RESUMEN
Metal-organic framework (MOF) activation is crucial for the use of MOFs in several applications and solvent-exchange process is a necessary step in many activation methods. In this contribution, we have explored in situ MOF monolayer film formation at the air-water interface. Nanoparticles (NPs) of the Al trimesate MIL-96(Al) retain chloroform into their micropores, which considerably diminishes the CO2 adsorption capacity of MOF films. However, a solvent-exchange process between chloroform and water increases CO2 film adsorption capacity by 30%. Total Reflection X-Ray Fluorescence (TRXF) allows studying the kinetics of this process at the air-water interface, that strongly depends on the NP size. The conclusions derived from in situ studies allow optimizing the ex situ activation procedure of MIL-96(Al) films deposited onto quartz crystal microbalance (QCM) substrates in order to maximize CO2 and methanol adsorption.
RESUMEN
N-methyl-D-aspartate receptor encephalitis is an autoimmune encephalitis relationated or not with a neoplasm. Although its incidence is unknown, probably remains underdiagnosed. Epidemiological studies place it as the second cause of immune-mediated encephalitis and the first in patients aged less of 30 years. It shows neuropsychiatric symptoms and autonomic instability. After diagnosis, based on the detection of antibodies in serum or cerebrospinal fluid, an occult malignancy must be investigated. While increasing number of cases have been diagnosed and the important role of this receptor in general anesthesia mechanisms, the interaction of the disease with anesthetic agents and perioperative stress is unknown. We describe the case of a patient with encephalitis associated to ovarian teratoma that underwent gynaecological laparoscopy.
Asunto(s)
Anestesia Intravenosa , Encefalitis Antirreceptor N-Metil-D-Aspartato/etiología , Neoplasias Ováricas/complicaciones , Ovariectomía , Teratoma/complicaciones , Adulto , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico , Encefalitis Antirreceptor N-Metil-D-Aspartato/tratamiento farmacológico , Encefalitis Antirreceptor N-Metil-D-Aspartato/psicología , Trastornos de la Conciencia/etiología , Contraindicaciones , Errores Diagnósticos , Epilepsia Tónico-Clónica/etiología , Femenino , Fentanilo , Humanos , Ketamina , Trastornos Mentales/diagnóstico , Trastornos Mentales/etiología , Óxido Nitroso , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/cirugía , Propofol , Trastornos Psicóticos/diagnóstico , Rituximab/uso terapéutico , Teratoma/inmunología , Teratoma/cirugíaRESUMEN
Objetivos: analizar la capacidad de predicción clínica respecto al diagnóstico de gripe A nH1N1 de los síntomas que presentan los pacientes ambulatorios registrados en la base de datos de la Red Centinela de Aragón (RCA). Comparar la casuística ambulatoria con los pacientes ingresados durante la epidemia de gripe A nH1N1 (2009-2010). Pacientes y métodos: estudio descriptivo retrospectivo de los pacientes que cumplían los criterios epidemiológicos de definición de caso, en los que de manera aleatoria se les realizó reacción en cadena de la polimerasa en tiempo real (PCR-RT) de gripe A nH1N1, así como de los pacientes ingresados en el hospital de tercer nivel de referencia. Comparación de las características epidemiológicas y clínicas entre los pacientes ambulatorios y hospitalarios. Resultados: de los pacientes registrados por la RCA no se encontraron diferencias clínicas entre los niños con frotis (PCR-RT) positivo o negativo para el virus gripal nH1N1, por lo que no se ha podido encontrar un conjunto de síntomas que sean predictores de tener un frotis positivo con la PCR-RT. Los pacientes hospitalizados tenían menor edad que los de la RCA, así como mayor porcentaje de patología de base y comorbilidad asociada. Conclusión: según los datos analizados, la epidemia de gripe A se comportó como una enfermedad benigna, de sintomatología similar a la gripe estacional. Tan solo el hecho de encontrar clínica gripal en una semana epidemiológica de alta incidencia (semanas 43-48) resultaron moderadamente predictores de infección por gripe A(AU)
