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1.
Nucleic Acids Res ; 52(5): 2389-2415, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38224453

RESUMO

DNA damage represents a challenge for cells, as this damage must be eliminated to preserve cell viability and the transmission of genetic information. To reduce or eliminate unscheduled chemical modifications in genomic DNA, an extensive signaling network, known as the DNA damage response (DDR) pathway, ensures this repair. In this work, and by means of a proteomic analysis aimed at studying the STIM1 protein interactome, we have found that STIM1 is closely related to the protection from endogenous DNA damage, replicative stress, as well as to the response to interstrand crosslinks (ICLs). Here we show that STIM1 has a nuclear localization signal that mediates its translocation to the nucleus, and that this translocation and the association of STIM1 to chromatin increases in response to mitomycin-C (MMC), an ICL-inducing agent. Consequently, STIM1-deficient cell lines show higher levels of basal DNA damage, replicative stress, and increased sensitivity to MMC. We show that STIM1 normalizes FANCD2 protein levels in the nucleus, which explains the increased sensitivity of STIM1-KO cells to MMC. This study not only unveils a previously unknown nuclear function for the endoplasmic reticulum protein STIM1 but also expands our understanding of the genes involved in DNA repair.


Assuntos
Núcleo Celular , Dano ao DNA , Molécula 1 de Interação Estromal , Cromatina/genética , Reparo do DNA , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Mitomicina/farmacologia , Proteômica , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismo , Humanos , Núcleo Celular/metabolismo , Proteínas de Neoplasias/metabolismo
2.
Neurobiol Dis ; 195: 106488, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565397

RESUMO

Given their highly polarized morphology and functional singularity, neurons require precise spatial and temporal control of protein synthesis. Alterations in protein translation have been implicated in the development and progression of a wide range of neurological and neurodegenerative disorders, including Huntington's disease (HD). In this study we examined the architecture of polysomes in their native brain context in striatal tissue from the zQ175 knock-in mouse model of HD. We performed 3D electron tomography of high-pressure frozen and freeze-substituted striatal tissue from HD models and corresponding controls at different ages. Electron tomography results revealed progressive remodelling towards a more compacted polysomal architecture in the mouse model, an effect that coincided with the emergence and progression of HD related symptoms. The aberrant polysomal architecture is compatible with ribosome stalling phenomena. In fact, we also detected in the zQ175 model an increase in the striatal expression of the stalling relief factor EIF5A2 and an increase in the accumulation of eIF5A1, eIF5A2 and hypusinated eIF5A1, the active form of eIF5A1. Polysomal sedimentation gradients showed differences in the relative accumulation of 40S ribosomal subunits and in polysomal distribution in striatal samples of the zQ175 model. These findings indicate that changes in the architecture of the protein synthesis machinery may underlie translational alterations associated with HD, opening new avenues for understanding the progression of the disease.


Assuntos
Modelos Animais de Doenças , Doença de Huntington , Polirribossomos , Ribossomos , Animais , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Doença de Huntington/genética , Camundongos , Polirribossomos/metabolismo , Ribossomos/metabolismo , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Camundongos Transgênicos , Progressão da Doença , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Fatores de Iniciação de Peptídeos/genética
3.
Strahlenther Onkol ; 200(8): 691-697, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38416163

RESUMO

PURPOSE: To evaluate the impact of sustained hypogonadism after androgen deprivation therapy (ADT) associated with radiotherapy in prostate cancer (PCa) patients with biochemical relapse-free survival (bRFS). METHODS: A retrospective cohort analysis of 213 consecutive PCa patients referred for radiotherapy plus ADT was carried out. Follow-up times including time to testosterone recovery (TTR) and bRFS were calculated from the end of ADT. Univariate and multivariate Cox regression analyses predicting bRFS were used. The optimal cutoffs for TTR and duration of ADT were determined using the maximally selected rank statistics (MSRS). RESULTS: After a median follow-up of 104 months, 18 patients relapsed among those who had recovered testosterone levels and 9 among those who did not. Median ADT duration was 36 months. The optimal cutoff for TTR was determined using MSRS. TTR >48 months was significantly associated with better bRFS (logrank, p < 0.0027). Five-year bRFS was 100% for >48 months vs. 85% for <48 months. TTR was the only significant variable for bRFS in multivariate Cox analysis. CONCLUSION: Our data show an association between longer TTR and bRFS values among PCa patients treated with ADT.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Testosterona , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/tratamento farmacológico , Antagonistas de Androgênios/uso terapêutico , Idoso , Testosterona/sangue , Testosterona/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Hipogonadismo/etiologia , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Resultado do Tratamento , Estudos de Coortes , Terapia Combinada , Seguimentos
4.
Nat Genet ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075208

