Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
BMC Health Serv Res ; 21(1): 12, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33397363

RESUMEN

BACKGROUND: Optimizing access to recanalization therapies in acute ischemic stroke patients is crucial. Our aim was to measure the short and long term effectiveness, at the acute phase and 1 year after stroke, of four sets of actions implemented in the Rhône County. METHODS: The four multilevel actions were 1) increase in stroke units bed capacity and development of endovascular therapy; 2) improvement in knowledge and skills of healthcare providers involved in acute stroke management using a bottom-up approach; 3) development and implementation of new organizations (transportation routes, pre-notification, coordination by the emergency call center physician dispatcher); and 4) launch of regional public awareness campaigns in addition to national campaigns. A before-and-after study was conducted with two identical population-based cohort studies in 2006-7 and 2015-16 in all adult ischemic stroke patients admitted to any emergency department or stroke unit of the Rhône County. The primary outcome criterion was in-hospital management times, and the main secondary outcome criteria were access to reperfusion therapy (either intravenous thrombolysis or endovascular treatment) and pre-hospital management times in the short term, and 12-month prognosis measured by the modified Rankin Scale (mRS) in the long term. RESULTS: Between 2015-16 and 2006-7 periods ischemic stroke patients increased from 696 to 717, access to reperfusion therapy increased from 9 to 23% (p < 0.0001), calls to emergency call-center from 40 to 68% (p < 0.0001), first admission in stroke unit from 8 to 30% (p < 0.0001), and MRI within 24 h from 18 to 42% (p < 0.0001). Onset-to-reperfusion time significantly decreased from 3h16mn [2 h54-4 h05] to 2h35mn [2 h05-3 h19] (p < 0.0001), mainly related to a decrease in delay from admission to imaging. A significant decrease of disability was observed, as patients with mild disability (mRS [0-2]) at 12 months increased from 48 to 61% (p < 0.0001). Pre-hospital times, however, did not change significantly. CONCLUSIONS: We observed significant improvement in access to reperfusion therapy, mainly through a strong decrease of in-hospital management times, and in 12-month disability after the implementation of four sets of actions between 2006 and 2016 in the Rhône County. Reducing pre-hospital times remains a challenge.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Adulto , Isquemia Encefálica/terapia , Humanos , Estudios Prospectivos , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Resultado del Tratamiento
2.
Ann Pharm Fr ; 79(3): 286-290, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33098873

RESUMEN

Drug packaging contributes to the harm-benefit balance of a treatment. Poorly designed packaging can lead to drug misuse with serious consequences. We report a potassium double dose medication error concerning an oral solution. It was triggered by a packaging flaw related to the dosage indicated on the box, expressed for both potassium salt and elemental potassium. Standardizing the units used on packaging and for prescriptions, by using millimoles, could be a solution to avoid this type of medication error.


Asunto(s)
Sobredosis de Droga , Embalaje de Medicamentos , Humanos , Errores de Medicación , Potasio
3.
Khirurgiia (Mosk) ; (11. Vyp. 2): 36-40, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-28008901

RESUMEN

Surgical indications for thymectomy include thymus tumour of different genesis as well as myasthenia. Minimally invasive methods such as thorascopy and robot-assisted thymectomy have been widely used lately as well as standard surgical methods namely sternotomy and thoracotomy. Regardless the type of access in myasthenia patients specific crisis conditions of respiratory failure can appear in postoperative period that usually requires mechanical ventilation. This study was aimed to estimate the efficacy of pre- and postoperative plasmapheresis in prevention of specific myasthenia-associated complications.


Asunto(s)
Plasmaféresis , Complicaciones Posoperatorias/prevención & control , Timectomía/efectos adversos , Hiperplasia del Timo/cirugía , Humanos , Miastenia Gravis , Cirugía Torácica Asistida por Video , Resultado del Tratamiento
4.
Khirurgiia (Mosk) ; (2): 37-43, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26031818

