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1.
Tsitologiia ; 58(8): 646-54, 2016.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-30183213

RESUMO

The effect of the haloperidol (HP), a dopamine D2-receptor antagonist on the function of ionic channels of the electrically excitable plasma membrane and on the cytoskeleton of Chara corallina cells was investigated. Haloperidol was shown to block plasmalemmal Ca2+ channels. Apart from Ca2+ current reduction, the presence of HP slowed the kinetics of both activation and inactivation of ionic channels. The influence of haloperidol on the membrane structure was reversible. After removal of the neuromodulator, both the amplitude and the kinetics of the current development were seen to be completely restored. HP had no effect on Ca2+-activated chloride channels. Haloperidol inhibited cytoplasmic motion related to microfilamentary complex. Once haloperidol was removed from cell washing solution, cytoplasmic motion was restored. These results let us to assume that in the presence of HP the concentration of free Ca2+ in cytoplasm increases. Also it can be assumed that plasmalemmal Ca2+-channels of Ch. corallina cells contain binding sites similar to dopamine receptors and their antagonists.


Assuntos
Antagonistas de Dopamina/farmacologia , Haloperidol/farmacologia , Transporte de Íons/efeitos dos fármacos , Cálcio , Membrana Celular , Chara , Citoplasma
2.
Cryo Letters ; 26(5): 279-88, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-19827243

RESUMO

The experimental data presented in the work testify to the cytostatic activity of 1-10 kD polypeptide fractions from brains of the hibernating ground squirrel and the Yakut horse towards Ehrlich ascitic carcinoma (EAC) cells. The experiments on the investigation of the inhibiting influence of 1-10 kD fractions from tissues of the hibernating and cold-adapted animals on protein-synthesizing system of EAC cells allow us to conclude that the cytostatic effect of the fractions is effected at the genetic level in the tumor cells.


Assuntos
Encéfalo/metabolismo , Carcinoma de Ehrlich/metabolismo , Carcinoma de Ehrlich/patologia , Proliferação de Células/efeitos dos fármacos , Hibernação/fisiologia , Peptídeos/farmacologia , Proteínas/metabolismo , Adaptação Fisiológica/fisiologia , Animais , Temperatura Baixa , DNA/metabolismo , Cavalos , Peptídeos/metabolismo , Subunidades Proteicas/metabolismo , Subunidades Proteicas/farmacologia , RNA/metabolismo , Sciuridae
3.
Cryo Letters ; 24(2): 67-76, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12819827

RESUMO

The effect of cryopreservation on human spermatozoa has been investigated during the past few decades. The majority of current cryopreservation protocols are carried-out using low cooling rates. However, theoretical calculations have shown that for human spermatozoa an optimal cooling rate is about 7,000 C/min. In our work we have studied the effect of cryopreservation with high cooling rates, variation of osmolarity of the cryoprotectant medium and the glycerol content. The results of experiments have demonstrated that within the range of high cooling rates, after thawing the dependency of sperm survival on the cooling rate has a maximum recovery at 2,500-3,300 C/min in moderately hyperosmolar medium, containing 4-5% glycerol. When decreasing the cooling rate down to 1,750-2,500 C/min there was a statistically significant reduction in sperm motility. Using the cooling rate of 8,000-11,000 C /min only a small percentage of spermatozoa retained their motility.


Assuntos
Criopreservação/métodos , Preservação do Sêmen/métodos , Espermatozoides/citologia , Sobrevivência Celular , Crioprotetores/farmacologia , Glicerol/farmacologia , Humanos , Masculino , Suspensões/farmacologia , Temperatura , Tempo
4.
Cryo Letters ; 24(1): 27-32, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12644850

RESUMO

The effects of slow freezing-rapid thawing on viability and chromosomal complement of eight-cell early and eight-cell compacted mouse embryos were investigated. The abnormalities connected with damage to the mitotic apparatus, and with chromosome damage were investigated in cryopreserved embryos by cytological analysis. The embryos were preserved using 1M glycerol as cryoprotectant and a slow cooling regime to -30 degrees C before transfer to liquid nitrogen. The proportion of mitotic abnormalities in compacted embryos was significantly higher (13.1%) than in early embryos (5.9%) and unfrozen control embryos (3.9%) in these studies performed after thawing. This was reflected after cryopreservation by a reduced viability of the embryos as judged by culture to the hatching blastocyst stage--compacted 8-cell embryos (71.8+/-4.7%) versus controls (78.4+/-5.9%) and cryopreserved early-stage 8-cell embryos (86.1+/-4.0%)--p<0.05 in each case. However, aneuploidy rates were low in all groups in both fresh and cryopreserved embryos (around 3%).


