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1.
Radiat Prot Dosimetry ; 187(1): 1-7, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31034554

RESUMEN

Prostatic artery embolisation (PAE) is used to treat patients with benign prostatic hyperplasia and with lower urinary obstructive tract symptoms. It is an interventional procedure which uses fluoroscopy equipment and can result in exposure to high doses of radiation in patients and staff. We aimed to demonstrate the reduction of radiation doses received by staff during PAE by implementing an optimised protocol called Radiation Exposure Curtailment for Embolisation (RECiFE). This protocol was implemented in cooperation with the medical team and technical team using Siemens Combined Applications to Reduce Exposure (CARE) protocol. The results showed approximately 83% reduction in the radiation doses received by the main physician during PAE. Thus, by adjusting the acquisition parameters of the angiographic equipment and implementing the RECiFE protocol, it is possible to optimise the PAE procedure and reduce the staff radiation dose.


Asunto(s)
Embolización Terapéutica/efectos adversos , Exposición Profesional/efectos adversos , Fantasmas de Imagen , Hiperplasia Prostática/terapia , Exposición a la Radiación/efectos adversos , Protección Radiológica/métodos , Radiografía Intervencional/efectos adversos , Brasil , Humanos , Masculino
2.
Cytokine ; 113: 61-67, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29935876

RESUMEN

BACKGROUND AND AIMS: Macrophages derived from monocytes play an important role in atherosclerosis progression. Subpopulations of circulating classical, intermediate, and non-classical monocytes possess distinct functions and phenotypes, and participate in the pathogenesis of disease. The aim of this study was to compare the quantity and phenotypes of circulating monocyte subpopulations in patients with established atherosclerosis and healthy control individuals. Additionally, the study aimed to provide insight into the functional activity of monocytes against a heat shock protein (HSP60). METHODS: Chemokine and pattern recognition receptors in monocyte subsets obtained from peripheral blood of acute and chronic coronary artery disease patients and controls were quantified by flow cytometry. Furthermore, monocytes from healthy controls were stimulated in vitro with HSP60, and the cytokines produced by them were evaluated by flow cytometry. RESULTS: Eighteen controls (C), 34 individuals with risk factors for cardiovascular disease (RF), 32 patients with stable angina (SA), and 16 patients with unstable angina (UA) were enrolled in the study. The absolute count of intermediate monocytes was found to be increased in patients of the UA group; high frequencies of the chemokine receptors CCR2, CCR5, and CX3CR1 were also observed in this subpopulation. Moreover, the pattern recognition receptors TLR2 and TLR4 were more frequent in intermediate monocytes from the UA group. Furthermore, the intermediate monocytes from healthy individuals produced IL-12p70 after stimulation with HSP60. CONCLUSIONS: Our results show that intermediate monocytes of UA patients exhibited an enhanced expression of the receptors involved in the recognition of damage-associated molecular patterns (DAMPs) and enhancement of the migratory function. Hence, they might contribute to the propagation and progression of inflammation observed in atherosclerosis, especially in the acute setting.


Asunto(s)
Angina Inestable/metabolismo , Quimiocinas/metabolismo , Monocitos/metabolismo , Receptores de Reconocimiento de Patrones/metabolismo , Receptor 1 de Quimiocinas CX3C/metabolismo , Chaperonina 60/metabolismo , Femenino , Humanos , Interleucina-12/metabolismo , Masculino , Persona de Mediana Edad , Receptores CCR2/metabolismo , Receptores CCR5/metabolismo , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/metabolismo
3.
Clin Exp Immunol ; 183(2): 248-57, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26437614

RESUMEN

Respiratory syncytial virus (RSV)-specific CD8(+) T cell responses do not protect against reinfection. Activation of mammalian target of rapamycin (mTOR) impairs memory CD8(+) T cell differentiation. Our hypothesis was that RSV inhibits the formation of CD8(+) T cells memory responses through mTOR activation. To explore this, human and mouse T cells were used. RSV induced mTOR phosphorylation at Ser2448 in CD8 T cells. mTOR activation by RSV was completely inhibited using rapamycin. RSV-infected children presented higher mTOR gene expression on nasal washes comparing to children infected with metapneumovirus and rhinovirus. In addition, RSV-infected infants presented a higher frequency of CD8(+) pmTORser2448(+) T cells in nasal washes compared to RSV-negative infants. Rapamycin treatment increased the frequency of mouse CD8 RSV-M282-90 pentamer-positive T cells and the frequency of RSV-specific memory T cells precursors. These data demonstrate that RSV is activating mTOR directly in CD8 T cells, indicating a role for mTOR during the course of RSV infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Líquido del Lavado Nasal/inmunología , Infecciones por Virus Sincitial Respiratorio/inmunología , Infecciones por Virus Sincitial Respiratorio/metabolismo , Virus Sincitiales Respiratorios/inmunología , Serina-Treonina Quinasas TOR/metabolismo , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Niño , Humanos , Memoria Inmunológica/efectos de los fármacos , Inmunosupresores/farmacología , Lactante , Activación de Linfocitos/efectos de los fármacos , Ratones , Líquido del Lavado Nasal/virología , Fosforilación , Infecciones por Virus Sincitial Respiratorio/virología , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/genética
4.
Br J Radiol ; 88(1053): 20150269, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26118302

RESUMEN

OBJECTIVE: To assess whether an online open-source tool would provide accurate calculations of T2(*) values for iron concentrations in the liver and heart compared with a standard reference software. METHODS: An online open-source tool, written in pure HTML5/Javascript, was tested in 50 patients (age 26.0 ± 18.9 years, 46% males) who underwent T2(*) MRI of the liver and heart for iron overload assessment as part of their routine workup. Automated truncation correction was the default with optional manual adjustment provided if needed. The results were compared against a standard reference measurement using commercial software with manual truncation (CVI(42)(®) v. 5.1; Circle Cardiovascular Imaging; Calgary, AB). RESULTS: The mean liver T2(*) values calculated with the automated tool was 4.3 ms [95% confidence interval (CI) 3.1 to 5.5 ms] vs 4.26 ms using the reference software (95% CI 3.1 to 5.4 ms) without any significant differences (p = 0.71). In the liver, the mean difference was 0.036 ms (95% CI -0.1609 to 0.2329 ms) with a regression correlation coefficient of 0.97. For the heart, the automated T2(*) value was 26.0 ms (95% CI 22.9 to 29.0 ms) vs 25.3 ms (95% CI 22.3 to 28.3 ms), p = 0.28. The mean difference was 0.72 ms (95% CI 0.08191 to 1.3621 ms) with a correlation coefficient of 0.96. CONCLUSION: The automated online tool provides similar T2(*) values for the liver and myocardial iron concentrations as compared with a standard reference software. ADVANCES IN KNOWLEDGE: The online program provides an open-source tool for the calculation of T2(*) values, incorporating an automated correction algorithm in a simple and easy-to-use interface.


Asunto(s)
Sobrecarga de Hierro/diagnóstico , Hierro/análisis , Hígado/química , Imagen por Resonancia Magnética/métodos , Miocardio/química , Adolescente , Adulto , Niño , Femenino , Humanos , Internet , Hígado/metabolismo , Masculino , Miocardio/metabolismo , Adulto Joven
5.
Phys Rev Lett ; 114(16): 162501, 2015 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-25955048

RESUMEN

It has been understood since 1897 that accelerating charges must emit electromagnetic radiation. Although first derived in 1904, cyclotron radiation from a single electron orbiting in a magnetic field has never been observed directly. We demonstrate single-electron detection in a novel radio-frequency spectrometer. The relativistic shift in the cyclotron frequency permits a precise electron energy measurement. Precise beta electron spectroscopy from gaseous radiation sources is a key technique in modern efforts to measure the neutrino mass via the tritium decay end point, and this work demonstrates a fundamentally new approach to precision beta spectroscopy for future neutrino mass experiments.

6.
Transplant Proc ; 42(2): 407-11, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20304152

RESUMEN

BACKGROUND: Since July 2006, the Model for End-stage Liver Disease (MELD) score has served as the national basis for allocation of donor livers for transplantation in Brazil. Patients with higher MELD scores receive greater priority for allocation regardless of the time on the waiting list. PURPOSE: To investigate the impact of MELD score implementation on the survival of waiting list patients. METHODS: A retrospective study of patients registered at the national Organ Procurement Organization (OPO) for the liver transplantation waiting list between January 2004 and June 2006 (pre-MELD) and between July 2006 and December 2008 (post-MELD). RESULTS: We included listed patients awaiting liver transplantation in the pre-MELD era (n = 250, 48.4%) and in the post-MELD era (n = 266, 51.6%). The times awaiting transplant prior to and after the MELD system were 487.2 +/- 384.8 days and 183.9 +/- 157.2 days, respectively. Prior to the MELD score, waiting list survivals were greater when compared to rates in the current system. Early posttransplant patient survival rates were significantly reduced in the post-MELD era (83.4%) compared to the period before MELD implementation (93.2%). CONCLUSIONS: MELD score provides a transparent, objective system to drive allocation policy; however, it presents several important limitations. Constant need of changes and reevaluation are needed as an evolutionary process. Future changes in the present system may be addressed by adjusting the MELD system.


Asunto(s)
Fallo Hepático/cirugía , Trasplante de Hígado/estadística & datos numéricos , Listas de Espera , Adolescente , Adulto , Anciano , Cadáver , Niño , Preescolar , Femenino , Humanos , Fallo Hepático/mortalidad , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Asignación de Recursos/métodos , Estudios Retrospectivos , Tasa de Supervivencia , Sobrevivientes , Donantes de Tejidos/estadística & datos numéricos
7.
BMJ Case Rep ; 2009: bcr2006091835, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-21687118
8.
Acta Radiol ; 49(1): 75-9, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18210315

RESUMEN

Although imaging and clinical criteria are already established for the diagnosis of mucoid degeneration of the anterior cruciate ligament (ACL), many radiologists remain unaware of their existence. Once regarded as a rare occurrence, it has been recently suggested that its incidence is in fact very much higher than previously thought, and that it is probably underdiagnosed or misdiagnosed as partial ruptures of the ACL or as cystic ganglia. In this review, the authors revisit the literature concerning this subject and present their personal experience with it, stressing the paramount importance of magnetic resonance imaging and correlation with clinical data for a correct diagnosis.


Asunto(s)
Ligamento Cruzado Anterior/patología , Artropatías/diagnóstico , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Envejecimiento , Diagnóstico Diferencial , Ganglión/diagnóstico , Humanos , Moco , Rango del Movimiento Articular
9.
JBR-BTR ; 91(6): 245-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19202998

RESUMEN

In this report seven cases of diffusely altered signal intensity of the posterior cruciate ligament (PCL) at magnetic resonance imaging (MRI) are described. The abnormalities resemble those of mucoid degeneration of the anterior cruciate ligament (ACL) and are associated with it in six cases. Although mucoid degeneration of the ACL is an increasingly reported entity, with well-established imaging criteria at MRI, to the authors' knowledge similar findings were never described before for the PCL. It is hypothesized that these abnormalities of the cruciate ligaments are similar in nature, probably related to degenerative changes of the connective tissue.


Asunto(s)
Ligamento Cruzado Anterior/patología , Enfermedades del Tejido Conjuntivo/diagnóstico , Artropatías/diagnóstico , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Ligamento Cruzado Posterior/patología , Adulto , Anciano , Enfermedades del Tejido Conjuntivo/complicaciones , Femenino , Humanos , Artropatías/complicaciones , Masculino , Persona de Mediana Edad , Dolor/etiología , Rango del Movimiento Articular
12.
Int Orthop ; 21(6): 389-92, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9498149

RESUMEN

Seventy-one hip joints in 69 infants and children with pyogenic arthritis were studied. Twenty joints (28%) with the radiographic characteristics of avascular necrosis were identified and the changes classified into 3 groups: Group 1 (infants up to the age of 6 months) had ischaemic changes characterized by the absence or delayed appearance of the epiphyseal ossification centre; Group 2 (children aged between 7 months and 5 years) showed disappearance of this centre whether followed by revascularization or not, with the shape of the cartilaginous femoral head preserved in either case; and in Group 3 (children 6-16 years of age) the femoral epiphysis was either totally or partially involved with increased bone density; collapse of the head may or may not have occurred. At follow-up for between 2 and 15 years, a trend towards more severe deformities was seen in the 11 hip joints of Group 3 when compared to the 9 hip joints in Groups 1 and 2. The opposite was observed in relation to less severe deformities. Early diagnosis and treatment of infection is mandatory in patients with pyogenic arthritis and increased intra-articular hydrostatic pressure, or those with septic thrombosis of the epiphyseal vessels, which could cause avascular necrosis (AVN).


Asunto(s)
Artritis Infecciosa/complicaciones , Necrosis de la Cabeza Femoral/etiología , Articulación de la Cadera , Infecciones Estafilocócicas/complicaciones , Adolescente , Distribución por Edad , Artritis Infecciosa/diagnóstico por imagen , Artritis Infecciosa/terapia , Brasil/epidemiología , Niño , Preescolar , Femenino , Necrosis de la Cabeza Femoral/diagnóstico por imagen , Necrosis de la Cabeza Femoral/epidemiología , Necrosis de la Cabeza Femoral/terapia , Humanos , Incidencia , Lactante , Masculino , Radiografía , Factores de Riesgo , Distribución por Sexo , Infecciones Estafilocócicas/diagnóstico por imagen , Infecciones Estafilocócicas/terapia
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