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3.
J Assist Reprod Genet ; 39(8): 1693-1712, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35870095

RESUMEN

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.


Asunto(s)
COVID-19 , Preservación de la Fertilidad , Neoplasias , COVID-19/epidemiología , Humanos , Pandemias
4.
Braz J Med Biol Res ; 54(9): e11097, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34133540

RESUMEN

Pediatric epilepsy comprises chronic neurological disorders characterized by recurrent seizures. Sodium valproate is one of the common antiseizure medications used for treatment. Glucuronide conjugation is the major metabolic pathway of sodium valproate, carried out by the enzyme uridine 5'-diphosphate (UDP) glucuronosyl transferase (UGT) whose gene polymorphisms may alter the clinical outcome. The objective of this study was to assess the association between UGT1A6 genetic polymorphism and clinical outcome in terms of efficacy and tolerability in pediatric epileptic patients on sodium valproate monotherapy. Pediatric epileptic patients (n=65) aged 2-18 years receiving sodium valproate monotherapy for the past one month were included. Genetic polymorphism patterns of UGT1A6 (T19G, A541G, A552C) were evaluated by PCR-RFLP. Clinical outcome was seizure control during the 6 months observation period. Tolerability was measured by estimating the hepatic, renal, and other lab parameters. Out of 65 patients, TT (40%), TG (57%), and GG (3%) patterns were observed in UGT1A6 (T19G) gene, AA (51%), AG (40%), and GG (9%) in (A541G) gene, and AA (43%), AC (43%), and CC (14%) in (A552C) gene. No statistical difference in clinical outcome was found for different UGT1A6 genetic polymorphism patterns. We concluded that different patterns of UGT1A6 genetic polymorphism were not associated with the clinical outcome of sodium valproate in terms of efficacy and tolerability. Sodium valproate was well-tolerated among pediatric patients with epilepsy and can be used as an effective antiseizure medication.


Asunto(s)
Epilepsia , Ácido Valproico , Anticonvulsivantes/uso terapéutico , Niño , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Humanos , Polimorfismo de Nucleótido Simple , Convulsiones/tratamiento farmacológico , Convulsiones/genética , Ácido Valproico/uso terapéutico
5.
Braz. j. med. biol. res ; 54(9): e11097, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1278588

RESUMEN

Pediatric epilepsy comprises chronic neurological disorders characterized by recurrent seizures. Sodium valproate is one of the common antiseizure medications used for treatment. Glucuronide conjugation is the major metabolic pathway of sodium valproate, carried out by the enzyme uridine 5′-diphosphate (UDP) glucuronosyl transferase (UGT) whose gene polymorphisms may alter the clinical outcome. The objective of this study was to assess the association between UGT1A6 genetic polymorphism and clinical outcome in terms of efficacy and tolerability in pediatric epileptic patients on sodium valproate monotherapy. Pediatric epileptic patients (n=65) aged 2-18 years receiving sodium valproate monotherapy for the past one month were included. Genetic polymorphism patterns of UGT1A6 (T19G, A541G, A552C) were evaluated by PCR-RFLP. Clinical outcome was seizure control during the 6 months observation period. Tolerability was measured by estimating the hepatic, renal, and other lab parameters. Out of 65 patients, TT (40%), TG (57%), and GG (3%) patterns were observed in UGT1A6 (T19G) gene, AA (51%), AG (40%), and GG (9%) in (A541G) gene, and AA (43%), AC (43%), and CC (14%) in (A552C) gene. No statistical difference in clinical outcome was found for different UGT1A6 genetic polymorphism patterns. We concluded that different patterns of UGT1A6 genetic polymorphism were not associated with the clinical outcome of sodium valproate in terms of efficacy and tolerability. Sodium valproate was well-tolerated among pediatric patients with epilepsy and can be used as an effective antiseizure medication.


Asunto(s)
Humanos , Niño , Ácido Valproico/uso terapéutico , Epilepsia/genética , Epilepsia/tratamiento farmacológico , Convulsiones/genética , Convulsiones/tratamiento farmacológico , Polimorfismo de Nucleótido Simple , Anticonvulsivantes/uso terapéutico
6.
J Assist Reprod Genet ; 37(7): 1567-1577, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32594284

RESUMEN

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.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/prevención & control , Atención a la Salud/normas , Preservación de la Fertilidad/métodos , Neoplasias/terapia , Pandemias/prevención & control , Neumonía Viral/prevención & control , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Atención a la Salud/economía , Países en Desarrollo , Femenino , Preservación de la Fertilidad/economía , Preservación de la Fertilidad/estadística & datos numéricos , Humanos , Neoplasias/virología , Neumonía Viral/transmisión , Neumonía Viral/virología , SARS-CoV-2 , Encuestas y Cuestionarios
7.
Sci Rep ; 9(1): 6576, 2019 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-31036829

RESUMEN

Degradation mechanisms leading to deterioration in the battery performance is an inevitable phenomenon. Although there are detailed physics and equivalent circuit based models to predict the losses incurred due to degradation in estimating the health of the battery, they are either incomplete, computationally expensive or both. In this study, we present a very simple and elegant, chemistry independent mathematical analysis, which accurately calculates resistive and capacitive components of cycle-life related losses in a battery system. We demonstrate that discharge profiles obtained at any given degradation state of the battery can be represented by an analytical function, with its origin lying at the heart of battery dynamics, using simple parameter fitting. The model parameters relate to the battery electrochemical potential, resistance and capacity. We first validate our protocol using simulated cycling data from a degrading lithium-ion battery system modeled with detailed electrochemical thermal calculations and show that the estimates of capacity and power fades are >99% accurate using our method. Further, we construct a unique phase space plot of normalized energy, power that gives a compact representation of quantitative and qualitative trend of the degradation state of the system, as well as available power and energy.

