Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 715
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Clin Radiol ; 79(6): 446-452, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38580482

RESUMEN

AIM: This study aimed to assess the imaging features of atypical lipomatous tumors (ALTs) and lipoma with fat necrosis. METHODS: This study included patients with histopathologically proven fat necrosis within adipocytic tumors who underwent preoperative imaging. Magnetic resonance imaging (MRI) and/or computer tomography (CT) findings of fat necrosis associated with lipomatous tumors were retrospectively reviewed, emphasizing the "fatty island sign (FIS)." FISs were defined as well-demarcated, focal fat-containing areas surrounded by more thickened septa compared with other intratumoral septa. Imaging findings of FIS were compared between ALT and lipoma. RESULTS: Fat necrosis was histopathologically confirmed in 17 patients (6 ALTs and 11 lipomas). Among them, 18 FISs were observed in 10 lesions (59%). Multiple FISs within a lesion were observed in 4 (40%) patients. The median maximum diameter of the FISs was 37 mm. Hypointense areas within FISs relative to the subcutaneous fat on T1- and T2-weighted images were observed in 8 (80%) and 9 (90%), respectively, whereas hyperintense areas within FISs on fat-suppressed T2-weighted images were observed in 2 (20%). Nonfatty solid components within FISs were observed in 2 (20%). On CT, increased fat attenuation and pure fat attenuation within FISs were observed in 6 (86%) and 1 (14%), respectively. The imaging findings of FIS were not significantly different between ALT and lipoma. CONCLUSION: FISs were observed in 59% of the histologically proven ALT and lipoma patients with fat necrosis. The hypointense areas relative to the subcutaneous fat on T1- and T2-weighted images and increased fat attenuation on CT were usually observed within FISs.


Asunto(s)
Necrosis Grasa , Lipoma , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Humanos , Femenino , Masculino , Lipoma/diagnóstico por imagen , Lipoma/patología , Persona de Mediana Edad , Necrosis Grasa/diagnóstico por imagen , Necrosis Grasa/patología , Imagen por Resonancia Magnética/métodos , Anciano , Adulto , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
2.
Clin Radiol ; 79(4): e554-e559, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38453389

RESUMEN

AIM: To compare the radiation dose, image quality, and conspicuity of pancreatic ductal adenocarcinoma (PDAC) in pancreatic protocol dual-energy computed tomography (CT) between two X-ray tubes mounted in the same CT machine. MATERIAL AND METHODS: This retrospective study comprised 80 patients (median age, 73 years; 45 men) who underwent pancreatic protocol dual-energy CT from January 2019 to March 2022 using either old (Group A, n=41) or new (Group B, n=39) X-ray tubes mounted in the same CT machine. The imaging parameters were completely matched between the two groups, and CT data were reconstructed at 70 and 40 keV. The CT dose-index volume (CTDIvol); CT attenuation of the abdominal aorta, pancreas, and PDAC; background noise; and qualitative scores for the image noise, overall image quality, and PDAC conspicuity were compared between the two groups. RESULTS: The CTDIvol was lower in Group B than Group A (7.9 versus 9.2 mGy; p<0.001). The CT attenuation of all anatomical structures at 70 and 40 keV was comparable between the two groups (p=0.06-0.78). The background noise was lower in Group B than Group A (12 versus 14 HU at 70 keV, p=0.046; and 26 versus 30 HU at 40 keV, p<0.001). Qualitative scores for image noise and overall image quality at 70 and 40 keV and PDAC conspicuity at 40 keV were higher in Group B than Group A (p<0.001-0.045). CONCLUSION: The latest X-ray tube could reduce the radiation dose and improve image quality in pancreatic protocol dual-energy CT.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Imagen Radiográfica por Emisión de Doble Fotón , Masculino , Humanos , Anciano , Intensificación de Imagen Radiográfica/métodos , Estudios Retrospectivos , Rayos X , Tomografía Computarizada por Rayos X/métodos , Neoplasias Pancreáticas/diagnóstico por imagen , Páncreas/diagnóstico por imagen , Carcinoma Ductal Pancreático/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Dosis de Radiación , Imagen Radiográfica por Emisión de Doble Fotón/métodos
3.
Clin Radiol ; 79(6): e791-e798, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38403540