Objectives: to analyze the prediction's capacity of clinical symptoms to diagnose nH1N1 Influenza in outpatients who were chosen by Aragon's Sentinel surveillance Network. To compare outpatients with hospitalized cases during influenza A virus pandemic (2009-2010). Methods: retrospective study of a randomized group of patients with symptoms of influenza who had laboratory-confirmation by PCR-RT and of all patients admitted to the reference hospital of Aragon. Comparison of epidemiological and clinical characteristics in outpatients and between outpatients and hospital cases. Results: there were no clinical differences between the laboratory-confirmed by PCR-RT cases and the other outpatients, so it was not possible to find defining symptoms of infection. Hospitalized patients were younger, with higher percentage of underlying disease and comorbidity. Conclusions: the epidemic of influenza A behaved as a benign disease, symptoms were similar to seasonal influenza. The clinical finding of having influenza symptoms in a high incidence week (weeks 43-48) was moderately predictive of influenza A infection(AU)
Asunto(s)
Humanos , Masculino , Femenino , Niño , Epidemias/prevención & control , /inmunología , /patogenicidad , Atención Primaria de Salud/métodos , Atención Primaria de Salud/tendencias , Atención Ambulatoria/organización & administración , Sistemas de Información en Atención Ambulatoria/normas , Gripe Humana/epidemiología , Monitoreo Epidemiológico/organización & administración , Monitoreo Epidemiológico/normas , Atención Primaria de Salud/ética , Atención Primaria de Salud/normas , Monitoreo EpidemiológicoRESUMEN
CASE REPORT: We described the follow up of a patient with diabetes mellitus type 2 who had a macular pattern dystrophy and bilateral neurosensory hearing loss. Electrophysiological studies revealed abnormal pattern electroretinography and impaired electro-oculogram responses. DISCUSSION: Maternally Inherited Diabetes, neurosensory Deafness and generally macular pattern distrophy (MIDD syndrome), is a rare mitochondrial disease, responsible for approximately 0.5 to 2.8% of diabetes mellitus.
Asunto(s)
Sordera/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Enfermedades Mitocondriales/complicaciones , Sordera/genética , Diabetes Mellitus Tipo 2/genética , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Caso clínico: Se describe el seguimiento de unpaciente diabético tipo 2 con una degeneraciónmacular en patrón y sordera neurosensorial bilateral.En la electrofisiología mostraba un electrorretinograma(ERG) patrón anormal y un electrooculograma(EOG) disminuido.Discusión: La presencia de diabetes de herenciamaterna y sordera neurosensorial, a los que suelesumarse una distrofia macular en patrón, constituyenel síndrome MIDD (Maternally Inherited Diabetesand Deafness), una rara enfermedad mitocondrialresponsable de un 0,5% a 2,8% de los diabéticos(AU)
Case report: We described the follow up of apatient with diabetes mellitus type 2 who had amacular pattern dystrophy and bilateral neurosensoryhearing loss. Electrophysiological studiesrevealed abnormal pattern electroretinography andimpaired electro-oculogram responses.Discussion: Maternally Inherited Diabetes, neurosensoryDeafness and generally macular patterndistrophy (MIDD syndrome), is a rare mitochondrialdisease, responsible for approximately 0.5 to2.8% of diabetes mellitus(AU)
Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Diabetes Mellitus Tipo 2 , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etiología , Diabetes Mellitus Tipo 2/terapia , Sordera , ADN , Enfermedades Mitocondriales , Distrofias Hereditarias de la CórneaRESUMEN
Eclampsia is a complication of preeclampsia and is characterized by the appearance of grand mal seizures and/or coma, in the absence of any other neurological abnormalities. Neither focal neurological deficit nor prolonged coma tends to develop following a crisis. Eclampsia should therefore lead us to consider other clinical entities that may require special treatment. We report the case of a pregnant woman who presented total bilateral loss of vision following a grand mal seizure. The patient was subsequently diagnosed with reversible posterior leukoencephalopathy syndrome, which has clinical and radiologic manifestations linked to several causes, such as hypertensive encephalopathy, eclampsia, kidney failure, and immunosuppressant therapy. The syndrome involves headache, altered states of consciousness, changes in vision (including blindness), and seizures; these symptoms generally coincide with a rapid increase in blood pressure. Diagnosis requires neuroimaging, and the typical finding is edema in the posterior zones of the brain hemispheres. The most widely accepted hypothesis concerning the pathophysiologic mechanism underlying this syndrome is failure of cerebral autoregulation with development of vasogenic edema. The prognosis is good and the alterations usually resolve completely with appropriate treatment, which is the same as for the management of eclampsia, with strict monitoring of blood pressure.
