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1.
Genes Immun ; 16(4): 239-46, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25764117

RESUMO

Mendelian primary immunodeficiency diseases (MPIDs) are rare disorders affecting distinct constituents of the innate and adaptive immune system. Although they are genetically heterogeneous, a substantial group of MPIDs is due to mutations in genes affecting the nuclear factor-κB (NF-κB) transcription pathway, essential for cell proliferation and cell survival and involved in innate immunity and inflammation. Many of these genes encode for crucial regulatory components of the NF-κB pathway and their mutations are associated with immunological and developmental signs somehow overlapping in patients with MPIDs. At present, nine different MPIDs listed in the online mendelian inheritance in man (OMIM) are caused by mutations in at least nine different genes strictly involved in the NF-κB pathway that result in defects in immune responses. Here we report on the distinct function of each causative gene, on the impaired NF-κB step and more in general on the molecular mechanisms underlining the pathogenesis of the disease. Overall, the MPIDs affecting the NF-κB signalosome require a careful integrated diagnosis and appropriate genetic tests to be molecularly identified. Their discovery at an ever-increasing rate will help establish a common therapeutic strategy for a subclass of immunodeficient patients.


Assuntos
Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/metabolismo , NF-kappa B/metabolismo , Displasia Ectodérmica/genética , Displasia Ectodérmica/imunologia , Genes Recessivos , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Síndromes de Imunodeficiência/imunologia , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/imunologia , Mutação , NF-kappa B/genética , Doenças da Imunodeficiência Primária , Doenças Raras/genética , Doenças Raras/imunologia , Transdução de Sinais/genética
2.
Zygote ; 23(1): 11-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23673140

RESUMO

Several genetic and physiological factors increase the risk of DNA damage in mammalian oocytes. Two critical events are: (i) meiosis progression, from maturation to fertilization, due to extensive chromatin remodelling during genome decondensation; and (ii) aging, which is associated with a progressive oxidative stress. In this work, we studied the transcriptional patterns of three genes, RAD51, APEX-1 and MLH1, involved in DNA repair mechanisms. The analyses were performed by real-time quantitative PCR (RT-qPCR) in immature and in vitro matured oocytes collected from 17 ± 3-month-old heifers and 94 ± 20-month-old cows. Batches of 30-50 oocytes for each group (three replicates) were collected from ovarian follicles of slaughtered animals. The oocytes were freed from cumulus cells at the time of follicle removal, or after in vitro maturation (IVM) carried out in M199 supplemented with 10% fetal calf serum, 10 IU luteinising hormone (LH)/ml, 0.1 IU follicle-stimulating hormone (FSH)/ml and 1 µg 17ß-oestradiol/ml. Total RNA was extracted by Trizol method. The expression of bovine GAPDH gene was used as the internal standard, while primers for bovine RAD51, APEX-1 and MLH1 genes were designed from DNA sequences retrieved from GenBank. Results obtained indicate a clear up-regulation of RAD51, APEX-1 and MLH1 genes after IVM, ranging between two- and four-fold compared with germinal vesicle (GV) oocytes. However, only RAD51 showed a significant transcript increase between the immature oocytes collected from young or old individuals. This finding highlights RAD51 as a candidate gene marker for discriminating bovine immature oocytes in relation to the donor age.


Assuntos
Reparo do DNA/genética , Meiose , Oócitos/fisiologia , Fatores Etários , Animais , Bovinos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Feminino , Perfilação da Expressão Gênica , Técnicas de Maturação in Vitro de Oócitos , Proteínas Nucleares/genética , Rad51 Recombinase/genética
3.
J Biol Regul Homeost Agents ; 25(3): 469-75, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22023773

RESUMO

von Willebrand 's disease (vWD) is the commonest inherited bleeding disorder. Although in literature there are some cases reported of epidural analgesia for labor pain in pregnancies with Von Willebrand's disease, the technique is not free from risk of neurolocal complications. Authors reported a case of spontaneous labor in a pregnant woman with type II vWD, delivered under local analgesia administered through a continuous intravenous infusion of remifentanil integrated by boli. A 34-year-old woman at the 39th week of her second pregnancy was admitted for an active labor of a single fetus in cephalic presentation. The patient had been diagnosed with type II vWD by a hematologist during her first pregnancy. The patient coagulation panel was as follows: a reduction of VIIIth factor concentration (21 percent); a normal value of vWD functional assay; an increase of vWf:Ag (antigen) and a reduction of XIth factor. During labor she was put on remifentanil in PCA (patient controlled analgesia), administered with slow boli followed by continuous infusions at increasing doses. The woman delivered a female fetus weighing 3,550 g, in vertex presentation, in left anterior occipital position, with an A.P.G.A.R. of 8 at the first minute and 9 at the fifth minute. The total duration of labor was 3 hours and 10 minutes. The patient was satisfied with analgesia in labor. The bleeding during and after delivery was regular. In the authors ' opinion, it is important to know that an alternative to epidural analgesia can be used in order to avoid the risk of neurological complications in labor pain for patients with type II Von Willebrand's disease.