RESUMEN

AIM: To evaluate arterial enhancement, its depiction, and image quality in low-tube potential whole-body computed tomography (CT) angiography (CTA) with extremely low iodine dose and compare the results with those obtained by hybrid-iterative reconstruction (IR) and deep-learning image-reconstruction (DLIR) methods. MATERIALS AND METHODS: This prospective study included 34 consecutive participants (27 men; mean age, 74.2 years) who underwent whole-body CTA at 80 kVp for evaluating aortic diseases between January and July 2020. Contrast material (240 mg iodine/ml) with simultaneous administration of its quarter volume of saline, which corresponded to 192 mg iodine/ml, was administered. CT raw data were reconstructed using adaptive statistical IR-Veo of 40% (hybrid-IR), DLIR with medium- (DLIR-M), and high-strength level (DLIR-H). A radiologist measured CT attenuation of the arteries and background noise, and the signal-to-noise ratio (SNR) was then calculated. Two reviewers qualitatively evaluated the arterial depictions and diagnostic acceptability on axial, multiplanar-reformatted (MPR), and volume-rendered (VR) images. RESULTS: Mean contrast material volume and iodine weight administered were 64.1 ml and 15.4 g, respectively. The SNRs of the arteries were significantly higher in the following order of the DLIR-H, DLIR-M, and hybrid-IR (p<0.001). Depictions of six arteries on axial, three arteries on MPR, and four arteries on VR images were significantly superior in the DLIR-M or hybrid-IR than in the DLIR-H (p≤0.009 for each). Diagnostic acceptability was significantly better in the DLIR-M and DLIR-H than in the hybrid-IR (p<0.001-0.005). CONCLUSION: DLIR-M showed well-balanced arterial depictions and image quality compared with the hybrid-IR and DLIR-H.


Asunto(s)
Angiografía por Tomografía Computarizada , Medios de Contraste , Aprendizaje Profundo , Dosis de Radiación , Imagen de Cuerpo Entero , Humanos , Masculino , Femenino , Anciano , Estudios Prospectivos , Angiografía por Tomografía Computarizada/métodos , Medios de Contraste/administración & dosificación , Imagen de Cuerpo Entero/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Algoritmos , Persona de Mediana Edad , Anciano de 80 o más Años , Enfermedades de la Aorta/diagnóstico por imagen
4.
Clin Radiol ; 77(2): e138-e146, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34782114

RESUMEN

AIM: To evaluate the computed tomography (CT) attenuation values, background noise, arterial depiction, and image quality in whole-body dual-energy CT angiography (DECTA) at 40 keV with a reduced iodine dose using deep-learning image reconstruction (DLIR) and compare them with hybrid iterative reconstruction (IR). MATERIAL AND METHODS: Whole-body DECTA with a reduced iodine dose (200 mg iodine/kg) was performed in 22 patients, and DECTA data at 1.25-mm section thickness with 50% overlap were reconstructed at 40 keV using 40% adaptive statistical iterative reconstruction with Veo (hybrid-IR group), and DLIR at medium and high levels (DLIR-M and DLIR-H groups). The CT attenuation values of the thoracic and abdominal aortas and iliac artery and background noise were measured. Arterial depiction and image quality on axial, multiplanar reformatted (MPR), and volume-rendered (VR) images were assessed by two readers. Quantitative and qualitative parameters were compared between the hybrid-IR, DLIR-M, and DLIR-H groups. RESULTS: The vascular CT attenuation values were almost comparable between the three groups (p=0.013-0.97), but the background noise was significantly lower in the DLIR-H group than in the hybrid-IR and DLIR-M groups (p<0.001). The arterial depictions on axial and MPR images and in almost all arteries on VR images were comparable (p=0.14-1). The image quality of axial, MPR, and VR images was significantly better in the DLIR-H group (p<0.001-0.015). CONCLUSION: DLIR significantly reduced background noise and improved image quality in DECTA at 40 keV compared with hybrid-IR, while maintaining the arterial depiction in almost all arteries.


Asunto(s)
Enfermedades de la Aorta/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Aprendizaje Profundo , Yodo , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Imagen de Cuerpo Entero/métodos
5.
Clin Radiol ; 76(9): 710.e15-710.e24, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33879322

RESUMEN

AIM: To evaluate the use of deep-learning-based image reconstruction (DLIR) algorithms in dynamic contrast-enhanced computed tomography (CT) of the abdomen, and to compare the image quality and lesion conspicuity among the reconstruction strength levels. MATERIALS AND METHODS: This prospective study included 59 patients with 373 hepatic lesions who underwent dynamic contrast-enhanced CT of the abdomen. All images were reconstructed using four reconstruction algorithms, including 40% adaptive statistical iterative reconstruction-Veo (ASiR-V) and DLIR at low, medium, and high-strength levels (DLIR-L, DLIR-M, and DLIR-H, respectively). The signal-to-noise ratio (SNR) of the abdominal aorta, portal vein, liver, pancreas, and spleen and the lesion-to-liver contrast-to-noise ratio (CNR) were calculated and compared among the four reconstruction algorithms. The diagnostic acceptability was qualitatively assessed and compared among the four reconstruction algorithms and the conspicuity of hepatic lesions was compared between <5 and ≥5 mm lesions. RESULTS: The SNR of each anatomical structure (p<0.0001) and CNR (p<0.0001) were significantly higher in DLIR-H than the other reconstruction algorithms. Diagnostic acceptability was significantly better in DLIR-M than the other reconstruction algorithms (p<0.0001). The conspicuity of hepatic lesions was highest when using 40% ASiR-V and tended to lessen as the reconstruction strength level was getting higher in DLIR, especially in <5 mm lesions; however, all hepatic lesions could be detected. CONCLUSIONS: DLIR improved the SNR, CNR, and image quality compared with 40% ASiR-V, while making it possible to decrease lesion conspicuity using higher reconstruction strength.


