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Biomedical subjects

J H Barth

Publications and source records attributed to J H Barth.

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

Randomised controlled trial of primary school based intervention to reduce risk factors for obesity.

OBJECTIVE: To assess if a school based intervention was effective in reducing risk factors for obesity. DESIGN: Group randomised controlled trial. SETTING: 10 primary schools in Leeds. PARTICIPANTS: 634 children aged 7-11 years. INTERVENTION: Teacher training, modification of school meals, and the development of school action plans targeting the curriculum, physical education, tuck shops, and playground activities. MAIN OUTCOME MEASURES: Body mass index, diet, physical activity, and psychological state. RESULTS: Vegetable consumption by 24 hour recall was higher in children in the intervention group than the control group (weighted mean difference 0.3 portions/day, 95% confidence interval 0.2 to 0.4), representing a difference equivalent to 50% of baseline consumption. Fruit consumption was lower in obese children in the intervention group (-1.0, -1.8 to -0.2) than those in the control group. The three day diary showed higher consumption of high sugar foods (0.8, 0.1 to 1.6)) among overweight children in the intervention group than the control group. Sedentary behaviour was higher in overweight children in the intervention group (0.3, 0.0 to 0.7). Global self worth was higher in obese children in the intervention group (0.3, 0.3 to 0.6). There was no difference in body mass index, other psychological measures, or dieting behaviour between the groups. Focus groups indicated higher levels of self reported behaviour change, understanding, and knowledge among children who had received the intervention. CONCLUSION: Although it was successful in producing changes at school level, the programme had little effect on children's behaviour other than a modest increase in consumption of vegetables.

Body Mass Index↗
PubMed2001

Risk factors for coronary heart disease in obese non-diabetic subjects.

OBJECTIVE: To examine relationships between body mass index (BMI) and coronary risk factors in obese subjects presenting to a dedicated obesity clinic. STUDY DESIGN: Cross-sectional population survey from a single centre. SUBJECTS: Three hundred and eighty-six consecutive non-diabetic obese subjects (301 women, 85 men) attending an obesity clinic for the first time (mean BMI 43.3 kg/m(2); range 30.6-71.5), aged 17-69 y (mean 40.1). MEASUREMENTS: Height, weight, resting blood pressure, fasting plasma cholesterol, triglyceride, glucose and uric acid concentrations. RESULTS: All variables measured showed an increase with higher BMI (triglycerides, P=0.04; glucose, P=0.007; urate, P<0.001; systolic BP, P<0.001; diastolic BP, P<0.001) as measured by one-way ANOVA, except cholesterol concentration which showed no relationship with BMI. In comparison with the group of subjects with BMI 30-35 kg/m(2) mean values for all variables were higher in the more obese subjects. CONCLUSIONS: Non-diabetic subjects with BMI>35 kg/m(2) carry a burden of common coronary risk factors which appears to increase with greater obesity. The risk factor pattern observed echoes that described in insulin resistance syndromes. Plasma cholesterol concentration appears not to be related to BMI.

Adolescent↗
PubMed2001

Appropriate design of biochemistry request cards can promote the use of protocols and reduce unnecessary investigations.

Attempts to control laboratory workload in the past always proved to be short-lived. We designed a request card based on clinical conditions for a gynaecology out-patient clinic to help clinical staff to adhere to agreed investigation protocols. Each request card had a tick-box associated with a clinical condition. The tests performed for each condition were advertised on a poster in the clinic. The workload was assessed for a 2-year period before and after the introduction of these cards. The numbers of all endocrine tests, except progesterone and sex hormone binding globulin, fell by 19% (P<0.0001) whereas the clinical cases seen remained steady at 227 per month. This report demonstrates that agreed protocols can be implemented but that a persistent aide-mémoire is necessary.

Biomarkers, Tumor↗
PubMed2001

Endocrinology of gynaecomastia.

Gynaecomastia is the most common disorder of the male breast. It can occur at any age, and for this reason laboratory investigations may be requested by clinicians from many specialties. Gynaecomastia may occur transiently in neonates. It may also occur transiently during puberty, when it is common and generally benign. It must, however, be regarded as unusual in prepubertal children and all young and middle-aged men. Although iatrogenic and benign gynaecomastia are common in the elderly, further investigations may still be justified since breast cancer or other neoplasm must be ruled out. Biochemical investigations, when warranted, are aimed at establishing an underlying cause. Endocrine investigations might include serum oestradiol (or oestrone if available), testosterone, luteinizing hormone, sex-hormone-binding globulin, human chorionic gonadotrophin, prolactin and thyroid function tests. In this review, the source and role of oestrogens in men, the androgen oestrogen dynamics, the causes and clinical entities of gynaecomastia, and interpretation of laboratory tests are described.

Androgens↗
PubMed2000

The combined pituitary function test in children: an evaluation of the clinical usefulness of TRH and LHRH stimulation tests through a retrospective analysis of one hundred and twenty six cases.

