[Spatial accessibility to animal health care - a GIS based analysis]. / Räumliche Zugänglichkeit zu tiermedizinischer Versorgung ­ eine GIS-basierte Analyse.

INTRODUCTION: Various studies from the past years examine the changing conditions and challenges in the veterinary sector. Secured access to public and private care services is a prerequisite for a holistically oriented health care system ("One Health"). In the present study, a multidimensional concept of accessibility to care services was used for the first time to determine and visualize the density of the animal health care system in Switzerland. Traditional indicators used to describe care structures focus either on availability or accessibility. In order to overcome the limitations of traditional indicators, the family of methods known as Floating-Catchment-Area-Methods (FCA) has been developed in care geographical research. The strength of FCA methods lies in the fact that they output accessibility independent of administrative boundaries and at the same time consider the spatial distance and available capacities. The study provides insight into the density of animal health care services using FCA methods and geographical information systems (GIS). Data on providers of veterinary services in the companion animal sector and, on the demand side, data on dogs and cats kept in Switzerland served as illustrative example. The result was interactive maps of the density of health care and the structure of spatial accessibility to veterinary providers and consumers. As expected, high spatial accessibility is found in the urban centers and the agglomerations of the Central Plateau. In contrast, spatial accessibility to medical services for dogs and cats is often lower in peripheral areas. Due to hitherto unavailable data, various analyses had to be postponed for the time being. For example, the model could of course be extended to all animal species and all types of medical services. In addition, it would also be possible to forecast the future density of health care, or to optimize the care system. Together with the relevant industry stakeholders, these gaps could be closed, and the model and the resulting findings could be further differentiated. The results should serve private actors in the concerned value chains, but also decision-makers in the public veterinary service, governmental authorities, agricultural bodies, universities, etc. as a basis for strategic decisions regarding the issue of medical supply density and care services in the animal sector.

INTRODUCTION: Ces dernières années, divers travaux ont examiné l'évolution des conditions cadres et des défis dans le secteur vétérinaire. L'assurance d'un accès aux soins publics et privés est une condition préalable à un système de santé holistique (« One Health ¼). Dans le travail présent, on a tenté pour la première fois d'enregistrer et de visualiser la densité d'approvisionnement du système de soins vétérinaires en Suisse en utilisant un concept multidimensionnel d'accessibilité aux offres de soins. Les indicateurs traditionnels pour décrire les structures de soins se concentrent soit sur la disponibilité soit sur l'accessibilité. Afin de contrer les limites des indicateurs traditionnels, la famille de méthodes du Floating-Catchment-Area (FCA) s'est développée dans la recherche en géographie sanitaire. La force des méthodes FCA est qu'elles fournissent un accès indépendamment des limites administratives, tout en tenant compte de la distance spatiale et de la capacité disponible. Ce travail permet d'avoir un aperçu de la densité de l'offre vétérinaire en utilisant la méthodologie FCA en tenant compte de systèmes d'information géographique (SIG). Les données sur les prestataires de services vétérinaires dans le secteur des animaux de compagnie et sur la demande concernant les chiens et les chats vivant en Suisse ont servi d'exemple. Le résultat a été des cartes interactives de la densité de l'offre et de la structure de l'accessibilité spatiale aux prestataires vétérinaires et de celle des consommateurs. Comme prévu, il existe un degré élevé d'accessibilité spatiale dans les centres urbains et les agglomérations du plateau suisse. En revanche, l'accessibilité spatiale aux services vétérinaires pour chiens et chats est souvent plus basse dans les zones périphériques. En raison de données indisponibles précédemment, diverses analyses ont dû être abandonnées dans un premier temps. Ce modèle pourrait être étendu à toutes les espèces animales et aux diverses offres vétérinaires. En outre, il serait également possible de faire des prévisions sur la future densité de l'offre ou sur son optimisation. Conjointement avec les acteurs de la branche concernés, ces lacunes pourraient être comblées avec certitude et le modèle et les résultats qui en résulteraient seraient encore plus différenciés. Les résultats sont destinés à aider les acteurs privés dans les chaînes de valeur ajoutée, mais ils pourraient aussi servir de base aux décideurs des services vétérinaires publics, aux autorités d'exécution, aux organes de l'agriculture, aux universités, etc., pour prendre des décisions stratégiques autour du thème de la densité de l'offre médicale dans le secteur animal.

