Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
J Neurosci ; 44(5)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38296648

RESUMEN

The molecular clock that generates daily rhythms of behavior and physiology consists of interlocked transcription-translation feedback loops. In Drosophila, the primary feedback loop involving the CLOCK-CYCLE transcriptional activators and the PERIOD-TIMELESS transcriptional repressors is interlocked with a secondary loop involving VRILLE (VRI) and PAR DOMAIN PROTEIN 1 (PDP1), a repressor and activator of Clock transcription, respectively. Whereas extensive studies have found numerous transcriptional, translational, and posttranslational modulators of the primary loop, relatively little is known about the secondary loop. In this study, using male and female flies as well as cultured cells, we demonstrate that TARANIS (TARA), a Drosophila homolog of the TRIP-Br/SERTAD family of transcriptional coregulators, functions with VRI and PDP1 to modulate the circadian period and rhythm strength. Knocking down tara reduces rhythm amplitude and can shorten the period length, while overexpressing TARA lengthens the circadian period. Additionally, tara mutants exhibit reduced rhythmicity and lower expression of the PDF neuropeptide. We find that TARA can form a physical complex with VRI and PDP1, enhancing their repressor and activator functions, respectively. The conserved SERTA domain of TARA is required to regulate the transcriptional activity of VRI and PDP1, and its deletion leads to reduced locomotor rhythmicity. Consistent with TARA's role in enhancing VRI and PDP1 activity, overexpressing tara has a similar effect on the circadian period and rhythm strength as simultaneously overexpressing vri and Pdp1 Together, our results suggest that TARA modulates circadian behavior by enhancing the transcriptional activity of VRI and PDP1.


Asunto(s)
Proteínas de Drosophila , Drosophila , Animales , Masculino , Femenino , Drosophila/fisiología , Retroalimentación , Proteínas de Drosophila/metabolismo , Ritmo Circadiano/genética , Proteínas CLOCK/genética , Drosophila melanogaster/metabolismo
2.
bioRxiv ; 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38076905

RESUMEN

The molecular clock that generates daily rhythms of behavior and physiology consists of interlocked transcription-translation feedback loops. In Drosophila, the primary feedback loop involving the CLOCK-CYCLE transcriptional activators and the PERIOD-TIMELESS transcriptional repressors is interlocked with a secondary loop involving VRILLE (VRI) and PAR DOMAIN PROTEIN 1 (PDP1), a repressor and activator of Clock transcription, respectively. Whereas extensive studies have found numerous transcriptional, translational, and post-translational modulators of the primary loop, relatively little is known about the secondary loop. In this study, using male and female flies as well as cultured cells, we demonstrate that TARANIS (TARA), a Drosophila homolog of the TRIP-Br/SERTAD family of transcriptional coregulators, functions with VRI and PDP1 to modulate the circadian period and rhythm strength. Knocking down tara reduces rhythm amplitude and can shorten the period length, while overexpressing TARA lengthens the circadian period. Additionally, tara mutants exhibit reduced rhythmicity and lower expression of the PDF neuropeptide. We find that TARA can form a physical complex with VRI and PDP1, enhancing their repressor and activator functions, respectively. The conserved SERTA domain of TARA is required to regulate the transcriptional activity of VRI and PDP1, and its deletion leads to reduced locomotor rhythmicity. Consistent with TARA's role in enhancing VRI and PDP1 activity, overexpressing tara has a similar effect on the circadian period and rhythm strength as simultaneously overexpressing vri and Pdp1. Together, our results suggest that TARA modulates circadian behavior by enhancing the transcriptional activity of VRI and PDP1.

