Biomedical subjects

S Hennings

Publications and source records attributed to S Hennings.

6 recordsLinked to original sources

PubMed2001

Low faecal elastase 1 concentrations in type 2 diabetes mellitus.

BACKGROUND: Previous studies have suggested an association between impaired pancreatic exocrine function and diabetes, but the evidence is weak because the invasive nature of the tests used to define exocrine function has led to small studies on selected patients. The availability of faecal elastase 1 as a non-invasive test has aided the detection of impaired exocrine function in population studies. We describe the association between levels of faecal elastase 1 and Type 2 diabetes. METHODS: 544 Type 2 diabetic patients (age: 63 +/- 8 years) were randomly selected from local diabetes registers in Cambridgeshire, UK and individually matched for age, sex and practice to 544 controls in whom diabetes was excluded by HbA1c measurement. RESULTS: Faecal elastase 1 concentrations were significantly lower in cases than controls (median: cases 308 microg/g; controls 418 microg/g; P < 0.01). Low levels of faecal elastase 1 (< 100 microg/g) were found in 11.9% of cases and 3.7% of controls (age-sex-adjusted odds ratio; 95% CI: 3.6; 2.2-6.2). After adjustment for potential confounding factors, the OR was 4.5 (2.6-8.3). Among patients with diabetes, poor glycaemic control (HbA1c > or = 7%) was associated with a higher risk of low elastase 1 level (OR 5.6; 1.5-37). No significant association was found with diabetes duration, peripheral neuropathy, alcohol intake, or prior gastrointestinal diseases. CONCLUSIONS: Faecal elastase 1 concentrations are lower in Type 2 diabetic patients than in non-diabetic controls, suggesting the co-existence of diabetes and impaired pancreatic exocrine function. Among the diabetic patients, the risk of having low elastase 1 levels was associated with glycaemic control.

Aged↗

PubMed2001

The effect of the Gly16Arg polymorphism of the beta(2)-adrenergic receptor gene on plasma free fatty acid levels is modulated by physical activity.

The lipolytic effects of catecholamines are mediated through members of the beta(2)-adrenergic receptor (BAR-2) family. Previous studies have suggested that genetic variants in the BAR-2 gene may be associated with obesity in some populations. To our knowledge, no studies have directly examined the effects of this polymorphism on circulating nonesterified fatty acid (NEFA) levels. To explore this issue further, a cohort of 604 Caucasian individuals (aged 40-65 yr) was genotyped for a common polymorphism in the BAR-2 gene (Gly16Arg), and the relationships between genotype, body mass index (BMI), NEFA, and lipid levels were examined. Women bearing the Arg16 allele had higher BMI values (P < 0.01) than Gly16Gly women. Women carriers of the Arg16Arg genotype had lower fasting plasma NEFAs (P < 0.01) and greater suppression of NEFAs (P < 0.01) after an oral glucose load than women bearing the Gly16 allele. In multivariate analysis after adjustment for age, sex, and smoking status, the interaction between the BAR-2 genotype and BMI in determining fasting NEFA concentrations was statistically significant (P < 0.05). The availability of objective measures of total energy expenditure in this population permitted the further examination of interactions, particularly that between genotype and physical activity. In the population as a whole, after adjustment for confounding by age, smoking, and BMI, the effect of the Arg16Arg genotype on the suppression of NEFA levels was modified by physical activity level (P for interaction <0.05). These data suggest the existence in this population of a gene-physical activity interaction on NEFA levels.

Adult↗

PubMed2000

Supratentorial primitive neuroectodermal tumours: diffusion-weighted MRI.

We report the clinical and pathological findings of supratentorial primitive neuroectodermal tumours (PNETs). These are rare, poorly differentiated, highly malignant neoplasms occurring primarily in young individuals. They frequently show dissemination to the spinal cord and sometimes also beyond neuraxis. Preoperative radiological diagnosis is difficult, due to the nonspecific CT and MRI characteristics. Our findings indicate that diffusion-weighted imaging (DWI) can be used to show the solid portion of the tumour preoperatively and to monitor postsurgical recovery. We describe the MRI findings in three patients with histologically confirmed supratentorial PNET, focussing on the role of DWI for improving the specificity of radiological diagnosis.

Child↗

PubMed2000

Quantifying the association between habitual energy expenditure and blood pressure.

