Exendin-4 decelerates food intake, weight gain, and fat deposition in Zucker rats.

Exendin-4 is a 39 amino acid peptide produced in the salivary gland of the Gila monster lizard. It has a 53% amino acid homology to the incretin hormone glucagon-like peptide-1 (GLP-1). Exendin-4 induces insulin release through activation of the GLP- 1 receptor but is a much more potent insulinotropic agent than GLP-1. Of critical importance for its potential use as a treatment for diabetes is its much longer biological effect in vivo. Previous studies involving once daily administration of exendin-4 over 13 weeks to db/db mice demonstrated that it lowers hemoglobin A1c (HbA1c), a marker of mean blood glucose levels. Food consumption in the treated animals dropped over the first 4 days and then increased to a level comparable with that of the untreated animals. In this study, we initially examined the effect of once daily injections (over 14 days) on the food consumption of Zucker fatty rats. We observed an immediate reduction in food intake which then leveled off(after 5 days) to match that of the untreated animals. Subsequently we injected the same animals twice daily (treatment period of 56 days in total) and observed a sustained reduction in food intake and weight-gain. This was matched by a reduction in the critical parameters of HbA1c, fasting blood glucose and plasma insulin. MRI imaging of the abdominal regions of the animals showed that initially only the amount of fat deposited in the sc region was reduced after 4 weeks exendin-4 treatment. At the 8-week time point there was a corresponding decrease in the amount of visceral fat deposition. The combination of appetite reduction, decreased fat deposition and an improvement in the parameters associated with glucose intolerance makes a case for the use of exendin-4 as a treatment for diabetes.

NMR Microscopy and Image Processing for the Characterization of Flexible Polyurethane Foam.

NMR tomography in material science? Three-dimensional images with a spacial resolution of 10 µm are now possible for porous, liquid-containing materials with NMR microscopy. They can be processed further with image evaluation methods and used, for example, for the characterization of open-cell foams (see illustration).

NMR microscopy of polyurethane foams.

NMR microimaging has been applied to the characterization of foam materials, in order to understand their properties and gain deeper insight into their structures. The structure of "open cell" foams can be visualized with sufficient resolution to obtain the size and shape of cells, as well as their spatial distribution within specimens. Statistics of cell sizes have been calculated from NMR microscopy and are in good agreement with results obtained from electron microscopy. We demonstrate that the local density of foams, which are parameters largely inaccessible by other analytical methods, readily can be determined by NMR microscopy.

In vivo and in vitro investigations of hydration effects of beauty care products by high-field MRI and NMR microscopy.

AIM: Data obtained from in vivo and in vitro measurements on human skin and skin samples are presented. METHODS: In vivo measurements, using a 3-Tesla magnetic resonance system, on the forearm of three female volunteers show an increase of signal intensity, after application of cream, between 30% and 58%, depending on the cream type. In-plane resolution was 90 microm, with slice thickness of 2 mm. Chemical-shift-selective in vitro microimaging studies were performed on a 9.4-T spectrometer using human skin samples from the abdomen. In these experiments, in-plane resolution was 4 microm and slice thickness was 100 microm. RESULTS: The results demonstrate clearly the moisturising effect of beauty care products on the stratum corneum, which can be identified in in vitro experiments. No ingress into the skin of the lipid components of the emulsions could be observed in vitro. However, skin occlusion and consequently a long-lasting moisturising effect cannot be excluded. CONCLUSIONS: These results prove the capability of magnetic resonance imaging to investigate human skin in vivo and in vitro, and to follow the skin penetration of beauty-care products and pharmaceutical ointments.

[The examination card for a child with suspected hearing loss or deafness]. / Karta badania dziecka podejrzanego o niedosluch lub gluchote.

An audiological examination card for a child has been worked out, allowing a detailed collection of anamnestic data concerning: family history, gestation, labour, neonatal period, infancy and early childhood. The items and possible answers contained in the card are so prepared that it can be used for computer analysis of the data obtained.

Fourier analysis in the objectivisation of auditory brain stem responses in newborns.

Fourier analysis (FFT) of auditory brain stem responses induced by stimuli of 90, 70 and 40 dB HL was carried out in group of 45 full-term and pre-term neonates. It was stated that with postnatal newborn's development complex IV/V was observed more frequently for the more immature newborn. It influences also the power strength spectrum obtained. In responses with IV/V complex the frequency range is considerable and significantly reduced by about 100-200 Hz. It was observed that general state of newborn at the birth influences the frequency range as well as from the shape of score reproducibility and reliability of spectrum is significantly better. It was noticed also that the shape and form of spectrum in about threshold and threshold responses is significantly similar irrespective of the intensity of threshold stimulus. The shape and form of responses spectra for stimuli of 30-40 dB HL (in a group of children with normal hearing) and of 80-90 dB HL (in a group of children with severe hearing impairment) are identical. The above findings allow us to show the importance of Fourier analysis for objectivisation of subjective evaluation of auditory brain stem responses.

Spectral analysis of auditory brain stem responses in perceptive hearing loss.

The Fourier analysis of auditory brain stem responses in 45 patients aged 19 to 56 treated because of perceptive hearing loss in Cracow ORL Clinic was carried out. The group consisted of: 15 patients with sudden deafness, 15 patients with Menier's disease and 15 cases with retrocochlear hearing impairment. In cases with recruiting cochlear hearing loss considerable and significantly extension of frequency range in brain stem responses was observed. Moreover, responses induced by stimulus intensity causing recruitment are identical for both ears as far as their shape and power spectrum is concerned, despite wide variety of responses caused by stimulus of different intensity. It is assumable that Fourier analysis of auditory brain stem responses gives possibility of objective evaluation of subjectively determined recruitment syndrome.