Characterization of endothelin-1 and nitric oxide generating systems in corpus luteum-derived endothelial cells

Endothelium-derived endothelin-1 (ET-1) and nitric oxide (NO) are pivotal regulators of corpus luteum (CL) function. To have a better insight into their synthesis and action, members of the ET system (ET-1, ET converting enzyme (ECE-1) isoforms a-d, ETA and ETB receptors) along with NO synthase (NOS) isoforms--endothelial (e)NOS and inducible (i)NOS--were quantified in CL-derived endothelial cells (CLEC). The expression of these genes in microvascular CLEC, obtained by lectin-coated magnetic beads, was compared with cells removed from the luteal microenvironment and maintained in culture for different durations, and with endothelial cells (EC) derived from a large blood vessel (i.e. bovine aortic endothelial cells, BAEC). The profile of gene expression in the different EC types was determined by quantitative real-time PCR. Freshly isolated EC from mid-cycle CL exhibited high ET-1 receptor expression (both ETA and ETB), low ET-1 synthesizing ability (both prepro (pp) ET-1 and ECE-1), but elevated iNOS - the high throughput NOS isoform. The distinct phenotype of CLEC was lost soon after an overnight culture. ETA and ETB receptor levels declined, ppET-1 levels increased while iNOS was reduced. These changes were extenuated during long-term culture of CLEC. The general pattern of gene expression in BAEC and long-term cultured CLEC was similar yet some differences, reminiscent of freshly isolated CLEC, remained: ECE-1c, ETB receptor and NOS isoforms were expressed differently in BAEC as compared with lines of CLEC. This study suggests that the luteal microenvironment is necessary to sustain the selective phenotype of its resident endothelial cells. The inverse relationship between ppET-1 and iNOS observed in freshly isolated CLEC and in cultured cells is physiologically significant and suggests that ET-1 and NO may modulate the production of each other.     

Feeding 2-hydroxy-4-(methylthio)-butanoic acid to periparturient dairy cows improves milk production but not hepatic metabolism

Forty-eight Holstein cows, entering second or later lactation, were utilized to determine the effects of 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on milk production, hepatic lipid metabolism, and gluconeogenesis during the periparturient period. Cows were fed one of 3 diets as TMR starting 21 d before expected calving. These diets contained 0 (the basal diet), 0.09 (+HMB), or 0.18 (++HMB)% HMB. From parturition to 84 DIM, cows were fed diets that contained 0, 0.13, or 0.20% HMB. Prepartum and postpartum dry matter intakes were similar among cows fed the basal diet, +HMB and ++HMB. There was a quadratic effect on milk yield such that cows fed +HMB had the greatest milk yield; yields of milk by cows fed the basal diet and ++HMB were similar. This led to trends for increased yields of 3.5% fat-corrected milk and total solids when cows were fed +HMB. Percentages of fat, protein, and total solids in milk were not affected by treatment. Despite differences in milk yield, calculated energy balance was not affected by treatment. Plasma concentrations of NEFA, beta-hydroxybutyrate, and glucose were not different among treatments. Liver triglyceride content was similar among treatments on d 1 postpartum and was increased for cows consuming +HMB on d 21 postpartum compared with the other dietary treatments. Capacities for metabolism of [1-14C]palmitate by liver slices in vitro were not affected by treatment; however, conversion of [1-14C]propionate to CO2 and glucose decreased as the amount of HMB consumed by cows increased on d 21 postpartum. Cows consuming +HMB had greater days to first ovulation compared with cows consuming the basal diet and ++HMB as measured by plasma progesterone concentrations. These data suggest that adding HMB to low Met diets to achieve a predicted Met supply of approximately 2.3% of metabolizable protein supply is beneficial for increasing milk production but does not appear to benefit hepatic energy metabolism during early lactation.     

