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2.
J Assist Reprod Genet ; 39(8): 1693-1712, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35870095

RESUMO

Since 2007, the Oncofertility Consortium Annual Conference has brought together a diverse network of individuals from a wide range of backgrounds and professional levels to disseminate emerging basic and clinical research findings in fertility preservation. This network also developed enduring educational materials to accelerate the pace and quality of field-wide scientific communication. Between 2007 and 2019, the Oncofertility Consortium Annual Conference was held as an in-person event in Chicago, IL. The conference attracted approximately 250 attendees each year representing 20 countries around the world. In 2020, however, the COVID-19 pandemic disrupted this paradigm and precluded an in-person meeting. Nevertheless, there remained an undeniable demand for the oncofertility community to convene. To maintain the momentum of the field, the Oncofertility Consortium hosted a day-long virtual meeting on March 5, 2021, with the theme of "Oncofertility Around the Globe" to highlight the diversity of clinical care and translational research that is ongoing around the world in this discipline. This virtual meeting was hosted using the vFairs ® conference platform and allowed over 700 people to participate, many of whom were first-time conference attendees. The agenda featured concurrent sessions from presenters in six continents which provided attendees a complete overview of the field and furthered our mission to create a global community of oncofertility practice. This paper provides a synopsis of talks delivered at this event and highlights the new advances and frontiers in the fields of oncofertility and fertility preservation around the globe from clinical practice and patient-centered efforts to translational research.


Assuntos
COVID-19 , Preservação da Fertilidade , Neoplasias , COVID-19/epidemiologia , Humanos , Pandemias
3.
J Assist Reprod Genet ; 37(7): 1567-1577, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32594284

RESUMO

PURPOSE: The state of limited resource settings that Coronavirus (COVID-19) pandemic has created globally should be taken seriously into account especially in healthcare sector. In oncofertility, patients should receive their fertility preservation treatments urgently even in limited resource settings before initiation of anticancer therapy. Therefore, it is very crucial to learn more about oncofertility practice in limited resource settings such as in developing countries that suffer often from shortage of healthcare services provided to young patients with cancer. METHODS: As an extrapolation during the global crisis of COVID-19 pandemic, we surveyed oncofertility centers from 14 developing countries (Egypt, Tunisia, Brazil, Peru, Panama, Mexico, Colombia, Guatemala, Argentina, Chile, Nigeria, South Africa, Saudi Arabia, and India). Survey questionnaire included questions on the availability and degree of utilization of fertility preservation options in case of childhood cancer, breast cancer, and blood cancer. RESULTS: All surveyed centers responded to all questions. Responses and their calculated oncofertility scores showed different domestic standards for oncofertility practice in case of childhood cancer, breast cancer, and blood cancer in the developing countries under limited resource settings. CONCLUSIONS: Medical practice in limited resource settings has become a critical topic especially after the global crisis of COVID-19 pandemic. Understanding the resources necessary to provide oncofertility treatments is important until the current COVID-19 pandemic resolves. Lessons learned will be valuable to future potential worldwide disruptions due to infectious diseases or other global crises.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/prevenção & controle , Atenção à Saúde/normas , Preservação da Fertilidade/métodos , Neoplasias/terapia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus/isolamento & purificação , COVID-19 , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Atenção à Saúde/economia , Países em Desenvolvimento , Feminino , Preservação da Fertilidade/economia , Preservação da Fertilidade/estatística & dados numéricos , Humanos , Neoplasias/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , SARS-CoV-2 , Inquéritos e Questionários
4.
Andrologia ; 48(2): 125-36, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25904411