Asunto(s)
Neoplasias Abdominales/diagnóstico por imagen , Medios de Contraste , Aprendizaje Profundo , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiografía Abdominal/métodos
6.
Clin Radiol ; 75(4): 320.e17-320.e23, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31879024

RESUMEN

AIM: To evaluate the value of virtual monochromatic images (VMIs) at lower energy levels in fast-voltage-switching dual-energy computed tomography (DECT) for assessing pancreatic ductal adenocarcinoma (PDAC). MATERIALS AND METHODS: The institutional review board approved this prospective study. Written informed consent was obtained from all patients. Seventy-four consecutive patients with PDAC underwent dynamic contrast-enhanced DECT. Two radiologists reviewed eight energy levels (40, 45, 50, 55, 60, 65, 70, and 75 keV) of the pancreatic parenchymal phase VMIs. CT attenuation of the PDAC and pancreatic parenchyma, background noise, signal-to-noise ratio (SNR) of the pancreas, tumour-to-pancreas contrast-to-noise ratio (CNR), major and minor axes of PDAC, and qualitative tumour conspicuity were compared among the VMIs at eight energy levels. RESULTS: CT attenuation of PDAC and pancreatic parenchyma, background noise, SNR, and CNR peaked on VMIs at 40 keV with statistically significant difference (p<0.0001) and gradually decreased with increasing energy levels. The reproducibility in measuring tumour size was better on VMIs at 40 keV (28.8 and 29.2 mm of major axis in readers 1 and 2, respectively) and tended to be overestimated at higher energy levels (29.8 and 30.9 mm of major axis at 75 keV in readers 1 and 2, respectively). Qualitative tumour conspicuity was also significantly superior on VMIs at 40 keV than at all other energy levels (p<0.0001). CONCLUSION: VMIs at 40 keV demonstrated significantly increased SNR of the pancreas, CNR, and tumour conspicuity and high reproducibility in measuring tumour size for assessing PDAC.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Carcinoma Ductal Pancreático/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Relación Señal-Ruido
7.
Neurochem Res ; 44(4): 897-904, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30656593

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease caused by the loss of upper and lower motor neurons resulting in muscle weakness and paralysis. Recently, VGF, a neuropeptide that is a precursor of bioactive polypeptides, was found to be decreased in ALS patients, and its inducer exerted protective effects in models of ALS. These findings suggested that VGF was involved in the pathology of ALS. Here, we investigated the neuroprotective effects of various VGF-derived peptides in an in vitro ALS model. We applied seven VGF-derived peptides (TLQP-21, AQEE-30, AQEE-11, LQEQ-19, QEEL-16, LENY-13, and HVLL-7) to the motor neuron-derived cell line, NSC-34, expressing SOD1G93A, which is one of the mutated proteins responsible for familial ALS. Nuclear staining revealed that AQEE-30 and LQEQ-19, which are derived from the C-terminal polypeptide of the VGF precursor protein, attenuated neuronal cell death. Furthermore, immunoblot analysis demonstrated that LQEQ-19 promoted the phosphorylation of Akt and extracellular signal-regulated kinase (ERK) 1/2, and inhibiting these mitogen-activated MAP kinases (MAPKs) with phosphoinositide 3-kinase or MEK/ERK inhibitors, eliminated the neuroprotective effects of LQEQ-19. In conclusion, these results suggest that VGF C-terminal peptides exert their neuroprotective effects via activation of MAPKs such as Akt and ERK1/2. Furthermore, these findings indicate that VGF-derived peptides have potential application in ALS therapy.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Neuropéptidos/uso terapéutico , Fármacos Neuroprotectores/farmacología , Esclerosis Amiotrófica Lateral/prevención & control , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Ratones , Ratones Transgénicos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Factores de Crecimiento Nervioso , Neuropéptidos/farmacología , Fármacos Neuroprotectores/uso terapéutico , Ratas , Resultado del Tratamiento
8.
Clin Radiol ; 74(6): 490.e1-490.e6, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30914207

