Serum prolactin in advanced chronic liver disease.

Hyperprolactinemia is a frequent endocrine disorder with well known harmful effects on the reproductive system and bone metabolism. Besides prolactinomas several drugs and disorders such as renal failure and hypothyroidism have been shown to cause hyperprolactinemia. Based on former studies, liver cirrhosis has also been suggested to cause hyperprolactinemia, while mechanisms have not been identified yet. In this study, we set out to investigate the prevalence and predictors of hyperprolactinemia in 178 patients with liver cirrhosis of different etio-logies. Eighteen out of 178 patients - 7 females and 11 males - displayed elevated serum pro-lactin levels. When patients were excluded who suffered from co-morbidities or took medication that are discussed to potentially interfere with prolactin metabolism, only 3 males displayed increased serum prolactin levels. Prolactin levels were similar in patients with liver cirrhosis of different etiologies. Our data suggest that hyperprolactinemia is not commonly found in patients with liver cirrhosis, but is mostly associated with intake of drugs or presence of comorbidites which are known to potentially cause hyperprolactinemia. We thus hypothesize that in contrast to former studies liver cirrhosis is not a common cause of hyperprolactinemia and that in the absence of co-morbidities or drugs that are known to potentially increase prolactin levels, marked hyperprolactinemia needs further investigation in patients with liver cirrhosis.

The novel insulin resistance parameters RBP4 and GLP-1 in patients treated with valproic acid: just a sidestep?

Valproic acid (VPA), as one of the most widely prescribed antiepileptic drugs (AED) for many types of epilepsy in adults and children, is associated with weight gain, alteration of adipocytokine homeostasis, insulin resistance and Non-Alcoholic Fatty Liver Disease (NAFLD). Retinol-binding protein 4 (RBP4) and Glucagon-like peptide-1 (GLP-1) are considered as important new targets in modern type 2 diabetes mellitus therapy linked to insulin resistance, NAFLD and visceral obesity acting via peripheral or central mechanisms. We herein demonstrate the lack of an influence of VPA treatment on RBP4 and GLP-1 in otherwise healthy patients. In summary, the absence of any relationship with RBP4 and GLP-1 concentrations does not suggest a role of these novel insulin resistance parameters as potential regulators of glucose and fat metabolism during VPA-therapy.

LRP1b shows restricted expression in human tissues and binds to several extracellular ligands, including fibrinogen and apoE-carrying lipoproteins.

OBJECTIVE: To investigate low-density lipoprotein receptor-related protein 1b (LRP1b) expression in human tissues and to identify circulating ligands of LRP1b. METHODS AND RESULTS: Using two independent RT-PCR assays, LRP1b mRNA was detected in human brain, thyroid gland, skeletal muscle, and to a lesser amount in testis but absent in other tissues, including heart, kidney, liver, lung, and placenta. Circulating ligands were purified from human plasma by affinity chromatography using FLAG-tagged recombinant LRP1b ectodomains and identified by mass spectrometry. Using this technique, several potential ligands (fibrinogen, clusterin, vitronectin, histidine rich glycoprotein, serum amyloid P-component, and immunoglobulins) were identified. Direct binding of LRP1b ectodomains to fibrinogen was verified by co-immunoprecipitation. ApoE-carrying lipoproteins were shown to bind to LRP1b ectodomains in a lipoprotein binding assay. Furthermore, binding as well as internalization of very low density lipoproteins by cells expressing an LRP1b minireceptor was demonstrated. DISCUSSION: LRP1b expression in humans appears to be confined to few tissues, which could point out to specialized functions of LRP1b in certain organs. Most of the newly identified LRP1b ligands are well-known factors in blood coagulation and lipoprotein metabolism, suggesting a possible role of LRP1b in atherosclerosis.

Effects of weight loss on PLTP activity and HDL particle size.

OBJECTIVE: Dyslipidaemia in obesity is characterized by hypertriglyceridaemia, low HDL-C levels, small, dense HDL particles and increased phospholipid transfer protein (PLTP) activity. METHODS: In the present study, we investigated PLTP activity and HDL particle size in 16 morbidly obese, middle-aged women, who underwent Swedish Adjustable Gastric Banding surgery. Study subjects were tested within 2 months before and 1 y after surgery. PLTP activity was determined by exogenous substrate assay and HDL particle size by gradient gel electrophoresis, respectively. RESULTS: Pronounced weight loss after gastric banding surgery resulted in a significant decrease of PLTP activity from 8.42+/-2.04 to 7.43+/-2.21 micromol/ml/h (P=0.02). The size of HDL(2) particles increased signficantly from 14.04+/-0.86 to 14.28+/-0.64 nm (P=0.02) after body weight reduction, while no change in HDL(3) particle size was apparent. DISCUSSION: Our results suggest that dyslipidaemia in obesity is--at least partially--reversible by weight loss. We hypothesize that reduction of PLTP activity and increase of HDL particle size are important component factors in converting the atherogenic lipoprotein profile of obese subjects into a less atherogenic profile with weight loss.

CDTect-RIA and CDTect-EIA for determination of serum carbohydrate-deficient transferrin compared.

CDTect-RIA and CDTect-EIA for determination of serum carbohydrate-deficient transferrin (CDT) by radioimmunoassay and enzyme immunoassay respectively were tested for equality and precision in four European laboratories. For correlational studies, serum samples with CDT concentrations up to 130 U/l were analysed in accordance with a uniform trial schedule. The regression of CDT values obtained by the two procedures was computed for each laboratory using the method of Passing and Bablok. Slopes and intercepts of the regression functions did not differ significantly from the values 1 or 0, as proved by the corresponding 95% confidence intervals. Precision studies were computed using analysis of variance. For CDT concentrations at the upper reference limit for men, the within-day coefficients of variation (CVs) ranged between 0.7 and 6.4% (median 5.2%) for CDTect-RIA and from 4.3 to 9.2% (median 6.2%) for CDTect-EIA. The corresponding pure between-day CVs were 5.0-18.5% (median 9.8%) and 3.5-14.5% (median 10.9%). The study demonstrates the equality of CDT values obtained by CDTect-RIA and CDTect-EIA. According to this study, the two methods can be used interchangeably without getting fluctuating CDT values, e.g. in longitudinal studies.

3D volume-ablation rate and thermal side effects with the Er:YAG and Nd:YAG laser.

OBJECTIVES: The aim of this investigation was to determine the influence of a variety of parameters on the effectiveness of hard substance ablation and the thermal side effects when using Er:YAG laser (Key I and II, KaVo) and Nd:YAG laser (SunLase 800, Sunrise Technologies/Orbis). METHODS: For this study, ablation and temperature measurements were carried out on 170 dentin slices and 170 extracted teeth via computer-controlled cavity preparation. The Er:YAG laser settings varied from 250-400 mJ/pulse, 3-15 pps and 20-180 s processing time, and in the case of the Nd:YAG laser from 83-100 mJ/pulse, 10-20 pps, and 20-260 s processing time. The ablation rate was measured volumetrically via a 3D sensor. Temperatures were measured for each setting both on the dentin slice and in the pulp of the extracted teeth. The results were analyzed using a t-test for independent samples and a one-way ANOVA (Bonferroni). Also a liner regression analysis was done using Pearson's coefficient. RESULTS: The results show that with the Er:YAG laser, in combination with water-spray cooling, an effective 3D ablation rate (up to 0.017 mm3/pulse = 50 microns linear) can be achieved without raising the temperature of the surrounding tissue. In the case of the Nd:YAG laser, no measurable ablation rate was evident without conditioning of the dentin surface and, in the case of conditioning with black ink, a low ablation rate (0.00004 mm3/pulse = linear 0.2 micron/pulse) was found. SIGNIFICANCE: In contrast to the Er:YAG laser, it is apparent, that with the Nd:YAG laser from a total energy of 80 J onwards, the rise in temperature in the pulp is above 8 degrees C. For that reason, the use of the Nd:YAG laser at higher total energies is not recommended. The temperature rise with the Nd:YAG laser is dependent on the direction of the dentin tubuli. Dentin tubuli running parallel to the surface prevent significant heat penetration, whereas those running in a transverse direction to the surface (= parallel to the laser beam) support the penetration of heat. This finding supports the light-propagating theory for spreading effects of laser beams in dentin.

The connection between dystocia and dysmenorrhoea.

Eight hundred and eighty women having their first baby were asked whether they had had dysmenorrhoea; 61 per cent had and 39 per cent had not. Eleven per cent of the former had to have forceps, ventouse or caesarean section, compared with twice as many (20.8 per cent) of the latter (p = 0.001). Those with severe dysmenorrhoea had a greater need for operative interference (not statistically significant). I suggest, after 21 years of observation, that the level of prostaglandin activity may be different in these women, and that a history of no dysmenorrhoea or severe dysmenorrhoea might be considered as a risk factor for a complicated delivery.

A labour-saving manoeuvre.

Slow progress in the first stage of labour was treated in 792 mothers by digital dilatation. This manoeuvre is described. Partial dilatation was converted to complete dilatation in 94.4 per cent of all cases, the incidence of success being 90.0 per cent in primiparae and 96.0 per cent in multiparae. Difficulties are described, but serious complications were conspicuously absent.The manoeuvre was helpful with mothers unable to resist premature bearing down, and especially valuable for reducing delay before applying forceps for fetal distress. The early perinatal loss of 20 (in the first 200 cases) was reduced to 3.3 (in the last 599 births) after a change of technique.