Assuntos
Cromossomos/ultraestrutura , Criopreservação , Embrião de Mamíferos/ultraestrutura , Mitose , Aneuploidia , Animais , Camundongos
5.
Cryobiology ; 42(3): 218-21, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11578121

RESUMO

Investigations were carried out on the respiratory function of isolated rat hepatocytes after cold storage alone for periods up to 48 h in either sucrose-based solution (SBS) or University of Wisconsin (UW) solution and after subsequent normothermic preincubation. In both SBS and UW, cold storage for 24 h depressed respiratory function (to 21 +/- 3 and 23 +/- 3 nmol O(2)/min/10(6) cells, respectively) compared to control cell values (31 +/- 3 and 33 +/- 5 nmol O(2)/min/10(6) cells; P < 0.01 in each case). However, normothermic preincubation for 60 min returned respiratory activity to control values (for SBS and UW storage: 41 +/- 6 and 40 +/- 5 nmol O(2)/min/10(6) cells; for control cells: 43 +/- 5 and 46 +/- 6 nmol O(2)/min/10(6) cells). Storage for 48 h in both SBS and UW allowed further depression of respiratory activity, with no recovery after preincubation. Stimulation of respiration by succinate in hepatocytes stored for longer periods was suggestive of increased membrane permeability. Both SBS and UW are effective storage solutions for isolated hepatocytes for up to 24 h as judged by aerobic metabolism, but significant damage was expressed in both solutions when preservation was extended.


Assuntos
Criopreservação/métodos , Hepatócitos/metabolismo , Soluções para Preservação de Órgãos , Adenosina , Alopurinol , Animais , Permeabilidade da Membrana Celular , Respiração Celular , Crioprotetores , Glutationa , Técnicas In Vitro , Insulina , Cinética , Rafinose , Ratos , Sacarose
6.
Cryo Letters ; 22(4): 235-40, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11788864

RESUMO

The work describes the data on the selection of optimal hypothermic storage for progressively moving fraction of human spermatozoa isolated from ejaculate. Results were analysed by assessing sperm motility, oocyte fertilization rate, and embryonic development after re-insemination of unfertilized oocytes by spermatozoa stored under hypothermic conditions.


Assuntos
Temperatura Baixa , Fertilização in vitro , Preservação do Sêmen , Transferência Embrionária , Feminino , Fertilização , Humanos , Masculino , Retratamento , Motilidade dos Espermatozoides
7.
Cryobiology ; 41(4): 315-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11222028

RESUMO

A sucrose-based solution has been compared with other preservation solutions (University of Wisconsin (UW) solution and Marshall's citrate solution, with Dulbecco's medium as control) during hypothermic preservation of isolated rat hepatocytes for up to 72 h. Studies on the stability of liver cells at low temperature by exclusion of trypan blue dye and morphological appearance were conducted. During storage beyond 24 h, there was a clear difference between cells stored in Dulbecco's medium and Marshall's citrate and those stored in sucrose-based solution and UW solution, with the former storage groups showing many cells developing large membrane "blebs" and the latter storage groups maintaining a more typical morphology and developing only small membrane protrusions. Dye exclusion was higher in sucrose-based solution (48 h, 75 +/- 7%; 72 h, 65 +/- 6%) and UW solution (48 h, 72 +/- 5%; 72 h, 63 +/- 4%) than in Marshall's citrate (48 h, 31 +/- 5%; 72 h, 10 +/- 1%) and Dulbecco's medium (48 h, 8 +/- 2%; 72 h, 5 +/- 1%). These data suggest that sucrose-based solution should be investigated further as a less complex alternative solution for storage of isolated hepatocytes.