Modulatory effect of glucose, amino acids, and secretin on CCK-8-induced somatostatin and pancreatic polypeptide release in dogs.

Protein- and fat-rich test meals elicit a strong stimulatory effect on postprandial somatostatin (SLI) and pancreatic polypeptide (PP) release, whereas carbohydrate-rich meals rather attenuate the response of both hormones. Since there is evidence that intestinal hormones might contribute to the postprandial SLI and PP response, it was the aim of the present study to determine in dogs the effect of low-dose cholecystokinin octapeptide (CCK-8) on basal hormone levels and also during a background infusion of amino acids or glucose. In a group of six conscious dogs, sulfated CCK-8 was infused intravenously (i.v.) via a hindleg vein at stepwise increasing infusion rates of 10, 30, and 50 pmol X kg-1 X h. The infusion of CCK was applied during a background infusion of saline (2 ml/min), glucose (0.2 g/min), or an amino acid mixture (8.5%, 2 ml/min). CCK-8 had no effect on plasma insulin and glucagon levels under all experimental conditions. Plasma SLI levels were significantly stimulated by all doses of CCK. This stimulatory effect was similar during background infusions of either saline, glucose, or amino acids, respectively. Pancreatic polypeptide (PP) levels rose 200-300 pg/ml during CCK plus saline. This was slightly attenuated by glucose. During CCK plus amino acids, the PP response was augmented to 600-800 pg/ml. Since secretin is also released after the ingestion of a meal and intraduodenal acidification is a potent stimulus not only of secretin but also of gastric and pancreatic SLI release, the effect of secretin was examined additionally.(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence for a role of endogenous opiates in postprandial somatostatin release.

Previously, we have demonstrated the effects of exogenously administered opiates on somatostatin release in dogs and therefore the present study was designed to determine the effect of endogenous opiates via naloxone-induced opiate receptor blockade on somatostatin release. Additionally, plasma insulin and pancreatic polypeptide (PP) levels were determined in response to intragastrically instilled protein, carbohydrate and fat test meals in a group of eight conscious dogs. To all test meals either naloxone (4 mg) or saline was added. The rise of plasma somatostatin levels in response to liver extract, sucrose and fat was attenuated significantly by naloxone. Naloxone had no effect on the rise of postprandial plasma insulin and PP levels. The present data demonstrate that endogenous opiates have a stimulatory effect on postprandial somatostatin release in dogs which indicates a tight interaction that might be of relevance for nutrient homeostasis.

Carbohydrates modulate opiate receptor mediated mechanisms during postprandial endocrine function.

The present study was designed to determine the role of carbohydrates during naloxone-induced opiate receptor blockade upon the postprandial rise of plasma somatostatin (SLI), insulin and pancreatic polypeptide (PP) levels in response to protein and fat test meals in conscious dogs. Test meals consisting of 50 g liver extract + 50 g sucrose or 50 g corn oil + 50 g sucrose dissolved in 300 ml water were instilled intragastrically, respectively. Additionally, liver extract and fat meals were given with a concomitant intravenous infusion of glucose. To all test meals either naloxone (4 mg) or saline was added. The addition of sucrose to liver extract or the infusion of i.v. glucose during the liver meal abolished the inhibitory effect of naloxone on the rise of postprandial somatostatin levels which has been described recently. The addition of carbohydrate either orally or intravenously to the fat meal resulted in an even stimulatory effect of naloxone upon the rise of postprandial somatostatin levels. Insulin levels were not changed during liver extract + sucrose or i.v. glucose, respectively. When sucrose or i.v. glucose was administered together with the fat meal the addition of naloxone augmented postprandial insulin secretion. Pancreatic polypeptide (PP) release was augmented during the combination of sucrose or i.v. glucose with the fat and liver meal when naloxone was present in the meals. The present data demonstrate that the addition of carbohydrates either orally or intravenously to fat and protein meals modulates the effect of endogenous opiates in the regulation of postprandial somatostatin, insulin and pancreatic polypeptide release in dogs in a way that carbohydrates induce inhibitory mechanisms that are mediated via endogenous opiate receptors.