Assuntos
Analgesia Epidural , Anestésicos Intravenosos/administração & dosagem , Piperidinas/administração & dosagem , Complicações Hematológicas na Gravidez/sangue , Nascimento a Termo/sangue , Doença de von Willebrand Tipo 2/sangue , Adulto , Fator VIII/metabolismo , Fator XI/metabolismo , Feminino , Humanos , Dor/sangue , Dor/prevenção & controle , Gravidez/sangue , Remifentanil
4.
Hum Reprod ; 26(5): 1191-201, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21357606

RESUMO

BACKGROUND: The oocyte-to-embryo transition (OET) requires a co-ordinated transcriptional programme acting through evolutionarily conserved events, and transcription factors (TFs) are known to control these processes. Here, we focus on nuclear factor (NF)-κB, a TF involved in several cellular processes, studying NFκB-inhibitor (NFKBIA) mRNA and its protein product, IκBα, during OET. NFKBIA and IκBα are part of a regulatory loop, as IκBα is the major down-regulator of NF-κB activation while NFKBIA transcription is activated by NF-κB. METHODS AND RESULTS: We found a dynamic correlation between NFKBIA transcript, expression of IκBα-protein and activation of NF-κB/p65 in bovine oocyte and embryo. During the transition from immature to in vitro matured bovine oocyte, we observed a decrease in maternal NFKBIA mRNA and a parallel increase of the IκBα-protein (both P < 0.05). In the embryo, NFKBIA neo-synthesis is activated as a consequence of embryo genome activation (EGA), and IκBα decreases. NF-κB/p65-binding activity was detectable at low levels in immature oocyte, disappeared in dormant metaphase II oocyte and was strong in the embryo, during embryonic NFKBIA synthesis. The level of NF-κB/p65 DNA binding correlates with the timing of meiotic silencing during bovine oocyte maturation and embryonic transcription reprogramming. CONCLUSIONS: The IκBα/NF-κB circuit appears to be a tightly stage-controlled mechanism that could govern OET, being activated at EGA. Our findings represent the first characterization of NFKBIA and IκBα as maternal effectors in both the bovine oocyte and embryo. We suggest a role for NFKBIA as a marker of NF-κB/p65 activation in the human oocyte and early embryo.


Assuntos
Desenvolvimento Embrionário/fisiologia , Proteínas I-kappa B/fisiologia , NF-kappa B/metabolismo , Oócitos/crescimento & desenvolvimento , Fator de Transcrição RelA/metabolismo , Sequência de Aminoácidos , Animais , Bovinos , Desenvolvimento Embrionário/genética , Ativação Enzimática , Proteínas I-kappa B/análise , Proteínas I-kappa B/metabolismo , Dados de Sequência Molecular , Inibidor de NF-kappaB alfa , Oócitos/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Fator de Transcrição RelA/análise , Fator de Transcrição RelA/fisiologia
5.
Bioelectromagnetics ; 26(4): 258-65, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15832336