RESUMEN

AIM: To evaluate the potential value of magnetic resonance imaging (MRI) for predicting postoperative pancreatic fistula (POPF) in patients with pancreatic cancer (PC) and non-pancreatic cancer (non-PC). MATERIAL AND METHODS: This retrospective study was approved by the institutional review board and written informed consent was waived. Forty patients underwent pancreatoduodenectomy due to PC (n=31) and non-PC (n=9). The pancreas-to-muscle signal intensity ratio (SIR) on three-dimensional (3D)- fast field echo (FFE) T1-, in- and opposed-phase T1-, and T2-weighted images, as well as the apparent diffusion coefficient (ADC) value of the pancreas were measured. The frequency of POPF and MRI measurements were compared between patients with PC and non-PC. The MRI measurements were also compared with the grade of pancreatic fibrosis on pathological findings, fat deposition, and interstitial oedema. RESULTS: The frequency of POPF was significantly higher in patients with non-PC than in those with PC (p=0.0067), with an odds ratio of 10.4. The SIR on 3D-FFE T1-weighted images was significantly higher in patients with non-PC (p=0.0001) and those with POPF (p=0.017) than in those with PC and those without POPF, respectively. Multiple regression analysis demonstrated that the SIR on 3D-FFE T1-weighted image was independently associated with the grade of pancreatic fibrosis (p<0.0001). CONCLUSION: The frequency of POPF was significantly higher in patients with non-PC than in those with PC was inversely related to the grade of pancreatic fibrosis. The SIR on 3D-FFE T1-weighted image might be a potential imaging biomarker for predicting POPF.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Enfermedades Pancreáticas/diagnóstico por imagen , Enfermedades Pancreáticas/patología , Fístula Pancreática/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Fibrosis , Humanos , Masculino , Persona de Mediana Edad , Páncreas/diagnóstico por imagen , Páncreas/patología , Páncreas/cirugía , Enfermedades Pancreáticas/cirugía , Fístula Pancreática/patología , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Complicaciones Posoperatorias/patología
9.
Clin Radiol ; 73(6): 594.e1-594.e6, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29459139

RESUMEN

AIM: To compare right adrenal vein (RAV) visualisation and contrast enhancement degree on adrenal venous phase images reconstructed using adaptive statistical iterative reconstruction (ASiR) and model-based iterative reconstruction (MBIR) techniques. MATERIAL AND METHODS: This prospective study was approved by the institutional review board, and written informed consent was waived. Fifty-seven consecutive patients who underwent adrenal venous phase imaging were enrolled. The same raw data were reconstructed using ASiR 40% and MBIR. The expert and beginner independently reviewed computed tomography (CT) images. RAV visualisation rates, background noise, and CT attenuation of the RAV, right adrenal gland, inferior vena cava (IVC), hepatic vein, and bilateral renal veins were compared between the two reconstruction techniques. RESULTS: RAV visualisation rates were higher with MBIR than with ASiR (95% versus 88%, p=0.13 in expert and 93% versus 75%, p=0.002 in beginner, respectively). RAV visualisation confidence ratings with MBIR were significantly greater than with ASiR (p<0.0001, both in the beginner and the expert). The mean background noise was significantly lower with MBIR than with ASiR (p<0.0001). Mean CT attenuation values of the RAV, right adrenal gland, IVC, and hepatic vein were comparable between the two techniques (p=0.12-0.91). Mean CT attenuation values of the bilateral renal veins were significantly higher with MBIR than with ASiR (p=0.0013 and 0.02). CONCLUSION: Reconstruction of adrenal venous phase images using MBIR significantly reduces background noise, leading to an improvement in the RAV visualisation compared with ASiR.


Asunto(s)
Glándulas Suprarrenales/irrigación sanguínea , Venas/diagnóstico por imagen , Glándulas Suprarrenales/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Angiografía por Tomografía Computarizada/métodos , Venas Hepáticas/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Persona de Mediana Edad , Modelos Teóricos , Tomografía Computarizada Multidetector/métodos , Estudios Prospectivos , Venas Renales/diagnóstico por imagen , Vena Cava Inferior/diagnóstico por imagen , Adulto Joven
10.
Clin Radiol ; 72(10): 901.e13-901.e19, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28673448

RESUMEN

AIM: To compare contrast enhancement and image quality between renovascular computed tomography (CT) images with adaptive statistical iterative reconstruction (ASiR) and that with model-based iterative reconstruction (MBIR). MATERIAL AND METHODS: This retrospective study was approved by the institutional review board and written informed consent was waived. Twenty-five consecutive patients who underwent renovascular CT were enrolled in this study. The same raw projection data were reconstructed using ASiR 40%, 100%, and MBIR. Background noise, CT attenuation, and signal-to-noise ratio (SNR) of the renal vessels and kidneys, and image quality were compared among the three reconstruction techniques. RESULTS: Mean background noise was significantly lower with MBIR at the first and second phases than those with ASiR 40% and 100% (p<0.0001). Mean CT attenuation of the abdominal aorta, renal artery, and renal cortex obtained at the first phase and those of the renal vein and renal medulla at the second phase were comparable among the three techniques (p=0.051-1.00). Mean SNRs of the abdominal aorta, renal artery, renal cortex, renal vein, and renal medulla were significantly higher with MBIR than with ASiR 40% or 100% (both p<0.0001). The depiction of the renal artery and vein as well as image quality significantly improved with MBIR compared with those with ASiR 40% and 100% (p<0.0001-0.0016). CONCLUSION: Reconstruction of renovascular CT images with MBIR significantly reduces background noise, leading to an improvement in SNR and image quality compared with that using ASiR.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Riñón/irrigación sanguínea , Riñón/diagnóstico por imagen , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Aorta Abdominal/diagnóstico por imagen , Femenino , Humanos , Médula Renal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Arteria Renal/diagnóstico por imagen , Venas Renales/diagnóstico por imagen , Reproducibilidad de los Resultados , Estudios Retrospectivos , Relación Señal-Ruido
11.
Psychol Med ; 45(16): 3411-32, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26349810