Asunto(s)
Síndrome de Leucoencefalopatía Posterior/diagnóstico , Adolescente , Ceguera/etiología , Eclampsia/etiología , Femenino , Humanos , Síndrome de Leucoencefalopatía Posterior/complicaciones , EmbarazoRESUMEN
Negative pressure pulmonary edema is a complication, described since 1977, caused by upper airway obstruction in both children and adults. Although its aetiopathogeny is multifactorial, especially outstanding is excessive negative intrathoracic pressure caused by the forced spontaneous inspiration of a patient against a closed glottis, that causes high arteriole and capillary fluid pressures that favor transudation into the alveolar space The resulting pulmonary edema can appear a few minutes after the obstruction of the airway or in a deferred way after several hours. The clinical manifestations are potentially serious, but normally respond well to treatment with supplemental oxygen, positive pressure mechanical ventilation and diuretics. Diagnostic suspicion is important for acting promptly. We report three clinical cases with acute negative pressure pulmonary edema.
Asunto(s)
Edema Pulmonar , Adolescente , Adulto , Obstrucción de las Vías Aéreas/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Presión , Edema Pulmonar/diagnóstico , Edema Pulmonar/etiología , Edema Pulmonar/terapiaRESUMEN
The low dose rate CDC-type miniature cylindrical 137Cs sources are available, with one or three active beads, for use in source trains in automatic and manual afterloading systems for gynecological brachytherapy. Absolute dose rate distributions in water have been calculated around these sources using the Monte Carlo GEANT3 code and they are presented as conventional two-dimensional Cartesian lookup tables. The AAPM Task Group 43 formalism for dose calculation has been also applied. The dose rate constant obtained for the one bead source is lambda = 1.113 +/- 0.003cGyh(-1) U(-1), and the value for the three bead source is A= 1.103 +/- 0.003cGyh(-1) U(-1). Finally, for the treatment planning systems based on Sievert-type algorithms, the attenuation coefficients that best reproduce Monte Carlo dose rate distribution are given.
Asunto(s)
Braquiterapia/instrumentación , Braquiterapia/métodos , Radiometría/métodos , Aire , Algoritmos , Método de Montecarlo , Radiometría/normas , Planificación de la Radioterapia Asistida por ComputadorRESUMEN
Basic dosimetric data for the Walstam CDC.K-type low dose rate 137Cs sources in water have been calculated using Monte Carlo techniques. These sources, CDC.K1 -K3 and CDC.K4, are widely used in a range of applicators and moulds for the treatment of intracavitary and superficial cancers. Our purpose is to improve existing data about these sources using the Monte Carlo simulation code GEANT3. Absolute dose rate distributions in water have been calculated around these sources and are presented as conventional 2D Cartesian look-up tables. Also the AAPM Task Group 43 formalism for dose calculation has been applied. The calculated dose rate constant for the CDC.K1-K3 source is A = 1.106 +/- 0.001 cGy h(-1) U(-1), and for the CDC.K4 source, A = 1.092 +/- 0.001 cGy h(-1) U(-1). The anisotropy of the sources are accurately studied and F(r, theta) tables are given. Also phi an(r) factors are presented. The radial dose functions are given as a polynomial fit to the calculated data up to 15 cm. Best-fit values of coefficients suitable for use in Sievert integral calculations have been derived.
Asunto(s)
Radioisótopos de Cesio , Planificación de la Radioterapia Asistida por Computador/métodos , Algoritmos , Anisotropía , Humanos , Modelos Estadísticos , Método de Montecarlo , Radiometría , Programas InformáticosRESUMEN
In this study a complete set of dosimetric data is presented for the high dose rate (HDR) source from Amersham used in the Buchler remote afterloading HDR unit. These data have been calculated by means of the Monte Carlo simulation code GEANT taking into account the detailed geometry of the source. Absolute dose rate distributions in water were calculated around this source and are presented as conventional 2D Cartesian look-up tables. All dosimetric quantities recommended by the AAPM Task Group 43 report have been calculated. Quantities determined are: dose rate constant, radial dose function, anisotropy function, anisotropy factor and anisotropy constant. The dose rate distributions of the Buchler HDR source are compared with those of other HDR sources used in brachytherapy, showing that the differences are large in zones near the long source axis due to oblique filtration. These Monte Carlo simulated data in water can be used for clinical applications.
