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A mathematical model for measuring blood flow in skeletal muscle with the microdialysis ethanol technique

A theoretical analysis of the microdialysis ethanol technique in skeletal muscle is presented, and a model governing the transport of ethanol from the microdialysis probe to the capillaries in the muscle tissue is proposed. The model is derived under the assumption of a steady-state situation, and an analytical solution is found for the outflow-to-inflow ratio of ethanol in the perfusate. Theoreti

The inverted chevron plot measured by NMR relaxation reveals a native-like unfolding intermediate in acyl-CoA binding protein

The folding kinetics of bovine acyl-CoA binding protein was studied by N-15 relaxation dispersion measurements under equilibrium conditions. Relaxation dispersion profiles were measured at several concentrations of guanidine hydrochloride (GuHCl). The unfolding rate constant (k(u)) was determined under conditions favoring folding, for which the folding rate constant (k(f)) dominates the relaxation

How do middle-aged patients conceive exercise as a form of treatment for knee osteoarthritis?

Purpose. To describe conceptions, as registered by a semi-structured interview, of exercise as treatment among sixteen middle-aged patients with moderate to severe knee osteoarthritis. Method. Sixteen patients ( aged 39 - 64) with symptomatic, radiographic knee osteoarthritis and previous participants in an exercise intervention, were interviewed. The qualitative data obtained were analysed using

Luminescence study of pure and Fe- or Mo-doped ZnWO4 crystals

ZnWO4, ZnWO4 : Fe and ZnWO4 : Mo crystals were investigated by the methods of time-resolved spectroscopy in the temperature range of 4.2-300 K. It is shown that the Mo and Fe impurities significantly reduce the light yield of ZnWO4. The main 2.5 eV emission of ZnWO4 and the 1.77 eV emission band of ZnWO4 : Mo are shown to originate from the triplet excited state of the WO6 and MoO6 complex, respec

Immunohistochemical localization and vascular effects of vasoactive intestinal polypeptide in skeletal muscle of the cat

Scattered vasoactive intestinal polypeptide (VIP)-immunoreactive nerves were found in the striated muscle of the hind limb of the cat, where they usually were associated with small blood vessels. VIP-immunoreactive nerves were also demonstrated in the sciatic nerve; after ligation an abundance of intensely immunoreactive VIP fibres were seen proximal to the ligation. Intraarterial infusion of VIP

Light regulation of the Arabidopsis respiratory chain. Multiple discrete photoreceptor responses contribute to induction of type II NAD(P)H dehydrogenase genes

Controlled oxidation reactions catalyzed by the large, proton-pumping complexes of the respiratory chain generate an electrochemical gradient across the mitochondrial inner membrane that is harnessed for ATP production. However, several alternative respiratory pathways in plants allow the maintenance of substrate oxidation while minimizing the production of ATE We have investigated the role of lig

Analysis of atrioventricular plane movements by Doppler tissue imaging and m-mode in children with atrial septal defects before and after surgical and device closure.

Our objective was to compare the effects of surgical and device closure of atrial septal defects (ASDs) on atrioventricular plane function. In healthy individuals, both short- and long-axis motion contribute to ventricular pump function. Short-axis function (i.e., the amplitude and velocity of atrioventricular plane movements) may be evaluated by M-mode and Doppler tissue imaging. The study group

A Floquet-Bloch Decomposition of Maxwell's Equations Applied to Homogenization

Using Bloch waves to represent the full solution of Maxwell's equations in periodic media, we study the limit where the material's period becomes much smaller than the wavelength. It is seen that for steady state fields, only a few of the Bloch waves contribute to the full solution. Effective material parameters can be explicitly represented in terms of dyadic products of the mean values of the no

Anatomy of the inferior interatrial route in humans

Aims To explore the morphology of the proximal coronary sinus (CS) and the surrounding tissues in order to identify possible routes for interatrial conduction. Method Specimens containing interatrial septum and proximal CS were taken from 21 necropsied hearts and sliced into 10-mu m thick parallel histological sections in 1-mm steps starting from the valve plane, up to the atrial. roof (40-80 sect

Probing stability of the modular thermostable xylanase Xyn10A,

The thermophilic bacterium Rhodothermus marinus produces a modular xylanase (Xyn10A) consisting of two N-terminal carbohydrate-binding modules (CBMs), followed by a domain of unknown function, and a catalytic module flanked by a fifth domain. Both Xyn10A CBMs bind calcium ions, and this study explores the effect of these ions on the stability of the full-length enzyme. Xyn10A and truncated forms t

A comparison between the combustion of natural gas and partially reformed natural gas in an atmospheric lean premixed turbine-type combustor

A small-scale combustor was set up to analyze the combustion of natural gas and two mixtures of partially reformed natural gas. The partially reformed mixtures can be formed using biomass to feed the endothermic reforming reactions. Before combusting these mixtures in a gas turbine, experimental work was done on a primary zone combustion chamber to examine the combustor behavior when switching fro

Postnatally disturbed pancreatic islet cell distribution in human islet amyloid polypeptide transgenic mice

Objective: Islet amyloid polypeptide (IAPP)/amylin is produced by the pancreatic islet beta-cells, which also produce insulin. To study potential functions of IAPP, we have generated transgenic mice overexpressing human IAPP (hIAPP) in the beta-cells. These mice show a diabetic phenotype when challenged with an oral glucose load. In this study, we examined the islet cytoarchitecture in the hIAPP m

Monolithic macroporous albumin/chitosan cryogel structure: a new matrix for enzyme immobilization.

A novel monolithic macroporous material was developed by cross-linking hen egg albumin (HEA) and chitosan with glutaraldehyde at subzero temperatures. A macroporous cryogel structure allowed efficient mass transport of solutes within the material. In one application, albumin was partially replaced with active enzymes (glucose oxidase and horseradish peroxidase) resulting in the production of macro

Construction of polyamine-modified uridine and adenosine derivatives-evaluation of DNA binding capacity and cytotoxicity in vitro

We here report the synthesis of the two polyamine-based nucleoside derivatives 5-{[bis-(3-aminopropyl)amino]acetamido-1-propynyl}uridine and 2-{[bis-(3-aminopropyl)amino]-acetamido-1-propynyl}adenosine. The various polyamine derivatives have been used in thermal melting analysis using DNA from herring testes, and in cellular studies using four different cell lines. The compounds were all found to

Morphological and life history responses to predators in larvae of seven anurans

Amphibian larvae often face two major sources of mortality: pond desiccation and predation. Tadpoles of seven anuran species with different preferences for type of breeding habitat, on a hydroperiod scale, were tested for responses to the presence of predators by raising them experimentally in the presence and absence of a separately caged invertebrate predator that was fed on conspecific tadpoles

A framework for the study of genetic variation in migratory behaviour

Evolutionary change results from selection acting on genetic variation. For migration to be successful, many different aspects of an animal's physiology and behaviour need to function in a co-coordinated way. Changes in one migratory trait are therefore likely to be accompanied by changes in other migratory and life-history traits. At present, we have some knowledge of the pressures that operate a

Videomanometric aspects of pharyngeal constrictor activity

Pressure changes were registered with videomanometry (simultaneous manometry and barium swallow) in the pharynx and in the pharyngoesophageal segment (PES) during swallowing. A considerable longitudinal asymmetry was found. Peak pressure was highest in the PES, lower in the inferior constrictor area, and lowest at the level of the tongue base. The rate of pressure rise was highest at the level of