RESUMEN

Depression is one of the most prevalent mental illnesses worldwide and a leading cause of disability, especially in the setting of treatment resistance. In recent years, repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising alternative strategy for treatment-resistant depression and its clinical efficacy has been investigated intensively across the world. However, the underlying neurobiological mechanisms of the antidepressant effect of rTMS are still not fully understood. This review aims to systematically synthesize the literature on the neurobiological mechanisms of treatment response to rTMS in patients with depression. Medline (1996-2014), Embase (1980-2014) and PsycINFO (1806-2014) were searched under set terms. Three authors reviewed each article and came to consensus on the inclusion and exclusion criteria. All eligible studies were reviewed, duplicates were removed, and data were extracted individually. Of 1647 articles identified, 66 studies met both inclusion and exclusion criteria. rTMS affects various biological factors that can be measured by current biological techniques. Although a number of studies have explored the neurobiological mechanisms of rTMS, a large variety of rTMS protocols and parameters limits the ability to synthesize these findings into a coherent understanding. However, a convergence of findings suggest that rTMS exerts its therapeutic effects by altering levels of various neurochemicals, electrophysiology as well as blood flow and activity in the brain in a frequency-dependent manner. More research is needed to delineate the neurobiological mechanisms of the antidepressant effect of rTMS. The incorporation of biological assessments into future rTMS clinical trials will help in this regard.


Asunto(s)
Antidepresivos/uso terapéutico , Depresión/terapia , Trastorno Depresivo Resistente al Tratamiento/terapia , Corteza Prefrontal/fisiopatología , Estimulación Magnética Transcraneal , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Nature ; 451(7180): 805-8, 2008 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-18273014

RESUMEN

The motion of atoms in a solid always responds to cooling or heating in a way that is consistent with the symmetry of the given space group of the solid to which they belong. When the atoms move, the electronic structure of the solid changes, leading to different physical properties. Therefore, the determination of where atoms are and what atoms do is a cornerstone of modern solid-state physics. However, experimental observations of atomic displacements measured as a function of temperature are very rare, because those displacements are, in almost all cases, exceedingly small. Here we show, using a combination of diffraction techniques, that the hexagonal manganites RMnO3 (where R is a rare-earth element) undergo an isostructural transition with exceptionally large atomic displacements: two orders of magnitude larger than those seen in any other magnetic material, resulting in an unusually strong magneto-elastic coupling. We follow the exact atomic displacements of all the atoms in the unit cell as a function of temperature and find consistency with theoretical predictions based on group theories. We argue that this gigantic magneto-elastic coupling in RMnO3 holds the key to the recently observed magneto-electric phenomenon in this intriguing class of materials.

13.
Endoscopy ; 45(5): 335-41, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23468193

RESUMEN

BACKGROUND AND STUDY AIMS: Carbon dioxide (CO2) insufflation is expected to be safe and effective in endoscopic submucosal dissection (ESD) as well as in other endoscopic procedures. The present study aimed to clarify the usefulness and safety of CO2 insufflation in gastric ESD. PATIENTS AND METHODS: A total of 102 consecutive patients were randomly assigned to CO2 insufflation (CO2 group, n = 54) or air insufflation (Air group, n = 48). Abdominal pain and distension were chronologically recorded on a 100-mm visual analog scale (VAS). The volume of residual gas in the digestive tract was measured by computed tomography performed immediately after ESD. RESULTS: Abdominal pain on a 100-mm VAS in the CO2 vs. Air group was 4 vs. 3 immediately after ESD, 4 vs. 4 one hour after the procedure, 3 vs. 3 three hours after the procedure, and 1 vs. 4 the next morning, showing no difference between the groups. In addition, there was no difference in abdominal distension on the 100-mm VAS over the time course of the study. The volume of residual gas in the digestive tract in the CO2 group was significantly smaller than that in the Air group (643 mL vs. 1037 mL, P < 0.001). The dose of sedative drugs did not differ between the groups. Neither the incidences of complications nor clinical courses differed between the groups. CONCLUSIONS: Compared with air insufflation, CO2 insufflation during gastric ESD significantly reduced the volume of residual gas in the digestive tract but not the VAS score of abdominal pain and distension.