RESUMEN

Esophagectomy with simultaneous plasty in patient with esophageal cancer is still associated with a high incidence of postoperative complications and long-stay patient in the clinic. The purpose of our report is to inform the use of the program of accelerated rehabilitation after esophagectomy in a prospective study of 13 patients during the period from 2010 to 2011 year and the role of the anesthesiologist in its implementation. Methods aimed at the preoperative examination, minimally invasive surgery, thoracic epidural anesthesia/analgesia with local anesthetics as a component of anesthesia and postoperative analgesia, early extubation and mobilization of the patient with the implementation of breathing exercises, early enteral feeding, and the planned short postoperative stay in resuscitation and hospital were used. Postoperative complications were observed in 3 (23/1%) patients: one patient (7/7%) had right-side pneumonia, two patients (15/4%) had right-side pneumothorax requiring emergency re drainage. The average intensive care stay was 2 (1-4) days, postoperative hospital stay--9 (7-12) days. Further monitoring of the patients did not show any long-term complications. The results confirm that it is possible to optimize the healing perioperative process in patients after esophagectomy with simultaneous plasty by using of accelerated rehabilitation program without the risk of increasing the frequency of postoperative complications. it will provide the reduction of length of hospital stay. In view of multifaceted and controversial issue the following researches in this direction are necessary.


Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagectomía/rehabilitación , Esofagoplastia/rehabilitación , Cuidados Posoperatorios/métodos , Complicaciones Posoperatorias/rehabilitación , Adulto , Anciano , Neoplasias Esofágicas/rehabilitación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
Biochem Soc Trans ; 42(6): 1519-23, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25399563

RESUMEN

The successful treatment of cancer in a disseminated stage using chemotherapy is limited by the occurrence of drug resistance, often mediated by anti-apoptotic mechanisms. Thus the challenge is to pinpoint the underlying key factors and to develop therapies for their direct targeting. Protein kinase C (PKC) enzymes are promising candidates, as some PKCs were shown to be involved in regulation of apoptosis. Our studies and others have shown that PKCη is an anti-apoptotic kinase, able to confer protection on tumour cells against stress and chemotherapy. We have demonstrated that PKCη shuttles between the cytoplasm and the nucleus and that upon DNA damage is tethered at the nuclear membrane. The C1b domain mediates translocation of PKCη to the nuclear envelope and, similar to the full-length protein, could also confer protection against cell death. Furthermore, its localization in cell and nuclear membranes in breast cancer biopsies of neoadjuvant-treated breast cancer patients was an indicator for poor survival and a predictor for the effectiveness of treatment. PKCη is also a novel biomarker for poor prognosis in non-small-cell lung cancer (NSCLC). Thus PKCη presents a potential target for therapy where inhibition of its activity and/or translocation to membranes could interfere with the resistance to chemotherapy.


Asunto(s)
Apoptosis , Neoplasias de la Mama/enzimología , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Neoplasias Pulmonares/enzimología , Proteína Quinasa C/metabolismo , Neoplasias de la Mama/patología , Carcinoma de Pulmón de Células no Pequeñas/patología , Daño del ADN , Femenino , Humanos , Neoplasias Pulmonares/patología , Pronóstico
6.
Nat Commun ; 15(1): 2003, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443359

RESUMEN

Airborne transmission of SARS-CoV-2 aerosol remains contentious. Importantly, whether cough or breath-generated bioaerosols can harbor viable and replicating virus remains largely unclarified. We performed size-fractionated aerosol sampling (Andersen cascade impactor) and evaluated viral culturability in human cell lines (infectiousness), viral genetics, and host immunity in ambulatory participants with COVID-19. Sixty-one percent (27/44) and 50% (22/44) of participants emitted variant-specific culture-positive aerosols <10µm and <5µm, respectively, for up to 9 days after symptom onset. Aerosol culturability is significantly associated with lower neutralizing antibody titers, and suppression of transcriptomic pathways related to innate immunity and the humoral response. A nasopharyngeal Ct <17 rules-in ~40% of aerosol culture-positives and identifies those who are probably highly infectious. A parsimonious three transcript blood-based biosignature is highly predictive of infectious aerosol generation (PPV > 95%). There is considerable heterogeneity in potential infectiousness i.e., only 29% of participants were probably highly infectious (produced culture-positive aerosols <5µm at ~6 days after symptom onset). These data, which comprehensively confirm variant-specific culturable SARS-CoV-2 in aerosol, inform the targeting of transmission-related interventions and public health containment strategies emphasizing improved ventilation.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Cinética , Aerosoles y Gotitas Respiratorias
7.
Exp Cell Res ; 318(7): 789-99, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22305966

