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1.
Clin Radiol ; 74(10): 816.e1-816.e8, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31400805

RESUMEN

AIM: To evaluate the diagnostic feasibility of probabilistic analysis using voxel-based morphometry (VBM) in differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma (GBM). MATERIALS AND METHODS: In total, 118 patients with GBM (57 males, 61 females; mean [± standard deviation] age, 56.9±19.3 years; median, 61 years) and 52 patients with PCNSL (37 males, 15 females; mean age, 62±13.3 years, median, 66 years) were studied retrospectively. Each patient underwent preoperative contrast-enhanced T1-weighted imaging (CE-T1WI) using a 1.5 or 3 T magnetic resonance imaging (MRI) system. To assess preferential occurrence sites, images from CE-T1WI were co-registered and spatially normalised using the MNI152 T1 template. Subsequently, a region of interest (ROI) was placed in the centre of the enhancing tumour in normalised images with 1-mm isotropic resolution. The same ROI between normalised and T1 template images was set up using an ROI manager function in ImageJ software. A spherical volume of interest (VOI) with a radius of 10 mm was determined. A probability map was created by overlaying each image with the VOI. Each VOI was removed from T1 template images for VBM analysis. VBM analysis was performed using statistical parametric mapping (SPM) 12 software under default settings. RESULTS: VBM analysis showed significantly higher frequency in the splenium of the corpus callosum among PCNSL patients than among GBM patients (p<0.05; family-wise error correction). CONCLUSION: Topographic analysis using VBM provides useful information for differentiating PCNSL from GBM.


Asunto(s)
Mapeo Encefálico , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias del Sistema Nervioso Central/diagnóstico por imagen , Glioblastoma/diagnóstico por imagen , Linfoma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Estudios de Factibilidad , Femenino , Sustancia Gris/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
2.
Clin Radiol ; 72(3): 223-229, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27889091

RESUMEN

AIM: To assess single-breath-hold combined positron-emission tomography/computed tomography (PET/CT) for accuracy of tumour image registration and projected ablation volume overlap in patients undergoing percutaneous PET/CT-guided tumour-ablation procedures under general anaesthesia. MATERIALS AND METHODS: Eight patients underwent 12 PET/CT-guided tumour-ablation procedures to treat 20 tumours in the lung, liver, or adrenal gland. Using breath-hold PET/CT, the centre of the tumour was marked on each PET and CT acquisition by four readers to assess two- (2D) and three-dimensional (3D) spatial misregistration. Overlap of PET and CT projected ablation volumes were compared using the Dice similarity coefficient (DSC). Interobserver differences were assessed with repeated measure analysis of variance (ANOVA). Technical success and local progression rates were noted. RESULTS: Mean tumour 2D PET/CT misregistrations were 1.02 mm (range 0.01-5.02), 1.89 (0.03-7.85), and 3.05 (0-10) in the x, y, and z planes. Mean 3D misregistration was 4.4 mm (0.36-10.74). Mean projected PET/CT ablation volume DSC was 0.72 (±0.19). No significant interobserver differences in 3D misregistration (p=0.73) or DSC (p=0.54) were observed. Technical success of ablations was 100%; one (5.3%) of 19 tumours progressed. CONCLUSION: Accurate spatial registration of tumours and substantial overlap of projected ablation volumes are achievable when comparing PET and CT acquisitions from single-breath-hold PET/CT. The results suggest that tumours visible only at PET could be accurately targeted and ablated using this technique.


