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1.
J Hazard Mater ; 263 Pt 2: 533-40, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24239258

RESUMEN

The specific adsorption of oxygenated and aliphatic gasoline components onto activated carbons (ACs) was studied under static and dynamic conditions. Ethanol and n-octane were selected as target molecules. A highly porous activated carbon (CA) was prepared by means of two processes: carbonization and chemical activation of olive stone residues. Different types of oxygenated groups, identified and quantified by TPD and XPS, were generated on the CA surface using an oxidation treatment with ammonium peroxydisulfate and then selectively removed by thermal treatments, as confirmed by TPD results. Chemical and porous transformations were carefully analyzed throughout these processes and related to their VOC removal performance. The analysis of the adsorption process under static conditions and the thermal desorption of VOCs enabled us to determine the total adsorption capacity and regeneration possibilities. Breakthrough curves obtained for the adsorption process carried out under dynamic conditions provided information about the mass transfer zone in each adsorption bed. While n-octane adsorption is mainly determined by the porosity of activated carbons, ethanol adsorption is related to their surface chemistry, and in particular is enhanced by the presence of carboxylic acid groups.


Asunto(s)
Contaminantes Atmosféricos/química , Carbono/química , Gasolina/análisis , Adsorción , Filtros de Aire , Ácidos Carboxílicos/química , Difusión , Restauración y Remediación Ambiental , Diseño de Equipo , Etanol/química , Gases , Calor , Hidróxidos/química , Octanos/química , Oxígeno/química , Porosidad , Compuestos de Potasio/química , Propiedades de Superficie , Compuestos Orgánicos Volátiles/química
2.
Histol Histopathol ; 22(12): 1355-64, 2007 12.
Artículo en Inglés | MEDLINE | ID: mdl-17701915

RESUMEN

The understanding of the cellular basis of osteoblastic cell-biomaterial interaction is crucial to the analysis of the mechanism of osseointegration. Cell adhesion is a complex process that is dependent on the cell types and on the surface microtopography and chemistry of the substrate. We have studied the role of microtopography in modulating cell adhesion, in vitro, using a human osteoblastic cell line for the assessment of actin cytoskeletal organization. Through application of CLSM combining reflection and fluorescence, 2D or 3D images of cytoskeleton were obtained. On smooth surfaces, Ti CP machined, predominantly planar bone cells with an axial ratio of 1.1 were randomly oriented, with stress fibers running in all directions, and thin filopodia. On TiCP Osseotite surfaces the osteoblastic cells conformed to the irregular terrain of the sustrate with focal adhesion sites only established on the relative topographical peaks separated for a longer distance than in the machined surface, and defined wide lamellopodia and long filopodia, with enhanced expression of stress fibers, forming large clear focal contacts with the rough surface. The cytoskeletal organization of cells cultured on rough titanium supports an active role for the biomaterial surface in the events that govern osteoblastic cell adhesion. The results enforce the role of the rough sustrate surface in affecting osteoblastic cell adhesion and provide valuable information for the design of material surfaces that are required for the development of an appropriate osteogenic surface for osteoblastic anchorage, compared to machined surface, in dental implants.


Asunto(s)
Actinas/metabolismo , Materiales Biocompatibles/química , Citoesqueleto/metabolismo , Implantes Dentales , Osteoblastos/metabolismo , Titanio/química , Adhesión Celular , Línea Celular , Humanos , Inmunohistoquímica , Ensayo de Materiales , Microscopía Confocal , Microscopía Electrónica de Rastreo , Oseointegración , Propiedades de Superficie
3.
J Agric Food Chem ; 55(15): 5960-5, 2007 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-17595106

RESUMEN

In this paper, the differentiation of green, black, Oolong, white, and Pu-erh teas has been carried out according to their free amino acid contents. Alanine, arginine, asparagine, aspartic acid, glutamic acid, isoleucine, histidine, leucine, phenylalanine, serine, theanine, threonine, and tyrosine have been determined by liquid chromatography with derivatization with o-phthalaldehyde and fluorescence detection. The chromatographic separation was achieved with a Hypersil ODS column and gradient elution. The amino acid contents were used as chemometric descriptors for classification purposes of different tea varieties. Principal component analysis, k-nearest neighbors, linear discriminant analysis, and artificial neural networks were applied to differentiate tea varieties. Using back-propagation multilayer perceptron artificial neural networks, 100% success in the classification was obtained. The most differentiating amino acids were glutamic acid, asparagine, serine, alanine, leucine, and isoleucine.