RESUMO

Human peripheral blood leukocytes from healthy volunteers have been employed to investigate the induction of genotoxic effects following 2 h exposure to 900 MHz radiofrequency radiation. The GSM signal has been studied at specific absorption rates (SAR) of 0.3 and 1 W/kg. The exposures were carried out in a waveguide system under strictly controlled conditions of both dosimetry and temperature. The same temperature conditions (37.0 +/- 0.1 degrees C) were realized in a second waveguide, employed to perform sham exposures. The induction of DNA damage was evaluated in leukocytes by applying the alkaline single cell gel electrophoresis (SCGE)/comet assay, while structural chromosome aberrations and sister chromatid exchanges were evaluated in lymphocytes stimulated with phytohemagglutinin. Alterations in kinetics of cell proliferation were determined by calculating the mitotic index. Positive controls were also provided by using methyl methanesulfonate (MMS) for comet assay and mitomycin-C (MMC), for chromosome aberration, or sister chromatid exchange tests. No statistically significant differences were detected in exposed samples in comparison with sham exposed ones for all the parameters investigated. On the contrary, the positive controls gave a statistically significant increase in DNA damage in all cases, as expected. Thus the results obtained in our experimental conditions do not support the hypothesis that 900 MHz radiofrequency field exposure induces DNA damage in human peripheral blood leukocytes in this range of SAR.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos/efeitos da radiação , Dano ao DNA , DNA/efeitos da radiação , Leucócitos/patologia , Leucócitos/efeitos da radiação , Micro-Ondas/efeitos adversos , Telefone Celular , Células Cultivadas , Cromossomos Humanos/genética , DNA/genética , Relação Dose-Resposta à Radiação , Humanos , Doses de Radiação
6.
J Comp Pathol ; 131(2-3): 233-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15276863

RESUMO

Chromosomal aberrations were investigated in 56 cattle with chronic enzootic haematuria (CEH) raised on pastures giving access to bracken fern. Of these animals, 27 were slaughtered and showed neoplastic lesions of the urinary bladder. Tumour tissue from 11 of the 27 cattle contained bovine papillomavirus type 2 (BPV-2) DNA. Increased numbers of chromosomal aberrations were seen in all animals with CEH, as compared with 30 control cattle that had had no access to bracken fern. The highest clastogenic effect was observed in cattle with urinary bladder cancer and evidence of BPV-2 DNA, suggesting that BPV-2 and bracken fern act synergistically in the production of chromosomal instability. In 19 of 20 animals with CEH, two bracken fern toxic compounds (quercitin and ptaquiloside) were demonstrated in urine, serum and milk.


Assuntos
Doenças dos Bovinos/genética , Aberrações Cromossômicas/induzido quimicamente , Hematúria/veterinária , Intoxicação por Plantas/veterinária , Pteridium/efeitos adversos , Animais , Papillomavirus Bovino 1 , Bovinos , Doenças dos Bovinos/etiologia , Hematúria/etiologia , Hematúria/genética , Indanos/análise , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/veterinária , Intoxicação por Plantas/complicações , Reação em Cadeia da Polimerase , Quercetina/análise , Sesquiterpenos/análise , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/veterinária , Neoplasias da Bexiga Urinária/virologia
7.
Mutat Res ; 557(1): 19-27, 2004 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-14706515

RESUMO

Ochratoxin A (OTA) and zearalenone (ZEA), two naturally occurring contaminants of animal feed, have been implicated in several mycotoxicoses in farm livestock but there is little information on their genotoxicity and toxicity in these species. Therefore, we investigated on the cytogenetic and cytotoxic effects of both OTA and ZEA in in vitro cultures of bovine lymphocytes. We determined chromosome aberrations (CAs) and sister chromatid exchanges (SCEs) as well as the mitotic index (MI) and cell viability following OTA and ZEA treatment. This report is the first to provide evidence of a statistically significant increase of structural CAs and of SCEs/cell associated with a reduction of the MI in all OTA- and ZEA-treated bovine lymphocyte cultures and a clear reproducible reducing effect of OTA on cell viability mediated by enhanced apoptosis. OTA-induced programmed cell death was not limited to bovine lymphocytes, as comparable data were demonstrated in the human leukemic T-cell line Jurkat.


Assuntos
Apoptose/efeitos dos fármacos , Aberrações Cromossômicas/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Ocratoxinas/toxicidade , Troca de Cromátide Irmã/efeitos dos fármacos , Zearalenona/toxicidade , Animais , Bovinos , Relação Dose-Resposta a Droga , Linfócitos/ultraestrutura
8.
Health Phys ; 76(3): 244-50, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10025649

RESUMO

In the present study micronucleus induction and cell proliferation in human peripheral blood lymphocytes cultured in vitro and exposed to 50 Hz sinusoidal magnetic fields for 72 h at different intensities (1.0, 0.75, 0.5, 0.25, and 0.05 mT rms) were investigated. The results obtained from 42 healthy donors aged between 26 and 54 y indicate that, for the field intensities tested, no genotoxic effects were found, as assessed by the cytokinesis-block micronucleus assay. On the contrary, cell proliferation, evaluated by the cytokinesis-block proliferation index, was slightly affected by the field at the intensities tested.


Assuntos
Linfócitos/efeitos da radiação , Magnetismo , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Divisão Celular/efeitos da radiação , Células Cultivadas , Humanos , Linfócitos/ultraestrutura , Micronúcleos com Defeito Cromossômico/ultraestrutura , Testes para Micronúcleos
9.
Mutat Res ; 403(1-2): 13-20, 1998 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-9726001

RESUMO

The genotoxic activity of the pesticides gliphosate, vinclozolin and DPX-E9636 was studied in in vitro cultures of bovine lymphocytes, using chromosome aberration (CA) and sister chromatid exchange (SCE) frequencies as genetic end-points and a variation of glucose 6-phosphate dehydrogenase (G6PD) enzyme activity as a marker of changes in the normal cell redox state. Results indicated a statistically significant increase of structural aberrations, sister chromatid exchanges and G6PD activity, suggesting that the pesticides tested induce either oxidative stress or a mutagenic effect in this species. The evaluation of both mitotic index and cell viability, after pesticide exposure, demonstrates a high cytotoxic effect which is always associated with the observed genotoxic effect.


Assuntos
Linfócitos/efeitos dos fármacos , Mutagênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/toxicidade , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Aberrações Cromossômicas , Glucosefosfato Desidrogenase/metabolismo , Glicina/análogos & derivados , Glicina/toxicidade , Técnicas In Vitro , Linfócitos/citologia , Linfócitos/metabolismo , Índice Mitótico , Testes de Mutagenicidade , Oxazóis/toxicidade , Oxirredução , Troca de Cromátide Irmã/efeitos dos fármacos , Ureia/análogos & derivados , Ureia/toxicidade , Glifosato
10.
Environ Mol Mutagen ; 32(1): 39-46, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9707097

RESUMO

We analyzed chromosome aberrations (CAs), sister chromatid exchanges (SCEs), mitotic index (MI), and glucose 6-phosphate dehydrogenase (G6PD) enzyme activity in human peripheral lymphocytes from three healthy donors exposed in vitro to different concentrations of gliphosate, vinclozolin, atrazine, and DPX-E9636. The pesticides gliphosate, vinclozolin, and atrazine have been studied in a broad range of genetic tests with predominantly conflicting or negative results, whereas little is known about the genotoxicity of DPX-E9636. In our experimental conditions, each chemical compound tested produced a dose-related increase in the percent of aberrant cells and an increase of SCE/cell. Furthermore, at the highest concentrations of vinclozolin, atrazine, and DPX-E9636, we observed a significant reduction of the mitotic index. The increase of G6PD activity in exposed lymphocyte cultures strongly indicated an induction of a pro-oxidant state of the cells as an initial response to pesticide exposure.


Assuntos
Atrazina/toxicidade , Aberrações Cromossômicas , Linfócitos/efeitos dos fármacos , Oxazóis/toxicidade , Estresse Oxidativo , Praguicidas/toxicidade , Ureia/análogos & derivados , Células Cultivadas , Glucosefosfato Desidrogenase/metabolismo , Humanos , Linfócitos/enzimologia , Mutagênicos/toxicidade , Oxidantes , Troca de Cromátide Irmã , Ureia/toxicidade
11.
Hereditas ; 127(3): 231-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9474905

RESUMO

The spontaneous level of sister chromatid exchanges (SCEs) in the sheep, estimated by exposing peripheral blood lymphocytes in 0.1 microgram/ml of 5'-bromodeoxyuridine (BrdU), was 4.08 +/- 2.47 SCE/cell, 2.04 SCE/cell cycle, 0.038 SCE/chromosome. The dose-response relationships, observed by exposing the cells to 0.1, 0.25, 0.5, 1.0, 2.5, and 5.0 micrograms/ml of BrdU, rose rapidly from 0.1 to 0.25 microgram/ml, and less rapidly at higher concentrations, thus reaching a saturation level. The analysis of variance, performed on the square root transformed data at 0.1 and 5 micrograms/ml of BrdU, indicated significant differences (P < 0.001) among the four donors tested. The distribution of the SCE/cell frequencies in the cell population of the four donors followed the Poisson 'mixture' probability function, thus confirming previous findings. The spontaneous rate of SCE/cell of sheep is compared with those previously reported for cattle, goat and river buffalo. The theoretical and practical implications of the spontaneous sister chromatid exchanges are discussed in relation to their possible use in animal production for (a) better genetic evaluation of the breeding animals under selection, (b) more precise monitoring of the genotoxic effects of environmental pollutants.


Assuntos
Búfalos/genética , Bovinos/genética , Cromossomos/genética , Cabras/genética , Ovinos/genética , Troca de Cromátide Irmã , Animais , Feminino , Masculino , Mitose
12.
Mutat Res ; 357(1-2): 183-90, 1996 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-8876693

RESUMO

Peripheral blood lymphocytes from 15 subjects affected by Turner's syndrome (TS) and aged between 2 and 24 years (mean age 10.40 +/- 6.25) were tested to evaluate the spontaneous and Mitomycin-C-induced (MMC) micronucleus (MN) frequency. A group of 15 healthy subjects, in the same range of age (mean age 14.67 +/- 8.30), was also tested as control. As expected, statistically significant differences between spontaneous and MMC-induced MN were found either in TS and in healthy subjects. Unexpectedly, when the two groups of donors were compared, TS subjects showed a lower spontaneous and MMC-induced MN frequency, in comparison with healthy subjects. Cell proliferation kinetic and cytotoxicity were also measured applying the cytokinesis-block proliferation index (CBPI): the results show that MMC, at the employed concentration, does not induce cell cycle delay both in healthy and in TS donors. Whereas, when CBPI from TS and healthy donors were compared, a faster proliferation was found in TS patients in both untreated and MMC-treated cultures.


Assuntos
Síndrome de Turner/genética , Adolescente , Adulto , Envelhecimento , Divisão Celular/efeitos dos fármacos , Criança , Pré-Escolar , Aberrações Cromossômicas , Feminino , Humanos , Testes para Micronúcleos , Mitomicina/farmacologia , Mutagênicos/farmacologia , Síndrome de Turner/patologia , Síndrome de Turner/fisiopatologia
13.
Hereditas ; 124(2): 137-43, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8782434

RESUMO

The spontaneous level of sister chromatid exchange (SCEs) in the goat, estimated by exposing peripheral blood lymphocytes to 0.1 microgram/ml of 5-bromodeoxyuridine (BrdU), was 3.28 +/- 1.71 SCE/cell, 1.64 SCE/cell generation and 0.027 SCE/chromosome. The dose-response curve of SCE/cell, observed by exposing the cells to 0.1, 0.25, 0.5, 1.0, 2.5, and 5.0 micrograms/ml of BrdU, rose rapidly from 0.1 to 0.5 microgram/ml, remained fairly stable from 0.5 to 1.0 microgram/ml and rose less rapidly from 1.0 to 5.0 micrograms/ml of BrdU. The frequency distribution of sister chromatid exchanges/cell and that of chromosomes showing various number of exchanges followed the Poisson probability at all BrdU levels; only at 5.0 micrograms/ml of BrdU was the fit found on the border of the 5% probability level. The usefulness of determining the spontaneous level of SCE/cell in domestic animals is discussed in relation to its possible application for a more precise evaluation of the genotoxic effects of environmental pollutants.


Assuntos
Bromodesoxiuridina , Cromossomos , Cabras/genética , Mitose/efeitos dos fármacos , Troca de Cromátide Irmã , Animais , Relação Dose-Resposta a Droga
14.
Mutat Res ; 306(2): 129-33, 1994 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7512211

RESUMO

We exposed human peripheral blood lymphocyte cultures to 50 Hz pulsed magnetic fields (PMFs) in order to evaluate a possible genotoxic effect of such non-ionizing radiation. The genotoxic effect was evaluated in terms of both micronucleus (MN) induction and classical chromosomal aberrations (CA); the mitotic index (MI) was also calculated. Khalil and Qassem (1991) found chromosomal and chromatid breaks and mitotic delay in human lymphocytes exposed for 24, 48 and 72 h to a field with characteristics similar to those used in our laboratory. These data are in contrast with our results previously reported in terms of MN induction using the cytokinesis block method (Scarfi et al., 1991). In this study lymphocytes from five healthy human donors were examined with the above mentioned tests. No genotoxic effects and increased MI were found in exposed samples compared to the control ones, in agreement with our previous results.


Assuntos
Aberrações Cromossômicas , Magnetismo , Testes para Micronúcleos , Células Cultivadas , Humanos , Linfócitos/ultraestrutura , Índice Mitótico
15.
Cytogenet Cell Genet ; 67(2): 75-80, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8039426

RESUMO

High resolution RBA-banding patterns of Dama dama prometaphase chromosomes and their ideograms are presented as models for the definition of the standard RBA-banded karyotype of the species. The haploid set of RBA-banded prometaphase chromosomes, including the X and Y gonosomes, has revealed 527 bands, of which 191 are R-positive, 254 are R-negative and 82 are intermediate.