Asunto(s)
Artefactos , Contencion de la Respiración , Neoplasias/diagnóstico por imagen , Neoplasias/cirugía , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Cirugía Asistida por Computador/métodos , Adulto , Anciano , Anestesia General , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimiento (Física) , Reproducibilidad de los Resultados , Mecánica Respiratoria , Sensibilidad y Especificidad , Técnica de Sustracción , Resultado del Tratamiento
3.
AJNR Am J Neuroradiol ; 40(5): 878-884, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31023663

RESUMEN

BACKGROUND AND PURPOSE: Intravoxel incoherent motion imaging, which simultaneously measures diffusion and perfusion parameters, is promising for brain tumor grading. However, intravoxel incoherent motion imaging has not been tested in children. The purpose of this study was to evaluate the correlation between intravoxel incoherent motion parameters and histology to assess the accuracy of intravoxel incoherent motion imaging for pediatric intracranial tumor grading. MATERIALS AND METHODS: Between April 2013 and September 2015, 17 children (11 boys, 6 girls; 2 months to 15 years of age) with intracranial tumors were included in this retrospective study. Intravoxel incoherent motion parameters were fitted using 13 b-values for a biexponential model. The perfusion-free diffusion coefficient, pseudodiffusion coefficient, and perfusion fraction were measured in high- and low-grade tumors. These intravoxel incoherent motion parameters and the ADC were compared using the unpaired t test. The correlations between the intravoxel incoherent motion parameters and microvessel density or the MIB-1 index were analyzed using the Spearman correlation test. Receiver operating characteristic analysis was used to evaluate diagnostic performance. RESULTS: The perfusion-free diffusion coefficient and ADC were lower in high-grade than in low-grade tumors (perfusion-free diffusion coefficient, 0.85 ± 0.40 versus 1.53 ± 0.21 × 10-3 mm2/s, P < .001; ADC, 1.04 ± 0.33 versus 1.60 ± 0.21 × 10-3 mm2/s, P < .001). The pseudodiffusion coefficient showed no difference between the groups. The perfusion fraction was higher in high-grade than in low-grade tumors (21.7 ± 8.2% versus 7.6 ± 4.3%, P < .001). Receiver operating characteristic analysis found that the combined perfusion-free diffusion coefficient and perfusion fraction had the best diagnostic performance for tumor differentiation (area under the curve = 0.986). CONCLUSIONS: Intravoxel incoherent motion imaging reflects tumor histology and may be a helpful, noninvasive method for pediatric intracranial tumor grading.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Imagen de Difusión por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador/métodos , Neuroimagen/métodos , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Movimiento (Física) , Clasificación del Tumor/métodos , Estudios Retrospectivos
4.
Diagn Interv Imaging ; 100(7-8): 411-419, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30948344

RESUMEN

PURPOSE: The purpose of this study was to identify magnetic resonance imaging (MRI) features that are associated with telomerase reverse transcriptase promoter mutation (TERTm) in glioblastoma. MATERIALS AND METHODS: A total of 112 patients with glioblastoma who had MRI at 1.5- or 3.0-T were retrospectively included. There were 43 patients with glioblastoma with wild-type TERT (TERTw) (22 men, 21 women; mean age, 47±25 [SD] years; age range: 3-84 years) and 69 patients with glioblastoma with TERTm (34 men, 35 women; mean age 64±11 [SD] years; age range, 41--85 years). The feature vectors consist of 11 input units for two clinical parameters (age and gender) and nine MRI characteristics (tumor location, subventricular extension, cortical extension, multiplicity, enhancing volume, necrosis volume, the percentage of necrosis volume, minimum apparent diffusion coefficient [ADC] and normalized ADC). First, the diagnostic performance using univariate and multivariate logistic regression analyses was evaluated. Second, the cross-validation of the support vector machine (SVM) was performed by using leave-one-out method with 43 TERTw and 69 TERTm to evaluate the diagnostic performance. In addition, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for the differentiation between TERTw and TERTm were compared between logistic regression analysis and SVM. RESULTS: With multivariate analysis, the percentage of necrosis volume and age were significantly greater in TERTm glioblastoma than in TERTw glioblastoma. SVM allowed discriminating between TERTw glioblastoma and TERTm glioblastoma with sensitivity, specificity, PPV, NPV, and accuracy of 85.7% [60/70; 95% confidence interval (CI): 75.3-92.9%], 54.8% (23/42; 95% CI: 38.7-70.2%), 75.9% (60/79; 95% CI: 69.1-81.7%), 69.7% (23/33; 95% CI: 54.9-81.3%) and 74.1% (83/112; 95% CI: 65.0-81.9%), respectively. CONCLUSION: The percentage of necrosis volume and age may surrogate for predicting TERT mutation status in glioblastoma.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Glioblastoma/diagnóstico por imagen , Imagen por Resonancia Magnética , Mutación , Regiones Promotoras Genéticas , Telomerasa , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Niño , Preescolar , Medios de Contraste , Femenino , Glioblastoma/genética , Glioblastoma/patología , Humanos , Isocitrato Deshidrogenasa/genética , Masculino , Persona de Mediana Edad , Análisis Multivariante , Necrosis , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Máquina de Vectores de Soporte , Adulto Joven
5.
Water Sci Technol ; 58(5): 1055-60, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18824804

