Cloning and expression of hbves, a novel and highly conserved mRNA expressed in the developing and adult heart and skeletal muscle in the human

bves is a novel mRNA expressed in the developing heart in chick and mouse. Here we describe hbves, the human homolog of chick and mouse bves. Northern and dot blot analyses reveal restricted expression in the heart and skeletal muscle in the embryo and adult. BLAST searches of the NCBI databases confirm that hbves is novel. Portions of the sequence are an exact match with genomic PAC 52202, which localizes to Chromosome (Chr) 6q21. Presumably, these matches and intervening sequences match the intron-exon borders of the gene. Computer conformation analysis of the derived amino acid predicts three transmembrane helices with an extracellular C-terminus that is conserved in chick, mouse, and human. bves is highly conserved among all three species at the amino acid level with 75% identity and 92% similarity. Received: 15 February 1999 / Accepted: 29 April 1999     

Utilization of (E)-2-butenoate (Crotonate) by Clostridium kluyveri and some other Clostridium species

Clostridium La 1 obtained from a Clostridium kluyveri culture was compared with a typical C. kluyvery strain (DSM 555). The former grows on crotonate and is unable to use ethanol-acetate as carbon sources. The latter grows on crotonate only after long adaptation periods. Resting cells of both strains show also pronounced differences in the fermentation of crotonate. This holds even for C. kluyveri grown on crotonate. Besides several other differences the most striking is that there is no hybridization between the DNA of both strains.Crotonate seems not to be a very special carbon source since C. butyricum and C. pasteurianum grow on crotonate medium supplemented by peptone and yeast extract.Non Standard Abbreviations EA-medium ethanol and acetate as carbon source - C-medium crotonate as carbon source - DSM Deutsche Sammlung von Mikroorganismen     

The rate of rhodopsin phosphorylation in isolated rentinas of frog and cattle.

Phosphorylation of rhodopsin has been measured in isolated retinas incubated with 32P-phosphate under physiological conditions. The half-time of the light-induced phosphorylation was found to be approximately 2 min with frog retinas at 21 degrees C, and in the order of 1--2 min with cattle retinas at 36 degrees C. It is suggested by this slow rate that the phosphorylation reaction is not directly involved in the chain of events which lead from absorption of a photon to excitation of the photoreceptor cells but may perhaps have a regulatory function in controlling light/dark adaptation.     

Membrane currents of rat satellite cells attached to intact skeletal muscle fibers

Muscle satellite cells play an important role in the postnatal growth of skeletal muscle and in the regeneration of damaged muscle during adult life. Little is known about the physiological properties of satellite cells in their dormant state as they lie adjacent to the intact muscle fibers, underneath the basement membrane. Our recent experiments, using patch clamp techniques, indicate that no tight electrical coupling is present between satellite cells and the muscle fiber dissociated from rat flexor digitorum brevis. Satellite cells possess sodium channels with low sensitivity to tetrodotoxin and at a much lower density than muscle. In addition, satellite cells are insensitive to acetylcholine (ACh) for at least 24 hr after having been removed from the animal, even when detached from their muscle fiber. However, we could measure ACh-evoked currents from satellite cells 48-72 hr in culture, indicating that ACh sensitivity develops with time.     

In situ biochemical studies of intestinal alkaline phosphatase in normal and phosphate-depleted rats by microdensitometry

A quantitative microdensitometric study has been designed to characterize in situ intestinal brush border-bound alkaline phosphatase of rat duodenal villosities. Intestinal slices were incubated with beta-glycerophosphate as substrate. Free phosphate liberated was precipitated in presence of a lead reagent as lead sulfide. The precipitate was quantified in situ by scanning and integrating microdensitometry. Kinetic parameters of the reaction were determined at 37 degrees C, pH 8.8, in the middle part of the villosities. Apparent Michaelis constant (Km) for beta-glycerophosphate was found to be 8.16 +/- 0.56 mM (mean +/- S.E.). Maximal enzyme activation was obtained at pH 8.5. Maximal inhibition of enzyme activity was observed in the presence of L-phenylalanine (30 mM) or theophylline (5 mM). Along the villosity axis, enzyme activity rose from the crypt up to the midportion of the villosity and finally decreased at the tip region. In phosphate-depleted rats, enzyme activity was increased in all portions of the villosity, with conservation of the same activity gradient. In this situation, kinetic analysis showed a marked decrease of Km, i.e. 4.56 +/- 0.39 mM (mean +/- S.E.) as compared to normal rats.     

Finite element simulation of interactions between pelvic organs: Predictive model of the prostate motion in the context of radiotherapy

The setting up of predictive models of the pelvic organ motion and deformation may prove an efficient tool in the framework of prostate cancer radiotherapy, in order to deliver doses more accurately and efficiently to the clinical target volume (CTV). A finite element (FE) model of the prostate, rectum and bladder motion has been developed, investigating more specifically the influence of the rectum and bladder repletions on the gland motion. The required organ geometries are obtained after processing the computed tomography (CT) images, using specific softwares. Due to their structural characteristics, a 3D shell discretization is adopted for the rectum and the bladder, whereas a volume discretization is adopted for the prostate. As for the mechanical behavior modelling, first order Ogden hyperelastic constitutive laws for both the rectum and bladder are identified. The prostate is comparatively considered as more rigid and is accordingly modelled as an elastic tissue undergoing small strains. A FE model is then created, accounting for boundary and contact conditions, internal and applied loadings being selected as close as possible to available anatomic data.The order of magnitude of the prostate motion predicted by the FE simulations is similar to the measurements done on a deceased person, accounting for the delineation errors, with a relative error around 8%. Differences are essentially due to uncertainties in the constitutive parameters, pointing towards the need for the setting up of direct measurement of the organs mechanical behavior.     

Effect of partial pressure of CO2 on the production of thermostable α-amylase and neutral protease by Bacillus caldolyticus

Controlling the concentration of dissolved oxygen is a standard feature in aerobic fermentation processes but the measurement of dissolved CO₂ concentrations is often neglected in spite of its influence on the cellular metabolism. In this work room air and room air supplemented with 5 and 10% carbon dioxide were used for aeration during the cultivation of the thermophilic microorganism Bacillus caldolyticus (DSM 405) on starch to produce α-amylase (E.C. 3.2.1.1) and neutral protease (E.C. 3.4.24.27/28). The increased CO₂ concentrations resulted in a 22% raise in activity of secreted α-amylase and a 43% raise in protease activity when compared with aeration with un-supplemented room air. There was no effect on the final biomass concentration. Furthermore, the lag-phase of fermentation was reduced by 30%, further increasing the productivity of α-amylase production. Determinations of dissolved CO₂ in the culture broth were conducted both in situ with a probe as well as using exhaust gas analysis and both the methods of quantification showed good qualitative congruence.