OBJECTIVE: The combined pituitary function test is routinely used in the endocrine investigation of short children. The TRH and luteinising hormone-releasing hormone (LHRH) response tests have been shown to be of minimal value in adults. We have evaluated the clinical utility of these tests in the context of combined pituitary function testing in children. DESIGN: A retrospective analysis of basal hormone measurements and pituitary stimulation tests in relation to clinical assessment of pituitary function. PATIENTS: One hundred and twenty-six children, 82 boys and 44 girls, aged 2-17 years, who had undergone pituitary function testing were studied. RESULTS: The TSH response to TRH stimulation correlated directly with basal plasma TSH but not basal plasma total T4. In patients with an impaired response to stimulation, basal TSH concentrations were <2.0 mIU/l and significantly lower than in patients with a normal response (P < 0.0001). An impaired response to TRH stimulation had a positive predictive value of 0.43 and a negative predictive value of 0.90 for the diagnosis of hypopituitarism. A basal TSH concentration of <2.0 mIU/l had a positive predictive value of 0.22 and a negative predictive value of 0.92. A low basal T4 (normal range 60-140 nmol/l) in combination with an inappropriately low or normal basal TSH was always associated with a diagnosis of hypopituitarism. The responses of plasma LH and FSH to LHRH stimulation correlated directly with basal plasma LH and FSH concentrations. Basal gonadotrophin concentrations, basal sex hormone concentrations or response to LHRH stimulation could not distinguish patients with constitutional delay of growth and puberty from those with hypopituitarism. There was no apparent relationship between either basal gonadotrophin concentrations or response to LHRH stimulation and clinical assessment of pituitary function. In patients > or =13 years with constitutional delay of growth and puberty the median and interquartile ranges of basal LH and FSH were 1.4 IU/l (0.7-3.6) and 2.6 IU/l (2.2-5.2) respectively. The three hypopituitary patients in this study with chronological age > or =13 years had undetectable concentrations of both gonadotrophins. The response of LH and FSH to LHRH stimulation was significantly lower in patients > or =13 years with clinical hypopituitarism than in those with intact pituitary function (P <0.02). CONCLUSION: TRH and LHRH tests in children with short stature appear to have little value over and above the baseline hormone measurements. An abnormal response to hormone stimulation is not diagnostic of hypothalamic-pituitary disease. We have demonstrated that neither TRH nor LHRH stimulation tests should be routinely used in the investigation of children with short stature.

Adolescent↗
PubMed1998

The ratio of erythrocyte zinc-protoporphyrin to protoporphyrin IX in disease and its significance in the mechanism of lead toxicity on haem synthesis.

Protoporphyrin and zinc-protoporphyrin were measured in the erythrocytes of normal subjects, workers exposed to lead and patients with iron deficiency and erythropoietic protoporphyria (EPP). Results showed significantly higher levels of zinc-protoporphyrin in the lead-exposed workers (P < 0.0001), patients with iron deficiency (P < 0.0001) and EPP patients (P < 0.001) compared with normal subjects. The lead-exposed workers showed the highest levels of zinc-protoporphyrin, which were significantly greater than both the iron-deficient and EPP patients (P < 0.0001). They also showed a higher ratio of zinc-protoporphyrin to free protoporphyrin compared with normal subjects (P < 0.0001) but no significant difference in this ratio was found when compared with iron-deficient patients (P = 0.1). These results are discussed in light of the controversy concerning the mechanism of formation of zinc-protoporphyrin in lead exposure.

Adult↗
PubMed1997

Ovarian hyperthecosis, diabetes and hirsuties in post-menopausal women.

OBJECTIVE: We describe four patients with ovarian hyperthecosis and the effects of gonadotrophin releasing hormone on clinical and metabolic variables. DESIGN: Open out-patient study. PATIENTS: Four women presented with post-menopausal hirsuties. They had significant hair growth across the chest, upper back and shoulders. Three had histologically proven ovarian hyperthecosis and a fourth had large ovaries visualized on ultrasound. All four women had pronounced risk factors for vascular disease; hypertension, hyperlipidaemia and glucose intolerance, and three had already developed symptomatic vascular disease. RESULTS: Gonadotrophin releasing hormone agonist therapy resulted in significant reduction in plasma androgens and cosmetic reduction in hair growth but had no effect on hyperlipidaemia. CONCLUSION: The post-menopausal women described in this report were clinically considered to have hyperandrogenism due to the pathological pattern of marked body hair over the upper trunk. Treatment with GnRH was very effective at reducing the severity of the hirsuties. The post-menopausal women with hyperthecosis in this report had a high prevalence of cardiovascular disease. Since hyperandrogenism and insulin are considered risk factors for cardiovascular disease in premenopausal women with polycystic ovaries, we discuss the possible relationship between insulin and the post-menopausal ovary.

Aged↗
PubMed1997

Interassay differences in growth hormone measurement in acromegaly.

We measured plasma growth hormone concentrations by three different two-site immunometric assays (Pharmacia hGH RIA, IDS Gamma-BCT and Delfia 22 kDa hGH) to determine whether there are GH isoforms secreted by acromegalic patients that are under-recognized by some assays. There was a fairly good agreement between assays with the IDS Gamma-BCT and Delfia 22 kDa assays giving lower results than the Pharmacia IRMA. GH was measured on stored plasma samples from 24 patients with proven acromegaly. There was a consistent difference between the three assays of approximately 20% of the mean value for each patient.

Acromegaly↗