Asunto(s)
Aminoácidos/análisis , Té/química , Té/clasificación , Cromatografía Líquida de Alta Presión , Redes Neurales de la Computación
4.
Rheumatology (Oxford) ; 45(9): 1096-100, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16537577

RESUMEN

OBJECTIVE: To replicate the described association between MHC class I chain-related A (MICA) gene polymorphism and susceptibility to systemic lupus erythematosus (SLE). METHODS: MICA transmembrane microsatellite polymorphism was genotyped using a polymerase chain reaction (PCR)-based method. Genotyping of HLA-B* and DRB1* was performed using PCR and detection with a reverse sequence-specific oligonucleotide (SSO) probe system. Combined data for these three loci (HLA-B*, DRB1* and MICA) were obtained from a total of 333 patients and 361 healthy controls. RESULTS: Significant association with B*08 [P < 10(-7), odds ratio (OR) 3.17, 95% confidence interval (CI) 2.02-5.00], DRB1*0301 (P < 10(-7), OR 2.07, 95% CI 1.59-2.68) and MICA5.1 (P = 0.01, OR 1.23, 95% CI 1.04-1.46) was observed. The combinations DRB1*0301-MICA5.1-B8 and HLA-DRB1*0301-B*08-positive and MICA5-1-negative were more frequent among SLE patients (11.4 vs 3.3% in healthy controls, P = 3.9 x 10(-5), OR 3.76, 95% CI 1.85-7.73, and 6.9 vs 1.7%, P = 0.0007, OR 4.32, 95% CI 1.68-13.10, respectively). Additionally, individuals who were HLA-DRB1*0301-B*08-negative and MICA5-1-positive were less frequent among patients (22.2 vs 31.3% in healthy controls, P = 0.007, OR 0.63, 95% CI 0.44-0.89) and the magnitude of the OR was similar to that obtained in individuals negative for all the three factors (OR 0.69, 95% CI 050-0.94). Further analysis performed to detect independent association strongly suggested that the association between MICA5.1 and SLE is secondary to the linkage disequilibrium of this allele with B*08. CONCLUSIONS: Our results do not support an independent association of MICA gene polymorphism with susceptibility to SLE.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo Genético , Adolescente , Adulto , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Antígenos HLA-B/genética , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Masculino , Persona de Mediana Edad
5.
Cell Biol Int ; 28(5): 397-402, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15193283

RESUMEN

One of the mechanisms that has been put forward for the development of the androgen-resistant status is neuroendocrine differentiation. Neuroendocrine cells secrete neuropeptides that may represent one of the possible molecular bases by which hormone-dependent prostate cancer cells could escape treatment. LNCaP prostate cancer cells were treated with either etoposide or neuropeptides. Morphological changes related to apoptosis and cell viability were assessed. Changes in intracellular ion content were quantitatively analyzed by electron probe X-ray microanalysis. Etoposide treatment consistently induces a decrease in K and an increase in Na, which are inhibited by bombesin or calcitonin. The Na/K ratio increased markedly after exposure to etoposide, and both bombesin and calcitonin blocked this increase. Etoposide also caused changes in the intracellular P and S concentrations that to a large extent could be blocked by neuropeptides. These results support the hypothesis that neuropeptides confer anti-apoptotic capabilities onto non-neuroendocrine cells in close proximity to neuroendocrine cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Etopósido/antagonistas & inhibidores , Neuropéptidos/farmacología , Potasio/metabolismo , Neoplasias de la Próstata/metabolismo , Sustancias Protectoras/farmacología , Sodio/metabolismo , División Celular/efectos de los fármacos , Línea Celular Tumoral , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Microanálisis por Sonda Electrónica/métodos , Etopósido/farmacología , Humanos , Cinética , Masculino , Microscopía Electrónica de Rastreo/métodos , Neoplasias de la Próstata/tratamiento farmacológico
6.
Histol Histopathol ; 19(3): 951-61, 2004 07.
Artículo en Inglés | MEDLINE | ID: mdl-15168357

RESUMEN

It has been suggested that neuroendocrine (NE) cells provide paracrine stimuli for the propagation of local carcinoma cells and that NE differentiation is associated with the progression of prostate cancer toward an androgen-independent state. Apoptosis comprises a critical intracellular defense mechanism against tumorigenic growth and is associated with a number of changes in the elemental content of the cell. The neuropeptides bombesin and calcitonin, which inhibit etoposide-induced apoptosis, also inhibit the etoposide-induced elemental changes in prostate carcinoma cells. This important fact strengthens the link between apoptosis and changes in the intracellular elemental content. This protective effect on etoposide-induced apoptosis appears to be quite similar in androgen-dependent and androgen-independent cell lines. This confirms that neuropeptides confer antiapoptotic capabilities on non-neuroendocrine cells in close proximity to neuroendocrine cells. It can therefore be speculated that certain neuroendocrine peptides can increase the survival and further growth of neighboring cells and may thereby contribute to the aggressive clinical course of prostate tumors containing neuroendocrine elements. In addition, this correlation provides an objective basis for the study of neuropeptide target points and may be helpful for alternative therapeutic protocols using neuropeptide inhibitors in the treatment of patients with advanced prostatic carcinoma. The culture techniques described were, thus, designed in order to achieve two important goals. First, the development of an in vitro model that allows an approach to neuroendocrine differentiation in prostate cancer and its role in apoptosis blockage. Second, the method has been designed in order to permit rapid cryofixation of intact cell monolayers for subsequent x-ray microanalysis.


Asunto(s)
Apoptosis/efectos de los fármacos , Iones/metabolismo , Neuropéptidos/farmacología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Línea Celular Tumoral , Microanálisis por Sonda Electrónica , Humanos , Masculino , Microscopía Electrónica de Rastreo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/ultraestructura
7.
Rev. chil. pediatr ; 73(1): 51-55, ene.-feb. 2002. tab
Artículo en Español | LILACS | ID: lil-314820

RESUMEN

Introducción: En los últimos años se han desarrollado sistemas de apoyo ventilatorio en domicilio (SAVED), que han logrado tratar pacientes con insuficiencia respiratoria crónica en su hogar. Objetivo: revisar nuestra experiencia en los pacientes con SAVED. Pacientes y Método: se revisaron las fichas de los 15 pacientes ( 9 mujeres) con SAVED dados de alta del Servicio de Pediatría del Hospital Clínico de la Pontificia Universidad Católica de Chile, entre enero de 1993 y diciembre 2000. Se describen las características del grupo y su seguimiento. Resultados: sus edades al alta fluctuaron entre 5 meses y 15 años; 6 tenían enfermedad neuromuscular, 4 daño pulmonar crónico, 1 deformidad torácica y 4 traqueobroncomalacia grave. Doce requirieron traqueostomía, de estos, 4 utilizaron ventilación mecánica (PLV-102, LifeCare) y 8 CPAP con generador de flujo (Downs) y válvula de PEEP, y 3 ventilación nasal a través de BIPAP. El alta fue entre 2 y 4 meses desde el ingreso y la implementación del SAVED entre 1 y 4 meses, de acuerdo a la realidad familiar y previsional. El período de seguimiento fue de 3 meses a 8 años. La tasa de reingreso fue 2,5 y 0,4 ingresos/paciente/año por morbilidad y por falla de sistema respectivamente, el tiempo promedio de estadía en el hospital fue de 16,5 ñ 9 días/año. Se logró la retirada del SAVED en 5 pacientes y 1 niño falleció debido a su enfermedad neurológica. En resumen, nuestra experiencia demuestra que los SAVED son una alternativa real en el manejo de pacientes con insuficiencia respiratoria crónica grave. Esta terapia presenta escasas complicaciones, permite enviar al paciente a su casa y disminuye en forma significativa los costos del tratamiento


