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Spontaneous ECL cell carcinomas in cotton rats: natural course and prevention by a gastrin receptor antagonist

In our inbred strain of cotton rats (Sigmodon hispidus) 50% of the females develop spontaneous ECL cell-derived tumors in the acid-producing part of the stomach due to hypergastrinemia secondary to gastric hypoacidity. Although the mechanism behind the hypoacidity is unknown, the female cotton rat is an excellent model for studying ECL cell-related tumorigenesis. In this study we wanted to explore

Oscillations of sessile drops of surfactant solutions on solid substrates with differing Hydrophobicity

The paper reports results of experimental studies on the dynamic behavior of surfactant olution drops on substrates with differing hydrophobicity. Contact angle oscillations observed immediately after the drop deposition are studied, and a mechanistic interpretation of this phenomenon is put forward. The major emphasis is put on the physicochemical aspects of surfactant action, including the dyna

Mechanisms and prevention of plant tissue collapse during dehydration: A critical review.

The appearance and functional properties are primordial in the quality assessment of semifinished fruit and vegetable products. These properties are often associated with shrunken, shriveled, darkened materials of poor rehydration ability after been subjected to air-drying—the most used drying method in the food industry. Fruits and vegetables are cellular tissues containing gas-filled pores that

Methodology to translate policy assessment problems into scenarios: the example of the SEAMLESS integrated framework

Scenario-based approaches in environmental and policy assessment studies are increasingly applied within integrated assessment and modelling frameworks. The SEAMLESS project develops such an integrated framework (SEAMLESS-IF) aiming to assess, ex-ante, impacts of alternative agro-environmental policies on the sustainability of agricultural systems. A particular challenge in this context is the con

Molecular engineering of a thermostable carbohydrate-binding module

Structure-function studies are frequently practiced on the very diverse group of natural carbohydrate-binding modules in order to understand the target recognition of these proteins. We have taken a step further in the study of carbohydrate-binding modules and created variants with novel binding properties by molecular engineering of one such molecule of known 3D-structure. A combinatorial library

Unprecedented genomic diversity of AhR1 and AhR2 genes in Atlantic salmon (Salmo salar L.)

Aryl hydrocarbon receptor (AhR) genes encode proteins involved in mediating the toxic responses induced by several environmental pollutants. Here, we describe the identification of the first two AhR1 (alpha and beta) genes and two additional AhR2 (alpha and beta) genes in the tetraploid species Atlantic salmon (Salmo salar L.) from a cosmid library screening. Cosmid clones containing genomic salmo

Analysis of Gas6 in Human Platelets and Plasma.

Objective - Gas6 is a member of the vitamin K-dependent protein family. Gas6- deficient mice were found to be resistant to thrombosis because of defective platelet function. Mouse Gas6 was demonstrated to be present in platelets and found to be involved in platelet aggregation. The aim of this study was to investigate the presence of Gas6 in human platelets and plasma and determine its role in pla

Calcium increases endocytotic vesicle size and accelerates membrane fission in insulin-secreting INS-1 cells.

In many cells, endocytotic membrane retrieval is accelerated by Ca2+. The effect of Ca2+ on single endocytotic vesicles and fission pore kinetics was examined by measuring capacitance and conductance changes in small membrane patches of insulin-secreting INS-1 cells. In intact cells, elevation of Ca2+ by glucose stimulation induced a 1.8-fold increase in membrane internalisation. This surprisingly

Pollution related effects on immune function and stress in a free-living population of pied flycatcher Ficedula hypoleuca

We investigated whether exposure to heavy metal pollution affected the immune function of individuals in a free living population of a small insectivorous passerine bird, the pied flycatcher Ficedula hypoleuca. We measured humoral immune responses in two study areas: a polluted area in the vicinity of a copper smelter and a control area far from the smelter. Plasma corticosterone level and blood h

Reflections on the Origins of the Polis: An Economic Perspective on Institutional Change in Ancient Greece

From a beginning of small isolated settlements around 1000 B.C., the city-state (polis) emerged in Greece in the course of four centuries as a political, geographical and judicial unit, with an assembly, council, magistrates and written laws. Using a rational-actor perspective, it is shown how this process was driven by competition among the members of the elite. A crucial ingredient was the gradu

Children in families with a severely mentally ill member Prevalence and needs for support.

Background The prevalence of minor children in families with a severely mentally ill member, these children's needs for support and the situation of the spouses were investigated as part of a multi-centre study of the quality of the mental health services in Sweden performed in 1986, 1991 and 1997. Methods The sample was drawn from relatives of compulsorily and voluntarily admitted inpatients to a

Optimisation of pressurised liquid extraction for the determination of p,p'-DDT and p,p'-DDE in aged contaminated Ethiopian soils

The effectiveness of extracting p,p'-DDT and p,p'-DDE from aged contaminated soil samples by means of pressurized liquid extraction (PLE) was evaluated. Two soil samples, which were contaminated more than 10 years ago, were used in the investigation. The static extraction time was optimised and then validated against the total sum of target analytes obtained from multiple sequential extractions. T

Prevalence and risk factors for ischemia, leak, and stricture of esophageal anastomosis: Gastric pull-up versus colon interposition

BACKGROUND: Reports of esophageal anastomotic complications often involve more gastric than colonic reconstructions and are incomplete because of fragmented followup by physicians unfamiliar with the surgical procedure. STUDY DESIGN: Three hundred ninety-three consecutive esophagectomy patients had prevalence and risk factors determined for graft ischemia and anastomotic leak; 363 of these patient

Improved tumor targeting and decreased normal tissue accumulation through extracorporeal affinity adsorption in a two-step pretargeting strategy

Purpose: Evaluation of the possibilities of reducing the accumulation of radiolabeled streptavidin in radiosensitive organs by extracorporeal affinity adsorption (ECAT). Experimental Design: Rats were injected with biotinylated antibody and subjected to removal of the antibodies from the circulation by ECAT 24 h after injection (avidin column). Animals were then injected with In-111-1,4,7,10-tetra

Yolk androgens and the development of avian immunity: an experiment in jackdaws (Corvus monedula).

Maternally derived androgens have been shown to influence offspring phenotype in various ways. In birds, the benefits of prenatal androgen exposure, such as increased competitiveness and accelerated growth in nestlings, have been suggested to be balanced by costs, such as reduced immune function. In this study, we used an integrative approach to examine the influence of yolk androgens on the devel

Protein kinase C and the regulation of the actin cytoskeleton.

Protein kinase C (PKC) isoforms are central components in intracellular networks that regulate a vast number of cellular processes. It has long been known that in most cell types, one or more PKC isoforms influences the morphology of the F-actin cytoskeleton and thereby regulates processes that are affected by remodelling of the microfilaments. These include cellular migration and neurite outgrowt