RESUMO

Many drug discovery projects are started but few progress fully through clinical trials to approval. Previous work has shown that human genetics support for the therapeutic hypothesis increases the chance of trial progression. Here, we applied natural language processing to classify the free-text reasons for 28,561 clinical trials that stopped before their endpoints were met. We then evaluated these classes in light of the underlying evidence for the therapeutic hypothesis and target properties. We found that trials are more likely to stop because of a lack of efficacy in the absence of strong genetic evidence from human populations or genetically modified animal models. Furthermore, certain trials are more likely to stop for safety reasons if the drug target gene is highly constrained in human populations and if the gene is broadly expressed across tissues. These results support the growing use of human genetics to evaluate targets for drug discovery programs.

5.
Front Psychol ; 15: 1368336, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952829

RESUMO

The purpose of this study was to analyze the relationships between cybervictimization in social networks, problematic smartphone use, aggressive behaviors, and prosocial altruistic tendencies in young adults. The sample consisted of 601 young adults (mean age = 19.96 years; SD = 2.27; 69.1% female) who were administered online assessments of experiences of humiliation on networks, problematic smartphone use, prosocial altruistic tendencies, and aggressiveness. Results indicated significant indirect effects of cyber victimization on aggressiveness and prosocial altruistic tendencies through problematic smartphone use. Problematic cell phone use explained the relationships between online humiliation and aggressive and prosocial altruistic behaviors. The results confirmed the positive relationship between cybervictimization and problematic cell phone use, consistent with previous research. However, the negative relationship between cybervictimization and altruistic prosocial tendencies was not corroborated. The findings emphasize the need to promote actions that foster social connectedness and interdependence among young individuals to develop their identity within the community.

6.
Viruses ; 16(2)2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38399981

RESUMO

Alphaviruses can replicate in arthropods and in many vertebrate species including humankind, but only in vertebrate cells do infections with these viruses result in a strong inhibition of host translation and transcription. Translation shutoff by alphaviruses is a multifactorial process that involves both host- and virus-induced mechanisms, and some of them are not completely understood. Alphavirus genomes contain cis-acting elements (RNA structures and dinucleotide composition) and encode protein activities that promote the translational and transcriptional resistance to type I IFN-induced antiviral effectors. Among them, IFIT1, ZAP and PKR have played a relevant role in alphavirus evolution, since they have promoted the emergence of multiple viral evasion mechanisms at the translational level. In this review, we will discuss how the adaptations of alphaviruses to vertebrate hosts likely involved the acquisition of new features in viral mRNAs and proteins to overcome the effect of type I IFN.


Assuntos
Alphavirus , Interferon Tipo I , Animais , Alphavirus/fisiologia , Linhagem Celular , Interferon Tipo I/genética , Vertebrados , Tropismo , Antivirais/farmacologia , Replicação Viral
7.
Nat Struct Mol Biol ; 31(3): 455-464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38287194

RESUMO

Eukaryotic translation initiation involves recruitment of the 43S pre-initiation complex to the 5' end of mRNA by the cap-binding complex eIF4F, forming the 48S translation initiation complex (48S), which then scans along the mRNA until the start codon is recognized. We have previously shown that eIF4F binds near the mRNA exit channel of the 43S, leaving open the question of how mRNA secondary structure is removed as it enters the mRNA channel on the other side of the 40S subunit. Here we report the structure of a human 48S that shows that, in addition to the eIF4A that is part of eIF4F, there is a second eIF4A helicase bound at the mRNA entry site, which could unwind RNA secondary structures as they enter the 48S. The structure also reveals conserved interactions between eIF4F and the 43S, probaby explaining how eIF4F can promote mRNA recruitment in all eukaryotes.


Assuntos
Fator de Iniciação 4F em Eucariotos , Iniciação Traducional da Cadeia Peptídica , Humanos , Fator de Iniciação 4F em Eucariotos/genética , Fator de Iniciação 4F em Eucariotos/metabolismo , RNA Mensageiro/metabolismo , Códon de Iniciação/metabolismo , Ribossomos/metabolismo , DNA Helicases/metabolismo , Biossíntese de Proteínas , Fator de Iniciação 4A em Eucariotos/química , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo
8.
Clin Neuropsychol ; : 1-24, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965831

RESUMO

OBJECTIVE: Drug-resistant temporal lobe epilepsy (TLE) is a neurological disorder characterized by cognitive deficits. This study examined whether patients with TLE and different cognitive phenotypes differ in cortisol levels and affectivity while controlling for demographic and clinical variables. Methods: In this cross-sectional study, 79 adults with TLE underwent neuropsychological evaluation in which memory, language, attention/processing speed, executive function, and affectivity were assessed. Six saliva samples were collected in the afternoon to examine the ability of the hypothalamic-pituitary-adrenal (HPA) axis to descend according to the circadian rhythm (C1 to C6). The cortisol area under the curve concerning ground (AUCg) was computed to examine global cortisol secretion. RESULTS: Three cognitive phenotypes were identified: memory impairment, generalized impairment, and no impairment. The memory-impairment phenotype showed higher cortisol levels at C4, C5, and C6 than the other groups (p = 0.03, η2 = 0.06), higher cortisol AUCg than the generalized-impairment phenotype (p = 0.004, η2 = 0.14), and a significant reduction in positive affectivity after the evaluation (p = 0.026, η2 = 0.11). Higher cortisol AUCg and reductions in positive affectivity were significant predictors of the memory-impairment phenotype (p < 0.001; Cox and Snell R2 = 0.47). CONCLUSIONS: Patients with memory impairment had a slower decline in cortisol levels in the afternoon, which could be interpreted as an inability of the HPA axis to inhibit itself. Thus, chronic stress may influence hippocampus-dependent cognitive function more than other cognitive functions in patients with TLE.

9.
Nat Commun ; 15(1): 6633, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117603

RESUMO

Translation is regulated mainly in the initiation step, and its dysregulation is implicated in many human diseases. Several proteins have been found to regulate translational initiation, including Pdcd4 (programmed cell death gene 4). Pdcd4 is a tumor suppressor protein that prevents cell growth, invasion, and metastasis. It is downregulated in most tumor cells, while global translation in the cell is upregulated. To understand the mechanisms underlying translational control by Pdcd4, we used single-particle cryo-electron microscopy to determine the structure of human Pdcd4 bound to 40S small ribosomal subunit, including Pdcd4-40S and Pdcd4-40S-eIF4A-eIF3-eIF1 complexes. The structures reveal the binding site of Pdcd4 at the mRNA entry site in the 40S, where the C-terminal domain (CTD) interacts with eIF4A at the mRNA entry site, while the N-terminal domain (NTD) is inserted into the mRNA channel and decoding site. The structures, together with quantitative binding and in vitro translation assays, shed light on the critical role of the NTD for the recruitment of Pdcd4 to the ribosomal complex and suggest a model whereby Pdcd4 blocks the eIF4F-independent role of eIF4A during recruitment and scanning of the 5' UTR of mRNA.


Assuntos
Proteínas Reguladoras de Apoptose , Microscopia Crioeletrônica , Ligação Proteica , RNA Mensageiro , Proteínas de Ligação a RNA , Subunidades Ribossômicas Menores de Eucariotos , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/química , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Subunidades Ribossômicas Menores de Eucariotos/genética , Sítios de Ligação , Biossíntese de Proteínas , Fator de Iniciação 4A em Eucariotos/metabolismo , Fator de Iniciação 4A em Eucariotos/genética , Modelos Moleculares
10.
Artigo em Inglês | MEDLINE | ID: mdl-38740330

RESUMO

INTRODUCTION: Obesity is a global pandemic associated with various cardio-metabolic and psychiatric disorders. Neurocognitive and functional deficits have been associated with several somatic and psychiatric disorders. Adiposity-related inflammation has recently emerged as a key risk factor for neurocognitive and functional impairments. This prospective transdiagnostic study aimed to investigate the role of adiposity-related inflammatory markers in neurocognitive and functional outcomes associated with weight changes. METHODS: Peripheral blood inflammatory and oxidative stress biomarkers and neurocognitive and functional performance were assessed twice over 1 year in 165 individuals, including 30 with schizophrenia, 42 with bipolar disorder, 35 with major depressive disorder, 30 with type 2 diabetes mellitus (T2DM), and 28 healthy controls. Participants were stratified by body mass index into categories of type 2 obesity (T2OB; n=30), type 1 obesity (T1OB; n=42), overweight (OW; n=53), and average weight (NW; n=40). Mixed one-way analysis of covariance and linear and binary logistic regression analyses were performed. RESULTS: Compared with NW, T2OB and T1OB were significantly associated with impaired neurocognitive and functional performance (p<0.01; η2p=0.06-0.12) and higher levels of C-reactive protein and platelets (PLT) (p<0.01; η2p=0.08-0.16), with small-to-moderate effect sizes. IL-6, IL-10, and PLT were key factors for detecting significant weight changes in T1OB and T2OB over time. Regression models revealed that inflammatory and oxidative stress biomarkers and cellular adhesion molecules were significantly associated with neurocognitive and functional performance (p<0.05). DISCUSSION: Obesity is characterized by neurocognitive and functional impairments alongside low-grade systemic inflammation. Adiposity-related inflammatory biomarkers may contribute to neurocognitive and functional decline in individuals with T2DM and psychiatric disorders. Our data suggest that these biomarkers facilitate the identification of specific subgroups of individuals at higher risk of developing obesity.

11.
Oncología (Guayaquil) ; 33(3): [266-272], 2023.
Artigo em Inglês, Espanhol | LILACS | ID: biblio-1531956

RESUMO

Introducción:La inmunoterapia con pembrolizumab ha mejorado el pronóstico del cáncer de pulmón metastásico. En el presente caso se presenta la supervivencia extendidad y evolución de un paciente específico.Caso clínico:Hombre de 66 años, fumador. Diagnosticado de masa pulmonar en lóbulo infe-rior izquierdo de dimensiones 9 x 8 cm, con metástasis supra e infratentoriales intraaxiliares. Taller diagnóstico: Establecida como neoplasia de pulmón en estadio IVc, se comprobó el estado de PDL1 que positivo en un 80 % de la muestra de masa pulmonar. Debuta con me-tástasis cerebrales.Evolución: Se inció inmunoterapia con Pembrolizumab, el cual se mantubo hasta la presencia de un efecto secundario atribuido al pembrolizumab, cumpliendo 30meses de supervivencia hasta el cierre de esta observación no se reportó la muerte del paciente.Conclusiones:En el presente reporte, la determinación del biomarcador histológico PDL1 po-sitivo en cáncer de pulmón ayudo a prescribir un tratamiento con inmunoterpia dirigida, lo que demostró aumentar la supervivencia más allá que el tratamiento convencional con quimiote-rapia


Introduction: Immunotherapy with pembrolizumab has improved the prognosis of metastatic lung cancer. A specific patient's extended survival and evolution is presented in the present case.Clinical case: 66-year-old man, smoker. Diagnosed with a lung mass in the left lower lobe measuring 9 x 8 cm, with supra and infratentorial intra-axial metastases.Diagnostic workshop: To establisha stage IVc lung neoplasm, 80% of the lung mass sample was confirmed to be positive for PDL1.Evolution: Immunotherapy was started with Pembrolizumab, which was maintained until the presence of a side effect attributed to pembrolizumab, completing 30 months of survival until the closure of this observation, the patient's death was not reported.Conclusions: In the present report, the determination of the positive histological biomarker PDL1 in lung cancer helped prescribe treatment with targeted immunotherapy, which was shown to increase survival beyond conventional treatment with chemotherapy


Assuntos
Humanos , Masculino , Idoso , Imunoterapia , Neoplasias Pulmonares , Pneumopatias
12.
Oncología (Guayaquil) ; 32(3): 266-272, 2 de diciembre del 2022.
Artigo em Espanhol | LILACS | ID: biblio-1411126

RESUMO

La comunicación de malas noticias, si bien supone un momento de importante vulnerabilidad para el paciente y sus allegados, es un acto necesario para una atención de calidad. Se trata de una habilidad transversal que, sin embargo, suele carecer de una formación específica en las facultades de Medici-na. Existen numerosos protocolos que establecen las bases de una comunicación eficiente. No obs-tante, lo que marca la diferencia en términos de humanidad es el toque personal que cada médico ofrece. En este artículo ofrecemos una reflexión sobre la visión predominante en el Servicio de Onco-logía Médica de Fuenlabrada del proceso de comunicación de malas noticias. Exponemos conceptos metafísicos, psicológicos y sociales sobre los cuales impera la necesidad de reflexionar para, desde una compresión profunda de la dificultad que la comunicación de malas noticias entraña, ser capa-ces de mejorar. Así mismo, sugerimos elementos fácilmente incorporables a la práctica clínica diaria.


Although the communication of bad news is a moment of great vulnerability for the patient and his or her relatives, it is necessary for quality care. However, it is a cross-cutting skill that often needs more specific training in medical schools. Numerous protocols lay the groundwork for efficient communication. However, each physician's personal touch makes a difference in terms of humanity. In this article, we reflect on the predominant vision of communicating bad news in the Medical On-cology Service of Fuenlabrada. We expose metaphysical, psychological, and social concepts on which there is a need to reflect to be able to improve from a deep understanding of the difficulty that the communication of bad news entails. Finally, we suggest elements that can be easily incorporated into daily clinical practice.


Assuntos
Humanos , Cuidados Paliativos , Neoplasias , Mortalidade , Comunicação , Comunicação Interdisciplinar , Comunicação em Saúde
13.
Cir. gen ; 19(1): 37-40, ene.-mar. 1997. ilus
Artigo em Espanhol | LILACS | ID: lil-226837

RESUMO

Objetivo. La Pancreatitis Aguda (PA) tiene múltiples etiologías, una de las más raras es el hiperparatiroidismo primario (HPP). La incidencia de la PA en pacientes con HPP varía desde el 7 al 12 por ciento. En nuestra institución este caso representa el único de PA e HPP de 216 de PA vistos en los últimos 3 años. Caso clínico. Paciente masculino de 20 años de edad, sin antecedentes que sugieran HPP, fue visto en el servicio con cuadro de PA severa, con 3 criterios de Ranson y Apache II de 6 a su ingreso, así como calcio sérico de 12.99 mg/dl. En la pancreatografía dinámica se observó necrosis pancreática; fue manejado conservadoramente y se le estudió para descartar HPP. Se identificó un adenoma paratiroideo en la centellografía por lo que a los 20 días de su ingreso fue intervenido, extirpando un adenoma de 2.5 cm. Cinco días después presentó fiebre de 39ºC, por lo que se realizó punción de la necrosis. En la tinción de Gram se identificaron cocos gram positivo, por lo que se realizó necosectomía, lavado de cavidad y empaquetamiento; tres días después se intervino nuevamente y se efectuó nuevamente necrosectomía, lavado y cierre de cavidad, se dejó drenaje con sonda de tres lúmenes para irrigación continua en el post-operatorio. Fue dado de alta 42 días después de su ingreso y un año más tarde se encuentra con calcio, glucemia y función pancreática exocrina normal


Assuntos
Humanos , Masculino , Adulto , Adenoma/diagnóstico , Adenoma/cirurgia , Pancreatopatias/cirurgia , Pancreatopatias/diagnóstico , Pancreatopatias/etiologia , Glândulas Paratireoides/patologia , Hipercalcemia/etiologia , Hiperparatireoidismo/complicações , Hiperparatireoidismo/diagnóstico , Hiperparatireoidismo/etiologia , Necrose/diagnóstico , Necrose/etiologia , Necrose/cirurgia , Tomografia
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