3.
Oral Oncol ; 147: 106587, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37925894

RESUMEN

BACKGROUND: In the phase 3 KEYNOTE-040 study, pembrolizumab prolonged OS versus chemotherapy in previously treated recurrent or metastatic (R/M) HNSCC. We present a post hoc subgroup analysis by disease recurrence pattern: recurrent-only, recurrent and metastatic (recurrent-metastatic), and metastatic-only HNSCC. MATERIALS AND METHODS: Patients had HNSCC that progressed during or after platinum-containing treatment for R/M disease or had recurrence or progression within 3-6 months of previous platinum-containing definitive therapy for locally advanced disease. Patients were randomly assigned (1:1) to pembrolizumab 200 mg Q3W or investigator's choice of standards of care (SOC): methotrexate, docetaxel, or cetuximab. Outcomes included OS, PFS, ORR, and DOR. The data cutoff was May 15, 2017. RESULTS: There were 125 patients (pembrolizumab, 53; SOC, 72) in the recurrent-only subgroup, 204 in the recurrent-metastatic subgroup (pembrolizumab, 108; SOC, 96), and 166 in the metastatic-only subgroup (pembrolizumab, 86; SOC, 80). The hazard ratio (95% CI) for death for pembrolizumab versus SOC was 0.83 (0.55-1.25) in the recurrent-only, 0.78 (0.58-1.06) in the recurrent-metastatic, and 0.74 (0.52-1.05) in the metastatic-only subgroups. PFS was similar between treatment arms in all subgroups. ORR was 22.6% for pembrolizumab versus 16.7% for SOC in the recurrent-only, 10.2% versus 6.3% in the recurrent-metastatic, and 15.1% versus 8.8% in the metastatic-only subgroups. DOR was numerically longer with pembrolizumab in all subgroups. CONCLUSION: Pembrolizumab provided numerically longer OS and durable responses in all subgroups compared with SOC, suggesting that patients with previously treated R/M HNSCC benefit from pembrolizumab regardless of recurrence pattern.


Asunto(s)
Neoplasias de Cabeza y Cuello , Metotrexato , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/etiología , Cetuximab/uso terapéutico , Docetaxel/uso terapéutico , Platino (Metal)/uso terapéutico , Recurrencia Local de Neoplasia/patología , Neoplasias de Cabeza y Cuello/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
4.
Curr Biol ; 33(13): 2702-2716.e3, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37352854

RESUMEN

Sleep is essential, but animals may forgo sleep to engage in other critical behaviors, such as feeding and reproduction. Previous studies have shown that female flies exhibit decreased sleep after mating, but our understanding of the process is limited. Here, we report that postmating nighttime sleep loss is modulated by diet and sleep deprivation, demonstrating a complex interaction among sleep, reproduction, and diet. We also find that female-specific pC1 neurons and sleep-promoting dorsal fan-shaped body (dFB) neurons are required for postmating sleep plasticity. Activating pC1 neurons leads to sleep suppression on standard fly culture media but has little sleep effect on sucrose-only food. Published connectome data suggest indirect, inhibitory connections among pC1 subtypes. Using calcium imaging, we show that activating the pC1e subtype inhibits dFB neurons. We propose that pC1 and dFB neurons integrate the mating status, food context, and sleep drive to modulate postmating sleep plasticity.


Asunto(s)
Proteínas de Drosophila , Trastornos del Inicio y del Mantenimiento del Sueño , Animales , Femenino , Drosophila/fisiología , Proteínas de Drosophila/fisiología , Sueño/fisiología , Privación de Sueño , Drosophila melanogaster/fisiología
6.
Curr Biol ; 25(13): 1717-26, 2015 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-26096977

RESUMEN

Sleep is an essential and conserved behavior whose regulation at the molecular and anatomical level remains to be elucidated. Here, we identify TARANIS (TARA), a Drosophila homolog of the Trip-Br (SERTAD) family of transcriptional coregulators, as a molecule that is required for normal sleep patterns. Through a forward-genetic screen, we isolated tara as a novel sleep gene associated with a marked reduction in sleep amount. Targeted knockdown of tara suggests that it functions in cholinergic neurons to promote sleep. tara encodes a conserved cell-cycle protein that contains a Cyclin A (CycA)-binding homology domain. TARA regulates CycA protein levels and genetically and physically interacts with CycA to promote sleep. Furthermore, decreased levels of Cyclin-dependent kinase 1 (Cdk1), a kinase partner of CycA, rescue the short-sleeping phenotype of tara and CycA mutants, while increased Cdk1 activity mimics the tara and CycA phenotypes, suggesting that Cdk1 mediates the role of TARA and CycA in sleep regulation. Finally, we describe a novel wake-promoting role for a cluster of ∼14 CycA-expressing neurons in the pars lateralis (PL), previously proposed to be analogous to the mammalian hypothalamus. We propose that TARANIS controls sleep amount by regulating CycA protein levels and inhibiting Cdk1 activity in a novel arousal center.


Asunto(s)
Nivel de Alerta/fisiología , Proteína Quinasa CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclina A/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/fisiología , Sueño/fisiología , Animales , Western Blotting , Proteínas de Ciclo Celular/genética , Proteínas de Drosophila/genética , Técnicas de Silenciamiento del Gen , Neuronas/fisiología , Porción Reticular de la Sustancia Negra/citología , Porción Reticular de la Sustancia Negra/fisiología , Interferencia de ARN
7.
Fly (Austin) ; 9(4): 165-72, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26925838

RESUMEN

Sleep is essential for health and cognition, but the molecular and neural mechanisms of sleep regulation are not well understood. We recently reported the identification of TARANIS (TARA) as a sleep-promoting factor that acts in a previously unknown arousal center in Drosophila. tara mutants exhibit a dose-dependent reduction in sleep amount of up to ∼60%. TARA and its mammalian homologs, the Trip-Br (Transcriptional Regulators Interacting with PHD zinc fingers and/or Bromodomains) family of proteins, are primarily known as transcriptional coregulators involved in cell cycle progression, and contain a conserved Cyclin-A (CycA) binding homology domain. We found that tara and CycA synergistically promote sleep, and CycA levels are reduced in tara mutants. Additional data demonstrated that Cyclin-dependent kinase 1 (Cdk1) antagonizes tara and CycA to promote wakefulness. Moreover, we identified a subset of CycA expressing neurons in the pars lateralis, a brain region proposed to be analogous to the mammalian hypothalamus, as an arousal center. In this Extra View article, we report further characterization of tara mutants and provide an extended discussion of our findings and future directions within the framework of a working model, in which a network of cell cycle genes, tara, CycA, and Cdk1, interact in an arousal center to regulate sleep.


Asunto(s)
Proteína Quinasa CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclina A/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiología , Animales , Conducta Animal , Relojes Biológicos , Femenino , Masculino , Neuronas/metabolismo , Sueño
9.
Vet Rec ; 157(25): 805-10, 2005 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-16361474

RESUMEN

Outbreaks of pithomycotoxicosis (facial eczema), a hepatogenous photosensitisation caused by the mycotoxin sporidesmin, have affected ruminants in the Azores Islands of Portugal after warm, humid periods during late summer and autumn. Twenty-two outbreaks were recorded in cattle between 1999 and 2001, affecting 11.4 per cent of the animals in the affected herds, and in 2000 there was an outbreak in one sheep flock in which more than 20 per cent of the sheep died. The clinical signs included decreases in milk production, weight loss, photosensitisation and its sequelae, including death. The animals had high activities of gamma glutamyltransferase in their serum, and icterus and severe liver disease, including biliary hyperplasia and fibrosis, were found postmortem. The characteristic spores of the toxigenic saprophytic fungus Pithomyces chartarum were found on grass; all 381 isolates of the fungus were toxigenic for sporidesmin by elisa, and the results were confirmed by high-performance liquid chromatography analysis. Cattle from farms at greatest risk of pithomycotoxicosis were protected by supplementing their concentrate feed with zinc oxide, or using a slow-release intraruminal zinc bolus.


Asunto(s)
Ascomicetos/metabolismo , Brotes de Enfermedades/veterinaria , Eccema/veterinaria , Poaceae/microbiología , Rumiantes , Esporidesminas/toxicidad , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Eccema/epidemiología , Cara , Portugal/epidemiología , Estaciones del Año , Ovinos , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/microbiología , Esporas Fúngicas/aislamiento & purificación , Esporidesminas/aislamiento & purificación
10.
J Neuroimmunol ; 143(1-2): 112-5, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14575926

RESUMEN

Multiple sclerosis (MS) is common in Europe affecting up to 1:500 people. In an effort to identify genes influencing susceptibility to the disease, we have performed a population-based whole genome screen for association. In this study, 6000 microsatellite markers were typed in separately pooled DNA samples from MS patients (n=188) and matched controls (n=188). Interpretable data was obtained from 4661 of these markers. Refining analysis of the most promising markers identified 10 showing potential evidence for association.


Asunto(s)
Predisposición Genética a la Enfermedad , Pruebas Genéticas/métodos , Genoma Humano , Esclerosis Múltiple/genética , Adolescente , Adulto , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Pruebas Genéticas/estadística & datos numéricos , Humanos , Cooperación Internacional , Desequilibrio de Ligamiento/genética , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Esclerosis Múltiple/epidemiología , Portugal/epidemiología
11.
Acta Med Port ; 13(1-2): 33-8, 2000.
Artículo en Portugués | MEDLINE | ID: mdl-11059052

RESUMEN

OBJECTIVE: To find out the opinion of family doctors concerning the statutory notification of communicable diseases (SNCD) and to analyse factors associated to a good attitude towards SNCD. SETTING: Guimarães Health Centre, Guimarães. METHODS: Analytical cross-sectional study. Questionnaire survey. The 52 family doctors of the Health Centre were asked to express their opinion on some issues, including the utility of SNCD, reasons for the under-reporting of communicable diseases, up-to-dateness of the list of notifiable conditions, facility of filling in the notification form, and their own attitude towards notification. The variables utility of SNCD and attitude towards notification were then considered together with other variables (including postgraduate time, length of the family doctor's lists of patients, working in exclusivity, and how the degree of general practitioner is obtained). RESULTS: The SNCD was considered at least somewhat useful by 96% of the doctors. Thirty percent of the doctors considered excess work and/or lack of time as the main reason for under-reporting, and 29% it attributed to lack of sufficient motivation. The list of notifiable conditions was considered out dated by 46% of the doctors. Thirty eight percent of them considered the multiple notification of a case of disease not inconvenient and 54% stated that they had used it to notify all or almost all of cases they knew. The doctors who worked exclusively as civil servants and who had smaller lists of patients seemed to have a greater compliance regarding notification (p < 0.05). CONCLUSIONS: The majority of doctors considered the notification useful. They attributed the under-reporting to some conditions that are difficult to change. In this population, the doctors who worked exclusively as civil servants and who had smaller lists of patients showed a more favourable attitude towards reporting notifiable conditions.


Asunto(s)
Enfermedades Transmisibles , Medicina Familiar y Comunitaria , Adulto , Estudios Transversales , Notificación de Enfermedades , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
12.
Parassitologia ; 39(1): 65-70, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9419850

RESUMEN

Parasites present in blood samples of asymptomatic carriers and in the midgut of mosquitoes collected within a few days from the same households, have been analysed by PCR. A high prevalence (32%) of infected mosquitoes was observed and, in half of these, two parasite species were found simultaneously. The distribution of parasite species in the mosquito correlated with that found in the infected persons. Genotype patterns of Plasmodium falciparum populations were however found to be different in the two sets of samples. These results and the potential of PCR are discussed with reference to investigations of the dynamics of malaria transmission.


Asunto(s)
Anopheles/parasitología , Vectores Arácnidos/parasitología , Malaria/transmisión , Plasmodium/aislamiento & purificación , Animales , Portador Sano/parasitología , ADN Protozoario/análisis , Guinea Bissau/epidemiología , Humanos , Malaria/epidemiología , Malaria/parasitología , Plasmodium/clasificación , Plasmodium falciparum/aislamiento & purificación , Plasmodium malariae/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Especificidad de la Especie
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...