RESUMEN

The pollution of tap water and rain water with formaldehyde in Toyama Pref., Japan was investigated by means of a simple, rapid and cost-effective visual colorimetry developed by us. The levels of formaldehyde in three tap waters from different sources of dams on mountainside and a well-water pumped in urban area in Toyama Pref. were lower than 0.01 mg L(-1) that was the detection limit of the colorimetry. On the other hand, rain waters were seriously polluted with formaldehyde. Rain waters were sampled from three different sites (urban area, top of hill and industrial area) in Toyama Pref. from autumn to winter in 2006. The levels of formaldehyde in the rain waters ranged from 0.07 to 0.30 mg L(-1). The analytical results by the visual colorimetry were in good agreement with those obtained by GC-MS method. It was confirmed that the colorimetry is excellent for practical use for the determination of formaldehyde. It must be concerned about the pollution of rainwater with formaldehyde, when rain water is applied for tap water and miscellaneous purpose.


Asunto(s)
Colorimetría/métodos , Formaldehído/análisis , Lluvia/química , Abastecimiento de Agua/análisis , Geografía , Japón , Contaminantes Químicos del Agua/análisis
6.
Comput Aided Surg ; 12(1): 15-24, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17364655

RESUMEN

In prostate cancer treatment, there is a move toward targeted interventions for biopsy and therapy, which has precipitated the need for precise image-guided methods for needle placement. This paper describes an integrated system for planning and performing percutaneous procedures with robotic assistance under MRI guidance. A graphical planning interface allows the physician to specify the set of desired needle trajectories, based on anatomical structures and lesions observed in the patient's registered pre-operative and pre-procedural MR images, immediately prior to the intervention in an open-bore MRI scanner. All image-space coordinates are automatically computed, and are used to position a needle guide by means of an MRI-compatible robotic manipulator, thus avoiding the limitations of the traditional fixed needle template. Automatic alignment of real-time intra-operative images aids visualization of the needle as it is manually inserted through the guide. Results from in-scanner phantom experiments are provided.


Asunto(s)
Biopsia con Aguja , Imagen por Resonancia Magnética/métodos , Neoplasias de la Próstata/diagnóstico , Robótica , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Neuronavegación
7.
Stud Health Technol Inform ; 125: 433-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17377318

RESUMEN

In this paper a comprehensive framework for pre-operative planning, procedural skill training, and intraoperative navigation is presented. The goal of this system is to integrate surgical simulation with surgical planning in order to improve the individual treatment of patients. Various surgical approaches and new, more complex procedures can be assessed using a safe and objective platform that will allow the physicians to explore and discuss possible risks and benefits prior to the intervention. A simulation environment extends the pre-operative planning in a natural way, as it allows for direct evaluation of the surgical approach envisioned for each case. In addition, by providing intraoperative navigation based on this simulation, surgeons can carry out the previously optimized plan with higher precision and greater confidence.


Asunto(s)
Modelos Anatómicos , Ventriculostomía/instrumentación , Endoscopios , Cirugía General/organización & administración , Humanos , Maniquíes , Errores Médicos/prevención & control , Garantía de la Calidad de Atención de Salud , Suiza
8.
Stud Health Technol Inform ; 119: 120-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16404029

RESUMEN

This work explores an image-based approach for localizing needles during MRI-guided interventions, for the purpose of tracking and navigation. Susceptibility artifacts for several needles of varying thickness were imaged, in phantoms, using a 3 tesla MRI system, under a variety of conditions. The relationship between the true needle positions and the locations of artifacts within the images, determined both by manual and automatic segmentation methods, have been quantified and are presented here.


Asunto(s)
Artefactos , Imagen por Resonancia Magnética , Agujas , Estados Unidos
9.
Stud Health Technol Inform ; 119: 126-31, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16404030

RESUMEN

This work describes an integrated system for planning and performing percutaneous procedures-such as prostate biopsy-with robotic assistance under MRI-guidance. The physician interacts with a planning interface in order to specify the set of desired needle trajectories, based on anatomical structures and lesions observed in the patient's MR images. All image-space coordinates are automatically computed, and used to position a needle guide by means of an MRI-compatible robotic manipulator, thus avoiding the limitations of the traditional fixed needle template. Direct control of real-time imaging aids visualization of the needle as it is manually inserted through the guide. Results from in-scanner phantom experiments are provided.


Asunto(s)
Biopsia con Aguja , Imagen por Resonancia Magnética , Robótica/instrumentación , Sistemas de Computación , Humanos , Masculino , Neoplasias de la Próstata/diagnóstico
10.
Biochim Biophys Acta ; 1483(1): 101-10, 2000 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-10601699

RESUMEN

We have noted that n-3 fatty acid-rich oils, such as fish oil, perilla oil and flaxseed oil as well as ethyl docosahexaenoate (DHA) prolonged the survival time of stroke-prone spontaneously hypertensive rats (SHRSP) rats by approximately 10% as compared with linoleate (n-6)-rich safflower oil. Rapeseed oil with a relatively low n-6/n-3 ratio unusually shortened the survival time by approximately 40%, suggesting the presence of minor components unfavorable to SHRSP rats. This study examined the effects of dietary oils and DHA on renal injury and gene expression related to renal injury in SHRSP rats. Rats fed rapeseed oil- and safflower oil-supplemented diets developed more severe proteinuria than those fed soybean oil-supplemented diet used as a control, but there were no significant differences in blood pressure. In contrast, the DHA-supplemented diet inhibited the development of proteinuria and suppressed hypertension. The mRNA levels for renal TGF-beta, fibronectin and renin were higher in the rapeseed oil and safflower oil groups after 9 weeks of feeding of the experimental diet than in the soybean oil and DHA groups. The fatty acid composition of kidney phospholipids was markedly affected by these diets. These results indicate that the renal injury observed in the groups fed safflower oil with a high n-6/n-3 ratio and rapeseed oil with presumed minor components is accompanied by increased expression of the TGF-beta, renin and fibronectin genes, and that dietary DHA suppresses renal injury and gene expression as compared with soybean oil.


Asunto(s)
Grasas Insaturadas en la Dieta/farmacología , Grasas de la Dieta/farmacología , Ácidos Docosahexaenoicos/farmacología , Riñón/efectos de los fármacos , Accidente Cerebrovascular/fisiopatología , Animales , Presión Sanguínea , Ácidos Grasos/análisis , Ácidos Grasos Monoinsaturados , Fibronectinas/genética , Fibronectinas/metabolismo , Expresión Génica , Frecuencia Cardíaca , Riñón/fisiopatología , Fosfolípidos/metabolismo , Aceites de Plantas/farmacología , ARN Mensajero/metabolismo , Aceite de Brassica napus , Ratas , Ratas Endogámicas SHR , Renina/genética , Renina/metabolismo , Aceite de Cártamo/farmacología , Aceite de Soja/farmacología , Factores de Tiempo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
11.
Neurobiol Aging ; 11(2): 139-50, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2348902

