Mutations in the melanocortin-4 receptor (MC4R) are associated with severe obesity, independent of their effect on cortisol or thyroid-stimulating hormone levels. We examined a morbidly obese male (BMI = 62 kg/m(2)) with a binge-eating disorder and eight family members for mutations in the MC4R gene and potential differences in leptin levels. Fifty healthy individuals served as controls. Sequence analysis revealed a novel heterozygous missense mutation (c.302 C>A, p.T101N) located in the second transmembrane domain of the receptor, which was not detected in controls. The Fisher exact test revealed an association between the T101N mutation and history of obesity (P < 0.05) in the family. The Kruskal-Wallis test showed an association between the mutation and the leptin/BMI ratio (P < 0.05), while there was no association between the T101N mutation and diabetes or arterial hypertension in the family. Although the available family was small, we could show a significant association between the heterozygous T101N mutation and obesity.

The most common cause of Maturity-Onset Diabetes of the Young (MODY) are mutations in the Hepatic Nuclear Factor 1α (HNF-1α) gene, resulting in MODY3. In a family afflicted with diabetes, a novel nonsense mutation in HNF-1α, E41X, causing a termination codon behind the dimerization domain, was found. The penetrance in individuals older than 25 years was 81.8%. The age at manifestation of diabetes ranged from 18 to 63 years, only 2 out of 10 diabetic individuals developed the disease at ages younger than 25 years. Although diabetes duration lasted up to 35 years in this family, only one family member suffered from diabetic complications. Additional polymorphisms in HNF-1α, I27L and S487N, were found in this pedigree. Despite its biological inactivity, S487N polymorphism led in combination with E41X to a significant earlier manifestation of diabetes, whereas I27L polymorphism or increased Body Mass Index (BMI) did not. In spite of the severe gene defect, which truncates the protein behind the dimerization domain, the phenotype of E41X was relatively benign without frequent diabetic complications.

BACKGROUND:C-reactive protein (CRP) levels are modulated by endogenous and exogenous factors independently of inflammation. The present study investigated the impact of oral contraceptives, endogenous oestrogens, age, gender, smoking, body mass index (BMI) and lipid levels on CRP concentrations in a healthy collective.METHODS:Highly sensitive CRP, total cholesterol, HDL-cholesterol and LDL-cholesterol levels were measured in 850 blood donors (438 M, 412 F); 227 women in this group used oral contraceptive formulations (OC). Additionally, serum samples from 58 women undergoing in vitro fertilization cycles (IVF) were tested for CRP. Results. The 97.5th percentile of CRP levels of the blood donors was 4.91 mg/L in men, 7.52 mg/L in OC non-users and 11.95 mg/L in OC users. Overweight gives a 2-fold increase of median CRP levels in men and women. The combination of overweight and OC use in women resulted in 6-fold median CRP levels. Age, smoking and lipid levels were influencing factors of lower significance. In IVF patients the elevated oestradiol levels had no influence on CRP concentrations in multivariance analysis.CONCLUSION:The diagnostic and predictive value of CRP levels is most affected by BMI and oral contraceptive use, which suggests the need for further investigations into the role of CRP modulating factors in monitoring infectious diseases.

Objective: Recent data suggest that mutations in the aryl hydrocarbon receptor interacting protein gene (AIP) are associated with pituitary adenomas. AIP is considered to be a tumour suppressor gene.Methods: 110 Caucasian patients living in Germany with pituitary adenoma (55 hormone secreting, 55 non-functioning) were examined for AIP mutations.Results: Three patients (2.7%) harboured an AIP germline mutation. A heterozygous mutation, R16H (c.47G>A), was found in two patients and a heterozygous G>C change in the 3'UTR, 60 bp downstream of the termination codon, in one patient. All three patients suffered from non-functioning adenoma. Additionally, a silent polymorphism, D172D (c.516C>T), was found in 3 patients with non-functioning adenoma, in 2 patients with prolactinoma and in one patient with acromegaly.Conclusions: AIP mutations are rare in sporadic pituitary adenomas in the German population and occur independently from a hormone secretion of the adenoma.

OBJECTIVE:The DG10S478 variant in the transcription factor 7-like 2 (TCF7L2) gene is a tetranucleotide repeat with six alleles. Alleles 0, 8 and 12 were found to account for 98% of chromosomes in population based controls. The composite allele X (non zero) has been associated with type 2 diabetes while allele 0 (no insertion) was described as protective. However, no data exist about the influence of DG10S478 variants on manifestation of diabetes and development of diabetic complications.METHODS:250 patients with type 2 diabetes were tested for the DG10S478 allele X and its association with diabetic complications, age at diagnosis of diabetes and BMI.RESULTS:Allele 0 was found in 42.4% of the examined patients, 45.2% of the participants were found to be heterozygous and 12.4% homozygous for the composite allele X. The correlation of allele X with the age at diagnosis of diabetes was not significant. There was also no association of allele X with retinopathy, nephropathy or neuropathy. Only the correlation with BMI was statistically significant.CONCLUSIONS:The DG10S478 variant seems to have no influence on manifestation of diabetes and the development of microvascular complications.

