Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Tsitol Genet ; 38(3): 46-51, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15619988

RESUMO

The influence of culture density and genotype on the polyteny degree of giant chromosomes (PDC) in Drosophila melanogaster was investigated. The reliable depression of the polytene chromosomes endoreduplication function under increased culture density was revealed. The essential dependence of the PDC on the genotype was shown. Correlation between the PDC and the number of adaptive features was established. The certain parallelism between the increased heterosis effect on the number of quantitative characters and the superiority of the hybrids above the inbred lines on the PDC in conditions of high culture density was found out. The sex-dependent distinctions and maternal effect at the inheritance of the PDC in drosophila were shown.


Assuntos
Adaptação Fisiológica/genética , Cromossomos , Drosophila melanogaster/genética , Hibridização Genética , Endogamia , Animais , Cromossomos/genética , Cromossomos/ultraestrutura , Drosophila melanogaster/crescimento & desenvolvimento , Genótipo , Masculino , Glândulas Salivares/ultraestrutura
2.
Genetika ; 40(9): 1209-14, 2004 Sep.
Artigo em Russo | MEDLINE | ID: mdl-15559148

RESUMO

The effect of heterosis was studied in several quantitative traits of clone breed and interbreed silkworm hybrids exposed to electromagnetic irradiation (lambda = 1.6 cm, power density 700 microW/cm2) during postdiapause embryonic development. The influence of the type of reproduction on the manifestation of irradiation effects in the next generation was also examined. In hybrids, the resistance to low-intensity high-frequency irradiation was higher than in the parental forms. Unlike the latter, the hybrids showed no significant modification of the traits after the exposure to electromagnetic irradiation. In the second generation, the modifying effect of irradiation is retained in the case of parthenogenetic silkworm development but not after mating.


Assuntos
Bombyx/efeitos da radiação , Vigor Híbrido/efeitos da radiação , Hibridização Genética , Característica Quantitativa Herdável , Animais , Bombyx/genética , Bombyx/fisiologia , Campos Eletromagnéticos , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Desenvolvimento Embrionário/efeitos da radiação , Vigor Híbrido/genética , Endogamia , Larva , Partenogênese/genética , Partenogênese/fisiologia , Partenogênese/efeitos da radiação , Reprodução/genética , Reprodução/fisiologia , Reprodução/efeitos da radiação
3.
Tsitol Genet ; 37(6): 41-6, 2003.
Artigo em Russo | MEDLINE | ID: mdl-15067945

RESUMO

Activity of polytene chromosome puffs at the 0-hour prepupae stage and bioelectric properties of cellular nuclei of salivary glands were investigated under the influence of the hormone 20-OH-ecdysone in vitro in highly inbred selected lines LA (low activity) and HA (high activity) and their F1 hybrids LA x HA and Ha x LA. The inadaptive line LA differs from the line HA by the smaller size of the puffs. The hybrids exceed the best parental line by the size of the majority of the investigated puffs. In the course of investigation of F1 hybrids Ha x LA chromosomes the phenomenon of heteropuffing has been revealed at the asinapsis sites. In vitro impact of ecdysone increases the electrokinetic potential of cellular nuclei; in hybrids this effect expressed more strongly than in parental lines. The data obtained indicate genetic differences in puffing activity in Drosophila polytene chromosomes as a result of inbreeding, destabilizing selection and heterosis effect, and they also confirm the correlation of bioelectric properties of the nuclear genome with regulation of genetic activity of a cellular nucleus.


Assuntos
Núcleo Celular/fisiologia , Cromossomos/fisiologia , Drosophila melanogaster/genética , Ecdisterona/farmacologia , Heterozigoto , Animais , Núcleo Celular/efeitos dos fármacos , Mapeamento Cromossômico , Drosophila melanogaster/efeitos dos fármacos , Eletrofisiologia , Feminino , Hibridização Genética , Glândulas Salivares/citologia , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/fisiologia
4.
Genetika ; 38(12): 1621-5, 2002 Dec.
Artigo em Russo | MEDLINE | ID: mdl-12575446

RESUMO

The effects of the Bar (B) and white (w) mutations on the expressiveness of the character vestigial (vg) and the degree of polyteny of salivary gland giant chromosomes were studied in Drosophila melanogaster. Either mutation changed both the expressiveness of vestigial and the degree of chromsome polyteny. A negative association between the vg expressiveness and the degree of chromosome polyteny was revealed and proved to be stronger in females than in males. The parameters under study were shown to differ between females and males.