Asunto(s)
Dióxido de Carbono , Gases , Mucosa Gástrica/cirugía , Insuflación/métodos , Neoplasias Gástricas/cirugía , Dolor Abdominal/etiología , Anciano , Anciano de 80 o más Años , Aire , Dióxido de Carbono/efectos adversos , Disección , Método Doble Ciego , Femenino , Gases/efectos adversos , Gastroscopía , Humanos , Insuflación/efectos adversos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/etiología , Factores de Tiempo
14.
Clin Oncol (R Coll Radiol) ; 35(10): e601-e610, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37587000

RESUMEN

AIMS: To evaluate computed tomography (CT) and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) findings of invasive non-mucinous adenocarcinoma (INMA) of the lung as a predictor of histological tumour grade according to 2021 World Health Organization (WHO) classification. MATERIALS AND METHODS: This retrospective study included consecutive patients with surgically resected INMA who underwent both preoperative CT and 18F-FDG-PET/CT. A three-tiered tumour grade was performed based on the fifth edition of the WHO classification of lung tumours. CT imaging features and the maximum standardised uptake value (SUVmax) were compared among the three tumour grades. RESULTS: In total, 214 patients with INMA (median age 70 years; interquartile range 65-76 years; 123 men) were histologically categorised: 36 (17%) as grade 1, 102 (48%) as grade 2 and 76 (35%) as grade 3. Pure solid appearance was more frequent in grade 3 (83%) than in grades 1 (0%) and 2 (26%) (P < 0.001). The SUVmax of the entire tumour was higher in grade 3 than in grades 1 and 2 (P < 0.001). Multivariable analysis revealed that pure solid appearance (odds ratio = 94.0; P < 0.001), round/oval shape (odds ratio = 4.01; P = 0.001), spiculation (odds ratio = 2.13; P = 0.04), air bronchogram (odds ratio = 0.40; P = 0.03) and SUVmax (odds ratio = 1.45; P < 0.001) were significant predictors for grade 3 INMAs. CONCLUSION: Pure solid appearance, round/oval shape, spiculation, absence of air bronchogram and high SUVmax were associated with grade 3 INMAs. CT and 18F-FDG-PET/CT were potentially useful non-invasive imaging methods to predict the histological grade of INMAs.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Masculino , Humanos , Anciano , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Estudios Retrospectivos , Adenocarcinoma del Pulmón/diagnóstico por imagen , Adenocarcinoma del Pulmón/cirugía , Tomografía Computarizada por Rayos X , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Biomarcadores , Organización Mundial de la Salud , Pulmón
15.
Clin Exp Allergy ; 42(8): 1217-26, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22805469

RESUMEN

BACKGROUND: Lipopolysaccharide (LPS) has shown heterogeneous effects on eosinophilic inflammation in airways. However, little is known about how LPS regulates pathogenesis of chronic rhinosinusitis with nasal polyps, a major form of eosinophilic inflammation in the upper airway. OBJECTIVE: We sought to investigate the effect of LPS on cytokine production by dispersed nasal polyp cells (DNPCs). METHODS: Either diclofenac-treated or untreated DNPCs were cultured with or without staphylococcal enterotoxin B (SEB) in the presence or absence of LPS, after which the levels of IL-5, IL-13, IL-17A and IFN-γ within the supernatant were measured. The effects of PGE(2) on LPS-induced responses by diclofenac-treated DNPCs were also examined. LPS-induced PGE(2) production and mRNA expression of COX-1, COX-2 and microsomal PGE(2) synthase-1 (m-PGES-1) were measured. RESULTS: Staphylococcal enterotoxin B induced IL-5, IL-13, IL-17A and IFN-γ production by DNPCs. Pre-treatment with LPS prior to SEB stimulation inhibited production of these cytokines. After stimulation with LPS, PGE(2) production and expression of COX-2 and m-PGES-1 mRNA by DNPCs increased significantly. In the presence of diclofenac, the suppressive effects of LPS were eliminated. LPS pre-treatment enhanced SEB-induced IL-5, IL-13 and IL-17A production in diclofenac-treated DNPCs, while addition of PGE(2) inhibited IL-5, IL-13 and IFN-γ production. LPS alone induced IL-5, IL-13 and IFN- γ production by diclofenac-treated DNPCs, while the addition of EP2 and EP4 receptor-selective agonists, as well as PGE(2) itself, inhibited IL-5 and IL-13 production. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that the regulatory effects of LPS on eosinophilic airway inflammation are controlled via the COX-2/PGE(2) axis. For clinical implications, indiscreet use of non-steroidal anti-inflammatory drugs should be avoided in patients with chronic rhinosinusitis with nasal polyps.


Asunto(s)
Citocinas/biosíntesis , Dinoprostona/metabolismo , Eosinofilia/inmunología , Lipopolisacáridos/inmunología , Pólipos Nasales/inmunología , Pólipos Nasales/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Adolescente , Adulto , Anciano , Células Cultivadas , Ciclooxigenasa 1/genética , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Citocinas/inmunología , Enterotoxinas/inmunología , Eosinofilia/metabolismo , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Lipopolisacáridos/farmacología , Masculino , Persona de Mediana Edad , Prostaglandina-Endoperóxido Sintasas/genética , Subtipo EP2 de Receptores de Prostaglandina E/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Transducción de Señal/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Células Th2/inmunología , Células Th2/metabolismo , Adulto Joven
16.
Clin Exp Allergy ; 42(2): 315-25, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22092376