Assuntos
Hepatócitos , Soluções para Preservação de Órgãos , Preservação Biológica/métodos , Adenosina , Alopurinol , Animais , Temperatura Baixa , Corantes , Glutationa , Hepatócitos/citologia , Soluções Hipertônicas , Técnicas In Vitro , Insulina , Rafinose , Ratos , Sacarose , Azul Tripano
9.
Cryobiology ; 37(2): 103-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9769160

RESUMO

Increasing the cell concentration during the cryopreservation of red blood cells (RBC) increased hemolysis. Similarly, increasing the cell concentration during the cryopreservation of hepatocytes reduced both the viability of the cells as assessed by trypan blue exclusion and the metabolic activity of the trypan blue-excluding cells. In both cell types, significant damage appeared at cell concentration levels exceeding 60%. With tightly packed RBC, hemolysis reached 63%, while for hepatocytes after thawing and dilution, trypan blue viability was reduced to 41% of that of the cells initially isolated. The viability of cryopreserved hepatocytes, estimated by trypan blue exclusion, was considerably reduced following incubation for 1 h at 37 degrees C and the extent of this reduction was also a function of cell concentration during freezing and thawing. The trypan blue viability of hepatocytes that were tightly packed during cryopreservation and then incubated at a concentration of 5 x 10(6) viable cells/ml fell dramatically to only 12.5%. The protein-synthesizing activity and the membrane transport activity of these cells, expressed in terms of cells that excluded trypan blue immediately following thawing and removal of the cryoprotectant, were reduced to 38.7 and 33.5%, respectively, of the activity in cells that were packed at 10% cell concentration. The fall in metabolic activity may have been due to complete loss of activity in some of the cells or reduced activity in most or all of the cells or any combination of these factors. It is concluded that there may be many mechanisms involved, but the most important factor is probably stresses produced by unphysiological cell-cell contacts occurring during the freeze-thaw cycle.


Assuntos
Preservação de Sangue , Criopreservação , Eritrócitos , Fígado , Animais , Contagem de Células , Sobrevivência Celular , Humanos , Ratos
10.
Cryobiology ; 34(2): 150-6, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9130386

RESUMO

In an attempt to quantitatively evaluate the destructive effects of free radicals on metabolism, freshly prepared and cryopreserved isolated rat hepatocytes were exposed to and incubated with Fe2+ compounds, reputedly inducing oxygen-derived free radicals (OFR) capable of attacking the lipid structures of cellular membranes. Malondialdehyde (MDA) formation was interpreted as an expression of free radical interaction with polyunsaturated lipids, and in vitro incubations were carried out during the period of constant MDA formation. Protein synthesizing activity was evaluated by incubating control hepatocytes and cells previously exposed to 100 microM of Fe2+, to 100 microM of Fe2+, and 100 microM of desferrioxamine and to 100 microM of desferrioxamine alone with 0.1 microCi of L-[U-14C]isoleucine and in the presence of these compounds. Membrane transport activity was similarly evaluated by following the cellular uptake of alpha-amino-[1-14C]isobutyric acid. Protein-synthesizing activity of freshly prepared and cryopreserved hepatocytes was not affected by Fe2+ treatment, nor by the additions of the iron chelator desferrioxamine. Amino acid transport, however, was inhibited by 100 microM of Fe2+, but was effectively neutralized by the simultaneous addition of 100 microM of desferrioxamine. Cryopreserved hepatocytes equally presented a significantly inhibited amino acid transport activity over the incubation period. The results suggest that the metabolic depression measured in thawed hepatocytes does not result to any large extent from iron-catalysed OFR effects. When OFR production was deliberately induced, the most significant early change was seen in transmembrane amino acid uptake in both fresh and cryopreserved cells.


Assuntos
Criopreservação , Ferro/metabolismo , Fígado/citologia , Fígado/metabolismo , Estresse Oxidativo , Ácidos Aminoisobutíricos/metabolismo , Animais , Radicais Livres/metabolismo , Técnicas In Vitro , Ferro/farmacologia , Isoleucina/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Malondialdeído/metabolismo , Lipídeos de Membrana/metabolismo , Ratos , Ratos Wistar
11.
Environ Health Perspect ; 105 Suppl 6: 1445-9, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9467060

RESUMO

We present a pilot study of individuals (liquidators) who were engaged in clean-up operations after the disaster at the nuclear power plant at Chernobyl in Ukraine. In the 10 years since the disaster, adverse health effects among exposed individuals have not been clearly defined. There is widespread fear of damage to the reproductive system, with implications for fertility problems and adverse effects on offspring. Bearing this in mind, methods to evaluate the potential for production of fertile semen have been applied using quantitative ultramorphological (QUM) analysis. QUM analysis examines the organization and integrity of sperm organelles by electron microscopy, using both transmission electron microscopy and scanning electron microscopy. Significant differences were observed between clean-up workers and controls of similar age regarding certain ultramorphological parameters of the sperm head. The results of this pilot study suggest that QUM analysis of human sperm is a feasible approach for evaluating the fertility potential of individuals who were exposed to ionizing radiation from the Chernobyl nuclear power plant accident.