RESUMEN

The PI3K-AKT pathway is frequently activated in human cancers, including breast cancer, and its activation appears to be critical for tumor maintenance. Some malignant cells are dependent on activated AKT for their survival; tumors exhibiting elevated AKT activity show sensitivity to its inhibition, providing an Achilles heel for their treatment. Here we show that the PKCη isoform is a negative regulator of the AKT signaling pathway. The IGF-I induced phosphorylation on Ser473 of AKT was inhibited by the PKCη-induced expression in MCF-7 breast adenocarcinoma cancer cells. This was further confirmed in shRNA PKCη-knocked-down MCF-7 cells, demonstrating elevated phosphorylation on AKT Ser473. While PKCη exhibited negative regulation on AKT phosphorylation it did not alter the IGF-I induced ERK phosphorylation. However, it enhanced ERK phosphorylation when stimulated by PDGF. Moreover, its effects on IGF-I/AKT and PDGF/ERK pathways were in correlation with cell proliferation. We further show that both PKCη and IGF-I confer protection against UV-induced apoptosis and cell death having additive effects. Although the protective effect of IGF-I involved activation of AKT, it was not affected by PKCη expression, suggesting that PKCη acts through a different route to increase cell survival. Hence, our studies show that PKCη provides negative control on AKT pathway leading to reduced cell proliferation, and further suggest that its presence/absence in breast cancer cells will affect cell death, which could be of therapeutic value.


Asunto(s)
Adenocarcinoma/metabolismo , Neoplasias de la Mama/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Proteína Oncogénica v-akt/metabolismo , Proteína Quinasa C/metabolismo , Adenocarcinoma/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Isoenzimas/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteína Quinasa C/genética , ARN Interferente Pequeño/metabolismo , Serina/metabolismo , Transducción de Señal/efectos de los fármacos , Rayos Ultravioleta
8.
Phys Rev Lett ; 107(15): 158701, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-22107325

RESUMEN

Density functional theory (DFT) calculations are performed for the adsorption energy of hydrogen and oxygen on graphene decorated with a wide set of metals (Li, Na, K, Al, Ti, V, Ni, Cu, Pd, Pt). It is found that oxygen interferes with hydrogen adsorption by either blocking the adsorption site or by the irreversible oxidation of the metal decoration. The most promising decorations are Ni, Pd, and Pt due to a reasonable relationship of adsorption energies which minimize the oxygen interference. The DFT results are used to parametrize a statistical mechanical model which allows evaluation of the effect of partial pressures in the gas phase during storage. According to this model, even in the most promising case, it is necessary to reduce the oxygen partial pressure close to ultrahigh vacuum conditions to allow hydrogen storage.

9.
Rev Med Interne ; 39(3): 148-154, 2018 Mar.
Artículo en Francés | MEDLINE | ID: mdl-29415816

RESUMEN

INTRODUCTION: The French Agency for Health Safety of Products published recommendations of good practices (RGP) for the treatment of venous thromboembolic disease in 2009. Four of these recommendations apply to the initial management of the disease, with the objective of this study is to determine whether the development and diffusion of the four RGP has had an impact on the practice. METHODS: A retrospective before/after study comparing 132 patients treated in emergency department of the Civil Hospices of Lyon for pulmonary embolism (PE) and/or deep venous thrombosis (DVT) in 2008-2009 ("before") and 153 patients in 2010-2011 ("after"). RESULTS: In the "before" period, 70 patients were treated for DVT and 62 patients for PE. In the "after" period, 50 patients were treated for DVT and 103 patients for PE. The compliance rate was not significantly different for the two periods for each RGP except for the indication of low molecular weight Heparin (LMWH) or fondaparinux in the absence of severe renal failure (21% "before" vs. 45% "after"; P=0.02) for patients with PE. Management for the four recommendations was conform for 5.6% of eligible patients in the "before" period and for 3.7% for the "after" period. CONCLUSION: Our study shows that globally there is no impact of RGP. The reasons appear multiple with first, the mere dissemination and the absence of implementation of these guidelines.


Asunto(s)
Servicio de Urgencia en Hospital , Guías de Práctica Clínica como Asunto , Tromboembolia Venosa/terapia , Anciano , Servicios Médicos de Urgencia/métodos , Servicios Médicos de Urgencia/normas , Servicios Médicos de Urgencia/estadística & datos numéricos , Servicio de Urgencia en Hospital/normas , Femenino , Francia/epidemiología , Adhesión a Directriz/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Seguridad del Paciente/normas , Administración en Salud Pública/normas , Estudios Retrospectivos , Sociedades Médicas , Tromboembolia Venosa/epidemiología
10.
Mol Cell Biol ; 21(5): 1552-64, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11238892