RESUMEN

Two experiments were performed. In the first, a 20 min conditioned emotional response (CER) paradigm was used to compare the neurochemical, endocrine and immunological responses to stress of 7- and 22-month-old Fischer 344 (F344) male rats. In the second, corticosterone levels 20 min following ether stress, and regional brain type I and II corticosterone receptor densities were examined using 7- and 17.5-month-old F344 male rats. Dopamine (DA) metabolism in old nonstressed rats was significantly reduced in the medial frontal cortex, neostriatum, nucleus accumbens and hypothalamus, but not in the amygdala. The CER procedure, nevertheless, increased medial frontal cortical, nucleus accumbens and amygdaloid DA turnover in both the young and old rats. The young and old nonstressed rats did not evidence differences in norepinephrine (NE) and serotonin (5-HT) concentrations. However, stress resulted in a decrease in medial frontal cortical 5-hydroxyindoleacetic acid (5-HIAA) and hypothalamic 5-HT levels in old but not in young animals. These observations suggest age-related differences in the response of central NE and 5-HT systems to stress. Ether and the CER procedure led to exaggerated corticosterone responses in the old rats (17.5 and 22 month, respectively). Hippocampal type I but not type II corticosterone receptors were decreased by 47% in the 17.5-month-old rats. Thus, age-related changes in hippocampal corticosterone receptor types do not occur in unison, and the exacerbated corticosterone response to stress precedes the reported down-regulation of hippocampal type II corticosterone receptors in aged rats. Age-related changes were not observed in the concentrations of corticosterone receptors in other brain regions, or in the prolactin response to stress. The old rats, however, evidenced a reduction in the availability of the renin substrate, angiotensinogen, and in stress-induced renin secretion. Immune function was impaired in the old nonstressed rats, and further compromised by exposure to the CER procedure. In comparison to the young control rats, the old nonstressed rats showed an increased percentage of splenic large granular lymphocytes, reduced splenic natural killer cytotoxicity, and impaired Con-A-stimulated splenic T lymphocyte proliferation. Reductions in T splenic cell proliferation and natural killer cytotoxicity were observed in the young rats subjected to the CER paradigm, but not to the same extent as in the old rats. These observations indicate that aging male F344 rats evidence major alterations in basal central monoamine, endocrine and immune functions, and an increased sensitivity of these systems to stress.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Glándulas Endocrinas/fisiología , Sistema Inmunológico/fisiología , Estrés Fisiológico/metabolismo , Animales , Masculino , Neuroquímica , Ratas , Ratas Endogámicas F344
12.
FEBS Lett ; 425(1): 112-6, 1998 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-9541017

RESUMEN

The virus-induced activation of interferon alpha/beta (IFN-alpha/beta) gene transcription is essential for host defense. The IFN-beta promoter is controlled primarily by the virus-inducible enhancer elements, the IRF-Es. Here we show that IRF-3, an IRF family transcription factor, translocates to the nucleus from the cytoplasm upon virus infection in NIH/3T3 cells. The nuclear IRF-3 is phosphorylated, interacts with the co-activators CBP/p300, and binds specifically to the IFN-beta IRF-E. Furthermore, overexpression of IRF-3 causes a marked increase in virus-induced IFN-beta mRNA expression. Thus, IRF-3 is a candidate transcription factor mediating the activation of the IFN-beta gene.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Regulación de la Expresión Génica/fisiología , Interferón beta/genética , Transactivadores , Factores de Transcripción/fisiología , Células 3T3 , Animales , Transporte Biológico , Proteínas de Unión al ADN/metabolismo , Proteína p300 Asociada a E1A , Factor 3 Regulador del Interferón , Ratones , Proteínas Nucleares/metabolismo , Fosforilación , Factores de Transcripción/metabolismo
13.
FEBS Lett ; 441(1): 106-10, 1998 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9877175

RESUMEN

The interferon regulatory factor (IRF) family of transcription factors regulate the interferon (IFN) system, among which IRF-3 is involved in the virus-induced IFN-beta gene expression. Here we show that another member IRF-7 is critical for the IFN-alpha gene induction. Unlike the IRF-3 gene, the IRF-7 gene is induced by IFNs through activation of the ISGF3 transcription factor, and IRF-7 undergoes virus-induced nuclear translocation. In cells lacking p48, an essential component of IFN stimulated gene factor 3 (ISGF3), ectopic expression of IRF-7 but not IRF-3 can rescue the deficiency to induce IFN-alpha genes. These results indicate that IRF-7 is a key factor in the positive feedback regulation of IFN-alpha/beta production.


Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Interferón Tipo I/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Animales , Células Cultivadas , Proteínas de Unión al ADN/química , Retroalimentación , Vectores Genéticos , Factor 7 Regulador del Interferón , Interferón Tipo I/biosíntesis , Factor 3 de Genes Estimulados por el Interferón , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón , Ratones , Ratones Noqueados , Modelos Genéticos , Datos de Secuencia Molecular , Retroviridae , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Factores de Transcripción/química , Activación Transcripcional , Transfección
14.
Neuroscience ; 93(1): 237-41, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10430487

RESUMEN

Wistar rats were fed a fish oil-deficient diet through three generations. The young (five-week-old) male rats of the third generation were randomly divided into two groups. Over 10 weeks, one group was perorally administered docosahexaenoic acid dissolved in 5% gum Arabic solution at 300 mg/kg/day; the other group received a similar volume of vehicle alone. Five weeks after starting the administration, the rats were tested for learning ability related to two types of memory, reference memory and working memory, with the partially (four of eight) baited eight-arm radial maze. Reference memory is information that should be retained until the next trial. Working memory is information that disappears in a short time. Entries into unbaited arms and repeated entries into visited arms were defined as reference memory errors and working memory errors, respectively. Docosahexaenoic acid administration over 10 weeks significantly reduced the number of reference memory errors, without affecting the number of working memory errors, and significantly increased the docosahexaenoic acid content and the docosahexaenoic acid/arachidonic acid ratio in both the hippocampus and the cerebral cortex. In addition, the ratio demonstrated a significantly negative correlation with the number of reference memory errors. These results suggest that chronic administration of docosahexaenoic acid is conducive to the improvement of reference memory-related learning ability, and that the docosahexaenoic acid/arachidonic acid ratio in the hippocampus or the cerebral cortex, or both, may be an indicator of learning ability.


Asunto(s)
Ácidos Docosahexaenoicos/farmacología , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Animales , Ácido Araquidónico/metabolismo , Química Encefálica/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Ácidos Grasos/sangre , Ácidos Grasos/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Peróxidos Lipídicos/sangre , Peróxidos Lipídicos/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratas , Ratas Wistar
15.
Antiviral Res ; 15(1): 41-9, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2035999

RESUMEN

Commercial lignins suppressed the growth of influenza A virus infecting MDCK cells, and the RNA-dependent RNA synthesis, as efficiently as the high-molecular weight fractions extracted from pine cone of Pinus parviflora Sieb. et Zucc. The anti-influenza A virus activity of both pine cone extract and commercial alkali-lignin was considerably reduced by treatment with sodium chlorite, but was not affected by sulfuric acid or trifluoroacetic acid. The degraded components of lignin, various synthesized polyphenols unrelated to lignin, and natural and chemically modified glucans, were not appreciably inhibitory. The data suggest that the polymerized phenolic structure of lignified materials is responsible for the anti-influenza A virus activity.