Assuntos
Exposição Ocupacional , Monitoramento de Radiação , Liberação Nociva de Radioativos , Espermatozoides/efeitos da radiação , Adulto , Humanos , Masculino , Sêmen/efeitos da radiação , Espermatozoides/ultraestrutura , Ucrânia
12.
Cryobiology ; 29(6): 679-84, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1282449

RESUMO

Synthesis of proteins and RNA has been studied by means of labeled precursors of 14C-labeled amino acids and [14C]orotic acid in liver cells of hibernating, arousing, and active ground squirrels (Citellus undulatus). The investigations indicate that cycloheximide (CHI)-inhibited protein synthesis in liver cells of hibernating ground squirrels may occur on preexisting polyribosomes. A low level of protein synthesis in this state results not only from the Arrhenius dependence, but also from the dissociation of polyribosomes into monosomes. During arousal there is an intensive assembly of polyribosomes. This occurs even with the inhibition of RNA synthesis by actinomycin D, testifying to the presence of a pool of iRNA in liver cells, which is necessary to activate translation. The intensity of protein synthesis in arousal is also influenced by the activation of transcription.


Assuntos
Hibernação/fisiologia , Biossíntese de Proteínas , Sciuridae/metabolismo , Animais , Nível de Alerta/fisiologia , Cicloeximida/farmacologia , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Técnicas In Vitro , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/ultraestrutura , Microscopia Eletrônica , RNA/biossíntese , Ribossomos/metabolismo
13.
Akush Ginekol (Mosk) ; (7): 39-41, 1989 Jul.
Artigo em Russo | MEDLINE | ID: mdl-2802066

RESUMO

Desirability of performing comprehensive clinical and immunological investigations of childless spouses was established. Treatment techniques such as insemination with husband's or, if necessary, donor's sperm were used in combination with specific desensitization therapy.


Assuntos
Reações Antígeno-Anticorpo , Muco do Colo Uterino/imunologia , Infertilidade Feminina/diagnóstico , Espermatozoides/imunologia , Dessensibilização Imunológica , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Inseminação Artificial , Masculino
14.
Int J Gynaecol Obstet ; 22(6): 479-82, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6152236

RESUMO

The principles on which the organization of Obstetric Services in the USSR is based are presented. The main types and functions of curative and preventive establishments which are related to the system of maternity and child protection and deliver obstetric care in the country are listed. The organizational structure of obstetric services, system of advanced training of doctors, the administrative machinery which directs the obstetric services, the development of scientific research in this field and feeding of results into practice are discussed.


Assuntos
Atenção à Saúde , Obstetrícia , Feminino , Humanos , Gravidez , U.R.S.S.
15.
J Reprod Immunol ; 2(5): 281-91, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7007636

RESUMO

Using immunofluorescence tests, antibodies reacting with pig zone pellucida could be detected in 31% of 103 sera from patients in different clinically defined categories, mainly fertile males and females and patients from couples with unexplained infertility. The antibodies could in all cases be absorbed by means of pig erythrocytes - in most sera with all erythrocyte suspensions tested, but in some cases only with erythrocytes from certain animals - indicating that antibodies both to generally occurring pig antigens and alloantigens may be present in human sera. Staining of pig zonae was recorded equally frequently with unabsorbed sera from infertile and fertile males and females, respectively, but titres of 1:16 or more occurred more frequently among infertile than among fertile female (P = 0.053).


Assuntos
Anticorpos , Imunofluorescência , Óvulo/imunologia , Zona Pelúcida/imunologia , Sistema ABO de Grupos Sanguíneos , Absorção , Animais , Especificidade de Anticorpos , Feminino , Fertilidade , Testes de Hemaglutinação , Humanos , Imunoglobulina G , Infertilidade/imunologia , Masculino , Coelhos , Especificidade da Espécie , Suínos
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