RESUMEN

BACKGROUND: The chemokine receptor CCR4 has been implicated in Th2 cell-mediated immune responses. However, other T cell subsets are also known to participate in allergic inflammation. OBJECTIVE: The role of CCR4 in Th1, Th2, and Th17 cell-mediated allergic airway inflammation was investigated. METHOD: We generated an allergic airway inflammation model by adoptive transfer of in vitro-polarized ovalbumin (OVA)-specific Th1, Th2, and Th17 cells. The effect of a low-molecular weight CCR4 antagonist, Compound 22, on this model was examined. RESULTS: Upon in vitro polarization of DO11.10 naïve T cells, Th1- and Th2-polarized cells dominantly expressed CXCR3 and CCR4, respectively, while Th17-polarized cells expressed CCR6 and CCR4. Intranasal OVA-challenge of mice transferred with each T cell subset induced accumulation of T cells in the lungs. Eosinophils were also massively accumulated in Th2-transferred mice, whereas neutrophils were preferentially recruited in Th1- and Th17-transferred mice. Compound 22, as well as anti-CCL17 or anti-CCL22 antibody selectively suppressed accumulation of Th2 cells and eosinophils in the lungs of Th2-transferred and OVA-challenged mice. Compound 22 also inhibited bronchial hyperresponsiveness but had little effect on goblet cell hyperplasia in Th2-transferred and OVA-challenged mice. CONCLUSIONS AND CLINICAL RELEVANCE: There were notable differences in allergic lung inflammation mediated by different T cell subsets. CCR4 blockage was selectively effective for suppression of Th2-mediated allergic inflammation by blocking infiltration of Th2 cells.


Asunto(s)
Regulación hacia Abajo/inmunología , Receptores CCR4/antagonistas & inhibidores , Hipersensibilidad Respiratoria/tratamiento farmacológico , Células Th2/inmunología , Traslado Adoptivo , Animales , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Células Caliciformes/inmunología , Células Caliciformes/patología , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/inmunología , Inflamación/patología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Receptores CCR4/genética , Receptores CCR4/inmunología , Receptores CCR6/antagonistas & inhibidores , Receptores CCR6/genética , Receptores CCR6/inmunología , Hipersensibilidad Respiratoria/genética , Hipersensibilidad Respiratoria/inmunología , Hipersensibilidad Respiratoria/patología , Células TH1/inmunología , Células TH1/patología , Células Th17/inmunología , Células Th17/patología , Células Th2/patología
17.
Endoscopy ; 44(6): 565-71, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22407383

RESUMEN

BACKGROUND AND AIMS: Mediastinal emphysema sometimes develops following esophageal endoscopic submucosal dissection (ESD) without perforation because the esophagus has no serosa. Carbon dioxide (CO2) insufflation during esophageal ESD may reduce the incidence of mediastinal emphysema. The aim of the present study was to compare the incidence and severity of post-ESD mediastinal emphysema in patients receiving CO2 insufflation vs. standard air insufflation during esophageal ESD. PATIENTS AND METHODS: A total of 27 patients who had undergone esophageal ESD with insufflation of CO2 between July 2009 and March 2010 were enrolled in this study (CO2 group). Another 105 patients who had undergone esophageal ESD with air insufflation between March 2004 and May 2009 were included as historical controls (air group). Multi-detector row computed tomography (MDCT) was carried out immediately after ESD. A conventional chest radiograph was taken the next day. Mediastinal emphysema findings on MDCT and radiography were compared between the groups. RESULTS: Mediastinal emphysema detected by chest radiography was 0 % in the CO2 group vs. 6.6 % in the air group (n.s.). Mediastinal emphysema on MDCT was significantly less frequent in the CO2 group compared with the air group (30 % vs. 63 %; P = 0.002). The severity of mediastinal emphysema also tended to be lower in the CO2 group. CONCLUSIONS: Whereas mediastinal emphysema detected by radiography is not so common, MDCT immediately after ESD revealed a certain prevalence of post-ESD mediastinal emphysema. Insufflation of CO2 rather than air during esophageal ESD significantly reduced postprocedural mediastinal emphysema. CO2 can be considered as insufflating gas for esophageal ESD.


Asunto(s)
Adenocarcinoma/cirugía , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Insuflación/efectos adversos , Enfisema Mediastínico/etiología , Membrana Mucosa/cirugía , Anciano , Aire , Dióxido de Carbono , Distribución de Chi-Cuadrado , Disección/efectos adversos , Femenino , Humanos , Masculino , Enfisema Mediastínico/diagnóstico por imagen , Enfisema Mediastínico/prevención & control , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Proyectos Piloto , Índice de Severidad de la Enfermedad
18.
J Clin Pharm Ther ; 37(1): 112-6, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21385196