RESUMO

Moringa oleifera L. is a medicinal plant with potential antioxidant property. This study was aimed at investigating the chemoprotective effect of Moringa oleifera leaf extract (MOE) on cyclophosphamide (CP)-induced testicular toxicity. Two-week-old male Swiss albino mice were intraperitoneally injected with phosphate-buffered saline, 50 mg kg(-1) of CP and 25 mg kg(-1) of MOE. In combination treatment, mice were injected with 25 mg kg(-1) of MOE 24 h prior to CP injection, 24 h prior and post-CP injection and 24 h post-CP injection for 5 consecutive days (10 mg kg(-1) ). Six weeks later, mice were sacrificed to assess epididymal sperm parameters. MOE alone did not have any significant effect on sperm parameters. However, acute injection of CP resulted in significant decline in motility (P < 0.001), increase in head abnormality (P < 0.01) and DNA damage (P < 0.05). Combining MOE with CP increased the sperm density, motility and reduced head defect and DNA damage, irrespective of the schedule and dosage of MOE. Administration of MOE prior to CP significantly elevated the level of superoxide dismutase and catalase with concomitant decrease in lipid peroxidation in the testicular tissue. In conclusion, MOE may have potential benefit in reducing the loss of male gonadal function following chemotherapy.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Antioxidantes/farmacologia , Ciclofosfamida/toxicidade , Dano ao DNA/efeitos dos fármacos , Moringa oleifera , Extratos Vegetais/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , Catalase/efeitos dos fármacos , Catalase/metabolismo , Epididimo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Folhas de Planta , Puberdade , Espermatozoides/citologia , Espermatozoides/metabolismo , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo
5.
Andrologia ; 47(8): 958-65, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25311096

RESUMO

To differentiate dead spermatozoa from viable but immotile spermatozoa, several techniques are being used during ICSI. As processed spermatozoa from poor-quality ejaculate are confronted with a higher risk of experiencing stress on exposure to altered osmotic conditions or chemicals, this study was undertaken to determine the expression of stress response gene Hsp70 and chromatin integrity in spermatozoa subjected to in situ viability assays such as hypo-osmotic swelling (HOS) test, modified hypo-osmotic swelling (M-HOS) test and pentoxifylline in 25 fresh and frozen-thawed asthenozoospermic ejaculates. RT-PCR and immunofluorescence detection of Hsp70 were performed to elucidate the expression and localisation of Hsp70 in spermatozoa, whereas DNA fragmentation analysis was performed by sperm chromatin dispersion assay. Exposure of fresh and frozen-thawed asthenozoospermic spermatozoa to M-HOS and pentoxifylline significantly increased Hsp70 expression as evidenced by increased RNA expression and immunolocalisation of Hsp70 protein in sperm head (P < 0.05-0.001). However, chromatin integrity was not significantly affected in any groups until 6 h of post-exposure time period. Our results suggest that conventional HOS may be preferred for the in situ detection of the viability as there was no immediate stress response and chromatin instability in the exposed spermatozoa.


Assuntos
Cromatina/fisiologia , Proteínas de Choque Térmico HSP70/análise , Análise do Sêmen/efeitos adversos , Motilidade dos Espermatozoides , Espermatozoides/química , Astenozoospermia/diagnóstico , Astenozoospermia/fisiopatologia , Fragmentação do DNA , Imunofluorescência , Humanos , Infertilidade Masculina/diagnóstico , Masculino , Pentoxifilina/efeitos adversos , Pentoxifilina/farmacologia , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise do Sêmen/métodos , Cabeça do Espermatozoide/química , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia
6.
Andrologia ; 44 Suppl 1: 642-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22040161

RESUMO

With increasing evidence for faulty paternal contribution to reproduction, there has been a steady increase in studies highlighting an association between sperm DNA damage, failed/delayed fertilisation and aberrant embryo development. Owing to prevailing ambiguity, the aims of the study were to analyse the genetic integrity of the male gamete and then to understand its association with age, standard semen parameters, lifestyle and occupational factors. The study included 504 subjects, attending university infertility clinic for fertility evaluation and treatment. Semen characteristics were analysed by standard criteria; terminal deoxynucelotidyl transferase-mediated nick end-labelling assay was employed for DNA damage assessment. The average incidence of sperm DNA damage in patients with normozoospermic semen parameters was <10%. Patients with oligozoospermia, severe oligozoospermia, oligoasthenoteratospermia, asthenoteratozoospermia and necrozoospermia had significantly higher level of sperm DNA damage (P < 0.001). Patients above 40 years of age had significantly high levels of DNA damage (P < 0.001) compared with their counterparts. Patients with varicocele and a history of alcohol consumption had higher incidence of spermatozoa with DNA damage (P < 0.01). Poor sperm characteristics in the ejaculate are associated with increased sperm DNA damage. Age-related increase in sperm DNA damage and association of the same with varicocele and alcohol consumption are also demonstrated.


