Biomedical subjects

J Wasik

Publications and source records attributed to J Wasik.

16 recordsLinked to original sources

PubMed2001

[A pressure gravity-diffusive effect for flat polymeric membrane and ternary non-electrolyte solutions].

In this paper the pressure gravidiffusive model equation in a single-membrane osmotic-diffusive cell is elaborated. In this cell the flat, microporous and symmetric polymeric membrane so-called Nephrophane positioned horizontally separated water and binary (aqueous glucose or aqueous ethanol) or ternary (glucose in 0.2 mol.l-1 aqueous ethanol or ethanol in 0.05 mol.l-1 aqueous glucose) non-electrolyte solutions. The calculations of pressure gravidiffusive effects for the configurations A and B of the single-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane and in configuration B--above membrane. The calculated result are interpreted in terms of the convective instability that increases the diffusive permeability coefficient of complex: concentration boundary layer/membrane/concentration boundary layer.

Cell Membrane↗

PubMed2001

[Gravitational osmotic pressure effect for a series of flat polymer membranes positioned horizontally].

In this paper the results of study pressure graviosmotic effect for a double-membrane osmotic-diffusive cell, in which series of two (Ml and M(r)), microporous and symmetrical flat polymeric membranes (Nephrophane and Cellulose IMP-1) separate three compartments (l, m, r) containing the heterogeneous and binary (aqueous glucose or ethanol solutions) or ternary (glucose solutions in 0.75 mole.l-1 aqueous ethanol solution or ethanol solutions in 0.1 mole.l-1 aqueous glucose solution) non-ionic solutions. In this system the solution concentrations fulfill the condition Ckl > Ckm > Ckr. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartment (l and r) fulfill the conditions Vm-->0 and Vl = Vr-->infinity respectively. The calculations of pressure graviosmotic effect for configurations A and B of the double-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane M(r) and water above membrane Ml. In configuration B solution was placed in compartment above membrane Ml and water below membrane Ml. These calculated results are interpreted in terms of the convective instability that increases the diffusive permeability coefficients of complexes: concentration boundary layers (membrane Ml or M(r)) concentration boundary layer.

Diffusion↗

PubMed2001

[Streaming gravity-diffusive effect for a series of two flat polymeric membranes oriented horizontally].

In this paper the results of study flux gravidiffusive effect for a double-membrane osmotic-diffusive cell, in which series of two (Ml and M(r)), microporous and symmetrical flat polymeric membranes (Nephrophane and Cellulose IMP-1). These membranes separate three compartments (l, m, r) containing the heterogeneous and binary (aqueous glucose or ethanol solutions) or ternary (glucose solutions in 0.75 mole.l-1 aqueous ethanol solution or ethanol solutions in 0.1 mole.l-1 aqueous glucose solution) non-ionic solutions. The solution concentrations fulfil the condition Ckl > Ckm > Ckr. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartment (l and r) fulfill the conditions Vm-->0 and Vl = Vr-->infinity respectively. The study of flux gravidiffusive effect for configurations A and B of the double-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane M(r) and water above membrane Ml. In configuration B solution was placed in compartment above membrane Ml and water below membrane Ml. These results are interpreted in terms of the convective instability that increases the diffusive permeability coefficients of complexes: concentration boundary layers/membrane Ml or M(r)/concentration boundary layer.

Diffusion↗

PubMed2001

[Streaming gravity-osmotic effect for a series of two flat polymeric membranes oriented horizontally and ternary non-ionic solutions].

In this paper the results of study flux graviosmotic effect for a double-membrane system, in which two (Ml and M(r)), microporous and symmetrical flat polymeric membranes (Nephrophane and Cellulose IMP-1) separate three compartments (l, m, r) containing the heterogeneous and binary (aqueous glucose or ethanol solutions) or ternary (glucose solutions in 0.75 mole.l-1 aqueous ethanol solution or ethanol solutions in 0.1 mol.l-1 aqueous glucose solution) non-ionic solutions. In this system the solution concentrations fulfill the condition Ckl > Ckm > Ckr. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartment (l and r) fulfill the conditions Vm-->0 and Vl = Vr-->infinity respectively. The calculations of flux graviosmotic effect for configurations A and B of the double-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane M(r) and water above membrane Ml. In configuration B solution was placed in compartment above membrane Ml and water below membrane Ml. These calculated results are interpreted in terms of the convective instability that increases the diffusive permeability coefficients of complexes: concentration boundary layers/membrane Ml or M(r)/concentration boundary layer.

Diffusion↗

PubMed1999

A patient-derived mutant form of the Fanconi anemia protein, FANCA, is defective in nuclear accumulation.

Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome with at least eight complementation groups (A-H). Three FA genes, corresponding to complementation groups A, C, and G, have been cloned, but the function of the encoded FA proteins remains unknown. We recently demonstrated that the FANCA and FANCC proteins bind and form a nuclear complex. In the current study, we identified a homozygous mutation in the FANCA gene (3329A>C) in an Egyptian FA patient from a consanguineous family. This mutant FANCA allele is predicted to encode a mutant FANCA protein, FANCA(H1110P), in which histidine 1110 is changed to proline. Initially, we characterized the FANCA(H1110P) protein, expressed in an Epstein Barr virus (EBV)-immortalized lymphoblast line derived from the patient. Unlike wild-type FANCA protein expressed in normal lymphoblasts, FANCA(H1110P) was not phosphorylated and failed to bind to FANCC. To test directly the effect of this mutation on FANCA function, we used retroviral-mediated transduction to express either wild-type FANCA or FANCA(H1110P) protein in the FA-A fibroblast line, GM6914. Unlike wild-type FANCA, the mutant protein failed to complement the mitomycin C sensitivity of these cells. In addition, the FANCA(H1110P) protein was defective in nuclear accumulation in the transduced cells. The characteristics of this mutant protein underscore the importance of FANCA phosphorylation, FANCA/FANCC binding, and nuclear accumulation in the function of the FA pathway.

Amino Acid Substitution↗

PubMed1999

Fanconi anemia proteins FANCA, FANCC, and FANCG/XRCC9 interact in a functional nuclear complex.

Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome with at least eight complementation groups (A to H). Three FA genes, corresponding to complementation groups A, C, and G, have been cloned, but their cellular function remains unknown. We have previously demonstrated that the FANCA and FANCC proteins interact and form a nuclear complex in normal cells, suggesting that the proteins cooperate in a nuclear function. In this report, we demonstrate that the recently cloned FANCG/XRCC9 protein is required for binding of the FANCA and FANCC proteins. Moreover, the FANCG protein is a component of a nuclear protein complex containing FANCA and FANCC. The amino-terminal region of the FANCA protein is required for FANCG binding, FANCC binding, nuclear localization, and functional activity of the complex. Our results demonstrate that the three cloned FA proteins cooperate in a large multisubunit complex. Disruption of this complex results in the specific cellular and clinical phenotype common to most FA complementation groups.

Animals↗

PubMed1998

[Calculation of the concentration Rayleigh number for isothermal transport processes across a polymeric membrane by a method for measuring diffusion flux in three component non-electrolytic solutions].

A method of determination critical value of concentration Rayleigh Number ((Rci)lim.) in isothermal membrane transport processes of three component non-electrolyte solutions was worked out. The method based on the derived in the paper equation, which include membrane transport coefficients (hydraulic permeability, reflection and diffusive permeability coefficients), solution parameters (viscosity coefficient, density and diffusion coefficient in solution). In order to experimental verification of these method the transport coefficients of symmetric flat polymeric membrane, parameters of solutions and diffusive flux for glucose solution in 0.2 mole/l aqueous ethanol solution were determined. Experiments were carried out by osmotic-diffusive single-membrane double-cell system. One cell in all experiments was filled with pure water while the other with the examined solutions. The experimental critical value of concentration Rayleigh Number (RCi)lim. = 1799 is comparable with theoretical critical value of thermal Rayleigh Number (TT)lim. = 1707.

Diffusion↗

PubMed1998

[Gravity-osmotic pressure effect for flat polymeric membranes and three-component non-electrolyte solutions].

In this paper the classification of the gravitational effects in a passive transmembrane transport is presented. Among these effects there are the flux (flux graviosmotic effect, flux gravidiffusive, current gravielectric effect) and force (pressure graviosmotic effect, pressure gravidiffusive effect, voltage gravielectric effect) gravitational effects. The pressure graviosmotic effect model equation in a single-membrane system is elaborated. In this system the flat, microporous and symmetric polymeric membrane (Nephrophan) positioned horizontally separated water and binary (aqueous glucose) or ternary (glucose-0.2 mole/l) aqueous ethanol) non-electrolyte solutions. The calculations of pressure graviosmotic effects for two (A and B) configurations of the single-membrane system were elaborated. In configuration A solution was placed in compartment below membrane and in configuration B--above membrane. These calculated results are interpreted in terms of the convective instability that increases the diffusive permeability coefficient of complex: boundary layer/membrane/boundary layer.

Diffusion↗

PubMed1981

Relationship between response to phenelzine and MAO inhibition in a clinical trial of phenelzine, amitriptyline and placebo.

This report examines the hypothesis that for phenelzine to be more effective than placebo it is necessary to achieve at least 80% inhibition of platelet MAO activity. This hypothesis was examined in the context of a double-blind comparison of phenelzine, amitriptyline and placebo in depressed patients. When phenelzine became significantly more effective than placebo at 4 weeks, the average MAO inhibition was 85%. By the 5th week, with MAO inhibition greater than 90%, phenelzine was significantly more effective than amitriptyline. A highly significant correlation was noted between improvement and MAO inhibition within the phenelzine group.

Amitriptyline↗

PubMed1978

Preliminary evaluation of the Polish tissue adhesive "Chirurcoll/Polfa" in urology.

During the past two years, from June 7, 1974 to August 9, 1976, the authors used the Polish tissue adhesive "Chirurcoll/Polfa" in 60 operated patients. The operations were performed on the solitary kidney, on the kidneys of staghorn calculi, in fixation of a floating kidney and, fixation and elevation of the bladder in women with urinary stress incontinence. In all cases the postoperative course was smooth and the results of operation were satisfactory. None of the patients were re-operated and histological examinations were not performed.

Adult↗

PubMed1978