Thiazolidinediones such as pioglitazone have been shown to exert anti-inflammatory effects independent of their insulin sensitizing effects by reducing activation of the proinflammatory transcription factor NF-kappaB in animal models of experimental diabetes. Furthermore, short-term pioglitazone treatment ameliorates endothelial dysfunction in conduit arteries of patients with type 2 diabetes. Since inflammation is supposed to impair flow-mediated vasodilatation, we studied the effects of an 8-week pioglitazone intervention on endothelial function and mononuclear NF-kappaB activation in patients with type 2 diabetes. Twenty patients were included in a randomized, double-blind, placebo-controlled study receiving 30 mg pioglitazone or placebo, respectively. Flow-mediated endothelium dependent vasodilatation (FMD) of the brachial artery, NF-kappaB binding activity in peripheral blood mononuclear cells [pBMC, determined by electrophoretic mobility shift assay (EMSA)] and interleukin-6 (IL-6)-transcription rates (determined by real-time PCR) were measured at study entry and after eight weeks of intervention. Pioglitazone treatment resulted in a significant improvement of FMD (4.3%+/-3.3; p=0.003), while no effect was seen under placebo medication (2.0%+/-2.7; p=0.71). The correction of FMD was neither paralleled by a pioglitazone-dependent reduction in mononuclear NF-kappaB binding activity (DeltaNF-kappaB activity: pioglitazone: 9.2%+/-6.7, p=0.24; placebo: 5.7%+/-19.6; p=0.82) nor in NF-kappaB dependent gene transcription as determined for IL-6 (DeltaIL-6 pioglitazone: +1.8%+/-12.0, p=0.93; placebo: -0.2%+/-9.7; p=0.92). These data demonstrate for the first time that pioglitazone treatment improves endothelial dysfunction in patients with type 2 diabetes without affecting NF-kappaB binding activity and NF-kappaB dependent proinflammatory gene expression in pBMC.

Aim: The clinical specificity and sensitivity of the thyroid tests are affected by the set up of the reference ranges. The purpose of our study was to create new reference ranges for improved thyroid diagnostics using serum from apparently healthy subjects with sonographically assessed normal thyroid gland.

One hundred water samples (32 from clinical units and 68 from private households) were examined for Legionella by culture, fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR). Twenty-four samples were positive by culture (22 L. pneumophila; 2 non-pneumophila species), 36 by FISH (32 L. pneumophila; 4 non-pneumophila species) and 75 by PCR (41 positive for L. pneumophila; 26 positive for L. pneumophila and a non-pneumophila species; 8 positive for non-pneumophila species). PCR and FISH results were compared to bacterial culture as the "gold standard" method by calculating sensitivities and specificities, respectively: PCR assays, 96% and 47%; FISH assays, 67% and 72%, respectively. In comparison with FISH the lower specificity of PCR is probably caused by dead Legionella bacteria and/or free Legionella DNA in potable water, and the higher sensitivity of PCR may be explained by the detection limit of fluorescence microscopy. In conclusion, the relatively high specificity, sensitivity and quickness of the FISH assay offer significant advantages over conventional PCR and culture-based techniques.

The authors investigated the shift of local energy spectra with SPECT rotation for the GE 400 AT and the Picker Prism 3000 tomographs. A Co-57 flood source was taped to the parallel-beam collimator of the GE 400 AT; a Tc-99m line source was placed at the focus of the fan-beam collimator of one head of the Picker Prism. The count-based method, which employs a narrow window (about 4 keV) on the maximum slope of the photopeak, was used with both systems. Non-linear, polynomial spectral fitting was applied to x-y-E data acquisitions with the GE camera. The fitting yielded either shifts or shifts and width changes. Results show 1) the shifts are pseudo-sinusoidal with angle and similar for different spatial locations, 2) the average of their absolute value is 0.71 keV and 0.13 keV for the GE and Picker cameras, respectively, 3) width changes for the GE camera are small and appear random, 4) the calculated shifts from the count-based method for the central part of the GE camera are correlated with those from the spectral fitting method. They are 12% smaller. The conclusion is that energy shifts with angle may be present with most rotating cameras although they are smaller with newer cameras. It probably will be necessary to account for them in schemes designed for high-accuracy compensation of Compton-scattered gamma rays although they perhaps could be ignored for newer cameras

A multienergy data acquisition system based on the Macintosh II computer and a commercial ADC (analog-to-digital converter) subsystem has been developed to allow the application of sophisticated Compton-scatter correction procedures. The system has been interfaced with a GE 400AT SPECT (single photon emission computed tomography) camera system, and preliminary testing has shown that the system will perform well enough to allow evaluation of various Compton-scatter correction methods in SPECT imaging. The system digitizes position and energy signals from the camera to 12 b, bins the data into images, and transfers the data via an Ethernet interface to an extensive computer network for reconstruction and analysis. The system provides gantry control signals for tomographic acquisition. Although the present count rate capability is rather limited, it is nevertheless a flexible, inexpensive acquisition platform capable of acquiring the multienergy data required to develop improved scatter correction methods.< >