Assuntos
Envelhecimento/genética , Dano ao DNA , Infertilidade Masculina/genética , Ocupações , Espermatozoides , Humanos , Estilo de Vida , Masculino
7.
Andrologia ; 43(6): 416-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21651599

RESUMO

The initial fraction of the human ejaculate mainly contains prostatic secretions and the subsequent fraction holds majority of the spermatozoa suspended in the secretions from the seminal vesicle. Apart from large series of proteins, human ejaculate also contains antioxidants and reactive oxygen species that are specific to certain accessory sexual glands; however, the influence of these components on the sperm DNA integrity has not been elucidated till date. The present investigation was conducted using split (first and second) ejaculate fractions of forty-one subjects having various semen abnormalities. Sperm DNA integrity was assessed in the individual fractions by comet assay and quantified. The amount of sperm DNA damage between the split fractions is not significantly different in normozoospermic semen samples. In contrast, split fraction-2 had significantly elevated level of DNA-damaged spermatozoa in asthenozoospermic (P < 0.01) and teratozoospermic groups (P < 0.001) when compared to whole ejaculate. The split fraction analysis using various types of ejaculates demonstrated the difference in sperm DNA integrity, which has not been reported till date. Hence, in a clinical point of view, the use of initial ejaculate fraction may be considered superior to whole ejaculate in assisted conception if the DNA integrity is a concern especially in asthenozoospermic and teratozoospermic samples.


Assuntos
Astenozoospermia/genética , Fragmentação do DNA , DNA/genética , Infertilidade Masculina/genética , Espermatozoides/metabolismo , Astenozoospermia/fisiopatologia , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Estudos Prospectivos
8.
Mol Hum Reprod ; 17(9): 545-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21482616

RESUMO

DNA methylation events during spermatogenesis have important implications for gamete integrity and transmission of epigenetic information to the next generation. However, the role of DNA methyltransferases in the disorders of human spermatogenesis has not been elucidated. The aim of the present study was to evaluate the expression of DNMT3B, crucial for full germ cell methylation, in testicular germ cells of patients with spermatogenic arrest and to determine whether or not there is an association with the global methylation status. In order to determine the DNMTs expression status at various stages of spermatogenesis, immunohistochemical localization was performed on 16 fertile controls having normal spermatogenesis and 11 patients with bilateral spermatogenic arrest. DNMT3B was expressed in most of the germ cell types in both controls and patients with bilateral spermatogenic arrest. The number of DNMT3B positive preleptotene/zygotene cells and pachytene spermatocytes was significantly lower in patients with bilateral arrest. However, evaluation of 5-methylcytosine, a global methylation marker, in the few matured germ cells of these patients did not reveal altered methylation. In conclusion, the global methylation status of germ cells is not affected by spermatogenic defects in spite of aberrant DNMT3B expression indicating the necessity of proper methylation for full spermatogenesis.


Assuntos
DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Células Germinativas/enzimologia , Células Germinativas/fisiologia , Oligospermia/enzimologia , Oligospermia/genética , Adulto , Animais , Azoospermia/congênito , Citosina/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Epigênese Genética , Células Germinativas/citologia , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Pessoa de Meia-Idade , Oligospermia/fisiopatologia , Espermatogênese/fisiologia , Testículo/citologia , DNA Metiltransferase 3B
9.
J Postgrad Med ; 56(4): 317-20, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20935409

RESUMO

One of the landmarks in clinical genetics is prenatal diagnosis of genetic disorders. The recent advances in the field have made it possible to diagnose the genetic conditions in the embryos before implantation in a setting of in vitro fertilization. Polymerase chain reaction and fluorescence in situ hybridization are the two common techniques employed on a single or two cells obtained via embryo biopsy. The couple who seek in vitro fertilization may screen their embryos for aneuploidy and the couple at risk for a monogenic disorder but averse to abortion of the affected fetuses after prenatal diagnosis, are likely to be the best candidates to undergo this procedure. This article reviews the technique, indications, benefits, and limitations of pre-implantation genetic testing in clinical practice.


