Bimodal regulation of pancreatic exocrine function in vitro by somatostatin-28

The action of natural and synthetic somatostatin-(1--28), [Nle8]somatostatin-(1--28), somatostatin-(15--28), and somatostatin-(1--14) was examined in dispersed acini from guinea pig pancreas. At high concentrations, the 28-amino acid form of somatostatin increased amylase release, outflux of 45Ca, cellular cGMP, and to a lesser extent cellular cAMP. The increase in amylase release was suppressed by dibutyryl cGMP but was not modified by theophylline or atropine. Binding of 125I-labeled [Thr28, Nle31] cholecystokinin-(25--33) was inhibited by [Nle8]somatostatin-(1--28). These effects required the entire 28-amino acid peptide and appeared to result from occupation of cholecystokinin receptors. It is postulated that they involve interactions between the C-terminal and the N-terminal sequences of the molecule with the participation of the amino acid in position 8. At low concentrations, natural and synthetic forms of somatostatin-(1--28) and somatostatin-(15--28) inhibited secretin- and vasoactive intestinal peptide (VIP)-stimulated increases in cellular cAMP concentration. No difference was found between the potency of somatostatin peptides, indicating that the tetradecapeptide somatostatin-(15--28) is sufficient to exert an inhibitory action on secretin- and VIP-stimulated cellular cAMP concentration. By contrast, the somatostatin fragment S-(1--14) was inactive on pancreatic cellular function.     

Abductive reasoning with recurrent neural networks.

Abduction is the process of proceeding from data describing a set of observations or events, to a set of hypotheses which best explains or accounts for the data. Cost-based abduction (CBA) is a formalism in which evidence to be explained is treated as a goal to be proven, proofs have costs based on how much needs to be assumed to complete the proof, and the set of assumptions needed to complete the least-cost proof are taken as the best explanation for the given evidence. In previous work, we presented a method for using high order recurrent networks to find least cost proofs for CBA instances. Here, we present a method that significantly reduces the size of the neural network that is produced for a given CBA instance. We present experimental results describing the performance of this method and comparing its performance to that of the previous method.     

Normal transitions in synthesis of replacement histones H2A.Z and H3.3 during differentiation of dystrophic myotube cells. A brief note

We previously reported that differentiating G0 myotube cells cultured from normal chicken embryos exhibit a histone synthesis pattern that is highlighted by transitions in the expression of the minor replacement variants H3.3 and perhaps H2A.Z (Wunsch and Lough, Dev. Biol. 119 (1987) 94-99). Because these proteins may be synthesized to maintain chromatin structure during the differentiation and maturation of the skeletal muscle fiber, it was of interest to determine whether they are made at normal levels during the differentiation of dystrophic muscle. To this end, the synthesis of histone proteins in cultured myoblasts and myotubes from normal and dystrophic avian embryos has been characterized by two-dimensional polyacrylamide gel electrophoresis and fluorography. Proliferating myoblasts (day 1) as well as two stages of differentiating myotubes (days 3, 4) exhibited histone synthesis patterns that were indistinguishable when comparing normal and dystrophic cells. It is noteworthy that this study also revealed that, in both cell types, the change in H2A.Z synthesis during the myoblast/myotube transition was remarkable, increasing from approximately 20% of the non-ubiquitinated H2As in myoblasts to 80% in myotubes. Also, gel staining patterns and immunoblotting detected no differences in the degree of histone ubiquitination between normal and dystrophic cells. These findings indicate that, up to this point in dystrophic differentiation, neither the synthesis nor ubiquitination of histones are perturbed.     

Qualit?t der ambulanten R?ntgenthoraxuntersuchung des Kindes – eine Pilotstudie

Am Beispiel des Klientels einer Kinderarztpraxis wurde eine Qualit?tskontrolle der ambulanten R?ntgenthoraxuntersuchung von Kindern durchgeführt. über einen 8-monatigen Studienzeitraum wurde mittels semiquantitativer Scores und quantitativer Messungen die technische Qualit?t von 139 konventionellen Thoraxaufnahmen unter Berücksichtigung von diagnostischen und strahlenhygienischen Aspekten beurteilt.     

Statisch-dynamische MR-Urographie Vergleich mit Ausscheidungsurographie und Szintigraphie bei experimentell induzierter Harntransportst?rung (HTS) Vergleich mit Ausscheidungsurographie und Szintigraphie bei experimentell induzierter Harntransportst?rung (HTS)

Ziel. Einsch?tzung der Wertigkeit der kombinierten statisch-dynamischen MR-Urographie (MRU) zur umfassenden funktionell-morphologischen Diagnostik tierexperimentell induzierter Harntransportst?rungen.     

Abdominal tumours in children: 3-D visualisation and surgical planning.

INTRODUCTION: Solid abdominal tumours are of special importance in the field of paediatric surgery. Because of the dangers of cumulative irradiation and improved delineation of soft parts MRI is usually employed in children for diagnostic assessment. Compiling the radiologic information for surgical planning is often difficult by conventional methods. Newly improved and efficient 3-D volume rendering software is now available for visual reconstruction of tumour anatomy utilising segmentation and other special techniques. Because the intraoperative complication rate is close to 20 % as described in the literature, optimal preoperative visualisation and planning would seem imperative. MATERIALS AND METHODS: All children with solid abdominal tumours at Heidelberg University in the year 2002 were included in this study. MR examinations were performed with a 0.5 Tesla magnet using a standard protocol. All MR data were processed with VG Studio Max 1.1, converting the two-dimensional data into three-dimensional data. RESULTS: This report presents 15 cases using this special technique: 7 with abdominal neuroblastoma, 6 with nephroblastoma, 1 ganglioneuroma, and 1 ovarian teratoma. CONCLUSIONS: Our experience shows that a better understanding of the surgical anatomy, particularly regarding the surrounding organs and vasculature, can be helpful in decreasing the incidence of inadvertent intraoperative injuries to these structures.