Search results for "biophysic"
showing 10 items of 3565 documents
Computer-assisted interpretation of flow cytometry data in hematology.
1996
A computer program has been developed for computer-assisted diagnosis (including subclassification) of flow cytometry data of acute leukaemias and non-Hodgkin lymphomas by means of artificial intelligence. The knowledge base for the system has been formulatedas semantic networks that describe physiological hematopoiesisas well as the pathological situation (eg., aberrant antigen expression) of hematological disorders. The semantic networks reflect the hierarchy of cells and their occurrence in diseases, the normal and pathological antigen expression patterns of cells, cell maturation, and the frequency of cell populations in normal blood and bone marrow. Using these semantic networks, the d…
BMP-2 and bFGF release and in vitro effect on human osteoblasts after adsorption to bone grafts and biomaterials.
2012
Objectives Combination of scaffolds and growth factors is a promising option for several clinical problems in bone biomaterials. Simplified growth factor loading by adsorption from aqueous solution is one important option for this technology. We evaluated the adsorption followed by PBS rinsing, release and biological effect of transient loading with basic fibroblast growth factor (bFGF) and bone morphogenic protein 2 (BMP-2) on fresh frozen bone, processed bone matrix, collagen, and a ceramic material with immunofluorescence, enzyme-linked immunosorbent assay (ELISA), and qRT-PCR. Materials and methods The study consisted of three in vitro experiments (immunofluorescence, ELISA, and qRT-PCR…
Motor problems in children with early-treated congenital hypothyroidism: A matter of failing cerebellar motor control?
1998
This study addresses the question of whether "clumsiness" in children with early treated Congenital Hypothyroidism (CH) might be attributable to cerebellar dysfunction. CH is known to affect rapid perinatal growth of the cerebellum. If this would affect the supposed motor timing function of the cerebellum this should be especially reflected by difficulty in producing fast aiming movements. An experiment was devised in which children made sequences of fast, goal directed movements in order to examine two aspects of fast voluntary movements that are known to be affected by cerebellar injury: dysmetria and dysdiadochokinesis. Three groups of children between the ages of 9 and ii participated: …
Intestinal filtration as a consequence of increased mucosal hydraulic permeability
1980
Two mechanisms have been proposed to explain the secretory action of laxative compounds in the intestine: 1. increase of the intracellular amount of cyclic adenosine monophosphate due to stimulation of the adenylate cyclase system and 2. inhibition of intestinal transfer processes, in particular the Na,K-ATPase activated sodium absorption. In a set of in vivo and in vitro experiments in rat colon it could be demonstrated that dihydroxy bile acids (deoxycholate) and diphenolic laxatives (oxyphenisatin) enhance the hydraulic permeability of the mucosal tissue. The permeability changes take place--and there is good experimental evidence--at the zonulae occludentes which bind the epithelial cel…
The use of ultrasound to study muscle–tendon function in human posture and locomotion
2013
Analysis of human movement has traditionally relied on measures such as kinematics, kinetics and electromyography. These measures provide valuable information about movement performance and make it possible to draw inferences about muscle and tendon function. Musculoskeletal models are also used frequently to examine the relationship between joint kinematics and muscle-tendon behaviour, and have provided important insights into both healthy and clinical gait. However, muscles interact with compliant tendons during movement, which complicates interpretation of muscle and tendon function based on external measures such as joint kinematics. Accordingly, methods have been developed that enable …
Cost-effectiveness analysis of robot-assisted vs. open partial nephrectomy
2017
Background The cost-effectiveness of robot-assisted partial nephrectomy (RAPN) vs. the open procedure is not established. Methods We estimated in-hospital complications and the cost of RAPN vs. open partial nephrectomy (OPN) using an economic model. Costs incurred both intraoperatively and in hospital were considered. US data were extracted from existing literature. Results Mean in-hospital costs were $14,824 (95% CI $13,368-$16,898) for RAPN and $15,094 (95% CI $13,491-$17,140) for OPN. Complications after RAPN occurred in 23.3% (95% CI 20.0-25.8%) and after OPN in 36.1% (95% CI 35.6-36.6%) of the patients. In a sensitivity analysis, limited centre experience was associated with relevant i…
Cromakalim inhibits electrically-evoked [3H]acetylcholine release from a tube-preparation of the rat isolated trachea by an epithelium-dependent mech…
1993
Rat isolated tracheae were labelled by incubation with [3H]choline to measure the tritium efflux elicited by electrical stimulation of the extrinsic parasympathetic nerves in vitro. Stimulated tritium efflux reflects the neuronal release of newly synthesized acetylcholine; the effects of potassium channel openers on the stimulated tritium efflux were investigated. In tracheae opened longitudinally neither cromakalim nor its 3S,4R-enantiomer, BRL 38227, reduced the stimulated tritium efflux, whereas in intact tube-preparations cromakalim (0.01-1 mumol/l) mediated a concentration-dependent inhibition. The inhibitory effect of 1 mumol/l cromakalim was prevented by 0.1 mumol/l glibenclamide. Li…
Ultrastructural evidence for protection of the outer hair cells of the inner ear during intense noise exposure by application of the organic calcium …
1999
Outer hair cells could be protected during intense noise exposure by the application of the calcium channel blocker diltiazem given before and after noise treatment. After various experimental approaches, the ultrastructural morphology was analysed for the different animal populations in the basal part of the second turn of the cochlea, which was the most destroyed area after an acute noise trauma caused by a gun shot (sound pressure at the ear drum 156 dB, frequency maximum between 4 and 6 kHz). Compared to untreated control specimens (experimental animal group I), the outer hair cells in the basal part of the second turn of the cochlea were mostly destroyed without any diltiazem applicati…
Muscle adenylate kinase in Duchenne muscular dystrophy
1986
Abstract On the basis of electrophoretic and enzyme inhibition studies it was postulated that an aberrant adenylate kinase occurs in muscle and serum of patients with Duchenne muscular dystrophy (Schirmer, R.H. and Thuma, E. (1972) Biochim. Biophys. Acta 268, 92–97; Hamada, M. et al. (1981) Biochim. Biophys. Acta 660, 227–237; Hamada et al. (1985) J. Biol. Chem. 260, 11595–11602. On the basis of the following results we conclude that Duchenne muscular dystrophy patients do not possess an unusual adenylate kinase isoenzyme. (1) In muscle biopsies from five Duchenne patients, the electrophoretic mobility of adenylate kinase and the inhibition of the enzyme by P 1 , P 5 -di(adenosine-5′)pentap…
Magnesium metabolism in type 2 diabetes mellitus, metabolic syndrome and insulin resistance
2007
Type 2 diabetes is characterized by cellular and extracellular Mg depletion. Epidemiologic studies showed a high prevalence of hypomagnesaemia and lower intracellular Mg concentrations in diabetic subjects. Insulin and glucose are important regulators of Mg metabolism. Intracellular Mg plays a key role in regulating insulin action, insulin-mediated-glucose uptake and vascular tone. Reduced intracellular Mg concentrations result in a defective tyrosine-kinase activity, post-receptorial impairment in insulin action, and worsening of insulin resistance in diabetic patients. Mg deficit has been proposed as a possible underlying common mechanism of the "insulin resistance" of different metabolic…