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1.
Bull Exp Biol Med ; 145(6): 692-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19110552

RESUMO

We studied the effect of high-cholesterol diet and factors inhibiting 3-hydroxy-3-methylglutaryl coenzyme A reductase on the development of liver fibrosis in C57Bl/6 mice with CCl4- or zymosan-induced hepatitis. Feeding a high-cholesterol diet led to a sharp increase in collagen content in the liver tissue of animals with CCl4-induced or zymosan-induced hepatitis. Atorvastatin and calcitriol produced less pronounced fibrogenic effects. Mevalonate partially prevented the development of cholesterol-induced fibrogenesis. High-cholesterol diet led to accumulation of oxysterols, cholesterol esters, and triglycerides and increased the expression of transforming growth factor-beta1 mRNA in liver tissue. Cholesterol-induced potentiation of the fibrogenic response is probably associated with transforming growth factor-beta1 induction due to accumulation of lipids and oxysterols in the liver.


Assuntos
Cirrose Hepática/metabolismo , Fígado/metabolismo , Animais , Atorvastatina , Calcitriol/farmacologia , Ésteres do Colesterol/metabolismo , Colesterol na Dieta/administração & dosagem , Colágeno/metabolismo , Expressão Gênica/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/prevenção & controle , Masculino , Ácido Mevalônico/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Pirróis/farmacologia , Fator de Crescimento Transformador beta1/genética , Triglicerídeos/metabolismo , Zimosan/farmacologia
3.
J Photochem Photobiol B ; 61(1-2): 68-77, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11485850

RESUMO

Irradiation of a complex between N-(5-azido-2-nitrobenzoyl)-N'-(D-biotinyl)-1,2-diaminoethane (I) and streptavidin with light of 313 nm led to the covalent attachment of the photobiotin analogue I to the protein. Streptavidin could also be labelled in the dark with prephotolyzed I. These results indicate that a long-lived reactive intermediate was formed upon irradiation. Moreover, after cleavage of labelled streptavidin with proteinase K this intermediate appears to be covalently attached to the same peptide as the one obtained by direct photoaffinity labelling. An iminosulfurane II derived from the reaction of biotin sulfur atom with aryl nitrene is responsible for the dark-labelling reaction. The photoproduct II converts in an aqueous solution almost completely into N-(5-amino-2-nitrobenzoyl)-N'-(D-(S-oxo)biotinyl)-1,2-diaminoethane (the half-life of II is 10 days).


Assuntos
Biotina/análogos & derivados , Biotina/química , Indicadores e Reagentes/química , Nitrobenzoatos/química , Estreptavidina/química , Estrutura Molecular , Fotoquímica , Fotólise , Fatores de Tempo , Raios Ultravioleta
4.
Nucleosides Nucleotides Nucleic Acids ; 19(8): 1281-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11097058

RESUMO

A new amphiphilic, high-molecular weight poly (N-acryloylmorpholine) (PAcM) polymer has been used to be linked to oligonucleotide chains through a liquid-phase stepwise synthesis. This new conjugate has been investigated for its melting property, nuclease stability and capacity to elicit RNase H activity. Its antisense activity against an HIV-1 target has been also evaluated.


Assuntos
Morfolinas/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Ribonuclease H/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos , Inosina/análogos & derivados , Estrutura Molecular , Peso Molecular , Morfolinas/síntese química , Morfolinas/química , Desnaturação de Ácido Nucleico , Oligonucleotídeos Antissenso/síntese química , Oligonucleotídeos Antissenso/química , Polietilenoglicóis/química , Solubilidade
6.
Biochimie ; 77(4): 227-32, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8589049