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Servicios de Atención a Domicilio Provisto por Hospital , Respiración Artificial/métodos , Insuficiencia Respiratoria , Edad de Inicio , Tiempo de Internación , Insuficiencia Respiratoria , Traqueostomía , Ventilación con Presión Positiva Intermitente/métodos
8.
An. med. interna (Madr., 1983) ; 18(11): 569-572, nov. 2001.
Artículo en Es | IBECS | ID: ibc-8204

RESUMEN

Objetivo: Nos propusimos describir las características demográficas y los hábitos de consumo de alcohol de un grupo de pacientes ambulatorios. Intentamos discernir la influencia de la edad, sexo, habitat y nivel socioeconómico sobre el hábito enólico. Diseño experimental: Nuestro estudio es retrospectivo, de base institucional. Pacientes: 164 pacientes ambulatorios, en seguimiento en nuestras consultas externas de la unidad de Hepatología por enfemedad hepática alcohólica. Resultados: La edad media de inicio fue 18,6 (7,36) años; los años de enolismo medio fueron de 35,4 (13,5) años y el consumo medio de alcohol de 161,2 (116,7) gramos de alcohol/día. Solo en 16 hombres (8 por ciento) se observó un consumo menor de 60 gramos de alcohol al día, y 5 mujeres (35,7 por ciento) consumían menos de 40 gramos de alcohol al día. El consumo de alcohol a lo largo de la vida estuvo correlacionado con el índice de Maddrey al final del estudio (r=+0,407). De igual forma el consumo diario de gramos de alcohol estuvo correlacionado con el aspecto ecográfico del hígado(r=+0,283), apreciándose también correlación de dicha técnica de imagen (r=+0,301) con el Tiempo de Protrombina al inicio del estudio. El porcentaje de pacientes que presentaron al menos un episodio de descompensación de su cirrosis fue del 39 por ciento. Conclusiones: La edad de inicio ronda la mayoría de edad . El consumo de alcohol a lo largo de la vida, estuvo correlacionado con el tiempo de protrombina en la última visita y el aspecto ecográfico del hígado (AU)


Asunto(s)
Persona de Mediana Edad , Masculino , Femenino , Humanos , Atención Ambulatoria , España , Alcoholismo
10.
Cell Biol Int ; 25(6): 499-508, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11407855

RESUMEN

Apoptosis comprises a critical intracellular defense mechanism against tumourigenic growth. We have been interested in the relationship between morphological changes and intracellular concentration of several cations after etoposide-induced apoptosis in androgen-independent prostate cancer cells. SEM and X-ray microanalysis were performed on freeze-dried PC3 cells after etoposide treatment, and correlated with the morphological features observed after examination by light and fluorescence microscopy. Cell viability assays were also performed. A significant decrease in intracellular Cl(-) and K(+)and a progressive increase in Mg(2+) and Na(+) were observed, with parallel changes in cellular volume as cells passed through three morphological stages of apoptosis. The use of EPXRMA made it possible to evaluate alterations in element composition in prostate cancer cell apoptosis and may be a helpful tool for further studies on apoptosis in prostate cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/fisiología , Microanálisis por Sonda Electrónica , Etopósido/farmacología , Neoplasias de la Próstata , Apoptosis/efectos de los fármacos , División Celular/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , ADN de Neoplasias/análisis , Citometría de Flujo , Humanos , Masculino , Microscopía Electrónica de Rastreo , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/ultraestructura
11.
An Med Interna ; 18(11): 569-72, 2001 Nov.
Artículo en Español | MEDLINE | ID: mdl-11862766

