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1.
Sci Total Environ ; 878: 162832, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-36924960

RESUMEN

Marine sponges play important roles in benthic ecosystems. More than providing shelter and food to other species, they help maintain water quality by regulating nitrogen and ammonium levels in the water, and bioaccumulate heavy metals. This system, however, is particularly sensitive to sudden environmental changes including catastrophic pollution event such as oil spills. Hundreds of oil platforms are currently actively extracting oil and gas in the Gulf of Mexico. To test the vulnerability of the benthic ecosystems to oil spills, we utilized the Caribbean reef sponge, Cinachyrella alloclada, as a novel experimental indicator. We have exposed organisms to crude oil and oil dispersant for up to 24 h and measured resultant gene expression changes. Our findings indicate that 1-hour exposure to water accommodated fractions (WAF) was enough to elicit massive shifts in gene expression in sponges and host bacterial communities (8052 differentially expressed transcripts) with the up-regulation of stress related pathways, cancer related pathways, and cell integrity pathways. Genes that were upregulated included heat shock proteins, apoptosis, oncogenes (Rab/Ras, Src, CMYC), and several E3 ubiquitin ligases. 24-hour exposure of chemically enhanced WAF (CE-WAF) had the greatest impact to benthic communities, resulting in mostly downregulation of gene expression (4248 differentially expressed transcripts). Gene deregulation from 1-hour treatments follow this decreasing trend of toxicity: WAF > CE-WAF > Dispersant, while the 24-hour treatment showed a shift to CE-WAF > Dispersant > WAF in our experiments. Thus, this study supports the development of Cinachyrella alloclada as a research model organism and bioindicator species for Florida reefs and underscores the importance of developing more efficient and safer ways to remove oil in the event of a spill catastrophe.


Asunto(s)
Contaminación por Petróleo , Petróleo , Poríferos , Contaminantes Químicos del Agua , Animales , Petróleo/toxicidad , Ecosistema , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
2.
Nature ; 498(7453): 246-50, 2013 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-23728299

RESUMEN

DNA damage activates a signalling network that blocks cell-cycle progression, recruits DNA repair factors and/or triggers senescence or programmed cell death. Alterations in chromatin structure are implicated in the initiation and propagation of the DNA damage response. Here we further investigate the role of chromatin structure in the DNA damage response by monitoring ionizing-radiation-induced signalling and response events with a high-content multiplex RNA-mediated interference screen of chromatin-modifying and -interacting genes. We discover that an isoform of Brd4, a bromodomain and extra-terminal (BET) family member, functions as an endogenous inhibitor of DNA damage response signalling by recruiting the condensin II chromatin remodelling complex to acetylated histones through bromodomain interactions. Loss of this isoform results in relaxed chromatin structure, rapid cell-cycle checkpoint recovery and enhanced survival after irradiation, whereas functional gain of this isoform compacted chromatin, attenuated DNA damage response signalling and enhanced radiation-induced lethality. These data implicate Brd4, previously known for its role in transcriptional control, as an insulator of chromatin that can modulate the signalling response to DNA damage.


Asunto(s)
Ensamble y Desensamble de Cromatina , Cromatina/metabolismo , Daño del ADN , Proteínas Nucleares/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Acetilación , Adenosina Trifosfatasas/metabolismo , Puntos de Control del Ciclo Celular/efectos de la radiación , Proteínas de Ciclo Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de la radiación , Cromatina/química , Cromatina/efectos de la radiación , Ensamble y Desensamble de Cromatina/efectos de la radiación , Reparación del ADN/efectos de la radiación , Proteínas de Unión al ADN/metabolismo , Histonas/química , Histonas/metabolismo , Humanos , Lisina/química , Lisina/metabolismo , Complejos Multiproteicos/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/deficiencia , Proteínas Nucleares/genética , Fosforilación/efectos de la radiación , Factor B de Elongación Transcripcional Positiva/metabolismo , Isoformas de Proteínas/metabolismo , Radiación Ionizante , Transducción de Señal/efectos de la radiación , Factores de Transcripción/química , Factores de Transcripción/deficiencia , Factores de Transcripción/genética
3.
Fertil Steril ; 94(4): 1296-1301, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19608168

RESUMEN

OBJECTIVE: To determine pharmacokinetic profiles of two times a day and three times a day dosage regimens of Endometrin, a micronized progesterone vaginal insert for luteal support in assisted reproductive technology, compared with a gel. DESIGN: A single-center, randomized, open-label, single-day, and multiple-day (5 days) parallel design pharmacokinetic study. SETTING: University clinical research unit. PATIENT(S): Three groups of six healthy subjects, ages 18 to 40 years. INTERVENTION(S): Endometrin vaginal inserts two times a day or three times a day, or gel daily. MAIN OUTCOME MEASURE(S): Pharmacokinetic profiles. RESULT(S): Progesterone serum concentrations increased rapidly following administration of Endometrin vaginal insert, producing higher peak concentrations (Cmax) and clearing faster than gel. On the single day of dosing, mean Cmax was 17.0+/-2.7 ng/mL in the two times a day group, 19.8+/-2.9 ng/mL in the three times a day group, and 6.82+/-1.69 ng/mL in the gel group. Endometrin treatments reached steady state within the first 2 days (24-36 hours), much more rapidly than the gel, which had not reached steady state by 5 days. At 5 days, the Endometrin treatments produced sustained progesterone concentrations exceeding 10 mg/mL across 24 hours. CONCLUSIONS: Endometrin vaginal inserts reached higher Cmax, produced greater systemic exposure (area under the curve 0-24), achieved steady state more rapidly, and cleared more rapidly after termination of therapy than the comparator.


Asunto(s)
Progesterona/administración & dosificación , Progesterona/farmacocinética , Cremas, Espumas y Geles Vaginales/administración & dosificación , Cremas, Espumas y Geles Vaginales/farmacocinética , Administración Intravaginal , Adolescente , Adulto , Factores de Edad , Formas de Dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Salud , Humanos , Progesterona/sangre , Reproducción/efectos de los fármacos , Reproducción/fisiología , Técnicas Reproductivas Asistidas , Factores de Tiempo , Adulto Joven
4.
Fertil Steril ; 91(6): 2445-50, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18555224

RESUMEN

OBJECTIVE: To evaluate vaginal compared to intramuscular (IM) progesterone supplementation for luteal phase support after in vitro fertilization and embryo transfer (IVF-ET). DESIGN: Retrospective matched-samples comparative study. SETTING: Private infertility center. PATIENTS(S): Two hundred forty patients undergoing IVF-ET. INTERVENTION(S): Patients received either vaginal progesterone supplementation in the form of Endometrin 100 mg twice a day (n = 12), Endometrin 100 mg three times a day (n = 11), or Crinone 8% gel 90 mg every day (n = 17), or 50 mg every day IM progesterone in oil (n = 200). MAIN OUTCOME MEASURE(S): Clinical intrauterine pregnancy rates, pregnancy loss, and live birth rates. RESULT(S): Among patients using vaginal progesterone, there were no statistically significant differences in patient characteristics and clinical outcomes, regardless of the type of vaginal progesterone used. There were no differences in outcomes between the vaginal and IM progesterone treatment groups. There were 20 pregnancies (50.0%) among patients treated with vaginal progesterone and 103 pregnancies (51.5%) among matched IM progesterone patients. The live birth rates were 47% in the IM versus 47.5% in the vaginal progesterone groups. There were no statistically significant differences in miscarriage rates between groups. CONCLUSION(S): There are no significant differences in treatment outcomes between vaginal and IM progesterone supplementation, yielding similar clinical pregnancy, miscarriage, and live birth rates.


Asunto(s)
Transferencia de Embrión/métodos , Fertilización In Vitro/métodos , Progesterona/uso terapéutico , Aborto Espontáneo/epidemiología , Tasa de Natalidad , Femenino , Humanos , Recién Nacido , Inyecciones , Inyecciones Intramusculares , Embarazo , Resultado del Embarazo , Progesterona/administración & dosificación , Vagina
5.
Fertil Steril ; 91(4): 1012-7, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18371963

RESUMEN

OBJECTIVE: To assess the efficacy and safety of a vaginal progesterone (P(4)) insert (Endometrin) for luteal support for assisted reproductive technology (ART). DESIGN: Multicenter, randomized, open-label (assessor-blinded) phase III clinical trial. SETTING: Twenty-five U.S. ART centers. PATIENT(S): A total of 1,211 ART patients randomized to three groups: Endometrin 100 mg twice daily (n = 404), Endometrin 100 mg three times daily (n = 404), and P(4) 90 mg 8% gel daily (n = 403). INTERVENTION(S): In vitro fertilization and ET were performed according to site-specific protocols. The day after oocyte retrieval, Endometrin or vaginal P(4) gel was begun for luteal support and continued for up to 10 weeks of pregnancy. MAIN OUTCOME MEASURE(S): Biochemical, clinical, and ongoing pregnancy and live birth rates. RESULT(S): Pregnancy rates were high and similar in all treatment groups, with biochemical rates exceeding 50%, clinical and ongoing rates >or=40%, and live birth rates at 35%-38%. The adverse event profiles were similar across groups. CONCLUSION(S): Pregnancy rates and live birth rates for Endometrin (twice daily and three times daily) were high and similar to those for P(4) gel. The adverse event profiles for both were similar to that for P(4) gel and primarily due to IVF stimulation and oocyte retrieval. Endometrin was safe and well tolerated.


Asunto(s)
Fertilización In Vitro/métodos , Dispositivos Intrauterinos Medicados , Fase Luteínica/efectos de los fármacos , Menotropinas/administración & dosificación , Inducción de la Ovulación/métodos , Progesterona/administración & dosificación , Urofolitropina/administración & dosificación , Adolescente , Adulto , Combinación de Medicamentos , Femenino , Fármacos para la Fertilidad Femenina/administración & dosificación , Fármacos para la Fertilidad Femenina/efectos adversos , Humanos , Dispositivos Intrauterinos Medicados/efectos adversos , Menotropinas/efectos adversos , Inducción de la Ovulación/efectos adversos , Embarazo , Índice de Embarazo , Progesterona/efectos adversos , Progesterona/uso terapéutico , Método Simple Ciego , Resultado del Tratamiento , Urofolitropina/efectos adversos , Adulto Joven
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