section technique. When the number of specimens in which a specific diagnosis was obtained was combined with the number of specimens in which the pathologic process was correctly identified, the overall accuracy rate of the frozen section technique was 93%. There was no difference in the accuracy of the frozen section technique based on the reason for submission of the sample, source of tissue submitted, or the type of pathologic process (i.e., inflammatory or neoplastic). Of the 12 incorrect diagnoses, 4 (33%) were because of sampling errors and 8 (67%) were caused by interpretation errors.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2006

Consumer-phase Salmonella enterica serovar enteritidis risk assessment for egg-containing food products.

We describe a one-dimensional probabilistic model of the role of domestic food handling behaviors on salmonellosis risk associated with the consumption of eggs and egg-containing foods. Six categories of egg-containing foods were defined based on the amount of egg contained in the food, whether eggs are pooled, and the degree of cooking practiced by consumers. We used bootstrap simulation to quantify uncertainty in risk estimates due to sampling error, and sensitivity analysis to identify key sources of variability and uncertainty in the model. Because of typical model characteristics such as nonlinearity, interaction between inputs, thresholds, and saturation points, Sobol's method, a novel sensitivity analysis approach, was used to identify key sources of variability. Based on the mean probability of illness, examples of foods from the food categories ranked from most to least risk of illness were: (1) home-made salad dressings/ice cream; (2) fried eggs/boiled eggs; (3) omelettes; and (4) baked foods/breads. For food categories that may include uncooked eggs (e.g., home-made salad dressings/ice cream), consumer handling conditions such as storage time and temperature after food preparation were the key sources of variability. In contrast, for food categories associated with undercooked eggs (e.g., fried/soft-boiled eggs), the initial level of Salmonella contamination and the log10 reduction due to cooking were the key sources of variability. Important sources of uncertainty varied with both the risk percentile and the food category under consideration. This work adds to previous risk assessments focused on egg production and storage practices, and provides a science-based approach to inform consumer risk communications regarding safe egg handling practices.

Bacteriophage Typing↗

PubMed2006

Proper assessment of the JFK assassination bullet lead evidence from metallurgical and statistical perspectives.

The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano (MC), 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in MC bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.

Famous Persons↗

PubMed2004

The presence and mucin histochemistry of cardiac type mucosa at the esophagogastric junction.

OBJECTIVES: Traditionally, the gastric cardia has been described as a native part of the stomach connecting to the esophagus. In recent literature, however, it is suggested that the cardia is an acquired lesion that develops due to gastroesophageal reflux disease. As a contribution to this debate, we evaluated the presence of cardiac mucosa at the esophagogastric junction (EGJ) in a random group of patients who presented at our endoscopy unit. METHODS: In 253 unselected patients, biopsies were taken from the EGJ. In order to prevent sampling error, we selected only those EGJ biopsies in which the squamocolumnar junction (SCJ) was present in the histological biopsy material. Fifty-five patients were excluded since the SCJ was located proximal to the EGJ in the esophagus. The type of columnar mucosa immediately distal to the SCJ, and its mucin histochemistry, were assessed. The columnar mucosa was categorized as purely cardiac, oxyntocardiac, or fundic mucosa. RESULTS: In 63 of the 198 patients, the SCJ was actually present in the EGJ biopsies. Purely cardiac mucosa was present in 39 (62%) biopsies and oxyntocardiac mucosa was present in 24 (38%) biopsies. Fundic mucosa was not seen directly adjacent to squamous epithelium. Acid mucins were present in 23 (37%) patients and they correlated with histological esophagitis and presence of H. pylori in the cardia. CONCLUSIONS: Cardiac mucosa was uniformly present adjacent to the squamous epithelium at the EGJ. This argues against the hypothesis that the gastric cardia is an acquired metaplastic lesion. The presence of acid mucins was frequently observed and could be a pathological condition as it was associated with histological esophagitis and the presence of H. pylori in the cardia.

Adult↗

PubMed1998

Transient increases in colony counts observed in declining populations of Campylobacter jejuni held at low temperature.

Colony forming unit counts of Campylobacter jejuni were serially determined in a variety of microcosms in which growth was not expected. Unremitting decline in colony counts occurred in nutrient-free systems, however, transient increases were observed in human faecal emulsions and nutrient media on storage at between 1 and 25 degrees C. The phenomenon, which was more pronounced at lower temperatures, could not be attributed to sampling errors, cell clumping or the influence of minor fluctuations in experimental conditions. C. jejuni is capable of either growth at low temperatures or transition between temporarily nonculturable and culturable states.

Anti-Bacterial Agents↗

PubMed1986

Type III aminoterminal propeptide of procollagen in some haematological malignancies.