RESUMEN

The cellular function of p53 is complex. It is well known that p53 plays a key role in cellular response to DNA damage. Moreover, p53 was implicated in cellular senescence, and it was demonstrated that p53 undergoes modification in senescent cells. However, it is not known how these modifications affect the ability of senescent cells to respond to DNA damage. To address this question, we studied the responses of cultured young and old normal diploid human fibroblasts to a variety of genotoxic stresses. Young fibroblasts were able to undergo p53-dependent and p53-independent apoptosis. In contrast, senescent fibroblasts were unable to undergo p53-dependent apoptosis, whereas p53-independent apoptosis was only slightly reduced. Interestingly, instead of undergoing p53-dependent apoptosis, senescent fibroblasts underwent necrosis. Furthermore, we found that old cells were unable to stabilize p53 in response to DNA damage. Exogenous expression or stabilization of p53 with proteasome inhibitors in old fibroblasts restored their ability to undergo apoptosis. Our results suggest that stabilization of p53 in response to DNA damage is impaired in old fibroblasts, resulting in induction of necrosis. The role of this phenomenon in normal aging and anticancer therapy is discussed.


Asunto(s)
Senescencia Celular , Daño del ADN , Fibroblastos/metabolismo , Fibroblastos/patología , Proteína p53 Supresora de Tumor/metabolismo , Naranja de Acridina/farmacología , Antibióticos Antineoplásicos/farmacología , Antineoplásicos/farmacología , Apoptosis , Western Blotting , Separación Celular , Células Cultivadas , Cisplatino/farmacología , Cisteína Endopeptidasas , Dactinomicina/farmacología , Electroforesis en Gel de Poliacrilamida , Etopósido/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/efectos de la radiación , Citometría de Flujo , Colorantes Fluorescentes/farmacología , Humanos , Modelos Biológicos , Complejos Multienzimáticos/antagonistas & inhibidores , Necrosis , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Complejo de la Endopetidasa Proteasomal , Factores de Tiempo , Transfección , Proteína p53 Supresora de Tumor/biosíntesis , Rayos Ultravioleta
11.
Cancer Res ; 60(24): 6788-93, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11156366

RESUMEN

The p53 guardian of the genome is inactivated in the majority of cancers, mostly through missense mutations that cause single residue changes in the DNA binding core domain of the protein. Not only do such mutations result in the abrogation of wild-type p53 activity, but the expressed p53 mutant proteins also tend to gain oncogenic functions, such as interference with wild-type p53-independent apoptosis. Because p53 mutants are highly expressed in cancer cells and not in normal cells, their reactivation to wild-type p53 function may eliminate the cancer by apoptosis or another p53-dependent mechanism. Several studies that embarked on this quest for reactivation have succeeded in restoring wildtype p53 activity to several p53 mutants. However, mutants with more extensive structural changes in the DNA binding core domain may be refractory to reactivation to the wild-type p53 phenotype. Therefore, understanding the structure and functions of oncogenic p53 mutants may lead to more potent reactivation modalities or to the ability to eliminate mutant p53 gain of function.


Asunto(s)
Genes p53 , Mutación , Neoplasias/genética , Animales , Apoptosis , ADN/metabolismo , Humanos , Ratones , Modelos Biológicos , Mutación Missense , Fenotipo , Polimorfismo Genético , Estructura Terciaria de Proteína , Activación Transcripcional , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/fisiología
12.
Oncogene ; 20(35): 4891-8, 2001 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-11521201

RESUMEN

The ability to suppress wild type p53-independent apoptosis may play an important role in the oncogenicity of p53 mutant proteins. However, structural elements necessary for this activity are unknown. Furthermore, it is unclear whether this mutant p53 mediated inhibition is specific to the apoptotic pathway or a more general suppression of the cellular response to stress. We observed that an unmodified C-terminus was required for the suppression of apoptosis by the p53 135(Ala to Val) oncogenic p53 mutant. It was also required for the novel activity of G2 arrest suppression, the predominant response at low levels of genotoxic stress. These observations are consistent with a model whereby mutant p53 suppressive activity is not specific to the apoptotic pathway, but rather increases the threshold of genotoxic stress needed for a DNA damage response to occur. Furthermore, these observations indicate that it may be possible to selectively kill mutant p53 expressing cells based on the lower sensitivity of their growth arrest response.


