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The article presents information on a study aimed at testing the hypothesis that bile acids (BA) are involved in acute bone suppression observed after a meal. The study was conducted in 10 healthy male volunteers. It was demonstrated that an association between glycine conjugated bile acids (GCBA) and parathyroid hormone (PTH) suppression after a meal.

Background: Obesity is associated with hypertension, but the exact mechanism is not fully understood. Bariatric surgery significantly decreases weight and blood pressure (BP). Low plasma nitric oxide (NO) and raised asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO, concentrations are associated with both obesity and hypertension. Correlations between the changes in these parameters were studied after bariatric surgery. Methods: Weight, BP, plasma ADMA and NO were measured in 29 obese patients (24 female, 5 male) before and six weeks after bariatric surgery. Results: Patients were 39.2 ± 1.2 (mean ± SEM) years old and weighed 126 ± 3 kg. Six weeks after the surgery, patients had lost 10 ± 0.7 kg (P < 0.0001) and mean arterial pressure (MAP) decreased by 11 ± 1.0 mmHg (P < 0.0001). The plasma ADMA concentration decreased by 24 ± 2% from 5 ± 0.4 to 4.0 ± 0.3 mmol/L (P < 0.0001). The plasma total nitrite concentration increased by 15 ± 1% from 51.4 ± 2.6 to 60 ± 3 mmol/L (P < 0.0001). The correlation between the decrease of ADMA and increase of NO subsequent to weight loss was significant (P < 0.0001). However, MAP was not correlated to the changes in ADMA or NO. Conclusions: After bariatric surgery, beneficial changes in BP, NO and ADMA occur, but our findings suggest that these BP changes are independent of changes in the NO-ADMA axis. Other causes for the changes in BP should therefore be considered. [ABSTRACT FROM AUTHOR]

Background: Adiponectin and leptin are adipose tissue-derived hormones, shown to have opposing associations with the metabolic syndrome and coronary heart disease (CHD). This study evaluated the association between the leptin/adiponectin ratio and the components of the metabolic syndrome in a cohort with CHD. Methods and results: This cross-sectional study included data from 105 subjects (men = 91), undergoing first-time elective coronary artery bypass grafting (CABG). Leptin and adiponectin concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Association was found between the leptin/adiponectin ratio and homeostatic model assessment (HOMA) (rs = 0.34, P = 0.0006), fasting insulin concentrations (rs = 0.37, P = 0.0001), fasting glucose concentrations (rs = 0.24, P = 0.01), systolic blood pressure (rs = 0.20, P = 0.05), diastolic blood pressure (rs = 0.24, P = 0.02), waist circumference (rs = 0.55, P, 0.0001), body mass index (BMI) (rs = 0.55, P< 0.0001) and waist/hip ratio (rs = 0.38, P = 0.0001). A significant difference was found in ratios between those with and without insulin resistance (HOMA . 3 and HOMA > 3) (P = 0.029) and those with and without metabolic syndrome, defined by the International Diabetes Federation, (P, 0.001). However, using receiver operating characteristic (ROC) analysis and assessment of area under curve (AUC), the leptin/adiponectin ratio did not perform significantly better than its components. Conclusion: In patients with severe CHD, the leptin/adiponectin ratio was not found to be a robust tool to distinguish patients with and without insulin resistance and those with and without the metabolic syndrome. [ABSTRACT FROM AUTHOR]

Insulin resistance occurs in pre-eclampsia, but the cause is unknown. Furthermore, it is uncertain whether women destined to develop pre-eclampsia have a pre-existing insulin resistance or whether it is acquired with the development of the disease, we carried out this study to test the hypotheses that the increase in insulin resistance associated with pre-eclampsia is related to higher levels of tumor necrosis factor (TNF)-α and that the increase in insulin resistance precedes the clinical onset of the disease. Fasting plasma samples were obtained from ten women who subsequently developed pre-eclampsia and ten normal pregnant controls at 16, 20, 24, 28, 32 and 36 weeks' gestation to measure circulating levels of insulin, glucose and TNF-α Fasting insulin resistance index (FIRI) was calculated from insulin and glucose concentrations. In the normal controls, fasting insulin and TNF-α levels, and FIRI increased with gestation, and these were significantly greater than baseline values from 24, 28 and 28 weeks, respectively. In the group of women who developed pre-eclampsia, plasma levels of insulin and the FIRI were significantly higher than baseline from 20 and 24 weeks, respectively, but both were significantly higher than in the control group at 32 and 36 weeks. The increase in TNF-α in the pre-eclampsia group was significantly greater than in normal pregnant controls (p <0.001). However, there was no significant association between TNF-α levels and FIRI in either normal pregnancy or pregnancies developing pre-eclampsia. These data suggest that insulin resistance in pre-eclampsia precedes the clinical onset of the disease, but that it is not related to elevated levels of TNF-α. [ABSTRACT FROM AUTHOR]

Background: Glycolysis is not completely or predictably inhibited by the glucose preservative currently in use, with glucose values falling by as much as 0.5 mmol/L during a 2-4-h period after sample collection. Immediate centrifugation of all samples is also impractical and therefore misdiagnosis of disease can occur, especially if more emphasis is being placed on fasting glucose for the diagnosis of diabetes. Methods: Glycolysis at room temperature was evaluated over time using glyceraldehyde alone as well as in conjunction with standard antiglycolytic agents. Results: Glyceraldehyde alone does not inhibit glycolysis completely. The combination of 11mmol/L glyceraldehyde, 119 mmol/L sodium fluoride and 21.7 mmol/L potassium oxalate gave the best antiglycolytic results. The glucose values measured in samples stored at room temperature for 48 h was no different from those measured in samples centrifuged immediately after venepuncture and this is clinically superior to conventionally used sodium fluoride and potassium oxalate. Conclusion: Plasma glucose concentrations obtained from blood collected into tubes containing glyceraldehyde, sodium fluoride and potassium oxalate will more closely reflect those of the patient at venepuncture. [ABSTRACT FROM AUTHOR]

Leptin is a metabolic regulator of the hypothalamic- pituitary-gonadal axis, and plays an important role in human reproduction. Its neuro-endocrine effects are mediated by interactions with receptors in the hypothalamus, where emotional drive is also controlled. We postulated that circulating leptin concentrations are increased in premenstrual syndrome (PMS), and that this may be associated with the psychological symptoms of the disease. We obtained fasting venous samples from 32 women with PMS and 28 women with asymptomatic menstrual cycles, matched for age, body mass index and menstrual cycle length. Leptin concentrations were measured by radioimmunoassay. Leptin concentrations increased significantly during the luteal phases of the menstrual cycles of the control and PMS groups as compared with the follicular phase, having excluded the 11 women with PMS and six controls found to be anovulatory on the basis of mid-luteal plasma progesterone concentrations from the analysis. A greater increase was observed in women with PMS than the controls (P: = 0.00006 and 0.003 respectively). Although leptin concentrations in the follicular and luteal phases were higher in PMS than the controls, the difference was only statistically significant between the follicular phases (P: = 0.001). There was no clear relationship between leptin and oestradiol or progesterone in this study. These findings suggest that leptin may play a role in the pathophysiology of the disease, and requires further evaluation. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate role of the feto-placental unit in the pregnancy-induced increase in maternal bone metabolism. To achieve this, circulating concentrations of carboxy terminal pro-peptide of type I pro-collagen (PICP, a marker of bone formation) and cross-linked carboxy terminal telopeptide of type I collagen (ICTP, a marker of bone resorption) were measured in three groups of pregnant women. Group 1 comprised 12 women with singleton pregnancies; group 2, nine women with twin pregnancies; and group 3, 19 women with multifetal pregnancies (> or =3 fetuses) before and after selective fetal reduction to twin pregnancies. Blood samples were obtained at 10-12 weeks gestation (groups 1-3, pre-fetal reduction in group 3) and 4 weeks and 8 weeks later (groups 2 and 3). Before fetal reduction there was a significant correlation between the number of fetuses and the concentrations of both PICP and ICTP (r = 0.503 and P = 0.001 and r = 0.573 and P < 0.001 respectively). The circulating concentrations of PICP and ICTP were significantly higher in the pre-reduction multifetal pregnancies than in the twin pregnancies (P < 0.001 and P = 0.0013 respectively). The circulating concentrations of ICTP in multifetal pregnancies fell by 4 weeks after fetal reduction to those observed in control twins. Concentrations of PICP were unaltered after fetal reduction. Higher order multiple pregnancies had the greatest decline in ICTP concentrations. These data suggest that the increased bone turnover observed in the multifetal pregnancies is due to a factor derived from the feto-placental unit and that this factor acts primarily to stimulate bone resorption. [ABSTRACT FROM AUTHOR]

Dexamethasone administration has marked effects on the growth hormone-insulin-like growth factor axis (GH-IGF) in animal and human studies. During pregnancy in the rat, it is associated with fetal growth restriction due to inhibition of IGF bioactivity. In the human only repeated dosages have been associated with fetal growth restriction. The aim of this study is to test the hypothesis that antenatal dexamethasone administration to pregnant women is associated with reduced activity of the GH-IGF axis. To achieve this blood samples were taken from 12 pregnant women pre- and at 24 h and 48 h after dexamethasone administration. In these samples GH, IGF-I, IGF bioactivity and IGF binding protein (IGFBP)-3 protease activity were measured. In view of the interaction between insulin and the GH-IGF axis, glucose and insulin concentrations were also measured. There were no significant differences between the concentrations of GH, IGF-I, IGF bioactivity and IGFBP-3 protease activity before and after dexamethasone. The concentrations of glucose and insulin were significantly higher at 24 h, but not 48 h post-dexamethasone. It is concluded that a single antenatal course of dexamethasone does not alter the GH-IGF-I axis in pregnant women at the time points studied. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether the current regimen of dexamethasone administration to induce fetal lung maturation affected the circulating concentrations of placental hormone. A standard regimen of dexamethasone that comprised two doses of 12-mg intramuscular injections, 12 h apart was administered to 12 pregnant women to promote fetal lung maturation in anticipation of premature delivery before 34 completed weeks of gestation. Blood samples were collected before starting the dexamethasone therapy, 24 h, and 48 h after completing therapy for the measurement of the plasma concentrations of human chorionic gonadotrophin (HCG), oestradiol and progesterone. There was a progressive fall in the plasma concentrations of HCG following dexamethasone therapy (P = 0.049 and P = 0.034, 24-h and 48-h post therapy respectively). There was an initial fall in the plasma concentrations of oestradiol after dexamethasone therapy (z = 3.059; P = 0.002, 24-h post therapy), which recovered by 48 h (P = 0.239). There was no difference between the plasma concentrations of progesterone at the three time points. The effect of dexamethasone on HCG concentrations suggests that it has a direct inhibitory effect on placental hormone synthesis or secretion. Further studies are needed to define the mechanism of action of dexamethasone on placental HCG production. [ABSTRACT FROM AUTHOR]

The synchronous relationship between oestrogen (ER) and progesterone (PgR) receptor status in primary tumours and their nodal metastases has been analysed in 26 patients. All patients with ER-negative primary tumours were found to have ER-negative axillary nodes but of those with ER-positive tumours only 65% had, correspondingly, all nodes ER-positive. The concentration of ER in the nodes was found to be significantly lower (P less than 0.001) than that in the primary tumour. PgR information was unobtainable in 3 patients. Of the remainder, 75% of those having PgR-negative tumours had all nodes PgR-negative but only 36% of those with PgR-positive tumours had all nodes PgR-positive. PgR levels were found to be generally lower in the axillary nodes but this did not reach statistical significance. The clinical relevance of these findings is discussed. [ABSTRACT FROM AUTHOR]

In a consecutive series of thirty-six male and female patients referred with severe acne, the effect of 3 months' treatment with placebo or spironolactone (50–200 mg daily) on sebum excretion and clinical and endocrine status was evaluated double-blind. Twenty-six patients completed the study. Abnonnal free androgen indices were found in 27% of the original nineteen female subjects. Spironolactone reduced sebum excretion in all female subjects, but there was no correlation between sebum response and androgen status. The clinical response was dose-dependent, with maximum subjective and objective benefit when spironolactone doses of 150–200 mg were used. [ABSTRACT FROM AUTHOR]

Presents several correspondence on medicine in Europe. Consequence of mastectomy; Importance of thyroxine in the suppression of thyroid stimulating hormone; Complication of perforated appendix.

The effect of graded exercise on the secretion of cortisol, testosterone, prolactin, growth hormone, thyroid stimulating hormone (TSH), luteinizing hormone and follicle stimulating hormone (FSH) is reported. While cortisol, prolactin, growth hormone and testosterone rise during the period of exercise, a rise in luteinizing hormone becomes evident only after rest. Levels of FSH and TSH remained unchanged. [ABSTRACT FROM PUBLISHER]

The reliability of an immunohistological method, applied to paraffin wax sections, was assessed for determination of oestrogen receptor content of biochemically oestrogen receptor negative breast carcinomata. Sixty consecutive tumours with oestrogen receptor concentrations of less than 10 fmol/mg cytosol protein, as estimated by dextran-coated charcoal biochemical assay, were examined. Paraffin wax sections were treated with DNAse before applying a peroxidase-anti-peroxidase method using ER-ICA monoclonal antibodies. Fifty one cases (85%) were negative, six (10%) weakly positive, and three (5%) were moderately positive. No strongly positive cases were seen. It is suggested that cases with weakly positive staining, especially when localised to a small area, should be regarded as negative. On the other hand, as the three moderately stained cases included two small tubular carcinomas and an invasive ductal carcinoma with high progesterone receptor concentrations, it is more likely that the biochemical assay in these cases represented false negative results due to sampling error or inclusion of fibrous or other non-neoplastic tissue in the assayed samples. It is concluded that the immunohistological method used here is fairly reliable and would be especially valuable for determination of oestrogen receptor content in small, mammographically detected tumours from which no tissue would be available for biochemical assay or frozen section examination. [ABSTRACT FROM PUBLISHER]