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1.
Sci Total Environ ; 566-567: 1289-1296, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27267720

RESUMO

As part of a long-term, peatland-scale sulfate addition experiment, the impact of varying sulfate deposition on bacterial community responses was assessed using 16S tag encoded pyrosequencing. In three separate areas of the peatland, sulfate manipulations included an eight year quadrupling of atmospheric sulfate deposition (experimental), a 3-year recovery to background deposition following 5years of elevated deposition (recovery), and a control area. Peat concentrations of methylmercury (MeHg), a bioaccumulative neurotoxin, were measured, the production of which is attributable to a growing list of microorganisms, including many sulfate-reducing Deltaproteobacteria. The total bacterial and Deltaproteobacterial community structures in the experimental treatment differed significantly from those in the control and recovery treatments that were either indistinguishable or very similar to one another. Notably, the relatively rapid return (within three years) of bacterial community structure in the recovery treatment to a state similar to the control, demonstrates significant resilience of the peatland bacterial community to changes in atmospheric sulfate deposition. Changes in MeHg accumulation between sulfate treatments correlated with changes in the Deltaproteobacterial community, suggesting that sulfate may affect MeHg production through changes in the community structure of this group.


Assuntos
Poluentes Atmosféricos/análise , Bactérias , Microbiota , Sulfatos/análise , Áreas Alagadas , Biodegradação Ambiental , Deltaproteobacteria , Compostos de Metilmercúrio/análise , Minnesota
2.
Neurology ; 62(2): 313-5, 2004 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-14745079

RESUMO

The authors present a study on the association of PRNP and PRND gene polymorphisms with the occurrence and age at onset of Alzheimer's disease (AD). DNA from 79 Polish patients with probable AD and 107 healthy control subjects was studied. The PRNP codon 129 homozygosity seemed to be associated with the occurrence of AD: In AD patients, the percentage of Val/Val and Met/Met genotypes was higher than in the control subjects. A significant difference appeared also between early-onset (<70 years) and late-onset (> or = 70 years) AD patients in the PRND genotypes.


Assuntos
Doença de Alzheimer/genética , Amiloide/genética , Polimorfismo Genético , Príons/genética , Precursores de Proteínas/genética , Idade de Início , Idoso , Doença de Alzheimer/epidemiologia , Apolipoproteínas E/genética , Códon/genética , Análise Mutacional de DNA , Proteínas Ligadas por GPI , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Polônia , Proteínas Priônicas
3.
Gen Physiol Biophys ; 21(2): 115-46, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12236542

RESUMO

Results of an experimental study of volume osmotic flows in a single-membrane osmotic-diffusive cell, which contains a horizontal, microporous, symmetrical polymer membrane separating water and binary or ternary electrolyte solutions are presented. In the experimental set-up, water was placed on one side of the membrane. The opposite side of the membrane was exposed to binary or ternary solutions. As binary solutions, aqueous potassium chloride or ammonia solutions were used, whereas potassium chloride in 0.25 mol x l(-1) aqueous ammonia solution or ammonia in 0.1 mol x l(-1) aqueous potassium chloride solution were used as ternary solutions. Two (A and B) configurations of a single-membrane osmotic-diffusive cell in a gravitational field were studied. In configuration A, water was placed in a compartment above the membrane and the solution below the membrane. In configuration B the position of water and solution was reversed. Furthermore, the effect of amplification of volume osmotic flows of electrolyte solutions in the single-membrane osmotic-diffusive electrochemical cell was demonstrated. The thermodynamic models of the flux graviosmotic and amplification effects were developed, and the volume flux graviosmotic effect for configurations A and B of a single-membrane osmotic-diffusive cell was calculated. The results were interpreted within the conventional instability category, increasing the diffusion permeability coefficient value for the system: concentration boundary layer/membrane/concentration boundary layer.


Assuntos
Amônia/química , Celulose/análogos & derivados , Celulose/química , Eletrólitos/química , Membranas Artificiais , Modelos Químicos , Cloreto de Potássio/química , Simulação por Computador , Difusão , Eletroquímica , Gravitação , Osmose , Pressão Osmótica , Polímeros/química , Reprodutibilidade dos Testes , Reologia/métodos , Sensibilidade e Especificidade , Soluções , Termodinâmica , Água/química
4.
Polim Med ; 31(1-2): 45-52, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11712202

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Soluções/química , Membrana Celular/metabolismo , Difusão , Solução Hipertônica de Glucose/química , Gravitação , Osmose , Permeabilidade , Polímeros , Pressão , Água/química
5.
Polim Med ; 31(3-4): 25-32, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11935936

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Pressão Osmótica , Soluções/química , Difusão , Gravitação , Osmose , Permeabilidade , Polímeros , Propriedades de Superfície
6.
Polim Med ; 31(3-4): 33-41, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11935938

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Pressão Osmótica , Soluções/química , Difusão , Etanol/química , Solução Hipertônica de Glucose/química , Gravitação , Osmose , Permeabilidade , Polímeros , Propriedades de Superfície
7.
Polim Med ; 31(3-4): 42-51, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11935939

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Pressão Osmótica , Soluções/química , Difusão , Etanol/química , Solução Hipertônica de Glucose/química , Gravitação , Osmose , Permeabilidade , Polímeros , Propriedades de Superfície
8.
J Biol Phys ; 26(2): 149-70, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23345718

RESUMO

In this paper the classification ofthe gravitational effects in a passive transmembranetransport is presented. Among these effects there arethe flux and force gravitational effects (fluxgraviosmotic effect, osmotic pressure graviosmoticeffect, flux gravidiffusive effect, osmotic pressuregravidiffusive effect, voltage gravielectric effectand current gravielectric effect). The volume fluxgraviosmotic and solute flux gravidiffusive effectsmodel equations for a single-membrane system areelaborated. These models for binary and ternarynon-electrolyte solutions have been verified using anexperimental data volume and solute fluxes forosmotic-diffusion cell with horizontally mountedmembrane. In the experimental set-up, water was placedon one side of the membrane. The opposite side of themembrane was exposed to binary or ternary solutions ofdensities greater than that of water (aqueous glucoseor glucose-0.2 mole/l aqueous ethanol) and binary andternary solutions of densities larger than that ofwater (aqueous ethanol or ethanol-0.05 mole/l aqueousglucose). These experimental results are interpretedin terms of the convective instability that increasesthe diffusive permeability coefficient of junction:boundary layer/membrane/boundary layer.

9.
Mol Cell Biol ; 19(7): 4866-73, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10373536

RESUMO

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.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA/metabolismo , Anemia de Fanconi/metabolismo , Proteínas Nucleares , Proteínas/metabolismo , Animais , Linhagem Celular Transformada , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi , Proteína do Grupo de Complementação G da Anemia de Fanconi , Proteínas de Grupos de Complementação da Anemia de Fanconi , Humanos , Proteínas/genética , Coelhos
10.
Exp Hematol ; 27(4): 587-93, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10210316

RESUMO

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.


Assuntos
Proteínas de Ciclo Celular , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA , Anemia de Fanconi/genética , Proteínas Nucleares , Mutação Puntual , Biossíntese de Proteínas , Proteínas/genética , Substituição de Aminoácidos/genética , Linhagem Celular , Análise Mutacional de DNA , Anemia de Fanconi/metabolismo , Proteína do Grupo de Complementação C da Anemia de Fanconi , Proteínas de Grupos de Complementação da Anemia de Fanconi , Expressão Gênica , Teste de Complementação Genética , Humanos , Immunoblotting , Linfócitos/química , Fosforilação , Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
11.
Polim Med ; 28(3-4): 11-22, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-10093153

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Polímeros , Soluções/química , Difusão , Modelos Estatísticos , Permeabilidade
12.
Polim Med ; 28(3-4): 23-35, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-10093154

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Polímeros , Soluções/química , Difusão , Gravitação , Teste de Materiais , Permeabilidade , Pressão
13.
Pol Tyg Lek ; 47(24-26): 549-51, 1992.
Artigo em Polonês | MEDLINE | ID: mdl-1282713

RESUMO

Prazosin--a selective blocker of alpha 1-adrenergic receptors--was administered to 30 patients with benign prostatic hypertrophy. Twenty four patients (80%) reported an improvement in voiding and observed more potent urinary stream after the treatment. Average and maximum flow rates increased in 18 patients (60%). Therapy had to be discontinued in 2 patients because of the adverse reactions (hypotension and syncope in one and exacerbation of the coronary disease symptoms in another patient).


Assuntos
Prazosina/administração & dosagem , Hiperplasia Prostática/tratamento farmacológico , Administração Oral , Idoso , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Relação Dose-Resposta a Droga , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/fisiopatologia , Micção/efeitos dos fármacos , Micção/fisiologia , Urodinâmica/efeitos dos fármacos , Urodinâmica/fisiologia
14.
Neuropsychobiology ; 7(3): 122-6, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7231652

RESUMO

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.


Assuntos
Amitriptilina/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Monoaminoxidase/sangue , Fenelzina/uso terapêutico , Amitriptilina/efeitos adversos , Plaquetas/enzimologia , Transtorno Depressivo/enzimologia , Transtorno Depressivo/psicologia , Humanos , Fenelzina/efeitos adversos , Escalas de Graduação Psiquiátrica
16.
Int Urol Nephrol ; 10(1): 15-21, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-649282

RESUMO

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.


Assuntos
Rim/cirurgia , Suturas , Adesivos Teciduais , Bexiga Urinária/cirurgia , Adulto , Idoso , Estudos de Avaliação como Assunto , Feminino , Humanos , Rim/lesões , Cálculos Renais/cirurgia , Nefropatias/cirurgia , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Incontinência Urinária por Estresse/cirurgia
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