BACKGROUND: Previous studies have demonstrated an association between physical inactivity and hypertension, but the methods used to assess activity have been subjective and imprecise. Recently methods have become available allowing measurement of energy expenditure in free-living populations. Our aim was to employ these methods to assess the independent association between energy expenditure, cardio-respiratory fitness and blood pressure. METHODS: In a cross-sectional study of 775 people (45-70 years) participating in a continuing population-based cohort study, energy expenditure was assessed by 4 days of heart rate monitoring with individual calibration of the relationship between heart rate and energy expenditure, a method validated against doubly-labelled water and whole body calorimetry. Cardio-respiratory fitness was assessed in a sub-maximal test. To adjust for measurement error in the assessment of usual energy expenditure and fitness, 190 subjects repeated both tests on three further occasions at 4-monthly intervals. RESULTS: A highly significant linear trend in blood pressure was found across quintiles of the physical activity level, the ratio of total energy expenditure to basal metabolic rate. The differences in the mean systolic/diastolic blood pressure between the top and bottom quintile was 6.3/4.4 mmHg in men and 10.7/5.9 mmHg in women. These effects were independent of obesity and cardio-respiratory fitness. Correction for measurement error suggests that the true underlying relationship between usual energy expenditure and blood pressure is stronger still. CONCLUSIONS: These findings are compatible with a strong association between usual energy expenditure and blood pressure and support public health strategies aimed at increasing overall energy expenditure.

Aged↗

PubMed1998

Purging and haemopoietic progenitor cell selection by CD34+ cell separation.

Tumour cell contamination of autologous peripheral blood stem cell samples (PBSC) and bone marrow (BM) is frequent. Enrichment of CD34+ stem cells is a promising approach to purging tumour cells from autografts without damaging progenitor cells. Breast cancer cells were seeded (10(-3)-10(-7)) into mononuclear cells from G-CSF-mobilised PBSC and BM harvests from patients without breast cancer. CD34+ cells were enriched from mixtures either by immunomagnetic separation (Isolex-50, and MiniMACS) or by biotin-streptavidin immunoaffinity columns (Ceprate-LC). CD34+ cell fractions were determined by FACS, cancer cells were detected immunocytochemically with an anti-pancytokeratin antibody. The CD34+ cells were enriched with a median purity of 92.2% (43.5-96.1) (n = 17) (Isolex-50), 96.5% (66.6-99.2) (n = 17) (MiniMACS) and 77.9% (31.4-93.6) (n = 15) (Ceprate-LC) from PBSC and BM harvests. The percentages of median recovery of CD34+ cells were 30.8% (18.6-71.8) (Isolex-50), 69.9% (39.1-100) (MiniMACS) and 42.9% (23.7-100) (Ceprate-LC). The median tumour cell reductions in log steps were 3.7 (2.9-4.3) (n = 13) (Isolex-50), 3.5 (2.6-4.3) (n = 13) (MiniMACS) and 1.5 (0.9-2.9) (n = 17) (Ceprate-LC). Results were compared statistically by univariate analysis. Purity was significantly (P < 0.05) better after MiniMACS selection. Recovery rates were significantly different between all devices tested. Tumour cell purging was superior after immunomagnetic separation (P < 0.001). Tumour cell purging is a main objective of CD34+ selection in the autologous setting. Our in vitro data clearly indicate that immunomagnetic separation is more efficient in the prevention of accidental reinfusion of contaminating tumour cells compared to immunoaffinity. However, it is not yet known if the same results can be obtained with fresh contaminating tumour cells.

Antigens, CD34↗

PubMed1996

Detection of cancer cells in peripheral blood stem cells of women with breast cancer by RT-PCR and cell culture.

The benefit of high-dose therapy and blood stem cell reinfusion for women with high-risk breast cancer is currently under investigation. Contaminations of autologous blood stem cells with cancer cells have been described. Cancer micrometastases may be detected by immunocytochemistry, culture techniques and cytokeratin-19 mRNA reverse transcriptase PCR. Women with breast cancer received adjuvant HD-CTM with peripheral blood stem cell (PBSC) support after surgical therapy and 4 cycles conventional chemotherapy. Peripheral blood stem cells were mobilised by G-CsF and harvested after the third or fourth cycle of standard therapy. Aliquots of PBSC-collections (10(7)-2*10(7) cells) were subjected to CK19-mRNA reverse transcriptase PCR. RNA was extracted by standard methods and reverse transcription was performed with MMV-RT. Integrity of RNA was checked by coamplification of housekeeping sequences. Aliquots of the RT-mix were subjected to PCR-amplification with outer and inner primer pairs, subsequently. A second aliquot of 2*10(7) cells was cultured over 42 days in liquid culture. Cytospins were prepared weekly from cultured cells and evaluated by light microscopy with or without prior immunocytochemistry. Ten leukaphereses from 6 women were available for PCR-analysis and cell culture. Six leukaphereses were negative for CK19-mRNA and for detection of cancer cells by culture technique, two samples were positive for CK19-mRNA and culturally enriched cells and two samples were positive for CK19-mRNA and negative for cultured cancer cells. No sample was positive for cultured cells and negative for CK19-mRNA. Overall, the results corresponded in 80%. Two sensitive techniques for the detection of cancer micrometastases were applied to aliquots from 10 leukaphereses of six breast cancer patients with corresponding results in 80%. PCR-mediated detection of cancer cells was confirmed by culture technique and light microscopy, however, further comparison of CK19-PCR with standard techniques like cell culture and immunocytochemistry is still necessary.

Breast Neoplasms↗