Assuntos
Implantação do Embrião/genética , Doenças Genéticas Inatas/diagnóstico , Diagnóstico Pré-Implantação/métodos , Diagnóstico Pré-Natal/métodos , Biópsia , Aberrações Cromossômicas , Feminino , Doenças Genéticas Inatas/genética , Testes Genéticos/métodos , Humanos , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase , Gravidez
10.
Hum Exp Toxicol ; 28(4): 195-202, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19734270

RESUMO

This study presents the findings of free radical scavenging and antigenotoxic effect of hydroalcoholic extract of Cymbopogon citratus (CCE). The CCE at a concentration of 60 microg/mL resulted in a significant scavenging ability of 2,2-diphenyl-2-picryl hydrazyl (DPPH; (85%), 2,2-azinobis (3-ethyl benzothiazoline-6-sulphonic acid) (ABTS; 77%), hydroxyl (70%), superoxide (76%), nitric oxide (78%) free radicals generated using in vitro and also a moderate anti-lipid peroxidative effect (57%). Further, the radiation-induced antigenotoxic potential of CCE was assessed in Chinese hamster lung fibroblast cells (V79) using micronucleus assay. The CCE resulted in a dose-dependent decrease in the yield of radiation-induced micronuclei, with a maximum effect at 125 microg/mL CCE for 1 h before 2 Gy of radiation. Similarly, there was a significant (P < 0.05-0.0001) decrease in percentage of micronuclei when V79 cells were treated with optimal dose of CCE (125 microg/mL) before exposure to different doses of gamma radiation, that is, 0.5-4 Gy, compared with radiation alone groups. The results of the micronucleus study indicated antigenotoxic effect demonstrating the radioprotective potential of CCE and, which may partly due to its and antioxidant capacity as it presented its ability to scavenge various free radicals in vitro and anti-lipid peroxidative potential.


Assuntos
Cymbopogon/química , Dano ao DNA/efeitos da radiação , Sequestradores de Radicais Livres/farmacologia , Raios gama , Protetores contra Radiação , Animais , Linhagem Celular , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Etanol , Radicais Livres/metabolismo , Testes para Micronúcleos , Mutação/efeitos dos fármacos , Mutação/efeitos da radiação , Extratos Vegetais/farmacologia , Solventes , Espectrofotometria Ultravioleta , Água
11.
Oncogene ; 26(42): 6141-9, 2007 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-17420724

RESUMO

The early stage embryogenesis of higher eukaryotes lacks some of the damage response pathways such as G1/S checkpoint, G2/M checkpoint and apoptosis. We examined here the damage response of preimplantation stage embryos after fertilization with 6 Gy irradiated sperm. Sperm-irradiated embryos developed normally for the first 2.5 days, but started to exhibit a developmental delay at day 3.5. p21 was activated in the delayed embryos, which carried numerous micronuclei owing to delayed chromosome instability. Apoptosis was observed predominantly in the inner cell mass of the day 4.0 embryos. Sperm-irradiated p21-/- embryos lacked the delay, but chromosome instability and apoptosis were more pronounced than the corresponding p21 wild-type embryos. We conclude from the result that damage responses come in a stage-specific manner during preimplantation stage development; p53-dependent S checkpoint at the zygote stage, p21-mediated cell cycle arrest at the morula/blastocyst stages and apoptosis after the blastocyst stage in the inner cell mass.


Assuntos
Blastocisto/citologia , Blastocisto/fisiologia , Inibidor de Quinase Dependente de Ciclina p21/fisiologia , Dano ao DNA/fisiologia , Animais , Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/deficiência , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout
12.
Mutagenesis ; 21(4): 237-42, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16735450

RESUMO

Coleus aromaticus (Benth, Family: Laminaceae), Indian Oregano native to India and Mediterranean, is well known for its medicinal properties. A preliminary study was undertaken to elucidate in vitro free radical scavenging potential and inhibition of lipid peroxidation by C.aromaticus hydroalcoholic extract (CAE). Anti-clastogenic and radioprotective potential of CAE were studied using micronucleus assay after irradiating Chinese hamster fibroblast (V79) cells. CAE at 10, 20, 40, 60, 80, 100 and 120 mug/ml resulted in a dose-dependent increase in radical scavenging ability against various free radicals viz., 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide anion (O(2)(*-)), hydroxyl (OH(*)) and nitric oxide (NO(*)) generated in vitro. A maximum scavenging potential was noticed at 100 mug/ml and a saturation point was reached thereafter with the increasing doses of CAE. The free radical scavenging potential of the extract was in the order of DPPH > ABTS > Superoxide > Hydroxyl > Nitric oxide. CAE also exhibited a moderate inhibition of lipid peroxidation in vitro, with a maximum inhibition at 60 mug/ml (33%), attaining saturation at higher doses. The extract also rendered protection against radiation induced DNA damage, as evidenced by the significant (P < 0.05) decrease in the percentage of radiation-induced micronucleated cells (MN) and frequency of micronuclei (total). A maximum anticlastogneic effect/ radioprotection was noticed at a very low concentration i.e., 5 mug/ml of CAE, treated 1 h prior to 2 Gy of gamma radiation. A significant (P < 0.0001) anticlastogenic/radioprotective effect was also observed when the cells were treated with an optimum dose of CAE (5 mug/ml) 1 h prior to 0.5, 1, 2 and 4 Gy of gamma radiation compared with the respective radiation control groups. Overall, our results established an efficient antioxidant, anticlastogenic and radioprotective potential of CAE, which may be of great pharmacological importance.