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Montelukast, a cysteinyl leukotriene receptor 1 antagonist, is safe and efficacious in patients with asthma. The mechanisms underlying the significant interpatient variability in response to montelukast are not clear but are believed to be, in part, because of genetic variability. METHODS: To examine the associations between polymorphisms in candidate genes in the leukotriene pathway and outcomes in patients with asthma on montelukast for 4-8 weeks, we evaluated the changes in peak expiratory flow (PEF), forced expiratory volume in 1 s (FEV(1·0) ) and patients' subjective symptom before and after montelukast treatment. DNA was collected from 252 Japanese participants. RESULTS AND DISCUSSION: Two single-nucleotide polymorphisms (SNPs) in the ALOX5 (rs2115819) and LTA4H (rs2660845) genes were successfully typed. There was no difference between members of the general population (n = 200) and patients (n = 52) in each genotype frequency. Significant associations were found between SNP genotypes in the LTA4H gene and changes in PEF and FEV(1·0) . The PEF and FEV(1·0) responses to montelukast in the A/A genotypes (n = 4) for the LTA4H SNP were significantly higher than those in the G allele carriers (A/G+G/G) (n = 17). WHAT IS NEW AND CONCLUSION: Despite the small sample size, our results suggest that genetic variation in leukotriene pathway candidate genes contributes to variability in clinical responses to montelukast in Japanese patients with asthma.


Asunto(s)
Acetatos/farmacología , Antiasmáticos/farmacología , Araquidonato 5-Lipooxigenasa/genética , Asma/tratamiento farmacológico , Epóxido Hidrolasas/genética , Quinolinas/farmacología , Acetatos/uso terapéutico , Adulto , Anciano , Alelos , Antiasmáticos/uso terapéutico , Pueblo Asiatico/genética , Asma/genética , Ciclopropanos , Femenino , Volumen Espiratorio Forzado/efectos de los fármacos , Genotipo , Humanos , Japón , Antagonistas de Leucotrieno/farmacología , Antagonistas de Leucotrieno/uso terapéutico , Leucotrienos/genética , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio/efectos de los fármacos , Polimorfismo de Nucleótido Simple , Quinolinas/uso terapéutico , Análisis de Secuencia de ADN , Sulfuros , Resultado del Tratamiento
19.
J Clin Pharm Ther ; 37(1): 49-52, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21332567

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Renal impairment is unavoidable after laparoscopic radical nephrectomy (LRN) and is an important consideration for drug therapy. It is possible that the renal impairment after LRN causes adverse reactions following reduced elimination of some renally excreted drugs, such as hypoglycaemic drugs. However, there are few studies of renal function in patients with diabetes mellitus (DM) in the first week after LRN. The purpose of this study was to examine whether renal impairment after LRN affected glycaemic control. We assessed pre- and postoperative renal function of DM patients and examined whether re-administration of hypoglycaemic drugs in the first week after LRN causes episodes of hypoglycaemia. METHODS: Renal carcinoma patients undergoing LRN in Nagoya University Hospital from January 2007 to December 2009 were identified in a retrospective cohort study design. Patients were divided into non-DM (n = 60) and DM (n = 14) groups. RESULTS AND DISCUSSION: There were significant differences in postoperative estimated glomerular filtration rate values between the non-DM and DM groups. Four of nine patients (44%) experienced hypoglycaemia induced by re-administration of hypoglycaemic drugs, namely, sulfonylureas. WHAT IS NEW AND CONCLUSION: In the present study, we found the first evidence that renal impairment in the first week after LRN was a risk factor of hypoglycaemia. To prevent hypoglycaemia after LRN, assessment of renal function and the use of insulin therapy are important.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Hipoglucemia/etiología , Hipoglucemiantes/farmacología , Nefrectomía/efectos adversos , Anciano , Estudios de Cohortes , Femenino , Tasa de Filtración Glomerular , Hospitales Universitarios , Humanos , Hipoglucemiantes/farmacocinética , Neoplasias Renales/cirugía , Laparoscopía/efectos adversos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Nefrectomía/métodos , Insuficiencia Renal/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Compuestos de Sulfonilurea/farmacocinética , Compuestos de Sulfonilurea/farmacología
20.
Poult Sci ; 91(10): 2444-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22991526

RESUMEN

Vaccination of poultry is one promising strategy to mitigate Salmonella infection in poultry and, in turn, humans as well. We evaluated the efficacy of outer membrane protein A (OmpA) as a novel vaccine candidate against Salmonella in poultry. Native OmpA purified from Salmonella enterica serovar Enteritidis was mixed with adjuvant and administered intramuscularly to 41-d-old chicks. The vaccinated birds showed no decrease in cecal excretion and tissue colonization compared with the unvaccinated birds after oral challenge with 10(9) cfu of the homologous strain at 28 d postimmunization. However, this vaccination induced an increased level of serum anti-OmpA IgG. Similar results were obtained in the replication experiments using a recombinant OmpA with single and double doses. For the development of more effective component vaccines for avian salmonellosis, the vaccine efficacy of outer membrane proteins other than OmpA and route of immunization other than parenteral administration should be evaluated with regard to protection and immune responses, including mucosal IgA.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/inmunología , Pollos , Enfermedades de las Aves de Corral/prevención & control , Salmonelosis Animal/prevención & control , Salmonella enteritidis/metabolismo , Animales , Inmunidad Humoral , Inmunización , Enfermedades de las Aves de Corral/microbiología , Proteínas Recombinantes/inmunología , Salmonelosis Animal/microbiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA