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1.
Microbiol Spectr ; 9(1): e0014521, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34106579

RESUMO

Upon Kaposi's Sarcoma-associated herpesvirus (KSHV) lytic reactivation, rapid and widespread amplification of viral DNA (vDNA) triggers significant nuclear reorganization. As part of this striking shift in nuclear architecture, viral replication compartments are formed as sites of lytic vDNA production along with remarkable spatial remodeling and the relocalization of cellular and viral proteins. These viral replication compartments house several lytic gene products that coordinate viral gene expression, vDNA replication, and nucleocapsid assembly. The viral proteins and mechanisms that regulate this overhaul of the nuclear landscape during KSHV replication remain largely unknown. KSHV's ORF20 is a widely conserved lytic gene among all herpesviruses, suggesting it may have a fundamental contribution to the progression of herpesviral infection. Here, we utilized a promiscuous biotin ligase proximity labeling method to identify the proximal interactome of ORF20, which includes several replication-associated viral proteins, one of which is ORF59, the KSHV DNA processivity factor. Using coimmunoprecipitation and immunofluorescence assays, we confirmed the interaction between ORF20 and ORF59 and tracked the localization of both proteins to KSHV replication compartments. To further characterize the function of ORF20, we generated an ORF20-deficient KSHV and compared its replicative fitness to that of wild-type virus. Virion production was significantly diminished in the ORF20-deficient virus as observed by supernatant transfer assays. Additionally, we tied this defect in viable virion formation to a reduction in viral late gene expression. Lastly, we observed an overall reduction in vDNA replication in the ORF20-deficient virus, implying a key role for ORF20 in the regulation of lytic replication. Taken together, these results capture the essential role of KSHV ORF20 in progressing viral lytic infection by regulating vDNA replication alongside other crucial lytic proteins within KSHV replication compartments. IMPORTANCE Kaposi's Sarcoma-associated herpesvirus (KSHV) is a herpesvirus that induces lifelong infection, and as such, its lytic replication is carefully controlled to allow for efficient dissemination from its long-term reservoir and for the spread of the virus to new hosts. Viral DNA replication involves many host and viral proteins, coordinating both in time and space to successfully progress through the viral life cycle. Yet, this process is still not fully understood. We investigated the role of the poorly characterized viral protein ORF20, and through proximity labeling, we found that ORF20 interacts with ORF59 in replication compartments and affects DNA replication and subsequent steps of the late viral life cycle. Collectively, these results provide insights into the possible contribution of ORF20 to the complex lytic DNA replication process and suggest that this highly conserved protein may be an important modulator of this key viral mechanism.


Assuntos
Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/metabolismo , Proteínas Virais/metabolismo , Ativação Viral , Replicação Viral , Replicação do DNA , Regulação Viral da Expressão Gênica , Herpesvirus Humano 8/genética , Humanos , Ligação Proteica , Proteínas Virais/genética
2.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 61(3): 139-145, mayo-jun. 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-180204

RESUMO

Introducción: la cumplimentación de registros sobre la implantación de prótesis permite obtener una gran cantidad de datos y extraer conclusiones que redundan en la mejora de la utilización de las mismas. Suecia fue el primer país en implantar un sistema de registro de artroplastias en 1979. Cataluña lo viene haciendo desde el año 2005. El objetivo de nuestro trabajo es analizar la evidencia que respalda a las prótesis implantadas en artroplastias totales de cadera primarias en Cataluña en los últimos 9 años sobre la base del Registro de Artroplastias de Cataluña (RACat). Material y métodos: se realizó una revisión en la literatura de las prótesis (cotilos/vástagos) registrados en el RACat entre los años 2005-2013 en las siguientes bases datos: Orthopaedic Data Evaluation Panel (ODEP), Tripdatabase, Pubmed, Google académico. Se excluyeron aquellas prótesis implantadas en número inferior a 10 unidades (182 cotilos correspondientes a 49 modelos/228 vástagos correspondientes a 63 modelos). Resultados: de los 18.816 cotilos implantados, se analizaron 18.634 (el 99%), correspondientes a 74 modelos diferentes. En 18 modelos (2.527 cotilos) no se encontraron evidencias clínicas que respalden su uso. De los 19.595 vástagos implantados se analizaron 19.367 (el 98,84%), correspondientes a 75 modelos diferentes. En 16 modelos (1.845 vástagos) no se encontraron evidencias clínicas que respalden su uso. En los 56 modelos de cotilos (16.107) y los 59 modelos de vástagos (17.522) restantes las evidencias variaron en función del número de pacientes y los años de seguimiento, predominando los estudios con nivel de evidencia iv. Conclusiones: existe un número significativo de prótesis implantadas evaluadas (13,56% cotilos/9,5% vástagos) en los que no se han encontrado evidencias clínicas. Cabe destacar el alto número de modelos (49 tipos para cotilos/63 tipos para vástagos) con una implantación inferior a 10 unidades que corresponden únicamente al 1% del total. La implantación de registros de artroplastias se revela como una herramienta extremadamente útil al permitirnos analizar y extraer conclusiones para la evaluación y el seguimiento poscomercialización


Introduction: the implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). Material and methods: a review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. Results: a total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. Conclusions: there was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period


Assuntos
Humanos , Artroplastia de Quadril/instrumentação , Prótese de Quadril/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Medicina Baseada em Evidências , Sistema de Registros , Espanha
3.
Rev Esp Cir Ortop Traumatol ; 61(3): 139-145, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27916532

RESUMO

INTRODUCTION: The implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). MATERIAL AND METHODS: A review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. RESULTS: A total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. CONCLUSIONS: There was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period.


Assuntos
Artroplastia de Quadril/instrumentação , Prótese de Quadril/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Medicina Baseada em Evidências , Humanos , Sistema de Registros , Espanha
4.
J Environ Radioact ; 151 Pt 3: 579-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26344369

RESUMO

Soil and sediment samples from the Sydney basin were measured to ascertain fallout radionuclide activity concentrations and atom ratios. Caesium-137 ((137)Cs) was measured using gamma spectroscopy, and plutonium isotopes ((239)Pu and (240)Pu) were quantified using accelerator mass spectrometry (AMS). Fallout radionuclide activity concentrations were variable ranging from 0.6 to 26.1 Bq/kg for (137)Cs and 0.02-0.52 Bq/kg for (239+240)Pu. Radionuclides in creek sediment samples were an order of magnitude lower than in soils. (137)Cs and (239+240)Pu activity concentration in soils were well correlated (r(2) = 0.80) although some deviation was observed in samples collected at higher elevations. Soil ratios of (137)Cs/(239+240)Pu (decay corrected to 1/1/2014) ranged from 11.5 to 52.1 (average = 37.0 ± 12.4) and showed more variability than previous studies. (240)Pu/(239)Pu atom ratios ranged from 0.117 to 0.165 with an average of 0.146 (±0.013) and an error weighted mean of 0.138 (±0.001). These ratios are lower than a previously reported ratio for Sydney, and lower than the global average. However, these ratios are similar to those reported for other sites within Australia that are located away from former weapons testing sites and indicate that atom ratio measurements from other parts of the world are unlikely to be applicable to the Australian context.


Assuntos
Radioisótopos de Césio/análise , Plutônio/análise , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Sedimentos Geológicos/análise , Espectrometria de Massas , New South Wales
6.
J Environ Radioact ; 106: 1-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22304994

RESUMO

A Compton suppressed high-purity germanium (HPGe) detector is well suited to the analysis of low levels of radioactivity in environmental samples. The difference in geometry, density and composition of environmental calibration standards (e.g. soil) can contribute to excessive experimental uncertainty to the measured efficiency curve. Furthermore multiple detectors, like those used in a Compton suppressed system, can add complexities to the calibration process. Monte Carlo simulations can be a powerful complement in calibrating these types of detector systems, provided enough physical information on the system is known. A full detector model using the Geant4 simulation toolkit is presented and the system is modelled in both the suppressed and unsuppressed mode of operation. The full energy peak efficiencies of radionuclides from a standard source sample is calculated and compared to experimental measurements. The experimental results agree relatively well with the simulated values (within ∼5 - 20%). The simulations show that coincidence losses in the Compton suppression system can cause radionuclide specific effects on the detector efficiency, especially in the Compton suppressed mode of the detector. Additionally since low energy photons are more sensitive to small inaccuracies in the computational detector model than high energy photons, large discrepancies may occur at energies lower than ∼100 keV.


Assuntos
Monitoramento de Radiação/instrumentação , Radioisótopos/análise , Simulação por Computador , Germânio , Método de Monte Carlo , Monitoramento de Radiação/métodos , Espectrometria gama
7.
Auris Nasus Larynx ; 37(5): 648-50, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20417042

RESUMO

Human papilloma virus infection is thought to play a role in laryngeal carcinogenesis; the variable association reported in literature may be due to wide range of HPV genotypes. We report the case of a 51-year-old man affected by laryngeal squamous cell carcinoma; analysis of DNA extracted by cancer cells by an innovative molecular virology assay (INNO-LiPA HPV Genotyping Extra) showed the presence of two high-risk HPV genotypes, HPV-73 and -82. Immunohistochemical examination confirmed positivity for both capsid protein and viral oncogenic protein E7. Such association has never been reported in literature so far, and a brief discussion on the importance of assessing HPV status in laryngeal cancer is provided.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias Laríngeas/virologia , Papillomaviridae/classificação , Infecções por Papillomavirus/virologia , Biópsia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Sondas de DNA de HPV , Genótipo , Humanos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Laringectomia , Laringe/patologia , Laringe/virologia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Estadiamento de Neoplasias , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/cirurgia , Tomografia Computadorizada por Raios X
8.
Gerokomos (Madr., Ed. impr.) ; 18(3): 150-154, sept. 2007. ilus, tab
Artigo em Es | IBECS | ID: ibc-66636

RESUMO

La hipergranulación es un problema ocasional, pero a la vez no infrecuente,con el que se enfrentan muchos clínicos responsables del tratamientode heridas en su práctica diaria. Este fenómeno ocurre en unamplio abanico de heridas que incluyen las incisiones y heridas posquirúrgicas,los estomas (gastrostomías, traqueostomías, etc.) y las heridascrónicas.El objetivo del presente artículo es cuantificar y analizar la evidencia generadaen torno al tema de la hipergranulación en las heridas crónicas, mediantela búsqueda bibliográfica en diversas bases de datos.Tras el análisis y revisión de los diferentes documentos recuperados se evidencia,tanto cuantitativa como cualitativamente hablando, una escasezimportante de investigación en torno a la hipergranulación en heridas crónicas.Esto hace que el problema no se halle lo suficientemente explicado yque no existan evidencias sólidas que justifiquen el uso de un tratamientosobre otro


Hypergranulation is an occasional but no infrequent problem, which many clinicians face in their daily practice. This phenomenon occurs in a variety of wounds that includes post-surgical incisions and wounds, stomas (gastrostomies, tracheotomies.) and chronic wounds.The objective of the present article is to quantify and to analyze the evidence generated around the topic of the hypergranulation in chronic wounds, through the bibliographical search in diverse data bases.After the analysis and revision of the different recovered documents it is demonstrated, both in terms of quantity and quality, an important shortage of investigation around the hypergranulation in chronic wounds. Therefore, the problem is not sufficiently explained and solid evidences do not exist to justify the use of a treatment over another one


Assuntos
Humanos , Ferimentos e Lesões/patologia , Tecido de Granulação/patologia , Deiscência da Ferida Operatória/patologia , Doença Crônica
9.
Mol Reprod Dev ; 58(4): 444-50, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11241782

RESUMO

To determine whether oogonial proliferation and oocyte recruitment are under control of hypophyseal and/or ovarian factors, we carried out a series of investigations using Podarcis sicula, a lizard inhabiting the temperate lowlands of Europe in which oocyte recruitment occurs throughout the year, as animal model. Germinal beds containing oogonia and oocytes in prefollicular stages were cocultured with different ovarian compartments in presence/absence of FSH, and the effects of different treatments were evaluated by counting the number of prelepto-leptotene oocytes. Results revealed that oocyte recruitment from the pool of oogonia is under the control of a factor released by follicle cells while FSH has an indirect effect on modulating oogonial proliferation. SDS-PAGE analyses carried out on media conditioned by follicles suggest that the factor involved in the control of oocyte recruitment may be a small protein (about 21 kDa) and that its release is dependent on the period of the ovarian cycle but apparently not on the circulating levels of FSH.


Assuntos
Fatores Biológicos/metabolismo , Oócitos/citologia , Oogênese/fisiologia , Folículo Ovariano/metabolismo , Animais , Fatores Biológicos/isolamento & purificação , Fatores Biológicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Demecolcina/farmacologia , Difusão , Eletroforese em Gel de Poliacrilamida , Feminino , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/fisiologia , Células da Granulosa/metabolismo , Lagartos , Meiose , Peso Molecular , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Folículo Ovariano/citologia , Células Tecais/metabolismo
10.
Biochem Biophys Res Commun ; 274(2): 461-6, 2000 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10913360

RESUMO

It was previously shown that rhodanese, inactivated with hydrogen peroxide, could only be reactivated in the presence of a reductant or the substrate thiosulfate if these reagents were added soon after inactivation and if the oxidant was removed. Here, we report on the facilitated reactivation (75%) of hydrogen peroxide-inactivated rhodanese by the chaperone alpha-crystallin. Reactivation by the chaperone still required a reductant and thiosulfate. Without alpha-crystallin, but in the presence of the reductant and thiosulfate, the inactivated enzyme regained about 39% of its original activity. The alpha-crystallin-assisted reactivation of hydrogen peroxide-inactivated rhodanese was independent of ATP. Further, we found, that alpha-crystallin interacted transiently, but could not form a stable complex with hydrogen peroxide-inactivated rhodanese. Unlike in prior studies that involved denaturation of rhodanese through chemical or thermal means, we have clearly shown that alpha-crystallin can function as a molecular chaperone in the reactivation of an oxidatively inactivated protein.


Assuntos
Cristalinas/química , Cristalinas/farmacologia , Ativação Enzimática/efeitos dos fármacos , Reativadores Enzimáticos/química , Peróxido de Hidrogênio/química , Tiossulfato Sulfurtransferase/metabolismo , Trifosfato de Adenosina/química , Naftalenossulfonato de Anilina , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida , Reativadores Enzimáticos/farmacologia , Corantes Fluorescentes , Peróxido de Hidrogênio/farmacologia , Magnésio/química , Mercaptoetanol/química , Chaperonas Moleculares/química , Chaperonas Moleculares/farmacologia , Fenilglioxal/química , Potássio/química , Tiossulfato Sulfurtransferase/química , Tiossulfatos/química
11.
Acta Cytol ; 44(2): 114-23, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10740593

RESUMO

OBJECTIVE: To compare Papanicolaou staining, enzyme immunoassay (EIA) and the polymerase chain reaction (PCR) techniques for detecting Chlamydia trachomatis in pregnant women. STUDY DESIGN: Endocervical specimens were taken randomly from 125 pregnant women with or without symptoms. These women attended their first medical consultation at the Regional General Ignacio Zaragoza Hospital. Samples were analyzed for detection of C trachomatis. When results differed between tests, specimens were evaluated by direct immunofluorescence staining. RESULTS: The prevalence of chlamydial infection was 2.4%. The characteristics of patients positive for Chlamydia were: average age, 24 years; first sexual encounter at age 21 years, one partner and six to nine months of gestation. The sensitivity, specificity, accuracy, positive predictive values and negative predictive values were 100%, 99.18%, 99.20%, 75% and 100%, respectively, for Papanicolaou staining; 100%, 92.62%, 92%, 25% and 100% for EIA; and 100%, 100%, 100% and 100% for PCR. CONCLUSION: Both Papanicolaou staining and PCR were adequate for diagnosis of C trachomatis infection. EIA was not reliable and therefore is not recommended for use as a diagnostic technique in a pregnant population with low risk and low prevalence.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Complicações Infecciosas na Gravidez/diagnóstico , Adulto , Antígenos de Bactérias/análise , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/genética , DNA Bacteriano/análise , Estudos de Avaliação como Assunto , Feminino , Técnica Direta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas/métodos , Teste de Papanicolaou , Reação em Cadeia da Polimerase/métodos , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Esfregaço Vaginal/métodos
12.
Radiol Med ; 96(3): 277, 1998 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-9850729
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