Endogenous glucagon-like peptide 1 controls endocrine pancreatic secretion and antro-pyloro-duodenal motility in humans

Background: Exogenous use of the intestinal hormone glucagon-like peptide 1 (GLP-1) lowers glycaemia by stimulation of insulin, inhibition of glucagon, and delay of gastric emptying.Aims: To assess the effects of endogenous GLP-1 on endocrine pancreatic secretion and antro-pyloro-duodenal motility by utilising the GLP-1 receptor antagonist exendin(9-39)amide (ex(9-39)NH2).Methods: Nine healthy volunteers underwent four experiments each. In two experiments with and without intravenous infusion of ex(9-39)NH2 300 pmol/kg/min, a fasting period was followed by intraduodenal glucose perfusion at 1 and 2.5 kcal/min, with the higher dose stimulating GLP-1 release. Antro-pyloro-duodenal motility was measured by perfusion manometry. To calculate the incretin effect (that is, the proportion of plasma insulin stimulated by intestinal hormones) the glycaemia observed during the luminal glucose experiments was mimicked using intravenous glucose in two further experiments.Results: Ex(9-39)NH2 significantly increased glycaemia during fasting and duodenal glucose. It diminished plasma insulin during duodenal glucose and significantly reduced the incretin effect by approximately 50%. Ex(9-39)NH2 raised plasma glucagon during fasting and abolished the decrease in glucagon at the high duodenal glucose load. Ex(9-39)NH2 markedly stimulated antroduodenal contractility. At low duodenal glucose it reduced the stimulation of tonic and phasic pyloric motility. At the high duodenal glucose load it abolished pyloric stimulation.Conclusions: Endogenous GLP-1 stimulates postprandial insulin release. The pancreatic \textgreeka cell is under the tonic inhibitory control of GLP-1 thereby suppressing postprandial glucagon. GLP-1 tonically inhibits antroduodenal motility and mediates the postprandial inhibition of antral and stimulation of pyloric motility. We therefore suggest GLP-1 as a true incretin hormone and enterogastrone in humans

Distribution of Complex and Core Lipids within New Hyperthermophilic Members of the Archaea Domain

Core and complex lipids of several new hyperthermophilic archaeal isolates were analyzed. The organisms belong to the Sulfolobales,Archaeoglobus, Pyrobaculum, and Methanococcus. A detailed structural investigation of complex lipids of Pyrobaculum species is reported. The different lipid structures are of help for a rapid and simple phylogenetic classification of the new isolates. They are in agreement with the classification based on other features

Regeneration of High Pressure Turbine Blades. Development of a Hybrid Brazing and Aluminizing Process by Means of Thermal Spraying

Besides welding, high temperature vacuum repair-brazing is already established for nickel-based alloy turbine blades in the aerospace and power plant industries. After the worn turbine blade has been decoated to its substrate material, the filler metal is deposited as a paste, (melt-spin) foil or tape which also consists of a nickel-based alloy. Following this, the hot-gas corrosion protective coating (e.g. NiCoCrAlY) is applied using thermal spraying. The brazed turbine blade is ground or milled to size and subsequently aluminized to further increase its corrosion resistance. Using the current state of technology, a turbine blade can undergo approximately 3 to 4 repair cycles. In the present study, the development of a two-stage hybrid technology for repairing turbine blades is considered which incorporates, on the one hand, a process technology and manufacturing aspects and, on the other hand, considers material-technological mechanisms. During the first stage of this hybrid technology, the filler metal together with the hot-gas corrosion protective coating is applied using thermal spraying. The subsequent second stage combines the brazing and aluminizing processes. The technology developed here brings technical and economic advantages whilst enabling the current state-of-the-art's corresponding process chain for repairing turbine blades to be shortened.DFG/SFB/87

Stereotactic arrhythmia radioablation: competitor or adjunct to catheter ablation?