Assuntos
Cromossomos , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas Nucleares/genética , Animais , Feminino , Expressão Gênica , Genótipo , Masculino , Mutação , Glândulas Salivares/fisiologia
5.
Bioelectromagnetics ; 22(2): 106-11, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11180256

RESUMO

The influence of an alternating (50 Hz) electric field (5--110 V/cm) on the state of human buccal epithelium cells was studied by the methods of intracellular microelectrophoresis, heterochromatin staining with orcein, and indigo carmine staining for viability and membrane integrity evaluations. Electric field exposure induced an increase in electrophoretic mobility of cell nuclei, decreased numbers of heterochromatin granules near the inner membrane of cell nucleus, and induced cell membrane damage; but cell viability was conserved. Nuclear and cell membrane properties varied with electric field strength and age of the donors. The data obtained are interpreted as evidence of electric field induced activation of the functional state of nuclei.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Mucosa Bucal/metabolismo , Adulto , Idoso , Envelhecimento/metabolismo , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Bochecha , Células Epiteliais/metabolismo , Feminino , Heterocromatina/metabolismo , Humanos , Técnicas In Vitro , Cinética , Pessoa de Meia-Idade , Mucosa Bucal/citologia
7.
Genetika ; 35(7): 898-902, 1999 Jul.
Artigo em Russo | MEDLINE | ID: mdl-10519068

RESUMO

Effects of culture density on expressivity of character eyeless and polyteny of giant chromosomes were studied in Drosophila melanogaster. Larval crowding was shown to significantly reduce eye facets. The expression of eyeless was sex-dependent: in females, this character was expressed more strongly than in males. Larval crowding resulted in a decrease of chromosome polyteny in larval salivary glands. A strong negative correlation was established between the expressivity of eyeless and the degree of giant chromosome polyteny.


Assuntos
Cromossomos , Replicação do DNA , Drosophila melanogaster/genética , Olho , Regulação da Expressão Gênica/fisiologia , Característica Quantitativa Herdável , Animais , Técnicas de Cultura , Feminino , Larva/genética , Masculino
8.
Tsitol Genet ; 33(5): 64-71, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10643046

RESUMO

The influence of hormones--adrenaline, noradrenaline, hydrocortisone on the electronegativity of cell nuclei (ENN) was shown by the method of intracellular microelectrophoresis. Changes in heterochromatin state were estimated on the basis of heterochromatin granules (chromocenters) quantity. Adrenaline and noradrenaline induced the decrease in ENN, the maximum effect was revealed with hormones concentration observed in human blood during physical training. The hormonal effect increased with gradual increase of the exposition time from 5 to 120 min. Hydrocortisone also decreased ENN. Adrenaline, and in some cases hydrocortisone, induced the significant increase of heterochromatin granule quantity. The correlation of this process with ENN decrease was shown only in the case of adrenaline. Obtained data are discussed in connection with regulation mechanisms of cell nucleus functional activity.


Assuntos
Núcleo Celular/efeitos dos fármacos , Cromatina/efeitos dos fármacos , Epinefrina/farmacologia , Hidrocortisona/farmacologia , Norepinefrina/farmacologia , Adolescente , Adulto , Idoso , Núcleo Celular/fisiologia , Células Cultivadas , Bochecha , Cromatina/fisiologia , Relação Dose-Resposta a Droga , Eletrofisiologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Humanos , Interfase/efeitos dos fármacos , Pessoa de Meia-Idade , Fatores de Tempo
9.
Bioelectromagnetics ; 19(7): 414-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9771584

RESUMO

Changes of electrokinetic properties of cell nuclei and the quantity of granules of heterochromatin located near the nuclear envelope in nuclei of human buccal epithelium cells were studied under the influence of electromagnetic fields in vitro. Irradiation of cells was realized by means of a semiconductor generator of millimeter radiation (wavelength 7.1 mm, frequency 42.2 GHz), the Yav-1 apparatus for extremely high frequency therapy. It was shown that irradiation of cells induced a decrease in electric charge of native human buccal epithelium cell nuclei and an increase in chromatin condensation in nuclei. The observed effects depend on irradiation dose and individual peculiarities of donors.