RESUMEN

AIMS: We tried to show the demographic characteristic and alcohol intake habits among our outpatients. We study the influence of age, sex, habitat and socioeconomical status on alcoholic habit. DESIGN: Retrospective and institution based study. Patients. 164 patients who were followed up for alcohol liver disease in our outpatient section. RESULTS: Average age to start drinking alcohol was 18.6 (7.36) years, years of alcoholism were 35.4 (13.5) years, average daily alcohol intake was 161.2 (116.7) grams of pure alcohol. Only 16 men (8%) drank less than 60 grams a day. 5 (35.7%) women drank less than 40 grams a day. Life-cumulative alcohol intake was correlated with Maddrey's score at the end of the study (r = +0.407). Average daily alcohol intake was correlated with ultrasonographic features of the liver (r = +0.283), we appreciated that Prothrombin Time was also correlated with ultrasonographic features of the liver (r = +0.301). The percentage of patients who suffer, at least one decompensation of their disease was 39%. CONCLUSIONS: Average age to start drinking is about legal age. Life-cumulative alcohol intake was related to Prothrombin Time and ultrasonographic features of the liver.


Asunto(s)
Alcoholismo/epidemiología , Atención Ambulatoria , Alcoholismo/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , España
12.
An. med. interna (Madr., 1983) ; 17(11): 572-575, nov. 2000. tab, graf
Artículo en Es | IBECS | ID: ibc-229

RESUMEN

Objetivo: Valorar la utilidad de la transferrina deficiente en carbohidratos (CT) en el diagnóstico del alcoholismo crónico, la ingesta reciente y la abstinencia, comparándola con los marcadores biológicos más reconocidos, especialmente el VCM y la GT. Método: Estudio prospectivo en 87 sujetos: 22 controles, 42 pacientes alcohólicos crónicos en abstinencia y 23 alcohólicos activos, sometiendo un subgrupo de estos últimos a un periodo de abstinencia de 15 días. Valorando y comparando la CDT con otros parámetros biológicos reconocidos, en los diferentes grupos. Resultados: Para el alcoholismo crónico encontramos diferencia significativa en el VCM y la GGT. En el caso de la ingesta alcohólica reciente existió diferencia significativa en el VCM, la GGT y sobretodo en la CDT. En la abstinencia reciente el único que presentó diferencia significativa fue la CDT. Conclusiones: Según nuestros resultados la CDT tiene escasa utilidad erl el diagnóstico del alcoholismo crónico, siendo superada en esta propiedad por los marcadores clásicos (VCM y GGT). La CDT, sin embargo, es un marcador válido y efectivo para el diagnóstico de la ingesta alcohólica reciente, superando a la GGT y al VCM. Y es el único válido para el diagnóstico de la abstinencia reciente. Estimamos por tanto que, sería aconsejable el uso clínico de la CDT con criterios restringidos, para el diagnóstico de la ingesta alcohólica reciente y sobre todo para el diagnóstico de la abstinencia (AU)


Asunto(s)
Adulto , Anciano , Persona de Mediana Edad , Humanos , Alcoholismo/diagnóstico , Alcoholismo/sangre , Transferrina/análisis , Transferrina/análogos & derivados , Biomarcadores/sangre , Templanza , Transferrina , Biomarcadores , Estudios Prospectivos , Alcoholismo
13.
Histol Histopathol ; 15(3): 729-38, 2000 07.
Artículo en Inglés | MEDLINE | ID: mdl-10963117

RESUMEN

BACKGROUND: Neuroendocrine differentiation in prostatic carcinoma has been related to regulation of proliferation and metastatic potential and correlated with prognosis. More than 80% of prostate carcinomas initially respond to androgen ablation, but most relapse, due to the heterogeneous presence of androgen-dependent and independent clones. The pathways of cellular proliferation and apoptosis are inexorably linked to minimize the occurrence of neoplasia, and disfunction of apoptosis is proposed as a pathogenic process in malignant tumors. Androgen-dependent prostatic cancer cells undergo apoptosis after androgen deprivation, but not androgen-independent ones due to a defect in the initiation step. Anyway, they retain the basic cellular machinery to undergo apoptosis. We suggest a possible role of neuroendocrine differentiation in the onset and regulation of apoptosis in prostatic neoplasia. METHODS: LNCaP, PC-3 and DU 145 prostatic cancer cell lines were induced to undergo apoptosis after treatment with etoposide alone or plus androgen ablation. We tested the role of neuropeptides bombesin and calcitonin at modulating etoposide induced apoptosis. RESULTS: Etoposide-induced apoptosis in all cancer cell lines was achieved. In LNCaP androgen ablation was also required. Apoptosis is prevented in all three lines when bombesin was added. Calcitonin addition prevents apoptosis in PC-3, LNCaP and in an etoposide dose-dependent way in DU 145. CONCLUSION: Neuropeptides bombesin and calcitonin can modulate the apoptotic response of prostate cancer cells by inducing resistance to etoposide-induced apoptosis, suggesting that neuropeptides can be used as a target of therapeutical approach in prostatic carcinoma.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Bombesina/farmacología , Calcitonina/farmacología , Etopósido/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Resistencia a Antineoplásicos , Humanos , Masculino , Células Tumorales Cultivadas
14.
J Auton Nerv Syst ; 78(2-3): 136-40, 2000 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-10789693