Cardiology and Radiation Oncology working together—a new ‘STAR’ on the horizon? Until recently, most cardiologists associated radiation exposure to the heart with potential adverse effects, such as pericarditis, late coronary artery disease or potential damage to cardiac implantable devices. The landmark publication of 2017 reporting a case series of just five patients with recurrent ventricular tachycardia (VT) treated with stereotactic arrhythmia radioablation (STAR) changed this perception and introduced a new area for both cardiac electrophysiology and radiation oncology

Functioning and disability in multiple sclerosis from the patient perspective

Multiple sclerosis (MS) has a great impact on functioning and disability. The perspective of those who experience the health problem has to be taken into account to obtain an in-depth understanding of functioning and disability. The objective was to describe the areas of functioning and disability and relevant contextual factors in MS from the patient perspective. A qualitative study using focus group methodology was performed. The sample size was determined by saturation. The focus groups were digitally recorded and transcribed verbatim. The meaning condensation procedure was used for data analysis. Identified concepts were linked to International Classification of Functioning, Disability and Health (ICF) categories according to established linking rules. Six focus groups with a total of 27 participants were performed. In total, 1327 concepts were identified and linked to 106 ICF categories of the ICF components Body Functions, Activities and Participation and Environmental Factors. This qualitative study reports on the impact of MS on functioning and disability from the patient perspective. The participants in this study provided information about all physical aspects and areas of daily life affected by the disease, as well as the environmental factors influencing their lives

Does genetic differentiation underlie behavioral divergence in response to migration barriers in sticklebacks?:A common garden experiment

Water management measures in the 1970s in the Netherlands have produced a large number of “resident” populations of three-spined sticklebacks that are no longer able to migrate to the sea. This may be viewed as a replicated field experiment, allowing us to study how the resident populations are coping with human-induced barriers to migration. We have previously shown that residents are smaller, bolder, more exploratory, more active, and more aggressive and exhibited lower shoaling and lower migratory tendencies compared to their ancestral “migrant” counterparts. However, it is not clear if these differences in wild-caught residents and migrants reflect genetic differentiation, rather than different developmental conditions. To investigate this, we raised offspring of four crosses (migrant ♂ × migrant ♀, resident ♂ × resident ♀, migrant ♂ × resident ♀, resident ♂ × migrant ♀) under similar controlled conditions and tested for differences in morphology and behavior as adults. We found that lab-raised resident sticklebacks exhibited lower shoaling and migratory tendencies as compared to lab-raised migrants, retaining the differences in their wild-caught parents. This indicates genetic differentiation of these traits. For all other traits, the lab-raised sticklebacks of the various crosses did not differ significantly, suggesting that the earlier-found contrast between wild-caught fish reflects differences in their environment. Our study shows that barriers to migration can lead to rapid differentiation in behavioral tendencies over contemporary timescales (~ 50 generations) and that part of these differences reflects genetic differentiation

Antarctic sympagic meiofauna in winter: Comparing diversity, abundance and biomass between perennially and seasonally ice-covered regions

This study of Antarctic sympagic meiofauna in pack ice during late winter compares communities between the perennially ice-covered western Weddell Sea and the seasonally ice-covered southern Indian Ocean. Sympagic meiofauna (proto- and metazoans >20 μm) and eggs >20 μm were studied in terms of diversity, abundance and carbon biomass, and with respect to vertical distribution. Metazoan meiofauna had significantly higher abundance and biomass in the western Weddell Sea (medians: 31.1×103 m−2 and 6.53mg m−2, respectively) than in the southern Indian Ocean (medians: 1.0×10 103 m−2and 0.06 mg m−2, respectively). Metazoan diversity was also significantly higher in the western Weddell Sea. Furthermore, the two regions differed significantly in terms of meiofauna community composition, as revealed through multivariate analyses. The overall diversity of sympagic meiofauna was high, and integrated abundance and biomass of total meiofauna were also high in both regions (0.6–178.6×103 m−2 and 0.02–89.70mg m−2, respectively), mostly exceeding values reported earlier from the western Weddell Sea in winter. We attribute the differences in meiofauna communities between the two regions to the older first-year ice and multi-year ice that is present in the western Weddell Sea, but not in the southern Indian Ocean. Our study indicates the significance of perennially ice-covered regions for the establishment of diverse and abundant meiofauna communities. Furthermore, it highlights the potential importance of sympagic meiofauna for the organic matter pool and trophic interactions in sea ice