Asunto(s)
Antivirales/farmacología , Lignina/farmacología , Orthomyxoviridae/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Antivirales/química , Células Cultivadas/microbiología , Cloruros/farmacología , Hidrólisis , Lignina/química , Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Extractos Vegetales/química , ARN Viral/biosíntesis , Ácidos Sulfúricos/farmacología , Ácido Trifluoroacético/farmacología
16.
Artículo en Inglés | MEDLINE | ID: mdl-10841036

RESUMEN

Mice were fed a diet supplemented either with beef tallow (BT), BT plus ethyl eicosapentaenoate (EPA) or BT plus ethyl docosahexaenoate (DHA) for 9 weeks. EPA and DHA supplementation increased the content of the respective fatty acid in spleen leukocyte lipids, which was associated with the reduction in the arachidonate content. IL-1beta mRNA induction upon lipopolysaccharide (LPS) stimulation in spleen leukocytes in the DHA diet group was significantly lower than in the BT diet group, but the EPA diet was without any significant effect. The amount of prostaglandin E2 (PGE2) released from LPS-stimulated spleen leukocytes was significantly lower in both the EPA and DHA groups than in the BT group. Thus, dietary EPA and DHA inhibited arachidonate metabolism similarly but had different effects on IL-1beta mRNA induction in mouse spleen leukocytes.


Asunto(s)
Ácidos Docosahexaenoicos/farmacología , Ácido Eicosapentaenoico/farmacología , Inmunosupresores/farmacología , Interleucina-1/biosíntesis , Interleucina-1/genética , Leucocitos/metabolismo , Lipopolisacáridos/farmacología , ARN Mensajero/biosíntesis , Bazo/metabolismo , Animales , Dinoprostona/biosíntesis , Ácidos Grasos/análisis , Femenino , Interleucina-1/antagonistas & inhibidores , Leucocitos/efectos de los fármacos , Lipopolisacáridos/antagonistas & inhibidores , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/antagonistas & inhibidores , Bazo/efectos de los fármacos
17.
Neurosci Lett ; 120(1): 101-4, 1990 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-1981384

RESUMEN

Bilateral infusion of DL-2-amino-5-phosphonovalerate (DL-APV) (which is a competitive antagonist for N-methyl-D-aspartate (NMDA) receptor) into the medial frontal cortex of conscious rats increased the amount of 3,4-dihydroxyphenylacetic acid (DOPAC) and the DOPAC/dopamine (DA) ratio in the cortical area. Moreover, intra-prefrontal injection of DL-APV, D-APV, DL-2-amino-7-phosphonoheptanoate and 3-[(+/-])-2-carboxypiperazin-4-yl]-propyl-1-phosphonate (which are selective NMDA receptor antagonists), but not the L-isomer of APV and gamma-glutamyl-aminomethyl sulphonate (a relative antagonist for non-NMDA receptors), facilitated prefrontal DA utilization in a NMDA-reversible manner. These findings suggest that NMDA-type excitatory amino acid receptors may be involved in a tonic inhibitory regulation of dopaminergic transmission in the medial frontal cortex in vivo.


Asunto(s)
Corteza Cerebral/fisiología , Dopamina/metabolismo , N-Metilaspartato/farmacología , Receptores de N-Metil-D-Aspartato/fisiología , 2-Amino-5-fosfonovalerato/administración & dosificación , 2-Amino-5-fosfonovalerato/farmacología , Ácido 3,4-Dihidroxifenilacético/metabolismo , Animales , Corteza Cerebral/efectos de los fármacos , Glutamina/análogos & derivados , Glutamina/farmacología , Infusiones Parenterales , Isomerismo , Masculino , Metiltirosinas/farmacología , N-Metilaspartato/administración & dosificación , Piperazinas/farmacología , Ratas , Ratas Endogámicas , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Tirosina 3-Monooxigenasa/antagonistas & inhibidores , alfa-Metiltirosina
18.
Free Radic Res ; 30(3): 199-205, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10711790

RESUMEN

Weaning mice were fed a diet supplemented with beef tallow (BT) or BT plus docosahexaenoic acid (DHA) containing 100 mg alpha-tocopherol/kg (alpha-Toc100) or 500 mg alpha-tocopherol/kg (alpha-Toc500) for 4 wk to modify membrane fatty acid unsaturation, and then were administered ferric nitrilotriacetate (Fe-NTA). The mortality caused by Fe-NTA was higher in the group fed the DHA (alpha-Toc100) diet than in the BT diet groups but the DHA (alpha-Toc500) diet suppressed this increase. Serum and kidney alpha-tocopherol contents were slightly influenced by the dietary fatty acids but not significantly. These results indicate that the increased unsaturation of tissue lipids enhances oxidative damage induced by Fe-NTA in mice fed DHA (alpha-Toc100) but not when additional alpha-tocopherol is supplemented. The apparent discrepancy between the observed enhancement by dietary DHA of oxidative damage and the beneficial effects of dietary DHA on the so-called free radical diseases is discussed in terms of strong bolus oxidative stress and moderate chronic oxidative stress.


Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Grasas Insaturadas en la Dieta/toxicidad , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/toxicidad , Compuestos Férricos/toxicidad , Ácido Nitrilotriacético/análogos & derivados , Vitamina E/administración & dosificación , Animales , Interacciones Farmacológicas , Ácidos Grasos/análisis , Femenino , Compuestos Férricos/administración & dosificación , Riñón/efectos de los fármacos , Riñón/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Ratones , Ratones Endogámicos ICR , Ácido Nitrilotriacético/administración & dosificación , Ácido Nitrilotriacético/toxicidad , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Fosfolípidos/química , Fosfolípidos/metabolismo , Vitamina E/sangre , Vitamina E/metabolismo
19.
J Biomed Opt ; 3(3): 304-11, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23015084

RESUMEN

Hardware and software for a customized system to use magnetic resonance imaging (MRI) to noninvasively monitor laser-induced interstitial thermal therapy of brain tumors are reported. An open-configuration interventional MRI unit was used to guide optical fiber placement and monitor the deposition of laser energy into the targeted lesion. T1-weighted fast spin echo and gradient echo images were used to monitor the laser tissue interaction. The images were transferred from the MRI scanner to a customized research workstation and were processed intraoperatively. Newly developed software enabled rapid (27-221 ms) availability of calculated images. A case report is given showing images which reveal the laser-tissue interaction. The system design is feasible for on-line monitoring of interstitial laser therapy. © 1998 Society of Photo-Optical Instrumentation Engineers.

20.
Med Phys ; 28(12): 2551-60, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11797960

RESUMEN

In this report we evaluate an image registration technique that can improve the information content of intraoperative image data by deformable matching of preoperative images. In this study, pretreatment 1.5 tesla (T) magnetic resonance (MR) images of the prostate are registered with 0.5 T intraoperative images. The method involves rigid and nonrigid registration using biomechanical finite element modeling. Preoperative 1.5 T MR imaging is conducted with the patient supine, using an endorectal coil, while intraoperatively, the patient is in the lithotomy position with a rectal obturator in place. We have previously observed that these changes in patient position and rectal filling produce a shape change in the prostate. The registration of 1.5 T preoperative images depicting the prostate substructure [namely central gland (CG) and peripheral zone (PZ)] to 0.5 T intraoperative MR images using this method can facilitate the segmentation of the substructure of the gland for radiation treatment planning. After creating and validating a dataset of manually segmented glands from images obtained in ten sequential MR-guided brachytherapy cases, we conducted a set of experiments to assess our hypothesis that the proposed registration system can significantly improve the quality of matching of the total gland (TG), CG, and PZ. The results showed that the method statistically-significantly improves the quality of match (compared to rigid registration), raising the Dice similarity coefficient (DSC) from prematched coefficients of 0.81, 0.78, and 0.59 for TG, CG, and PZ, respectively, to 0.94, 0.86, and 0.76. A point-based measure of registration agreement was also improved by the deformable registration. CG and PZ volumes are not changed by the registration, indicating that the method maintains the biomechanical topology of the prostate. Although this strategy was tested for MRI-guided brachytherapy, the preliminary results from these experiments suggest that it may be applied to other settings such as transrectal ultrasound-guided therapy, where the integration of preoperative MRI may have a significant impact upon treatment planning and guidance.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Fenómenos Biofísicos , Biofisica , Braquiterapia/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Próstata/patología , Reproducibilidad de los Resultados
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