RESUMEN

The nicotinic axon reflex-mediated sudomotor response was studied in mice and rats by recording the impressions of sweat droplets made in silicone molds after local injection of nicotine, and compared with sweating induced by acetylcholine and pilocarpine. Nicotine failed to activate mouse plantar sweat glands at any of the concentrations used (from 3 x 10(-6) to 3 x 10(-1) M). On the contrary, both acetylcholine and pilocarpine produced a dose-dependent increase in the number of secreting sweat glands. The location of sweat glands reactive to pilocarpine and acetylcholine was similar and restricted to the pads near the site of injection. We conclude that the sudomotor axon reflex response mediated by nicotinic receptors is not present in the mouse and the rat.


Asunto(s)
Axones/efectos de los fármacos , Axones/fisiología , Receptores Nicotínicos/efectos de los fármacos , Receptores Nicotínicos/metabolismo , Glándulas Sudoríparas/efectos de los fármacos , Glándulas Sudoríparas/inervación , Sudoración/efectos de los fármacos , Sudoración/fisiología , Fibras Simpáticas Posganglionares/efectos de los fármacos , Fibras Simpáticas Posganglionares/fisiología , Acetilcolina/farmacología , Animales , Axones/ultraestructura , Femenino , Pie/anatomía & histología , Pie/inervación , Pie/fisiología , Humanos , Ratones , Agonistas Muscarínicos/farmacología , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Pilocarpina/farmacología , Ratas , Ratas Sprague-Dawley , Receptores Muscarínicos/efectos de los fármacos , Receptores Muscarínicos/metabolismo , Glándulas Sudoríparas/fisiología , Fibras Simpáticas Posganglionares/citología , Factores de Tiempo , Vasodilatadores/farmacología
15.
J Peripher Nerv Syst ; 5(4): 191-208, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11151980

RESUMEN

Aging deeply influences several morphologic and functional features of the peripheral nervous system (PNS). Morphologic studies have reported a loss of myelinated and unmyelinated nerve fibers in elderly subjects, and several abnormalities involving myelinated fibers, such as demyelination, remyelination and myelin balloon figures. The deterioration of myelin sheaths during aging may be due to a decrease in the expression of the major myelin proteins (P0, PMP22, MBP). Axonal atrophy, frequently seen in aged nerves, may be explained by a reduction in the expression and axonal transport of cytoskeletal proteins in the peripheral nerve. Aging also affects functional and electrophysiologic properties of the PNS, including a decline in nerve conduction velocity, muscle strength, sensory discrimination, autonomic responses, and endoneurial blood flow. The age-related decline in nerve regeneration after injury may be attributed to changes in neuronal, axonal, Schwann cell and macrophage responses. After injury, Wallerian degeneration is delayed in aged animals, with myelin remnants accumulated in the macrophages being larger than in young animals. The interaction between Schwann cells and regenerative axons takes longer, and the amount of trophic and tropic factors secreted by reactive Schwann cells and target organs are lower in older subjects than they are in younger subjects. The rate of axonal regeneration becomes slower and the density of regenerating axons decrease in aged animals. Aging also determines a reduction in terminal and collateral sprouting of regenerated fibers, further limiting the capabilities for target reinnervation and functional restitution. These age-related changes are not linearly progressive with age; the capabilities for axonal regeneration and reinnervation are maintained throughout life, but tend to be delayed and less effective with aging.