RESUMO

The concept of solid-phase synthesis of oligoribonucleotides using T4 RNA ligase and T4 polynucleotide kinase has been proposed and tested with model homo-oligoribonucleotides. The method consists of the immobilization of the first oligomer block at the 3'-terminus on a solid support followed by a chain elongation in the 5'-direction with trinucleoside diphosphates using T4 RNA-ligase and phosphorylation using polynucleotide kinase. Hydrazides of Biogel P-300, Sepharose 4B and cellulose were tested as solid supports for immobilization of initial oligomers. The properties of supports were rated on reactivities of immobilized 5'-phosphorylated oligomers as phosphate donors in the solid phase reactions, hydrodynamical properties and capacity to eliminate donor molecules spontaneously during reactions. Hydrazide of Sepharose 4B appeared to be a more suitable support because of better hydrodynamic properties and highest reactivities of immobilized donors. Saturated concentrations of RNA ligase and polynucleotide kinase and optimal time of joining reaction were determined. In a model experiment ApApA was twice attached to the immobilized hydrazide of Sepharose 4B donor (pA)6pAox. The yield of (Ap)12 was 25%.


Assuntos
Bacteriófago T4/enzimologia , Oligorribonucleotídeos/síntese química , Polinucleotídeo 5'-Hidroxiquinase/química , RNA Ligase (ATP)/química , Animais , Celulose/química , Humanos , Hidrazinas/química , Oligorribonucleotídeos/metabolismo , Fosforilação , Polinucleotídeo 5'-Hidroxiquinase/metabolismo , RNA Ligase (ATP)/metabolismo , Sefarose/química , Fatores de Tempo
7.
Bioorg Khim ; 19(4): 439-54, 1993 Apr.
Artigo em Russo | MEDLINE | ID: mdl-8494567

RESUMO

A method for coupling 2,4-di[alpha-(2-hydroxyethoxy)ethyl] deuteroporphyrin dimethyl ether (IX), DDPOH and its complexes with metals to the 5'- or 3'-end of oligonucleotides was elaborated. In the presence of an oxidizing agent (H2O2), Fe(III)DDP-derivatives of oligonucleotides modified single-stranded DNA. The reaction was strictly site-specific and occurred at two neighbouring guanosine residues. A few types of modification were observed: cross-linking, modification leading to DNA cleavage upon piperidine treatment, and direct chain scission. The total modification yield reached 90%. Covalent attachment of Fe(III)DDP-group to oligonucleotides increased the efficiency of their uptake and the melting temperature of their complementary complexes.


Assuntos
DNA/química , Deuteroporfirinas/química , Metais/química , Oligonucleotídeos/química , Porfirinas/química , Sequência de Bases , Reagentes de Ligações Cruzadas , Dados de Sequência Molecular , Oxirredução
8.
Mol Biol (Mosk) ; 27(1): 64-71, 1993.
Artigo em Russo | MEDLINE | ID: mdl-7683372

RESUMO

It was shown previously that E. coli RNA polymerase in a highly selective manner recognizes and binds 11-14-mere oligodeoxyribonucleotides related to the "-10" region of the nontranscribed DNA strand of bacterial gene promoters. The oligodeoxyribonucleotides cover the Pribnow box with flanking nucleotides up to the transcription start. These affinity oligodeoxyribonucleotides inhibit competitively the transcription of bacterial DNA carried out by E. coli RNA polymerase. The present work has demonstrated that E. coli RNA polymerase is not capable of binding the oligoribonucleotides homologous to the affinity oligodeoxyribonucleotides related to the "-10" area of the spc promoter, but binds the oligoribonucleotides which are complementary to the latter. The oligoribonucleotides with a high affinity for the E. coli RNA polymerase strongly inhibit transcription of the bacterial DNA. Attachment of alkylating groups to the 5'-ends of the affinity oligodeoxy- and oligoribonucleotides provides their covalent binding to the E. coli RNA polymerase subunits. It was shown that the modified affinity 32P-labelled oligodeoxyribonucleotide is covalently bound to the sigma-subunit while the modified affinity 32P-labelled oligoribonucleotide is covalently bound to the beta'beta-subunits of the E. coli RNA polymerase. It is suggested that the affinity oligoribonucleotides can be transcribed from the non-transcribed DNA strand in the region of the open complex and functions presumably as a primer which is splitted later from the nascent RNA or as a regulator of transcription.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/metabolismo , Oligonucleotídeos/metabolismo , Regiões Promotoras Genéticas , Sequência de Bases , Sítios de Ligação , DNA Bacteriano/genética , Escherichia coli/genética , Dados de Sequência Molecular , RNA Bacteriano/genética , Transcrição Gênica
9.
Bioorg Khim ; 18(4): 540-9, 1992 Apr.
Artigo em Russo | MEDLINE | ID: mdl-1503572

RESUMO

Highly effective site-specific photomodification of a DNA-target was carried out with oligonucleotide reagents carrying aromatic azido groups. Oligonucleotide derivatives with a photoactive function R on the 5'-terminal phosphate and at C-5 atom of deoxyuridine were synthesized: R1NH(CH2)3NHpd(TCCACTT) and d(ULNHRCCACTT), where R1 is p-azidotetrafluorobenzoyl, R2 is 2-nitro, 5-azidobenzoyl, R3 is p-azidobenzoyl; LNH = -CH2NH-, -CH2OCH2CH2NH- or -CH2NHCOCH2CH2NH-. The prepared compounds form stable complementary complexes and effect site-specific photomodification of the target DNA. The modification of pentadecanucleotide d(TAAGTGGAGTTTGGC) with the reagents was investigated. Maximum extent of modification strongly depended on the reagent's type, the photoreagent with R1 being the most effective. Whatever the binding site was, this agent provided a 65-70% modification in all cases except LNH = -CH2NH-, when the yield was twice lower. For the reagents bearing R1 the modification sites were identified. Selective modification at the G9 residue was detected in the case of LNH = -CH2OCH2CH2NH- and when a photoactive group was linked to the terminal phosphate.


Assuntos
DNA/química , Autorradiografia , Azidas/química , Sequência de Bases , Cromatografia Líquida de Alta Pressão , DNA/genética , Eletroforese , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Sondas de Oligonucleotídeos , Fotoquímica
10.
Bioorg Khim ; 18(1): 92-9, 1992 Jan.
Artigo em Russo | MEDLINE | ID: mdl-1524588

RESUMO

Diastereomers of oligonucleotide ethyl phosphotriesters were separated by high-performance complementary (affinity) chromatography on a column with the immobilized complementary oligonucleotide. The elution buffer contained 0.18 M K2HPO4, pH 7.5, and 30% acetonitrile. The temperature of the separation was a few degrees lower than Tm of corresponding oligonucleotide complexes. The diastereomers separated completely or partially were: d[GCC(Et)AAACA], d[GCCA(Et)AACA], d[GCAA(Et)ACA], d[GCC(Et)A(Et)AACA], d[GCC(Et)AA(Et)ACA], d[GCCA(Et)A(Et)ACA], d[GCC(Et)A(Et)A(Et)ACA].


Assuntos
Oligonucleotídeos/química , Compostos Organofosforados/química , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Estereoisomerismo , Temperatura
11.
Acta Histochem Suppl ; 42: 293-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1533947

RESUMO

Biopsies of right auricle of human heart have been obtained during open heart surgery from 6 patients aged 23 to 49. The DNA and total protein content have been determined in isolated myocytes by two-wavelength scanning cytophotometry after double staining: Feulgen and naphthol yellow S. In all the biopsies predominant are polyploid hypertrophied myocytes. Both hypertrophied non-degenerating cells and cells with different extent of degenerative changes, primarily of myofibrils and membranes, are present. The highest extent of cell ploidy is in patients belonging to functional class IV according to the classification of New York Heart Association (NYHA); in these cases 72 to 98% of cells have nuclei with 8 c and more DNA content. With an increase in ploidy level, cells grow in size and in protein content, however the rate of this growth is much lower than that of DNA content in cells. There is no direct relation between ploidy and cell degeneration extent and no inverse relation between degeneration extent and ejection fraction.


Assuntos
Valva Mitral/metabolismo , Miocárdio/metabolismo , Adulto , Cardiomegalia/patologia , DNA/metabolismo , Feminino , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Histocitoquímica , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/patologia , Valva Mitral/ultraestrutura , Proteínas Musculares/metabolismo , Miocárdio/ultraestrutura
12.
Farmakol Toksikol ; 54(3): 65-7, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1915830

RESUMO

The method of the quantitative determination of ampicillin in the blood serum and urine on the Soviet-made chromatograph "Milichrom" with an ultraviolet detector and 2 x 62 cm column is described. The conditions of chromatography were as follows: wavelength-210 nm; elution rate-100 microliters/min; analysis time-12 min. The conditions of chromatographic analysis were selected on sorbents Lichrosorb RP-18, Nucleosil S-18 and Silosorb S-18. The given method of ampicillin determination--is characterized by a high specificity, accuracy, the use of small volumes of the blood taken from a finger, the rapidity of making analyses and may be recommended for introduction in the clinical practice for optimization of treating patients with ampicillin.


Assuntos
Ampicilina/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Estudos de Avaliação como Assunto , Humanos , Reprodutibilidade dos Testes
13.
Tsitologiia ; 33(7): 38-50, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1823672

RESUMO

Biopsies from human right auricles were obtained during open heart surgery, prior to valve replacement, from six patients (aged from 20 to 49 years) with rheumatic heart disease. DNA and the total protein contents were measured in isolated myocytes by means of the two wave-length scanning cytophotometry after the double Feulgen and Naphthol yellow S staining procedure. In all the biopsies polyploid hypertrophied myocytes predominate. The hypertrophic, nondegenerated cells and the cells with degenerative changes of varying severity (in the first place, changes of contractile apparatus and membranes) are present. The highest degree of cell ploidy occurs in patients of functional class IV according to the New York Heart Association classification, 72 to 98% of cells displaying octaploid and higher DNA values. With the increase in ploidy of myocytes in series 2c----4c----8c----16c----32c----64c the protein content increases only as 2.0----3.0----5.8----7.8----13.0----16.8. Neither direct correlation between the ploidy level and the degree of cell degeneration, no inverse correlation between the degree of degeneration and the value of ejection fraction was observed.


Assuntos
DNA/metabolismo , Insuficiência da Valva Mitral/patologia , Estenose da Valva Mitral/patologia , Miocárdio/ultraestrutura , Proteínas/metabolismo , Cardiopatia Reumática/patologia , Adulto , Biópsia , Citofotometria , Feminino , Átrios do Coração/metabolismo , Átrios do Coração/ultraestrutura , Humanos , Período Intraoperatório , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/metabolismo , Estenose da Valva Mitral/metabolismo , Miocárdio/metabolismo , Poliploidia , Cardiopatia Reumática/metabolismo
15.
Vopr Med Khim ; 32(6): 55-7, 1986.
Artigo em Russo | MEDLINE | ID: mdl-3811287

RESUMO

Metabolism of chloroquine in microsomes of mice liver tissue was studied in vitro by means of thin-layer and microcolumn liquid chromatographies. Chloroquine was metabolized in the system with liver microsomal monooxygenases. The products of its oxidation, involving side chain and aminoquinoline nucleus, were studied. As the enzymatic system is principally similar in various species, analogous metabolites of chloroquine appear to be produced after oxidation of the substance in the plasmodium microsomal monooxygenase system. Thus, this metabolic pathway is responsible for chloroquine resistance of the malarial parasite.


Assuntos
Cloroquina/metabolismo , Microssomos Hepáticos/metabolismo , Oxigenases de Função Mista/metabolismo , Animais , Biotransformação , Cromatografia em Camada Fina , Técnicas In Vitro , Camundongos , Microssomos Hepáticos/enzimologia
16.
Nucleic Acids Res ; 12(22): 8509-24, 1984 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-6390344

RESUMO

Primer-dependent transcription by E. coli RNA polymerase on T7 promoter A2 has been studied. Synthetic deoxyribonucleotides complementary to the promoter over the region -8...+2 were taken as primers. A ribonucleoside residue was present at the 3'-end of some of these oligonucleotides. The octanucleotide complementary to the region -8...-1 appeared to be an active primer. Oligonucleotides having lengths from 3 to 6 nucleotide residues complementary to the promoter over the region -4...+2 also exhibited primer activity. The latter was some 5-10 times greater in the case of oligonucleotides having a ribonucleoside residue at the 3'-end. Oligonucleotides which on complementary binding do not reach the center of phosphodiester bond synthesis, as well as the decanucleotides (-8...+2) and octanucleotides (-6...+2) of both the ribo- and deoxyribo-series were inactive as primers.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Oligodesoxirribonucleotídeos/síntese química , Oligonucleotídeos/síntese química , Regiões Promotoras Genéticas , Transcrição Gênica , Sequência de Bases , Escherichia coli/genética , Indicadores e Reagentes , Radioisótopos de Fósforo
17.
Tsitologiia ; 23(5): 539-44, 1981 May.
Artigo em Russo | MEDLINE | ID: mdl-7256852

RESUMO

The glycogen content in DNA synthesizing and non-synthesizing hepatocytes has been conducted cytochemically during the rat postnatal development. Within all the periods of investigation, the average glycogen content in DNA synthesizing hepatocytes (phase S) are shown to be lower than that in hepatocytes being in phases G0 and G1. The absolute value of reduction of the glycogen content with diploid mononucleate hepatocytes in S-phase is almost the same for rats of all the age groups examined. The absolute value of reduction of the glycogen content in diploid binucleate hapatocytes in S-phase is twice as much as that in diploid mononucleate hepatocytes being at the same stage of the cell cycle. Regardless of the postnatal development stage and of the total glycogen content in the liver, the glycogen content in DNA non-synthesizing hepatocytes of different ploidy is in conformity with the genome number.


Assuntos
Envelhecimento , DNA/biossíntese , Glicogênio Hepático/análise , Fígado/metabolismo , Animais , Histocitoquímica , Fígado/crescimento & desenvolvimento , Ratos , Espectrometria de Fluorescência
18.
Tsitologiia ; 22(6): 658-65, 1980 Jun.
Artigo em Russo | MEDLINE | ID: mdl-7414693

RESUMO

Using the combined cytochemistry, that allows to determine glycogen and DNA contents, and to localize 3H-thymidine label in one and the same cell, glycogen content was measured in both 3H-TdR-marked and 3H-TdR-non-marked hepatocytes of week-old rats. The vast majority of hepatocytes in a liver population of such rats are mononuclear 3H-TdR-non-marked cells with a 2C DNA content, which corresponds to the diploid chromosome set. The ratio of binuclear hepatocytes with diploid nuclei is in average 0.6%. At one injection of 3H-TdR, 6.6% of hepatocytes are marked in average which are almost exclusively mononuclear cells with 2c to 4c DNA content. In binuclear hepatocytes with two diploid nuclei (2c X 2), the label was seen only in single instances. The average glycogen content in S-phase hepatocytes is aproximately one third of that in hepatocytes that did not start DNA synthesis (G1 and G2 phases). The glycogen content in hepatocytes is seen reducing during S-phase. The glycogen content in G2-phase hepatocytes does not differ from that of hepatocytes before they start DNA synthesis. The availability of glycogen is not necessary for the beginning of S-phase: DNA synthesis in hepatocytes of week-old rats can start and proceed irrespective of the presence of glycogen in these. The glycogen content in binuclear hepatocytes with diploid nuclei that did not start DNA-synthesis is twice as much as in mononuclear hepatocytes before they started DNA synthesis.


Assuntos
DNA/biossíntese , Glicogênio Hepático/metabolismo , Fígado/metabolismo , Animais , Animais Recém-Nascidos , Autorradiografia , Ciclo Celular , Histocitoquímica , Glicogênio Hepático/genética , Ploidias , Ratos
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