Asunto(s)
Braquiterapia/instrumentación , Braquiterapia/métodos , Radioisótopos de Iridio , Anisotropía , Diseño de Equipo , Método de Montecarlo , Dosificación RadioterapéuticaRESUMEN
In this study a complete set of dosimetric data for the Plus and 12i Gammamed PDR (pulsed dose rate) 192Ir sources is presented. These data have been calculated using the Monte Carlo simulation code GEANT3. Absolute dose rate distributions in water around these sources were calculated and are presented in form of conventional two dimensional (2D) Cartesian look-up tables. All dosimetric quantities recommended by the AAPM Task Group 43 report have been also calculated. These quantities are dose rate constant, radial dose function, anisotropy function and anisotropy factor. The dose rate distribution of the 12i source was compared with the corresponding data for the microselectron PDR source showing large differences between both sources.
Asunto(s)
Radioisótopos de Iridio/uso terapéutico , Radiometría/métodos , Aire , Anisotropía , Método de Montecarlo , Aceleradores de Partículas , AguaRESUMEN
In this study a complete set of dosimetric data for the GammaMed high dose rate (HDR) 12i and Plus 192Ir sources are presented. These data have been calculated by means of the Monte Carlo simulation code GEANT3. Absolute dose rate distributions in water are presented as conventional two dimensional (2D) Cartesian look-up tables, and in the TG43 formalism.
Asunto(s)
Braquiterapia/instrumentación , Radioisótopos de Iridio/uso terapéutico , Radiometría/métodos , Anisotropía , Fenómenos Biofísicos , Biofisica , Método de Montecarlo , AguaRESUMEN
A 14-year-old boy with a history of congenital cardiopathy is presented. At age 4, a left systemic-to-pulmonary fistula was performed, using a tubular prosthesis to anastomose the left subclavian artery to the left pulmonary artery. Following this procedure, he developed recurrent episodes of hemoptysis, cough, and left upper lobe consolidation. Treatment resulted in clinical but no radiologic resolution. At age 6, a new right systemic-to-pulmonary anastomosis was needed, as the left one was no longer functioning. After placement of the second shunt, the hemoptysis disappeared. At age 14, flexible bronchoscopy revealed a foreign body granuloma at the left secondary carina. Rigid bronchoscopy and laser photoresection showed it to be the left vascular prosthesis, placed 10 years before. Surgery failed to remove it.
Asunto(s)
Cardiopatías Congénitas/cirugía , Hemoptisis/etiología , Hemorragia Posoperatoria/etiología , Arteria Pulmonar/cirugía , Arteria Subclavia/cirugía , Adolescente , Anastomosis Quirúrgica/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Broncoscopía , Diagnóstico Diferencial , Hemoptisis/diagnóstico , Hemoptisis/cirugía , Hemostasis Quirúrgica/métodos , Humanos , Terapia por Láser , Masculino , Hemorragia Posoperatoria/diagnóstico , Hemorragia Posoperatoria/cirugía , Radiografía Torácica , Recurrencia , ReoperaciónRESUMEN
BACKGROUND: The importance of cultural and adverse family-environment variables as risk factors for Disruptive Behaviour Disorder has been repeatedly shown, and hence a variation in rates and risk factors between cultures could be expected. Lower rates should be found in countries with strong and stable family ties, such as Spain. OBJECTIVE: Prevalence rate, severity and comorbidity of Disruptive Behaviour Disorder, as well as risk factors and help-seeking behaviour relating to this disorder, were studied in a general population random sample of 387 10 year-old children living in Valencia (Spain). METHODS: DSM-III-R diagnosis was established by means of the KIDDY-SADS (Kiddy Schedule for affective diseases and Schizophrenia (epidemiological version)) interview and severity of the disorder was evaluated with the General Assessment Functioning (GAF) Scale. Other variables measured were: sex, number of siblings, parental occupation, single-parent home, school failure, socioeconomic level, chronic somatic ailments and use of mental health services. RESULTS: Prevalence and severity parameters were low (for GAF70, prevalence = 11.1; for GAF60, prevalence = 4.9), albeit falling within the range reported in other countries. Morbidity profile and use of services did not substantially depart from the findings reported in other cultures. Different risk factors were associated with Attention Deficit Hyperactivity Disorder, Conduct Disorder and Oppositional Defiant Disorder, thus confirming the validity of considering them as separate dimensions. CONCLUSIONS: The findings did not support the hypothesis of lower rates and different risk factors and morbidity patterns in the Spanish sample studied.