Asunto(s)
Envejecimiento/fisiología , Regeneración Nerviosa/fisiología , Sistema Nervioso Periférico/fisiología , Animales , Humanos , Fibras Nerviosas/fisiología
16.
An Med Interna ; 17(11): 572-5, 2000 Nov.
Artículo en Español | MEDLINE | ID: mdl-11322028

RESUMEN

OBJECTIVE: To evaluate the utility of carbohydrate deficient transferrin (CDT) for the chronic alcoholism diagnostic, the recent intake and the abstinence, comparing it with the most recognized biological markers, specially the MCV and the GGT. METHODS: We study 87 subjects: 22 controls, 42 subjects abstinent chronic alcoholics and 23 patient active alcoholics. From the last group we subject the middle to a 15 days abstinence period. We compare the CDT with the mos recognized markers in the difference groups. RESULTS: We found significant difference with MCV and GGT in the chronic alcoholism diagnostic. There were significant difference with MCV, GGT and specially CDT in the case of recent alcoholic intake. CDT was the only one that shows significant difference in recent abstinence. CONCLUSION: According to our results the CDT is a poor marker of chronic alcoholism. The classical markers (MCV nd GGT) are better on tha propriety. CDT, however, is a valid and effective marker for the recent alcohol intake, it is better than GGT and MCV. And it is the only valid marker for the recent abstinence. So, we estimate that, it would be advisable the CDT clinical use with restringed criterions for the recent alcoholic intake diagnostics and, specially for the abstinence one.


Asunto(s)
Alcoholismo/sangre , Alcoholismo/diagnóstico , Templanza , Transferrina/análisis , Biomarcadores/sangre , Humanos , Estudios Prospectivos , Transferrina/análogos & derivados
17.
Muscle Nerve ; 22(3): 329-40, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10086893

RESUMEN

We investigated the neuropathic effects of cisplatin in two groups of mice treated with 5 or 10 mg/kg/week of cisplatin for 7 or 8 weeks. Peripheral nerve functions were evaluated by sweat imprints, and electrophysiological, rotarod, and nociceptive tests. Protein gene product 9.5 (PGP), calcitonin gene-related peptide (CGRP), and vasoactive intestinal peptide (VIP) were immunohistochemically localized in footpads. Tibial nerves were analyzed morphometrically. Functional deficits developed progressively with higher cumulative doses, more markedly in mice treated with high than in those with low doses. From cumulative doses of 10 mg/kg, significant declines in sensory nerve conduction velocity and sudomotor responses were found, whereas motor and nociceptive functions were involved later. There were no morphometrical changes in tibial nerves. A marked decrease of CGRP- and VIP-immunoreactive nerves occurred in samples from treated mice, whereas PGP-labeled profiles decreased mildly at late stages. Impairment of the content of neuropeptides with neurosecretor role was detectable earlier than functional abnormalities. Immunohistochemical analysis of skin biopsies offers a useful diagnostic tool for peripheral neuropathies.


Asunto(s)
Antineoplásicos , Cisplatino , Enfermedades del Sistema Nervioso/inducido químicamente , Enfermedades del Sistema Nervioso/fisiopatología , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Relación Dosis-Respuesta a Droga , Electrofisiología , Femenino , Inmunohistoquímica , Ratones , Actividad Motora/fisiología , Enfermedades del Sistema Nervioso/metabolismo , Nociceptores/fisiología , Sudoración/fisiología , Tioléster Hidrolasas/metabolismo , Ubiquitina Tiolesterasa , Péptido Intestinal Vasoactivo/metabolismo
18.
Histol Histopathol ; 14(1): 125-34, 1999 01.
Artículo en Inglés | MEDLINE | ID: mdl-9987657