Assuntos
Cervos/genética , Cariotipagem/veterinária , Animais , Tipagem e Reações Cruzadas Sanguíneas/veterinária , Bandeamento Cromossômico/veterinária , Feminino , Haploidia , Masculino
16.
Mutat Res ; 289(2): 291-5, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7690898

RESUMO

The present study was carried out in order to set up a standardized quantitative assay for spontaneous micronuclei in bovine lymphocytes. For this purpose the cytokinesis-block micronucleus (MN) method, originally proposed by Fenech and Morley (1985) for human lymphocytes, was applied to peripheral blood lymphocytes of 20 healthy cows of Italian Friesian breed. The results demonstrate that the optimal concentration of cytochalasin B to obtain the highest frequency of binucleated cells (mean = 400.26 +/- 23.76/1000 cells scored) was 6 micrograms/ml. The baseline frequency of spontaneous MN formation in 500 binucleated cells was 12.3 +/- 4.1, i.e., 3 times higher than that reported in human lymphocytes (Fenech and Morley, 1985; Scarfi et al., 1991). The possible reason(s) for this difference (sensitivity to cytochalasin B, chromosome number, environmental genotoxic pollutants) is discussed.


Assuntos
Divisão Celular/efeitos dos fármacos , Citocalasina B/farmacologia , Testes para Micronúcleos/métodos , Animais , Bovinos , Feminino , Contagem de Leucócitos , Linfócitos
17.
Radiat Res ; 135(1): 64-8, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8327662

RESUMO

Electromagnetic fields produce a variety of effects in several biological systems, including human peripheral blood lymphocytes. A great concern exists regarding possible carcinogenic effects in subjects exposed environmentally to such fields in the vicinity of power lines and electric domestic appliances. Using human lymphocytes from 33 healthy donors and a sensitive cytogenetic method, the cytokinesis-block micronucleus assay, we have demonstrated that the exposure to 50-Hz AC sinusoidal electric fields over a wide range of intensities (0.5-10 kV/m in air) does not increase the spontaneous frequency of micronuclei. Moreover, these fields did not affect the mitomycin-C-induced micronucleus formation, suggesting that they did not exert any synergistic or antagonistic effect.


Assuntos
Campos Eletromagnéticos , Linfócitos/efeitos da radiação , Mutação , Adulto , Idoso , Células Cultivadas , Humanos , Linfócitos/efeitos dos fármacos , Testes para Micronúcleos , Pessoa de Meia-Idade , Mitomicina/toxicidade
19.
Mutat Res ; 237(5-6): 247-52, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2150431

RESUMO

Peripheral blood lymphocytes from 7 patients with Down's syndrome (DS; trisomy 21) and 14 healthy age-matched controls were studied for the induction of micronuclei (MN) by the cytokinesis-block method. The spontaneous incidence of MN in lymphocytes from DS subjects was lower than that of control cultures. When lymphocytes were treated with mitomycin C (MMC) at the beginning of the culture period, an increase in MN formation was found in cells from both DS and control subjects. In DS subjects this increase was much more marked than in control donors. This effect had to be ascribed to cells from older DS subjects (37-55 years old), which showed an MMC-induced MN formation that was markedly and significantly higher than that observed in cells from younger (9-16 years old) DS subjects. These data indicate that age has to be considered a major variable when studies on the genetic instability of DS subjects are performed.


Assuntos
Envelhecimento/genética , Síndrome de Down/fisiopatologia , Linfócitos/citologia , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Mitomicinas/farmacologia , Adolescente , Adulto , Criança , Síndrome de Down/genética , Feminino , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/patologia , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Mitomicina , Valores de Referência
20.
J Hered ; 78(4): 225-30, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3624843

RESUMO

R-banded prometaphase karyotypes of the goat are presented using both fluorescent and light staining techniques. A model for the standardization of the R-banded prometaphase goat karyotype is suggested.


Assuntos
Cromossomos/ultraestrutura , Cabras/genética , Animais , Células Cultivadas , Bandeamento Cromossômico , Replicação do DNA , Feminino , Cariotipagem , Masculino , Metáfase
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