Marrow fibrosis is involved in some haematological malignancies. Either because of sampling errors, variations of focal distribution of fibrosis or the discomfort for patients of bone biopsies, conventional histology appears to be unsuitable for the follow-up of myelofibrosis. During collagen synthesis by marrow fibroblasts, the aminoterminal propeptide is removed from procollagen III and released in the serum. Thus, a sensitive radioimmunoassay of type III aminoterminal propeptide of procollagen (PC III) has been tested in myeloproliferative and lymphoproliferative disorders with a marked bone marrow fibrosis. In polycythaemia vera, PC III level was significantly increased as compared to controls and was related to marrow fibrosis of grade I. The more increased PC III values were observed in spent polycythaemia cases initially treated by phlebotomy alone. Follow-up showed a transformation into myeloid metaplasia. In contrast, PC III remained stable in patients treated with radiophosphorus 32P or hydroxyurea who did not transform. In myeloid metaplasia, results of PC III were significantly higher than in controls or polycythaemia vera cases. Myelofibrosis of recent onset (less than 2 years) gave higher values than chronic myelofibrosis. Increased PC III values were also emphasized in chronic myelocytic leukaemia, and in a few cases of refractory anaemia with excess of blasts, hairy cell leukaemia and chronic lymphocytic leukaemia.

Bone Diseases↗

PubMed1990

Sirius red histophotometry and spectrophotometry of sections in the assessment of the collagen content of liver tissue and its application in growing rat liver.

By means of staining with Sirius Red F3BA in a saturated picric acid solution, the collagen contents of rat livers with varying degrees of fibrosis have been measured quantitatively in fixed and sectioned material, using both histophotometry in situ and extraction of bound dye with colorimetric analysis. These findings have been correlated with chemical assays of the hydroxyproline content in homogenates from the same livers. It appears that a highly significant correlation exists between both section-based analysis methods and the hydroxyproline content, the Spearman-Rank correlation coefficients being virtually identical. For analysis of collagen accumulation in rat liver, both section-based methods seem to be useful and reliable, the extraction method giving the quickest results for large-scale screening, and the histophotometric method being more appropriate to take readings in selected areas. With human liver material, indications have been obtained for the existence of large sampling errors due to inhomogeneous distribution of collagen deposits. Using the extraction method, no significant changes could be observed in the volume density of collagen during postnatal growth from 1 week to 21 months in rat liver: only on the third day after birth was a higher value of collagen/total protein obtained, possibly due to a higher water content of the hepatocytes. Partial hepatectomy was found to have no influence at all on the collagen content of rat liver during the period of restorative growth or after it.

Animals↗

PubMed1987

Day-night differences in the number and structure of synaptic ribbons in chick pineal.

The objective of this study was to evaluate the effect of lighting (day-night) changes on pinealocyte synaptic ribbon shape (conformation) and numbers. Three-dimensional reconstruction analysis of pinealocyte basal processes revealed that 30% (6/20) of all ribbons from dark-adapted animals were either curved or split. Synaptic ribbons from light-adapted animals did not show this variant morphology; all were linear structures. An analysis of each section from each series, containing curved or split ribbons, revealed that 44% (16/36) of all ribbon profiles would yield inflated counts if used in random morphometric sampling protocols. Therefore, split and curved (variant) ribbon morphologies could result in an overestimation of synaptic ribbon populations of approximately 13% (0.44 X 30%) of dark-adapted samples. In spite of this potential sampling error, the fourfold increase in the number of synaptic ribbons observed during the dark phase of a light-dark cycle remains highly significant (P less than 0.0001).

Animals↗

PubMed1999

Cardiovascular disease risk factors and obesity of rural and urban elementary school children.

Previous studies on the influence of a rural/urban setting on the prevalence of cardiovascular disease risk factors in children have not sufficiently controlled for socioeconomic status, race, gender, and perhaps, may not have included a representative sample of rural and urban children. This study compared the cardiovascular disease risk factors and rate of obesity of children living in rural and urban settings. It also determined the magnitude of the effect of the rural/urban setting on cardiovascular disease risk factors and obesity when controlling for race, socioeconomic status, and gender. The subjects were 2,113 third- and fourth-grade children; 962 from an urban setting and 1,151 from a rural setting. Height, weight, skinfolds, resting blood pressure, and total cholesterol levels were measured. Aerobic power (pVO2max) was estimated from cycle ergometry. Physical activity and smoking history were obtained from a questionnaire. Clustering analyses using adjustment for sample error indicated that total cholesterol, blood pressure, smoking, and physical activity levels of rural and urban children were not different (P > 0.10); however, body mass index and sum of skinfolds was greater for rural youth (P < 0.004). Logistic regression indicated that rural children had a 54.7 percent increased risk of obesity (P = 0.0001). This study's results indicate that, in children, a rural setting is associated with obesity, but not with the major risk factors associated with cardiovascular disease.

Cardiovascular Diseases↗