8.
Andrologia ; 48(2): 125-36, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25904411

RESUMEN

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.


Asunto(s)
Antineoplásicos Alquilantes/toxicidad , Antioxidantes/farmacología , Ciclofosfamida/toxicidad , Daño del ADN/efectos de los fármacos , Moringa oleifera , Extractos Vegetales/farmacología , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Animales , Catalasa/efectos de los fármacos , Catalasa/metabolismo , Epidídimo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Hojas de la Planta , Pubertad , Espermatozoides/citología , Espermatozoides/metabolismo , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/metabolismo
9.
Andrologia ; 47(8): 958-65, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25311096

RESUMEN

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.


Asunto(s)
Cromatina/fisiología , Proteínas HSP70 de Choque Térmico/análisis , Análisis de Semen/efectos adversos , Motilidad Espermática , Espermatozoides/química , Astenozoospermia/diagnóstico , Astenozoospermia/fisiopatología , Fragmentación del ADN , Técnica del Anticuerpo Fluorescente , Humanos , Infertilidad Masculina/diagnóstico , Masculino , Pentoxifilina/efectos adversos , Pentoxifilina/farmacología , Estudios Prospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Semen/métodos , Cabeza del Espermatozoide/química , Motilidad Espermática/fisiología , Espermatozoides/fisiología
10.
Clin Radiol ; 69(7): 709-14, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24709093

RESUMEN

AIM: To prospectively determine efficacy and complication rates following an ultra-low dose (ULD) protocol for computed tomography (CT)-guided percutaneous needle biopsy (PNB) of lung lesions. MATERIALS AND METHODS: The use of an ULD protocol (100 kV, 7.5 mAs) for CT-guided lung biopsy was initiated, as a quality assurance initiative. All patients who underwent lung lesion biopsies under ULD were evaluated prospectively. For the purposes of comparison, a retrospective review was conducted to obtain data from patients who underwent the standard-dose protocol for CT-guided PNB of lung lesions. Total dose received, length of procedure, technical success, and complications were evaluated. RESULTS: The overall technical success rate using the ULD protocol was 95.8%. There was a statistically significant 57.5% reduction in radiation dose in the ULD group. There was no significant difference in average length of procedure between the two groups. Complication rates between the two groups were comparable, with 42% in the standard-dose group and 32% in the ULD group; no major complications occurred. Within the ULD group, smaller sized lesions were found to be correlated with higher complication rates, but lesion size had no effect on the total dose of radiation received. CONCLUSION: Radiation dose to the chest during CT-guided lung PNB is reduced significantly by 57.5% through the use of an ULD protocol. Reducing the CT radiation dose does not negatively impact patient safety or biopsy diagnostic rates in PNB.


Asunto(s)
Enfermedades Pulmonares/patología , Pulmón/patología , Nódulos Pulmonares Múltiples/patología , Dosis de Radiación , Nódulo Pulmonar Solitario/patología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja/métodos , Estudios de Factibilidad , Femenino , Humanos , Biopsia Guiada por Imagen/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiografía Intervencional/métodos , Estudios Retrospectivos
11.
Phys Rev Lett ; 108(3): 037206, 2012 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-22400782

RESUMEN

We present a detailed study of magnetism in LuFe(2)O(4), combining magnetization measurements with neutron and soft x-ray diffraction. The magnetic phase diagram in the vicinity of T(N) involves a metamagnetic transition separating an antiferro- and a ferrimagnetic phase. For both phases the spin structure is refined by neutron diffraction. Observed diffuse magnetic scattering far above T(N) is explained in terms of near degeneracy of the magnetic phases.

12.
Andrologia ; 44 Suppl 1: 642-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22040161

RESUMEN

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.


Asunto(s)
Envejecimiento/genética , Daño del ADN , Infertilidad Masculina/genética , Ocupaciones , Espermatozoides , Humanos , Estilo de Vida , Masculino
13.
Andrologia ; 43(6): 416-21, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21651599

RESUMEN

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.


Asunto(s)
Astenozoospermia/genética , Fragmentación del ADN , ADN/genética , Infertilidad Masculina/genética , Espermatozoides/metabolismo , Astenozoospermia/fisiopatología , Humanos , Infertilidad Masculina/fisiopatología , Masculino , Estudios Prospectivos
14.
Mol Hum Reprod ; 17(9): 545-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21482616

RESUMEN

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.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN , Células Germinativas/enzimología , Células Germinativas/fisiología , Oligospermia/enzimología , Oligospermia/genética , Adulto , Animales , Azoospermia/congénito , Citosina/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Epigénesis Genética , Células Germinativas/citología , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Persona de Mediana Edad , Oligospermia/fisiopatología , Espermatogénesis/fisiología , Testículo/citología , ADN Metiltransferasa 3B
15.
J Postgrad Med ; 56(4): 317-20, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20935409

RESUMEN

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.