Endogenous opioids modulate the effect of cholecystokinin on insulin release in dogs.

Recently we have demonstrated in dogs and man that endogenous opioids participate in the regulation of pancreatic endocrine function following the ingestion of a meal. Since intestinal hormones such as cholecystokinin (CCK) are also released by the presence of nutrients in the gastrointestinal tract and participate in the postprandial stimulation of pancreatic endocrine function, an interaction between CCK and endogenous opioids seems possible. The present study was designed to examine this further. In a group of 8 conscious dogs the octapeptide of CCK was infused intravenously in its sulfated (CCK-8S) or nonsulfated (CCK-8NS) form and in addition the tetrapeptide of CCK (CCK-4) was given at increasing infusion rates of 50, 200 and 500 pmol/kg . h, respectively. The experiments were performed during a background infusion of saline to assess the effect on basal insulin and during a background infusion of glucose (0.2 g/min) to determine the effects on stimulated insulin release. The effect of endogenous opioids was examined by addition of the opiate-receptor antagonist naloxone. The studies demonstrate that in the basal state CCK-8S has no stimulatory effect on insulin secretion unless naloxone is added indicating that endogenous opioids help to prevent insulin secretion in the absence of elevated glucose levels. During i.v. glucose naloxone reduced the stimulatory effect of CCK-8S at 50 and 200 pmol/kg . h and that of CCK-4 at 50 pmol/kg . h. Infusion of CCK-8S and CCK-4 at 500 pmol/kg . h had no effect on glucose-stimulated insulin levels, however, the addition of naloxone elicited a significant stimulatory effect. These data demonstrate stimulatory as well as inhibitory effects of endogenous opioids depending on the dose of CCK-8 and -4. CCK-8NS reduced glucose-stimulated insulin release already at the lowest dose of 50 pmol/kg . h. This was reversed to a stimulatory effect with the addition of naloxone. These data demonstrate that the interaction between CCK-8 and -4 and endogenous opioids on prestimulated insulin secretion is much more dependent on the dose of CCK - low doses induce stimulatory and high doses inhibitory mechanisms via endogenous opioids. In view of previous in vitro and in vivo studies with exogenously infused opiate-active compounds it might be speculated that increasing doses of CCK elicit a parellel increase in the release of endogenous opioids which might be responsible for some but certainly not all of the effects observed recently for the action of naloxone in the post-prandial state.

Extinction probability, regularity and asymptotic growth of Markovian populations.

"The distribution of the maximum and the extinction probability for a Markovian population is derived. Asymptotic growth is described, using the sequence of sojourn times. A regularity criterion for the processes under consideration exists under certain assumptions. For a class of processes with specific population-dependent transition rates the asymptotic behaviour is given explicitly."

Poisson convergence on continuous time branching random walks and multistage carcinogenesis.

A theorem for Poisson convergence on realizations of two-dimensional Branching Random Walks with an underlying continuous time Markov Branching Process is proved. This result can be used to gain an approximation for the number of cells having sustained a certain deficiency after a long time in multistage carcinogenesis.

[Measuring place for the detection of ultra-weak photon radiation]. / Messplatz zum Nachweis ultraschwacher Photonenstrahlung.

A measuring method for the detection of ultra-weak photon-radiation from living matter is described. Also the fluorescence-radiation is provable. The latter is of necessity for special-fluorescence investigations. A proof-sensibility of phi = 1.483 10(-16)W (respectively 7.63 10(-17)W for the distance of 65.5 mm-filter - slide replaced by trial-slide) is calculable for lambda = 554 nm with the device constant found out.