Asunto(s)
Trastornos de la Conducta Infantil/epidemiología , Servicios de Salud Mental/estadística & datos numéricos , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Niño , Trastornos de la Conducta Infantil/economía , Comorbilidad , Trastorno de la Conducta/epidemiología , Demografía , Femenino , Humanos , Modelos Logísticos , Masculino , Prevalencia , Escalas de Valoración Psiquiátrica , Distribución Aleatoria , Factores de Riesgo , Muestreo , Distribución por Sexo , Padres Solteros , Factores Socioeconómicos , España/epidemiologíaRESUMEN
The morphology, organization and expression of proliferating cell nuclear antigen (PCNA) and the cytoskeletal proteins vimentin and GFAP in immature Bergmann glial cells were studied after a developmental injury induced by a single dose of the cytotoxic agent methylazoxymethanol (MAM) administered on postnatal day 5. This drug, which produces cell death of cerebellar granule cell precursors, did not induce apoptosis in Bergmann glial cells, which are in a proliferative stage. After MAM treatment, PCNA staining showed a severe depletion of PCNA-positive granule cell precursors, whereas PCNA-positive Bergmann glial nuclei in the Purkinje cell layer were preserved. Moreover, the quantitative analysis revealed an increase in the density of both Purkinje cells and PCNA-positive Bergmann glial cells per mm of Purkinje cell layer in MAM-treated rats relative to age-matched controls, but the numerical ratio between these two cell populations remains invariable after MAM treatment. Vimentin and GFAP immunocytochemistry revealed a reinforcement of the Bergmann glial palisade with overexpression of both proteins and thicker immunoreactive glial processes in MAM-treated rats. At the ultrastructural level, Bergmann glial processes closely associated with dying cells in different stages of apoptosis were observed. Frequently, these processes enclosed dying cells in extracellular compartments. Furthermore, phagosomes containing apoptotic bodies were found in Bergmann fibers of MAM-treated rats. These data indicate that the cell death of granule cell precursors triggers a reactive response in immature Bergmann glia. We suggest that this response reflects the plasticity of Bergmann glia to control the neuronal microenvironment in the maturing molecular layer, protecting healthy cells against the potentially harmful contents of dying cells. In situ labeling of cell death with the TUNEL method revealed that the cell death of granule cell precursors is of the apoptotic type. The participation of ameboid microglial cells in the phagocytosis of apoptotic cells was shown with tomato lectin histochemistry and ultrastructural analysis. Moreover, the presence of mitosis in this microglial population demonstrates its proliferative activity in regions of extensive cell death.
Asunto(s)
Apoptosis , Corteza Cerebelosa/patología , Gliosis/patología , Microglía/patología , Neuronas/patología , Animales , Corteza Cerebelosa/efectos de los fármacos , Corteza Cerebelosa/metabolismo , Técnica del Anticuerpo Fluorescente Directa , Proteína Ácida Fibrilar de la Glía/metabolismo , Gliosis/inducido químicamente , Gliosis/metabolismo , Etiquetado Corte-Fin in Situ , Lectinas/metabolismo , Masculino , Acetato de Metilazoximetanol/análogos & derivados , Acetato de Metilazoximetanol/toxicidad , Microglía/metabolismo , Mitosis , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Ratas , Ratas Sprague-Dawley , Células Madre , Vimentina/metabolismoRESUMEN
Administration of hypertonic NaCl solutions by intraperitoneal injection evokes a transient expression of immediate-early genes in the hypothalamic magnocellular neurons of supraoptic nuclei (SON), which is followed by an upregulation of arginine vasopressin synthesis and a general increase in cellular metabolic activity. Here we have analysed the changes that occur in the nucleus of SON neurons during the period of transient Fos expression after injection of hypertonic saline. Within the first 30 minutes after injection, the nuclei become significantly smaller, contain more condensed chromatin and incorporate less 3H-uridine than the controls. By 12 hours these effects are reverting and at 24 hours the nuclei are already more active than the controls. Additionally, we observe an initial decrease in the number of coiled bodies per nucleus within the first 2 hours, followed by a 3-fold increase at 24 hours after injection. As coiled bodies are transcription-dependent subnuclear 'organelles', these results further support the view that injection of hypertonic saline causes a transient inhibition of nuclear activity. Our data show that SON neurons respond to acute osmotic/stress stimuli first with inhibition and then with activation of gene expression. Importantly, inhibition of transcriptional activity occurs simultaneously with maximal accumulation of Fos protein in the nucleus, raising the possibility that activation of c-fos expression may cause repression of target genes.