Evaluation of the mass spectrometric patterns of volatile liquid anaesthetics to predict the temperature--metal caused decomposition pathway

In this study, prediction of the thermal decomposition pathway of the volatile liquid anaesthetics such as halothane, enflurane and isoflurane in contact with various metal/metal oxides at elevated temperatures has been deduced by evaluating the mass spectrometric fragmentation pattern of each anaesthetic observed in the ionisation process. In the light of the molecular structures and fragmentation components, it was believed that the thermal decomposition pathway of each anaesthetic on metal/metal oxide surface, particularly at higher temperatures, is similar to the ionisation mechanism occurring in the mass spectrometer ionisation process with minor differences for each molecule. The ionisation clusters for each anaesthetic molecule show the most likely fragment and radicals formed in the mass spectrometric ionisation process by considering the isotopic effect. From these clusters, thermal decomposition pathway of the liquid anaesthetics and formation mechanisms of the major halogenated thermal decomposition products have been predicted. It was concluded that the ionisation and thermal decomposition pathway resembles each other, but are not completely similar.     

Einsatz von Mikroemulsionen als Waschsysteme in der Textilveredlung

The Application of Microemulsions as a Washing-System in the Finishing Industry In the textile finishing in many areas dispers systems are been used or develop during the processing. Examples are the dyeing bath for polyester fibers in which hydrophobic dyestuff acts as an dispersion in water. Another example for such a system occurs during washing. In such a case the oil-surfactant-water system changes from a solution of surfactant in water into oil-in-water emulsion as a function of dwelling-time. The present paper discusses the usefulness of a one phase water-oil-surfactant system in textile finishing processes. In detail a physico-chemical characterisation of a many component system consisting of water/hydrophob/amphiphil (surfactant)/electroyte is been needed. The behaviour of such systems is dependent on the chemical structure of the components and of pressure and temperature. Those systems show one-, two- and threephase regions. In this paper evidence will be given that the conditions having the highest degree of efficiency toward cleanness of the textile goods occurs in the one-phase region close to the three phase transition.     

Auslegungskriterien für die Extraktion mit chemischer Reaktion und Flüssigmembran-Permeation

Design criteria for extraction with chemical reaction and liquid membrane permeation. Design criteria for extraction and liquid membrane permeation are discussed and related to these classical extraction columns. Well known models, like the diffusion and the forward mixing model, are used to describe the concentration profile in a column. Mass transfer models for a single globule, like the two-layer and the shrinking core model, are incorporated. The complex chemical interactions on an interface are formulated. A final discussion considers the relevance of the model parameters and their influence on mass transfer.     

Endothelial cell expression of testican mRNA

By screening random cDNAs from a continuous vascular endothelial cell line, EA.hy926, we identified a 5 kb mRNA that is expressed at high levels by this human cell line and by an early passage umbilical vein endothelial cell line. It is detected at lower levels in certain stromal cell lines, but it is not detected in most other cell lines tested, indicating that it represents a differentially expressed function rather than a ubiquitous or housekeeping function. This mRNA was readily detected in samples derived from most human organs as might be expected for a gene expressed in the vascular wall. Sequencing of the 5 kb mRNA reveals its identity with 3.5 kb of previously published testis-derived cDNA sequence called testican (Alliel et al., 1993). Differential expression of this gene by endothelial cells contributes a new perspective on the potential function of testican.     

COBRA-3M: A modified version of COBRA for analyzing thermal-hydraulics in small pin bundles

COBRA-3M, a modified version of COBRA computer code, is most suitable for the analysis of thermal-hydraulics in small pin bundles commonly used in in-reactor or out-of-reactor experiments. It includes detailed thermal models for the fuel pins and duct walls. It can handle nonuniform power distribution across the bundle and/or within a fuel pin. Temperature dependence of material properties and fuel-cladding gap conductance can be treated. Heat generation in the duct walls and the effect of heat loss to the surroundings can also be simulated. COBRA-3M has been used extensively in the design and analysis of TREAT and SLSF experiments.