Assuntos
Antioxidantes/metabolismo , Coleus/metabolismo , Raios gama , Mutagênicos , Animais , Compostos de Bifenilo , Cricetinae , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Hidrazinas , Peroxidação de Lipídeos , Testes para Micronúcleos/métodos , Óxido Nítrico/química , Fitoterapia , Picratos , Extratos Vegetais/uso terapêutico , Protetores contra Radiação/uso terapêutico
13.
Oncogene ; 25(44): 5921-32, 2006 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-16682953

RESUMO

The S-phase DNA damage checkpoint is activated by DNA damage to delay DNA synthesis allowing time to resolve the replication block. We previously discovered the p53-dependent S-phase DNA damage checkpoint in mouse zygotes fertilized with irradiated sperm. Here, we report that the same p53 dependency holds in mouse embryonic fibroblasts (MEFs) at low doses of irradiation. DNA synthesis in p53 wild-type (WT) MEFs was suppressed in a biphasic manner in which a sharp decrease below 2.5 Gy was followed by a more moderate decrease up to 10 Gy. In contrast, p53-/- MEFs exhibited radioresistant DNA synthesis below 2.5 Gy whereas the cells retained the moderate suppression above 5 Gy. DNA fiber analysis revealed that 1 Gy irradiation suppressed replication fork progression in p53 WT MEFs, but not in p53-/- MEFs. Proliferating cell nuclear antigen (PCNA), clamp loader of DNA polymerase, was phosphorylated in WT MEFs after 1 Gy irradiation and redistributed to form foci in the nuclei. In contrast, PCNA was not phosphorylated and dissociated from chromatin in 1 Gy-irradiated p53-/- MEFs. These results demonstrate that the novel low-dose-specific p53-dependent S-phase DNA damage checkpoint is likely to regulate the replication fork movement through phosphorylation of PCNA.


Assuntos
Dano ao DNA/genética , Reparo do DNA/genética , Replicação do DNA , Fase S/genética , Proteína Supressora de Tumor p53/fisiologia , Animais , Linhagem Celular Transformada , Relação Dose-Resposta à Radiação , Fibroblastos/fisiologia , Raios gama , Humanos , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Fosforilação , Antígeno Nuclear de Célula em Proliferação/metabolismo
14.
J Assist Reprod Genet ; 18(3): 160-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11411432

RESUMO

PURPOSE: To compare the effectiveness of swim-up method, using different types of semen samples. METHODS: In this retrospective study undertaken in university medical college infertility centre, subfertile couples undergoing Intra Uterine Insemination were selected. A total of 600 semen samples used for the preparation of sperm samples using swim-up method were analyzed. Relative Yield was calculated from the sperm count and motility before and after swim up from each semen sample in six different groups. RESULT(S): Statistically significant increase in relative yield was found in oligospermic samples (20.41) followed by teratospermia (16.98). However, relative yield was low in asthenospermic (11.97) and normal (> 60 million/ml) samples (11.66). CONCLUSION(S): Semen samples with good sperm count resulted in poor recovery after swim up. Swim-up method appears to be effective for oligospermic samples. Modifications like multiple tube swim up, using appropriate incubation time based on the initial semen parameter, will enhance the sperm yield after swim up.


Assuntos
Inseminação Artificial/métodos , Sêmen/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Humanos , Masculino , Estudos Retrospectivos , Sêmen/citologia , Contagem de Espermatozoides , Espermatozoides/citologia
15.
Mutat Res ; 448(1): 57-68, 2000 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-10751623

RESUMO

Effect of 20 nM vindesine sulphate (VDS) treatment was studied on cell survival, growth kinetics and micronuclei induction in V79 cells exposed to 0-300 cGy of gamma-radiation at 16, 22 and 28 h post-irradiation. Treatment of V79 cells with VDS before exposure to different doses of gamma radiation resulted in a significant decline in cell survival and growth kinetic when compared with the concurrent PBS+irradiation group. The decline in cell survival and growth kinetics was dose related. Similarly, the cell proliferation indices also declined in a dose dependent manner in both PBS+irradiation and VDS+irradiation groups and this decline was higher in VDS+irradiation group in comparison with the PBS+irradiation group. In contrast, the frequency of micronuclei increased in a dose related manner in both PBS+irradiation and VDS+irradiation groups. However, the frequency of micronuclei was significantly greater in the VDS+irradiation group when compared to the PBS+irradiation group at all the post-irradiation time periods studied and the dose response for both groups was linear for all the scoring time periods. The biological response was determined by plotting surviving fraction and micronuclei frequencies on X- and Y-axes, respectively. The plot between surviving fraction and micronuclei induction showed a close correlation. The surviving fraction of V79 cells reduced with the increasing frequency of micronuclei in both groups and the relationship between micronuclei induction and cell survival could be fitted on a linear quadratic model.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Pulmão/citologia , Pulmão/efeitos da radiação , Vindesina/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Divisão Celular/efeitos da radiação , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/efeitos da radiação , Cricetinae , Cricetulus , Relação Dose-Resposta à Radiação , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Raios gama , Pulmão/efeitos dos fármacos , Testes para Micronúcleos
16.
J Pharmacol Toxicol Methods ; 43(3): 171-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11257480

RESUMO

The aim of the present study was to formulate a simple chemically defined medium for the in vitro growth of rat two-cell embryos to blastocysts. Embryos from day 2 pregnant rats were retrieved and placed in paraffin oil-covered droplets of "rat two-cell embryo culture medium" (R2ECM) containing combinations of various serum supplements, glucose, L-glutamine, and cultured up to 96 h in a CO(2) incubator. Embryos cultured in the basic medium (R2ECM), as well as those supplemented either with fetal bovine serum (FBS) or male rat serum (MRS) did not develop beyond the two- to four-cell stage. In R2ECM with 0.3% bovine serum albumin (BSA) and 7.5 mM glucose, 44% of embryos reached the blastocyst stage by 96 h in culture, and the blastulation rate increased to about 83% when 1 mM of L-glutamine was added. To evaluate the effects of varying doses of glucose, two-cell embryos were cultured in R2ECM supplemented with 0.3% BSA, 1 mM L-glutamine, and 2.5, 5.0, or 7.5 mM of glucose. The percentage of embryos reaching the blastocyst stage for 2.5, 5.0, and 7.5 mM glucose was 64.6%, 65.3%, and 82.9%, respectively. The present study showed that the modified medium (R2ECM) is a simple chemically defined medium that is capable of supporting in vitro growth of rat two-cell embryos to blastocysts in high proportion (greater than 80%) without the need for change of medium within 96 h of culture.


Assuntos
Blastocisto/fisiologia , Desenvolvimento Embrionário e Fetal/fisiologia , Animais , Blastocisto/efeitos dos fármacos , Meios de Cultura , Técnicas de Cultura , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Feminino , Glucose/farmacologia , Glutamina/farmacologia , Gravidez , Ratos , Ratos Wistar
17.
Toxicology ; 138(1): 29-41, 1999 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-10566589

RESUMO

The genotoxic effect of 0, 1, 5, 10, 25, 50 and 100 nM teniposide (VM-26) treatment was studied on cultured V79 cells. Treatment of V79 cells with different concentrations of teniposide resulted in a concentration-dependent decline in the cell survival and growth kinetics. VM-26 treatment also caused alteration in the cell proliferation kinetics as evidenced by the increase in the frequency of mononucleate cells, with a consequent decline in the frequency of binucleate cells in a concentration-dependent manner at all the post-treatment time periods. Exposure of V79 cells to different concentrations of VM-26 resulted in a concentration related elevation in the frequency of micronucleated binucleate (MN) cells. The frequency of MN was significantly higher in VM-26 treated cells than that of non-drug treated cells at all the post-treatment time periods. A peak frequency of MN was observed at 16 h post-treatment that declined thereafter. The release of lactate dehydrogenase increased with the increase in drug concentration and a maximum LDH release was observed at 0.5 h post-treatment after exposure to 10-100 nM VM-26. While a peak value was observed at 1 and 2 h for 5 and 1 nM VM-26, respectively. The biological response was evaluated by determining the relationship between micronuclei and cell survival. The cell survival declined with increasing MN frequency, resulting in a close but an inverse relationship between the cell survival and micronuclei-induction. The dose effect relationships for micronuclei induction, LDH release and biological response was linear quadratic.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/metabolismo , Pulmão/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Teniposídeo/farmacologia , Animais , Ciclo Celular , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Clonais , Ensaio de Unidades Formadoras de Colônias , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Pulmão/citologia , Pulmão/enzimologia
18.
Toxicol Lett ; 109(1-2): 31-41, 1999 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-10514028

RESUMO

The influence of teniposide (VM-26) treatment was studied on the radiation-induced alterations in cell survival, micronuclei (MN) formation and lactate dehydrogenase (LDH) release in V79 cells. Treatment of V79 cells with 10 nM teniposide before exposure to different doses of gamma radiation resulted in a significant decline in the cell survival when compared with the PBS + irradiation group. The decline in cell survival was dose related. The cell proliferation indices also declined in a dose-dependent manner in both PBS + irradiation and VM-26 + irradiation groups. The decline was higher in the VM-26 + irradiation group in comparison with the PBS + irradiation group. In contrast, the frequency of micronuclei increased in a dose-related manner in both PBS + irradiation and VM-26 + irradiation groups. However, the frequency of micronuclei was significantly greater in the latter group when compared with the former group at all the post-irradiation time periods studied. The LDH contents increased in a dose-dependent manner in both PBS + irradiation and VM-26 + irradiation groups at all the post-irradiation time periods evaluated. This elevation in LDH contents was significantly greater in the VM-26 + irradiation group in comparison with the PBS + irradiation group.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , L-Lactato Desidrogenase/metabolismo , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Testes para Micronúcleos , Teniposídeo/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Cricetinae , Raios gama , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos
19.
Mutat Res ; 421(1): 55-63, 1998 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-9748502

RESUMO

Effect of different concentrations (0, 1, 5, 10, 20 and 50 nM) of vindesine sulphate was studied on clonogenicity and micronucleus (MN) formation in V79 (Chinese hamster lung fibroblasts) cells. Exposure of V79 cells to vindesine for 6 h resulted in a concentration dependent decline in cell survival. The frequency of micronuclei (MN) increased in a concentration dependent manner at 16, 22 and 28 h post-exposure. The frequency of MN increased significantly after 5 to 50 nM drug exposure at 16 and 22 h post-treatment, while increasing post-exposure time to 28 h resulted in a significant increase in MN frequency at all exposure doses of vindesine. The statistical evaluation of concurrent concentrations at various time periods showed a non-significant difference in MN frequency among various post-exposure time periods, except 16 h and 28 h for 50 nM, where a significant decline in the MN frequency was observed at 28 h compared to 16 h post-exposure. The cell proliferation indices showed a concentration dependent decline in the frequency of binucleate cells and this decline was linear quadratic. The increasing drug concentration resulted in a concentration dependent decline in cell survival. While the frequency of micronuclei increased the cell survival decreased and the relationship between cell survival and micronucleus induction was linear quadratic.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Mutagênicos/toxicidade , Vindesina/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular , Cricetinae , Cricetulus , Fibroblastos , Pulmão , Testes para Micronúcleos
20.
Mutat Res ; 377(1): 105-13, 1997 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9219585

RESUMO

Exposure of V79 cells to different doses of gamma-irradiation resulted in a dose-dependent decline in their survival. The treatment of cells with paclitaxel before irradiation resulted in a further decline in the cell survival. Conversely, the micronuclei frequency increased with the increasing dose of radiation in both irradiated and paclitaxel + irradiated cultures at all the three post-irradiation time periods studied. However, no significant difference among the frequencies of micronuclei was found at 16, 22 and 28 h post-exposure. The trend for cell proliferation was similar to that of cell survival. The cell proliferation declined with increasing dose of radiation. The paclitaxel treatment further reduced cell proliferation compared to the irradiated control group. The dose response for all the parameters for both groups was linear quadratic. The biological response between micronuclei induction and cell survival was also determined. The cell survival and micronuclei formation were inversely related and the correlation between cell survival and micronuclei formation (biological response) was linear quadratic for both irradiated and paclitaxel + irradiated groups.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Aberrações Cromossômicas , Raios gama , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Paclitaxel/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Cricetinae , Cricetulus , Relação Dose-Resposta à Radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Radiossensibilizantes/farmacologia
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