Asunto(s)
Sistemas Neurosecretores/fisiología , Núcleo Supraóptico/fisiología , Transcripción Genética/fisiología , Equilibrio Hidroelectrolítico/fisiología , Animales , Núcleo Celular/ultraestructura , Expresión Génica/fisiología , Soluciones Hipertónicas , Masculino , Microinyecciones , Microscopía Inmunoelectrónica , Neuronas/fisiología , Neuronas/ultraestructura , Sistemas Neurosecretores/citología , Presión Osmótica , Ratas , Ratas Sprague-Dawley , Ribonucleoproteínas Nucleares Pequeñas/genética , Núcleo Supraóptico/citología , Tritio , Uridina/metabolismo , Uridina/farmacologíaRESUMEN
We present a cytological and biochemical study of the cell death of granule cell precursors in developing rat cerebellum following treatment with the cytotoxic agent methylazoxymethanol (MAM) during the first postnatal week. The density of apoptotic figures per square millimeter progressively increases after 6, 12, 24 and 44 h of treatment, whereas cells immunoreactive for proliferating cell nuclear antigen tend to disappear in the external granular layer (EGL). DNA migration on gel electrophoresis reveals a typical ladder pattern of internucleosomal cleavage following MAM treatment, whereas gel electrophoresis of rRNA shows a conspicuous degradation of both 28S and 18S rRNAs. Ultrastructural analysis has revealed the alterations of structures containing chromatin and ribonucleoprotein (RNP) in dying cells of the EGL. The typical granular beaded configuration of the condensed chromatin changes to a denser, more homogeneous texture suggesting nucleosomal disruption. The reorganization of RNP nuclear domains is reflected by the appearance of dispersed nucleoplasmic RNP particles and the formation of a coiled-body-like structure. However, typical nuclear domains involved in the splicing of RNAs, namely interchromatin granule clusters and typical "coiled bodies", are not found in apoptotic cells. Intranuclear bundles of filaments have also been detected. In the cytoplasm, the presence of dispersed single ribosomes is an initial sign of apoptosis. The massive dispersion and disruption of ribosomes detected after 24 h and 44 h of MAM treatment is reflected by the degradation of both 28S and 18s rRNAs. These results show that MAM treatment provides a useful experimental model for the study of apoptosis in the developing central nervous system. The organization of the cell nucleus in cells undergoing apoptosis clearly reflects a disruption of the nuclear compartments involved in transcription and the processing and transport of RNA and is related to the patterns of DNA and rRNA degradation.
Asunto(s)
Apoptosis , Carcinógenos/farmacología , Núcleo Celular/efectos de los fármacos , Cerebelo/efectos de los fármacos , ADN/efectos de los fármacos , Acetato de Metilazoximetanol/análogos & derivados , ARN Ribosómico/efectos de los fármacos , Animales , Núcleo Celular/ultraestructura , Cerebelo/crecimiento & desarrollo , Cerebelo/ultraestructura , ADN/metabolismo , Fragmentación del ADN , Femenino , Acetato de Metilazoximetanol/farmacología , Antígeno Nuclear de Célula en Proliferación/análisis , ARN Ribosómico/metabolismo , ARN Ribosómico 18S/efectos de los fármacos , ARN Ribosómico 18S/metabolismo , ARN Ribosómico 28S/efectos de los fármacos , ARN Ribosómico 28S/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Long-term control of high-grade brain tumors is rarely achieved with current therapeutic regimens. The aim of this study was to determine if low doses of tumor necrosis factor-alpha (TNF-alpha) could augment the effects of radiation in a glioma xenograft model and to evaluate hematological and other parameters that might indicate treatment-related toxicity. Nude mice were injected subcutaneously with C6 rat glioma cells and randomized into groups. Two different time-dose protocols were employed using intravenous human recombinant TNF-alpha and radiation beginning within 24 h after tumor cell implantation. The administration of radiation as a single agent slowed tumor progression, whereas TNF-alpha alone had no effect. However, TNF-alpha, especially when given twice per week before radiation for a total of four doses each, significantly increased the efficacy of the radiation. Low leukocyte counts were associated with combination treatment, whereas transforming growth factor-beta 1 levels were depressed in all treated groups. TNF-alpha did not modulate radiation-induced inhibition of C6 cell proliferation in vitro. The data show that TNF-alpha at relatively nontoxic doses can significantly enhance the antitumor effects of radiation against a rapidly growing glioma. This effect was more than additive, because TNF-alpha alone did not slow tumor progression.