RESUMEN

Metastatic prostatic cancer is typically refractory to androgen ablation therapy due to the presence of androgen-independent clones in the neoplasia. A therapeutical approach which could effectively control androgen-dependent and independent cells is, thus, needed. Maybe the failure of certain cancer cells to engage in apoptosis could explain the inherent drug resistance of many tumors. Anyway, these cells can retain the ability to undergo apoptosis in response to an adequate stimulus. We tested whether etoposide, a topoisomerase II inhibitor, could induce apoptosis in androgen-dependent (LNCaP) as well as independent (PC-3 and DU 145) human prostate cancer cell lines. Morphological examination was performed, as it is regarded as one of the most reliable parameters for the detection of apoptotic changes. Complementarily, biochemical and flow cytometric studies were also used. Characteristical changes of apoptosis were demonstrated in PC-3, Du 145, and LNCaP cancer cells after treatment with etoposide. These cells, thus, retain the ability to undergo apoptosis under adequate conditions, in a promising approach to hormone refractory prostate cancer therapy.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis , Etopósido/farmacología , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Andrógenos/metabolismo , División Celular , Supervivencia Celular , Humanos , Cinética , Masculino , Células Tumorales Cultivadas
19.
J Auton Nerv Syst ; 74(2-3): 134-42, 1998 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9915629

RESUMEN

Functional sudomotor responses have been studied in sweat glands reinnervated after sciatic nerve crush and partially denervated by cisplatin intoxication in the mouse. The sudomotor function mediated by the sciatic nerve was evaluated by silicone imprints on the plantar surface of the hindpaws. Five days after nerve crush, completely denervated sweat glands became unresponsive to cholinergic stimulation with pilocarpine. During the following weeks, the number of reinnervated, reactive sweat glands increased progressively to reach a maximum of 89% of preoperative control counts by 40 days after nerve crush. At this time, the mean volume of sweat secreted per gland was normal, but reinnervated glands showed a secretory activity abnormally sustained over time after pilocarpine stimulation and, on the other hand, had an increased resistance to the inhibition of secretion induced by atropine. The effects of cisplatin administration on sudomotor function were investigated in two groups of mice, one treated with high doses of cisplatin (10 mg/kg/week for 4 weeks) and another treated with low doses of cisplatin (5 mg/kg/week for 8 weeks). Cisplatin intoxication produced abnormal sudomotor responses indicative of denervation from cumulative doses of 10 mg/kg. The first abnormality found was a partial resistance of sweat glands to atropine, followed by a decrease in the sweat output per gland and finally a decline in the number of sweat glands activated by pilocarpine. These abnormalities in the sudomotor responses were more pronounced in mice treated with a high dose than in those with a lower dose regime.


Asunto(s)
Fibras Colinérgicas/fisiología , Regeneración Nerviosa/fisiología , Glándulas Sudoríparas/inervación , Animales , Antineoplásicos/farmacología , Atropina/farmacología , Sistema Nervioso Autónomo/efectos de los fármacos , Sistema Nervioso Autónomo/fisiología , Fibras Colinérgicas/efectos de los fármacos , Cisplatino/farmacología , Femenino , Ratones , Compresión Nerviosa , Parasimpatolíticos/farmacología , Parasimpaticomiméticos/farmacología , Pilocarpina/farmacología , Nervio Ciático/citología
20.
Rev. chil. pediatr ; 68(4): 171-4, jul.-ago. 1997.
Artículo en Español | LILACS | ID: lil-207186

RESUMEN

Evaluar las ventajas del sistema de diálisis peritoneal agudo automatizada en comparación con el procedimiento manual en niños con síndrome hemolítico urémico. Entre 30 pacientes (edad ñ 20,4 meses) atendidos por síndrome hemolítico urémico en un período de 75 meses (enero 1990 a marzo de 1997) en un hospital universitario de Santiago, Chile. 15 requirieron diálisis peritoneal y en 11 se empleó el método automatizado y en los otros 4 el manual. Los pacientes sometidos a procedimiento manual registraron 71,3 atenciones diarias de enfermería en promedia solo para el manejo de la diálisis en comparación con 5,6 atenciones para los tratados con el procedimiento automatico de ciclado, en el que no se registraron complicaciones. La mitad de los pacientes con síndrome hemolítico urémico requirió diálisis peritoneal aguda


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Diálisis Peritoneal/economía , Síndrome Hemolítico-Urémico/terapia , Estudios de Seguimiento
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