Assuntos
Núcleo Celular/efeitos da radiação , Heterocromatina/efeitos da radiação , Micro-Ondas , Mucosa Bucal/efeitos da radiação , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Mucosa Bucal/ultraestrutura , Semicondutores
10.
Genetika ; 33(6): 793-9, 1997 Jun.
Artigo em Russo | MEDLINE | ID: mdl-9289417

RESUMO

The degree of polyteny of giant chromosomes and electrokinetic properties of cell nuclei salivary glands of Drosophila melanogaster were studied in relation to genotype and rearing temperature. Inbred and selected Drosophila lines and interlinear F1 hybrids were used. The experiments were conducted in three temperature regimes: 25 (control), 18, and 28 degrees C. At low (18 degrees C) and high (28 degrees C) temperatures, the degree of polyteny and number of electronegative nuclei was respectively higher and lower than in the control. The correlation of these parameters with a number of adaptive traits was studied. The results suggest that chromosome polyteny and nuclear electrokinetic potential play a significant role in heterosis and adaptation of Drosophila melanogaster to adverse temperatures.


Assuntos
Adaptação Fisiológica/genética , Drosophila melanogaster/fisiologia , Animais , Núcleo Celular , Drosophila melanogaster/genética , Genótipo , Temperatura
11.
Mech Ageing Dev ; 99(3): 193-7, 1997 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-9483492

RESUMO

An original method of intracellular microelectrophoresis of cell nuclei has been developed and using this technique the dependence of the electrokinetic potential of cell nuclei on the human age is calculated. This new method, obtained for every age group, allows the calculation of electrokinetic potentials, the determination of human biological ages and changes in energies of an organism provoked by different causes, i.e. tiredness, medical drugs and narcotics consumption. Ionizing radiation, etc. can also be determined. This method is applied to many areas of medicine, sport and work practice.


Assuntos
Células Epiteliais/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Núcleo Celular , Criança , Pré-Escolar , Eletroforese/métodos , Humanos , Cinética , Pessoa de Meia-Idade
13.
Mech Ageing Dev ; 83(2): 87-90, 1995 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-8569288

RESUMO

An original method for the determination of cell membrane permeability has been developed. Human buccal epithelium cells were treated with Indigo Carmine and the percentage of stained cells was determined. Employing this method, the age-related differences in properties of plasma membrane in cells of human buccal epithelium were demonstrated. In the group of aged donors the average level of cell stainability was higher than in the group of younger donors. These results demonstrate a decrease in outer cell membrane integrity with age.


Assuntos
Envelhecimento/fisiologia , Permeabilidade da Membrana Celular/fisiologia , Mucosa Bucal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Celular/metabolismo , Epitélio/metabolismo , Escina/farmacocinética , Humanos , Pessoa de Meia-Idade , Mucosa Bucal/citologia
15.
Genetika ; 31(1): 24-9, 1995 Jan.
Artigo em Russo | MEDLINE | ID: mdl-7896126

RESUMO

Four classes of cell nuclei containing polytene chromosomes of different diameters were detected in the salivary glands of Drosophila at the stage of 0-hour prepupae. The diameter of chromosomes was shown to depend on the level of polyteny. In the selected highly inbred lines LA (low activity) and HA (high activity) and in their F1 hybrids LA x HA and HA x LA, the ratios of nuclei containing chromosomes with different levels of polyteny were analyzed. It was established that chromosomes of an inadaptive line LA have a decreased level of polyteny. The hybrids were superior to both parent lines in terms of the trait studied. Giant chromosomes of line and hybrid females had higher levels of polyteny than male chromosomes. It is shown that the level of polyteny of giant chromosomes in Drosophila lines and their hybrids is correlated with differences in traits with a high adaptive value, such as rate of development, fertility, heat resistance, competitiveness, etc.


Assuntos
Adaptação Fisiológica/genética , Cromossomos/ultraestrutura , Drosophila melanogaster/genética , Heterozigoto , Seleção Genética , Animais , Drosophila melanogaster/fisiologia , Feminino , Hibridização Genética , Masculino , Fatores Sexuais
16.
Genetika ; 27(9): 1512-8, 1991 Sep.
Artigo em Russo | MEDLINE | ID: mdl-1778459

RESUMO

Regression of 4 intermolt and induction of 14 early ecdysone puffs in two inbred stocks of Drosophila with high (HA) and low (LA) activity and hybrid F1 HA x LA were studied. Experiments were performed in vitro with ecdysone-containing media. Differences in developmental rate and fitness of stocks HA, LA and their hybrid were shown to correlate with the rate of change in polythene chromosomes puffing activity. Adaptive heterosis and ontogenetic homeostasis mechanisms are under discussion in connection with the results obtained.


Assuntos
Drosophila melanogaster/genética , Ecdisona/fisiologia , Vigor Híbrido/genética , Glândulas Salivares/fisiologia , Seleção Genética , Transcrição Gênica/genética , Adaptação Fisiológica/fisiologia , Animais , Homeostase/fisiologia , Análise de Regressão
17.
Genetika ; 26(5): 874-8, 1990 May.
Artigo em Russo | MEDLINE | ID: mdl-2118875

RESUMO

The dynamics of heat-shock puff activity and cell nuclei electrophoretic mobility in the larvae salivary glands of normal and temperature-sensitive mutant stocks of Drosophila melanogaster after heat shock (37 degrees C) were studied. The parallel changes of these characters and interlinear differences affected by ts mutation were found. Positive correlation between heat shock puff size and cell nuclei electrophoretic mobility was detected.


Assuntos
Cromossomos/ultraestrutura , Drosophila melanogaster/genética , Eletricidade , Proteínas de Choque Térmico/biossíntese , Glândulas Salivares/ultraestrutura , Animais , Núcleo Celular/fisiologia , Drosophila melanogaster/fisiologia , Proteínas de Choque Térmico/genética , Glândulas Salivares/fisiologia
18.
Genetika ; 26(5): 879-85, 1990 May.
Artigo em Russo | MEDLINE | ID: mdl-2118876

RESUMO

Spontaneous and high temperature-induced crossing over in regions b-cn and cn-vg of chromosome 2 was studied in Drosophila stocks and hybrids differing in fertility level and heat resistance. No essential distinction in recombination frequency was revealed in variants studied under the temperature 21-22 degrees C. The effect of temperature on 1- and 10-days imago during 4 or 7 h under 35 degrees C leads to increase in exchange frequency in the region b-cn. The hybrids show weaker reaction to this influence.


Assuntos
Drosophila melanogaster/genética , Temperatura Alta , Vigor Híbrido , Hibridização Genética , Recombinação Genética , Animais , Feminino , Masculino
20.
Genetika ; 26(1): 43-8, 1990 Jan.
Artigo em Russo | MEDLINE | ID: mdl-2111788

RESUMO

This study is aimed at elucidating the mechanisms of high heat resistance of heterosis hybrids. For this purpose, the dynamics of heat shock puffs of the high-inbred HA and BA lines as well as the HAxBA heterosis hybrids has been studied. Inadaptive properties of the HA line were observed to be expressed at the organism and cell levels, which is reflected by later induction of heat shock puffs. In the hybrids, these puffs occur considerably quicker, when heated, than with the high-inbred lines. Our conclusion is that the dynamics peculiarities of heat shock puffs reflect the differences in line and hybrid heat resistance. The higher heat resistance of the hybrid manifests itself in an earlier induction of heat shock puffs.


Assuntos
Cromossomos/ultraestrutura , Drosophila melanogaster/genética , Proteínas de Choque Térmico/genética , Animais , Cruzamentos Genéticos , Temperatura Alta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...