Asunto(s)
Apoptosis , Mutación , Proteína p53 Supresora de Tumor/fisiología , Animales , Apoptosis/efectos de los fármacos , División Celular , Cisplatino/farmacología , Daño del ADN , Etopósido/farmacología , Fase G2 , Humanos , Ratones , Proteína p53 Supresora de Tumor/química
13.
Maturitas ; 8(4): 353-8, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3033446

RESUMEN

Cytosolic and nuclear progesterone receptors (RPC, RPN) were measured in post-menopausal endometria, using [3H]R5020 as the radioligand, and the findings compared with those in pre-menopausal endometria. Total RP levels (RPC + RPN) in post-menopausal endometria were low, i.e. less than 2000 fmol/mg DNA. A 7-11 day course of Premarin (conjugated equine oestrogen) treatment in post-menopausal subjects resulted in RP levels in 11818 +/- 3008 fmol/mg DNA, which were higher than those in proliferative, mid-cycle and Premarin-primed pre-menopausal endometria. Progesterone injection 1-3 h before tissue collection resulted in a change in the distribution of the RP in both premenopausal and post-menopausal Premarin-primed endometria and pre-menopausal proliferative and mid-cycle endometria. Following the progesterone injection RPN levels increased to 57 +/- 9% of the total as compared with 23 +/- 8% in endometrial samples from women who received no progesterone.


Asunto(s)
Endometrio/análisis , Estrógenos Conjugados (USP)/farmacología , Menopausia , Progesterona/farmacología , Receptores de Progesterona/análisis , Adulto , Núcleo Celular/análisis , Citosol/análisis , Endometrio/efectos de los fármacos , Femenino , Humanos , Persona de Mediana Edad
14.
Am Surg ; 61(11): 964-7, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7486428

RESUMEN

Postoperative outcome and severity of acute cholecystitis in 32 diabetic patients (DM) who underwent urgent cholecystectomy were compared on a case-control basis with 32 nondiabetic age/sex matched controls. There was no difference in incidence of renal and lung diseases or duration of acute symptoms before surgery. Cardiovascular diseases were more often seen in the diabetic group (16/32 in DM, 7/32 in controls, P = 0.03). Bactobilia was more often in diabetics (19 in DM, 11 in controls, p = 0.07). Postoperatively, there was a trend toward higher incidence in overall complication rate. Infectious complications (wound and respiratory infections, hepatic abscess) were higher in DM, although the difference was not statistically significant. One patient in DM group died as a result of multiorgan failure. There was no difference in total and postoperative hospital stay. The severity of acute cholecystitis was greater in diabetics (26 patients with moderate-to-severe cholecystitis in DM group, 18 in control group, P = 0.05). The study indicates that although pathological findings were more severe in DM group, the postoperative course is comparable in diabetics as compared to age and sex matched nondiabetic controls. Our findings justify reconsideration of prophylactic cholecystectomy in asymptomatic diabetic patients.


Asunto(s)
Colecistitis/complicaciones , Complicaciones de la Diabetes , Complicaciones Posoperatorias/epidemiología , Enfermedad Aguda , Enfermedades Cardiovasculares/complicaciones , Estudios de Casos y Controles , Colecistectomía , Colecistitis/epidemiología , Colecistitis/cirugía , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
17.
Science ; 322(5907): 1511-6, 2008 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-19023046

RESUMEN

Why do seemingly identical cells respond differently to a drug? To address this, we studied the dynamics and variability of the protein response of human cancer cells to a chemotherapy drug, camptothecin. We present a dynamic-proteomics approach that measures the levels and locations of nearly 1000 different endogenously tagged proteins in individual living cells at high temporal resolution. All cells show rapid translocation of proteins specific to the drug mechanism, including the drug target (topoisomerase-1), and slower, wide-ranging temporal waves of protein degradation and accumulation. However, the cells differ in the behavior of a subset of proteins. We identify proteins whose dynamics differ widely between cells, in a way that corresponds to the outcomes-cell death or survival. This opens the way to understanding molecular responses to drugs in individual cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Camptotecina/farmacología , ADN-Topoisomerasas de Tipo I/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas/metabolismo , Proteoma/metabolismo , Muerte Celular , División Celular/efectos de los fármacos , Línea Celular Tumoral , Nucléolo Celular/efectos de los fármacos , Nucléolo Celular/metabolismo , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , ARN Helicasas DEAD-box/metabolismo , Daño del ADN , Inhibidores Enzimáticos/farmacología , Fluorescencia , Humanos , Proteínas Luminiscentes/metabolismo , Redes y Vías Metabólicas , Estrés Oxidativo , Proteómica , Proteína de Replicación C/metabolismo , Inhibidores de Topoisomerasa I
18.
J Acoust Soc Am ; 101(3): 1585-99, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9069627