Asunto(s)
Implantación del Embrión/genética , Enfermedades Genéticas Congénitas/diagnóstico , Diagnóstico Preimplantación/métodos , Diagnóstico Prenatal/métodos , Biopsia , Aberraciones Cromosómicas , Femenino , Enfermedades Genéticas Congénitas/genética , Pruebas Genéticas/métodos , Humanos , Hibridación Fluorescente in Situ , Reacción en Cadena de la Polimerasa , Embarazo
16.
Hum Exp Toxicol ; 28(4): 195-202, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19734270

RESUMEN

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.


Asunto(s)
Cymbopogon/química , Daño del ADN/efectos de la radiación , Depuradores de Radicales Libres/farmacología , Rayos gamma , Protectores contra Radiación , Animales , Línea Celular , Cricetinae , Cricetulus , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Etanol , Radicales Libres/metabolismo , Pruebas de Micronúcleos , Mutación/efectos de los fármacos , Mutación/efectos de la radiación , Extractos Vegetales/farmacología , Solventes , Espectrofotometría Ultravioleta , Agua
17.
Oncogene ; 26(42): 6141-9, 2007 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-17420724

RESUMEN

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.


Asunto(s)
Blastocisto/citología , Blastocisto/fisiología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , Daño del ADN/fisiología , Animales , Ciclo Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/deficiencia , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Femenino , Masculino , Ratones , Ratones Endogámicos ICR , Ratones Noqueados
18.
Indian J Cancer ; 43(4): 151-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17192685

RESUMEN

UNLABELLED: Oropharynx is an important site of cancer in India. Global comparison indicates higher incidences in India. Radiotherapy remains an important treatment modality. Efforts to improve loco-regional treatment and prolong survival are areas of focus. Radiosensitizers in hypoxic tumors have shown promise. AIM: To study the safety and radiosensitizing efficacy of sanazole in oropharyngeal squamous cell carcinoma (stage T2-4, N0-3, M0) as phase-II double blind controlled trial in patients treated with conventional radiotherapy. SETTINGS AND DESIGN: Single institutional, randomized, double-blind, placebo-controlled trial. MATERIALS AND METHODS: Group 1 (control; n = 23) received normal saline infusion, group 2 (test; n = 23) received sanazole biweekly 1.25 g intravenous infusion 15 minutes before radiotherapy. Surrogate end points of efficacy were tumor and nodal size; safety parameters were mucositis, salivary and skin reactions, dysphagia, vomiting, dysgeusia and neurological deficit. Investigators blinded to the trial evaluated patients, weekly during treatment for six weeks and thereafter monthly for three months. STATISTICAL METHODS: Non-parametric, Friedman's, Chi square, Mann-Whitney U tests. RESULTS: In the test, 15 (65%) patients had complete response, five (22%) partial/no response, two (9%) died, one (4%) lost to follow up. In the control, five (22%) patients had complete response, 16 (70%) partial/no response, one (4%) died, one (4%) lost to follow up. Short-term loco-regional response was better in the test (DF = 3, 95% Confidence Interval 0.418, 0.452, P = 0.0048). In the test group significant vomiting and one case of grade 3 neurological deficit was observed. CONCLUSION: The study validates the usefulness of sanazole for initial loco-regional control in oropharyngeal cancers.


Asunto(s)
Neoplasias Orofaríngeas/tratamiento farmacológico , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Triazoles/uso terapéutico , Adulto , Anciano , Terapia Combinada , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/cirugía , Resultado del Tratamiento
19.
Mutagenesis ; 21(4): 237-42, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16735450

RESUMEN

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.


Asunto(s)
Antioxidantes/metabolismo , Coleus/metabolismo , Rayos gamma , Mutágenos , Animales , Compuestos de Bifenilo , Cricetinae , Relación Dosis-Respuesta a Droga , Fibroblastos/metabolismo , Hidrazinas , Peroxidación de Lípido , Pruebas de Micronúcleos/métodos , Óxido Nítrico/química , Fitoterapia , Picratos , Extractos Vegetales/uso terapéutico , Protectores contra Radiación/uso terapéutico
20.
Oncogene ; 25(44): 5921-32, 2006 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-16682953

RESUMEN

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.


Asunto(s)
Daño del ADN/genética , Reparación del ADN/genética , Replicación del ADN , Fase S/genética , Proteína p53 Supresora de Tumor/fisiología , Animales , Línea Celular Transformada , Relación Dosis-Respuesta en la Radiación , Fibroblastos/fisiología , Rayos gamma , Humanos , Ratones , Ratones Endogámicos ICR , Ratones Noqueados , Fosforilación , Antígeno Nuclear de Célula en Proliferación/metabolismo
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