Asunto(s)
Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Fármacos Sensibilizantes a Radiaciones/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Animales , Peso Corporal/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Replicación del ADN/efectos de los fármacos , ADN de Neoplasias/efectos de los fármacos , Glioma/tratamiento farmacológico , Glioma/patología , Humanos , Recuento de Leucocitos/efectos de los fármacos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Ratas , Proteínas Recombinantes , Bazo/citología , Bazo/efectos de los fármacos , Factor de Crecimiento Transformador beta/sangre , Trasplante Heterólogo , Factor de Necrosis Tumoral alfa/análisisRESUMEN
We have examined the reorganization of the cell nucleus in myelin-related Schwann cells (SCs) in a case of acute Guillain-Barré syndrome (GBS). Spinal root samples of the GBS case and human controls were processed for light and electron microscopy. The cytochemical EDTA method for ribonucleoproteins (RNPs) and a specific silver staining technique for nucleolar organizer regions were used on ultrathin sections. In SCs of the GBS case, we observed a significant increase in nuclear size (64.99 +/- 10.47 microns 2 in the GBS vs 35.07 +/- 8.74 microns 2 in the controls, mean +/- SD) accompanying partial decondensation of heterochromatin domains and elaboration of an extensive network of RNP-containing perichromatin fibrils. In addition, the formation of two types of nuclear structures, coiled bodies and nuclear bodies of Bouteille, was induced in SCs of the case of acute GBS. Free coiled bodies were observed in the nucleoplasm and were characteristically stained with both RNP and silver procedures. Typical "simple" and "complex" nuclear bodies were regularly found, sometimes in association with coiled bodies. On the basis of cell nucleus physiology, all of these changes are considered cytological indicators of enhanced transcription and cellular hyperactivity, and they seem to reflect a reactive response of SCs triggered by the constellation of cellular and humoral signals associated with acute GBS.
Asunto(s)
Núcleo Celular/patología , Polirradiculoneuropatía/patología , Células de Schwann/patología , Anciano , Humanos , Masculino , Proteínas de la Mielina/metabolismo , Regeneración Nerviosa/fisiologíaRESUMEN
BACKGROUND: In the adult rat, neuron-astroglia interactions in the supraoptic nucleus (SON) are characterized by the structural and functional plasticity of astrocytes in response to several physiological and experimental conditions. This study has analyzed the plasticity of the supraoptic nucleus astrocytes in response to the age-induced changes in neuronal activity. METHODS: The study was performed in 5-, 12-, 18- and 24-month-old rats. The cytology and organization of astrocytes in the SON were examined using glial fibrillary acidic and vimentin immunocytochemistry and ultrastructural and morphometric analysis. RESULTS: No significant age-related variations in the total number of neurons and astrocytes in the SON were detected, although a few degenerating neurons were found in old rats. An age-dependent increase in GFAP immunoreactivity was observed at the ventral glial lamina, perivascularly and between neuronal perikarya. Vimentin overexpression was also detected in ventral lamina astrocytes with advancing age. At the cell nucleus level, we observed an age-associated increase in nuclear size and in the number of coiled bodies, nuclear bodies, and "cleared" nucleoplasmic areas, as well as changes in the nucleolar organization. At the cytoplasmic level, characteristic ultrastructural features in astrocytes of old rats were the hypertrophy of intermediate filament bundles and the formation of an extensive network of Golgi stacks interlinked by tubulovesicular elements. Glial filaments were often associated with the nuclear envelope and polyribosomes. CONCLUSIONS: The increased GFAP and vimentin immunoreactivity and the morphometric and cytological changes in rat SON astrocytes may reflect a sustained upregulation of cellular activity with age, resulting in hypertrophy of glial perikarya and cell processes. Several factors that are known to influence the expression of the astrocytic phenotype, such as signals produced by degenerating neurons and activated microglia, as well as variations in neuronal activity are considered possible causes of the age-associated changes in SON astrocytes.