RESUMEN

This study investigated the effects of decreased audibility produced by high-pass noise masking on cortical event-related potentials (ERPs) N1, N2, and P3 to the speech sounds /ba/and/da/presented at 65 and 80 dB SPL. Normal-hearing subjects pressed a button in response to the deviant sound in an oddball paradigm. Broadband masking noise was presented at an intensity sufficient to completely mask the response to the 65-dB SPL speech sounds, and subsequently high-pass filtered at 4000, 2000, 1000, 500, and 250 Hz. With high-pass masking noise, pure-tone behavioral thresholds increased by an average of 38 dB at the high-pass cutoff and by 50 dB one octave above the cutoff frequency. Results show that as the cutoff frequency of the high-pass masker was lowered, ERP latencies to speech sounds increased and amplitudes decreased. The cutoff frequency where these changes first occurred and the rate of the change differed for N1 compared to N2, P3, and the behavioral measures. N1 showed gradual changes as the masker cutoff frequency was lowered. N2, P3, and behavioral measures showed marked changes below a masker cutoff of 2000 Hz. These results indicate that the decreased audibility resulting from the noise masking affects the various ERP components in a differential manner. N1 is related to the presence of audible stimulus energy, being present whether audible stimuli are discriminable or not. In contrast, N2 and P3 were absent when the stimuli were audible but not discriminable (i.e., when the second formant transitions were masked), reflecting stimulus discrimination. These data have implications regarding the effects of decreased audibility on cortical processing of speech sounds and for the study of cortical ERPs in populations with hearing impairment.


Asunto(s)
Corteza Auditiva/fisiología , Potenciales Evocados , Ruido/efectos adversos , Enmascaramiento Perceptual , Fonética , Acústica del Lenguaje , Adolescente , Adulto , Audiometría de Tonos Puros , Umbral Auditivo , Electroencefalografía , Femenino , Humanos , Masculino , Tiempo de Reacción
19.
Isr J Med Sci ; 23(12): 1198-204, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3440742

RESUMEN

Total estradiol and progesterone receptor levels and DNA concentrations were measured in endometria of four women with nonuniform postovulatory delayed maturation of the epithelium. All four women underwent curettage on Days 21 to 23 of their cycle. The results in these women were compared with results obtained from a control group of women with histologically normal cyclic endometrium. In three women with corpus luteum defect, total estradiol and progesterone receptor levels and DNA concentrations were in the range of midcycle or early secretory normal (control) endometria. In one patient with a normally functioning corpus luteum, the above parameters were similar to those found in the late secretory phase of controls. Summation of the results of the present study along with those previously reported in endometria of women, both with uniform and nonuniform delayed maturation, indicate the possibility of endometrial postacceptorial progesterone defect, which may either be secondary to corpus luteum defect or a result of primary endometrial defect.


Asunto(s)
ADN/metabolismo , Endometrio/metabolismo , Fase Luteínica , Receptores de Estradiol/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Endometrio/patología , Endometrio/fisiopatología , Epitelio/fisiopatología , Femenino , Humanos , Persona de Mediana Edad
20.
EMBO J ; 20(15): 4163-72, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11483519

RESUMEN

The present study examined whether the ability of mutant p53 to block apoptosis depended on its transcriptional activity. A core domain mutant p53 (143 Val to Ala), in which two N-terminal residues (22 and 23) essential for transactivation were also mutated (Leu to Glu and Trp to Ser, respectively), was examined. While p53 containing only the core mutation efficiently interfered with drug-induced apoptosis, further modification at the N-terminus abolished this blocking activity. Furthermore, expression of c-myc, a suggested target for core mutant p53 transactivation, was elevated in the core mutant p53-expressing cells, but was abolished in the presence of the transcription-deficient p53 core mutant. In addition, wild-type p53, mutated in the N-terminus (residues 22 and 23), was unable to induce apoptosis by itself. Nevertheless, it synergized with drugs in the induction of apoptosis. This suggests that the integrity of the N-terminus is essential for both the activity of wild-type p53 in apoptosis and for mutant p53-mediated block of drug-induced apoptosis. This supports the notion that core p53 mutants act via a gain of function mechanism.


Asunto(s)
Apoptosis , Transactivadores/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Alanina/genética , Amanitinas/farmacología , Línea Celular , Cisplatino/farmacología , Dactinomicina/farmacología , Doxorrubicina/farmacología , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Sustancias Intercalantes/farmacología , Mutagénesis Sitio-Dirigida , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Polimerasa II/antagonistas & inhibidores , Relación Estructura-Actividad , Transactivadores/genética , Proteína p53 Supresora de Tumor/genética , Valina/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA