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1.
Clin. transl. oncol. (Print) ; 19(12): 1423-1429, dic. 2017. tab, ilus
Artículo en Inglés | IBECS | ID: ibc-168903

RESUMEN

The treatment of choice of metastatic PADC is systemic chemotherapy. In the last decade, there have been significant advances in this area. New combination poli-chemotherapy schemes have shown a significant increase in overall survival and progression-free survival without impairing quality of life. In addition, the value of second-line chemotherapy treatment has consolidated and a new concept called "therapeutic sequencing" has also emerged. The aim of this article is to review the different therapeutic options in metastatic PDAC based on patient's characteristics (AU)


No disponible


Asunto(s)
Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Metástasis de la Neoplasia/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
2.
Clin Transl Oncol ; 19(12): 1423-1429, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28623515

RESUMEN

The treatment of choice of metastatic PADC is systemic chemotherapy. In the last decade, there have been significant advances in this area. New combination poli-chemotherapy schemes have shown a significant increase in overall survival and progression-free survival without impairing quality of life. In addition, the value of second-line chemotherapy treatment has consolidated and a new concept called "therapeutic sequencing" has also emerged. The aim of this article is to review the different therapeutic options in metastatic PDAC based on patient's characteristics.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Calidad de Vida , Adenocarcinoma/secundario , Carcinoma Ductal Pancreático/secundario , Humanos , Neoplasias Pancreáticas/patología , Pronóstico , Neoplasias Pancreáticas
3.
Oral Oncol ; 70: 58-64, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28427761

RESUMEN

Head and neck cancer is one of the most frequent malignances worldwide. Despite the site-specific multimodality therapy, up to half of the patients will develop recurrence. Treatment selection based on a multidisciplinary tumor board represents the cornerstone of head and neck cancer, as it is essential for achieving the best results, not only in terms of outcome, but also in terms of organ-function preservation and quality of life. Evidence-based international and national clinical practice guidelines for head and neck cancer not always provide answers in terms of decision-making that specialists must deal with in their daily practice. This is the first Expert Consensus on the Multidisciplinary Approach for Head and Neck Squamous Cell Carcinoma (HNSCC) elaborated by the Spanish Society for Head and Neck Cancer and based on a Delphi methodology. It offers several specific recommendations based on the available evidence and the expertise of our specialists to facilitate decision-making of all health-care specialists involved.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas/patología , Consenso , Técnica Delphi , Neoplasias de Cabeza y Cuello/patología , Humanos , Estadificación de Neoplasias , España , Carcinoma de Células Escamosas de Cabeza y Cuello
4.
Cancer Chemother Pharmacol ; 75(2): 319-24, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25491381

RESUMEN

PURPOSE: Chemotherapy has improved the overall survival (OS) in patients (pts) with advanced gastric cancer (AGC). Docetaxel (D), oxaliplatin (O) and capecitabine (C) have shown interesting activity in this setting. We defined "suboptimal" pts as those with PS ECOG = 2, weight loss 10-25% and/or age ≥70 years. This population is usually underrepresented in AGC clinical trials. METHODS: We explored in 43 previously untreated "suboptimal" AGC pts the effect of "miniDOX" regimen (D: 40 mg/m(2) iv, day 1; O: 80 mg/m(2) iv, day 1; C: 625 mg/m(2) po bid, day 1 to day 21, every 21 days; after six courses, only C was maintained). Primary end point was response rate (RR), and secondary end points were adverse events (AE), progression-free survival (PFS) and overall survival (OS). RESULTS: Patients characteristics: PS ECOG = 2: 12 pts; weight loss 10-25%: 23 pts; median age 73.3 years (range 40-87; 28 pts were ≥70 years); 32 males; locally advanced: 8 pts/metastatic: 35 pts; primary site: gastric 32 pts/EGJ 11. Worst AE per pt (grade 3-4): neutropenia: 5 pts (febrile neutropenia: 3); pulmonary embolism (PE): 4 pts (3 of them suffered sudden death); diarrhea: 9 pts; paronychia: 2 pts; ictus: 1 pt; renal failure: 1 pt (this pt suffered infection/bacteriemia without neutropenia and died); hand-foot syndrome: 4 pts and asthenia: 5 pts. RESPONSE: CR: 1 pt, PR: 23 pts (RR: 56%), SD: 12 pts, progression: 3 pts, no determined: 4 pts. Median and 1 year actuarial PFS and OS were 5.5 months/18% and 13.3 months/52%, respectively. CONCLUSIONS: Although miniDOX's toxicity (mainly PE)has been important, its activity has been promising in "suboptimal" pts with AGC, and this combination should be further investigated in this setting.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Fluorouracilo/análogos & derivados , Compuestos Organoplatinos/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Taxoides/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Capecitabina , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Supervivencia sin Enfermedad , Docetaxel , Determinación de Punto Final , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Fluorouracilo/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Oxaliplatino , Selección de Paciente , Análisis de Supervivencia , Taxoides/administración & dosificación , Taxoides/efectos adversos , Resultado del Tratamiento , Pérdida de Peso/efectos de los fármacos
5.
Glia ; 55(14): 1437-48, 2007 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-17676593

RESUMEN

Astrocytes express voltage-gated calcium channels (VGCCs) that are upregulated in the context of the reactive astrogliosis occurring in several CNS pathologies. Moreover, the ability of selective calcium channel blockers to inhibit reactive astrogliosis has been revealed in a variety of experimental models. However, the functions and regulation of VGCC in astrocytes are still poorly understood. Interestingly, protein kinase C epsilon (PKCepsilon), one of the known regulators of VGCC in several cell types, induces in astrocytes a stellated morphology similar to that associated to gliosis. Thereby, here we explored the possible regulation of VGCC by adenovirally expressed PKCepsilon in astrocytes. We found that PKCepsilon potently increases the mRNA levels of two different calcium channel alpha(1) subunits, Ca(V)1.2 (L-type channel) and Ca(V)2.1 (P/Q-type channel). The mRNA upregulation was followed by a robust increase in the corresponding peptides. Moreover, the new calcium channels formed as a consequence of PKCepsilon activation are functional, since overexpression of constitutively-active PKCepsilon increased significantly the calcium current density in astrocytes. PKCepsilon raised currents carried by both L- and P/Q-type channels. However, the effect on the P/Q-type channel was more prominent since an increase of the relative contribution of this channel to the whole cell calcium current was observed. Finally, we found that PKCepsilon-induced stellation was significantly reduced by the specific L-type channel blocker nifedipine, indicating that calcium influx through VGCC mediates the change in astrocyte morphology induced by PKCepsilon. Therefore, here we describe a novel regulatory pathway involving VGCC that participates in PKCepsilon-dependent astrocyte activation.


Asunto(s)
Astrocitos/metabolismo , Encéfalo/metabolismo , Canales de Calcio/genética , Canales de Calcio/metabolismo , Proteína Quinasa C-epsilon/genética , Proteína Quinasa C-epsilon/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/efectos de los fármacos , Encéfalo/citología , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/efectos de los fármacos , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Canales de Calcio Tipo N/genética , Canales de Calcio Tipo N/metabolismo , Células Cultivadas , Vectores Genéticos , Gliosis/genética , Gliosis/metabolismo , Ratones , Ratones Endogámicos C57BL , Técnicas de Placa-Clamp , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transfección , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología
6.
Oncología (Barc.) ; 30(1): 12-20, ene. 2007. ilus, tab
Artículo en En | IBECS | ID: ibc-71509

RESUMEN

Objetivo: La actividad de la vinorelbina (VRL) en monoterapia en primera línea en pacientes concáncer de pulmón no microcítico (CPNM) ha sido contrastada en numerosos estudios. Las formulacionestanto oral en intravenosa tienen un perfil farmacocinético paralelo. Presentamos un estudio conVRL oral en pacientes (pts) ancianos con CPNM avanzado en primera línea.Material y métodos: Un global de 12 pts ≥ 70 años fueron reclutados desde Octubre 2005hasta Junio 2006. Los criterios de inclusión fueron: CPNM avanzado histológicamente confirmado,PS ≤ 2, enfermedad medible, buena reserva medular y función orgánica adecuada. La dosis del esquemaconsistió en 60 mg/m2 semanal durante 3 semanas seguidas (primer ciclo), seguido de 80 mg/m2semanal si no había toxicidad, hasta progresión o toxicidad inaceptable.Resultados: La mediana de edad fue de 74 años (rango: 71-79), todos los pts fueron varones, eigualmente todos con estadio IV. Los subtipos histológicos se distribuyeron en: adenocarcinoma en 5pts, carcinoma de células grandes en 1 pts y escamoso en 6 pts. Tres pts tenían PS 1 a la entrada en elestudio, y 9 pts PS 2, mientras que ninguno PS 0. La mediana de dosis de VRL administrada fue de 13ciclos (rango 3-23). Contando los 11 pts que recibieron el segundo ciclo, 7 de ellos pudieron escalar a80 mg/m2. Los otros 4 pts permanecieron en 60 mg/m2. No se observaron respuestas completas (RC),2 pts alcanzaron una respuesta parcial (RP), 6 pts con enfermedad estable (EE) y 4 pts con enfermedadprogresiva (EP). Respecto a la supervivencia, la mediana de seguimiento fue de 4 meses (rango 1-9meses). Hasta la fecha, no se ha alcanzado la mediana de supervivencia ni la mediana de tiempo a laprogresión. Tanto la supervivencia como la supervivencia libre de progresión (mediana de seguimiento4 meses) fue del 66% respectivamente. Respecto a la toxicidad, la tolerancia fue buena y no hubomuertes tóxicas. No se observaron toxicidades grado 4, y las toxicidades grado 3 fueron infrecuentes,con sólo 2 pacientes con neutropenia grado 3 y otros dos pacientes con astenia grado 3. Resto de lastoxicidades fueron grado 1 ó 2.Conclusiones: VRL oral puede ser una alternativa razonable a la administración intravenosa tantoen términos de actividad como de tolerabilidad en pacientes ancianos con CPNM avanzado


Purpouse: The activity of vinorelbine (VRL) as single agent in treatment-naïve inoperable nonsmall cell cancer (NSCLC) patients (pts) has been assessed in several published studies. Oral andintravenous formulation have a linearity of VRL pharmacokinetics with both routes of administration.This is a study with oral VRL in first line advanced NSCLC in elderly pts.Patients and methods: A total of 12 chemonaive elderly pts ≥ 70 years were recruited fromOctober 2005 through to June 2006. Principal inclusion criteria included histologically confirmed advancedNSCLC, performance status ≤ 2, measurable disease, appropriate bone marrow and organfunction. The dosage schedule was 60 mg/m2 once a week for three weeks (first cycle), followed if nottoxicity by 80 mg/m2 once a week, until disease progression or development of unacceptable toxicity.Results: The mean age was 74 years (range: 71 to 79), all males, and all pts stage IV. Histologysubtypes: adenocarcinoma in 5 pts, large cell carcinoma in 1 pts and squamous cell carcinoma in 6 pts.PS (ECOG) distribution was: 3 pts with PS 1, and 9 pts with PS 2. The median weekly VRL doseswas 13 (range 3-23). Out of 11 pts receiving the second cycle, 7 patients went a dose escalation to 80mg/m2. The other 4 pts remained at the 60 mg/m2 dose level. There were no complete responses (CR).Two (13%) of 12 patients achieved partial response (PR). There were 6 (50%) stable disease (SD) and4 (34%) progressive disease (PD). Respect survival, the median follow-up was 4 months (range 1-9months). Until date, the median survival time (MST) and median progression-free survival had notbeen reached; and survival and progression-free survival was 66% in both. Treatment with oral VRLin elderly patients was well tolerated, and there were no toxic deaths. No grade 4 toxicities wereobserved, and grade 3 toxicities were infrequent, exclusively neutropenia in 2 patients and asthenia inother 2 patients. Rest of toxicities were grade 1 or 2.Conclusions: Oral VRL appears to be a reasonable alternative intravenous VRL, both in terms of activity and tolerability in advanced, elderly NSCLC patients (AU)


Asunto(s)
Humanos , Masculino , Anciano , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Tasa de Supervivencia , Alcaloides/uso terapéutico , Administración Oral
7.
Clín. salud ; 13(2): 195-206, mayo 2002. tab
Artículo en Es | IBECS | ID: ibc-16980

RESUMEN

En España, la información sobre el diagnóstico de cáncer no está claramente estipulada. Los objetivos de este estudio son: 1) averiguar el nivel de información de los pacientes remitidos a nuestro servicio, 2) conocer las características del paciente relacionadas con su grado de información y 3) determinar la evolución con respecto a este tema. Entre Mayo-Noviembre de 1999, se incluyeron consecutivamente 116 pacientes que cumplimentaron un breve formulario en el momento de su llegada a nuestro servicio. Sólo un 48,3 per cent habían sido de su diagnóstico correctamente. Las características de los pacientes con mayor grado de información son: el sexo femenino (p= 0,00024), la edad menor de 58 años (p= 0,00006) y el padecer un cáncer mamario-ginecológico (p=0,00003).Los pacientes oncológicos tienen una información incompleta sobre su diagnóstico. Las características sociodemográficas y el tipo de cáncer afectan a la información. Las habilidades de comunicación y la empatía son instrumentos necesarios en la relación médico-paciente (AU)


Asunto(s)
Adulto , Anciano , Femenino , Masculino , Persona de Mediana Edad , Anciano de 80 o más Años , Humanos , Conocimientos, Actitudes y Práctica en Salud , Neoplasias/diagnóstico , Relaciones Médico-Paciente , Neoplasias/radioterapia
8.
Eur J Neurosci ; 13(6): 1147-54, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11285012

RESUMEN

Glutamate receptors have been linked to the regulation of several developmental events in the CNS. By using cortical slices of early postnatal mice, we show that in layer I cells, glutamate produces intracellular calcium ([Ca(2+)](i)) elevations mediated by ionotropic and metabotropic glutamate receptors (mGluRs). The contribution of mGluRs to these responses was demonstrated by application of tACPD, an agonist to groups I and II mGluRs, which evoked [Ca(2+)](i) increases that could be reversibly blocked by MCPG, an antagonist to groups I and II mGluRs. In the absence of extracellular Ca(2+), repetitive applications of tACPD or quisqualate, an agonist to group I mGluRs, elicited decreasing [Ca(2+)](i) responses that were restored by refilling a thapsigargin-sensitive Ca(2+) store. The use of specific group I mGluR agonists CHPG and DHPG indicated that the functional mGluR in layer I was of the mGluR1 subtype. Subtype specific antibodies confirmed the presence of mGlur1 alpha, but not mGluR5, in Cajal-Retzius (Reelin-immunoreactive) neurons.


Asunto(s)
Animales Recién Nacidos/metabolismo , Corteza Cerebral/metabolismo , Neuronas/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Animales , Calcio/metabolismo , Corteza Cerebral/citología , Membranas Intracelulares/metabolismo , Ratones , Ratones Endogámicos C57BL , Neuronas/efectos de los fármacos , Receptor del Glutamato Metabotropico 5 , Receptores de Glutamato Metabotrópico/agonistas , Proteína Reelina
9.
Eur J Neurosci ; 11(9): 3351-4, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10510201

RESUMEN

Transient pioneer neurons in the neocortical marginal zone generate an early corticofugal axonal projection at E12-E16 (Meyer et al. 1998). We have analysed the functional activity of glutamate and GABA receptors in such cells by measuring changes in intracellular calcium concentrations ([Ca2+]i). The activation of GABAA receptors with muscimol, as well as bath application of glutamate, lead to increases in [Ca2+]i in pioneer neurons. The stimulatory action of glutamate is mostly produced through the NMDA-type of ionotropic receptors. Metabotropic glutamate receptor activation has no effect on [Ca2+]i. Consistent with such results, immunocytochemical studies showed a prominent expression of GABAA and NMDA receptors in pioneer neurons. The activation of such receptors may be implicated in the remodelling of pioneer neurons during development.


Asunto(s)
Corteza Cerebral/metabolismo , Neuronas/metabolismo , Receptores de GABA-A/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Animales , Calbindinas , Calcio/química , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/crecimiento & desarrollo , Agonistas de Aminoácidos Excitadores/farmacología , Femenino , Colorantes Fluorescentes , Fura-2 , Agonistas de Receptores de GABA-A , Inmunohistoquímica , Neuronas/efectos de los fármacos , Embarazo , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato/agonistas , Proteína G de Unión al Calcio S100/metabolismo
10.
J Comp Neurol ; 397(4): 493-518, 1998 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-9699912

RESUMEN

Two major classes of early-born neurons are distinguished during early corticogenesis in the rat. The first class is formed by the cortical pioneer neurons, which are born in the ventricular neuroepithelium all over the cortical primordium. They appear at embryonic day (E) 11.5 in the lateral aspect of the telencephalic vesicle and cover its whole surface on E12. These cells, which show intense immunoreactivity for calbindin and calretinin, are characterized by their large size and axonal projection. They remain in the marginal zone after the formation of the cortical plate; they project first into the ventricular zone, and then into the subplate and the internal capsule. Therefore, these cells are the origin of the earliest efferent pathway of the developing cortex. Pioneer neurons are only present in prenatal brains. The second class is formed by subpial granule neurons, which form the subpial granular layer (SGL), previously considered to be found exclusively in the human cortex. SGL neurons are smaller than pioneer neurons. They are generated in a transient compartment of the retrobulbar ventricle between E12 and E14, and we propose the hypothesis that they invade the marginal zone, through tangential subpial migration, at different moments of fetal life. SGL neurons contain calbindin, calretinin, and gamma-aminobutyric acid (GABA), but the GABA-immunoreactive group becomes inconspicuous before birth. The extracellular matrix-like glycoprotein reelin, a molecule crucial for cortical lamination, is prenatally expressed by SGL neurons; postnatally, it is present in both Cajal-Retzius cells and subpial pyriform cells, both derivatives of SGL cells. In the rat, Cajal-Retzius cells are horizontal neurons that remain only until the end of the first postnatal week. They are located in layer I at a critical distance of approximately 20 microm from the pial surface and express reelin and, only occasionally, calretinin. Subpial pyriform cells coexpress reelin and calretinin and remain in layer I longer than Cajal-Retzius cells. Both pioneer neurons and subpial granule neurons are specific to the cortex. They mark the limit between the rudimentary cerebral cortex and olfactory bulb in the rat during early corticogenesis.


Asunto(s)
Animales Recién Nacidos/anatomía & histología , Corteza Cerebral/citología , Corteza Cerebral/embriología , Feto/citología , Neuronas/fisiología , Ratas/anatomía & histología , Ratas/embriología , Envejecimiento/fisiología , Animales , Línea Celular , Senescencia Celular/fisiología , Piamadre/citología , Piamadre/embriología , Ratas Wistar , Proteína Reelina
11.
Brain Res Dev Brain Res ; 101(1-2): 249-56, 1997 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-9263597

RESUMEN

Rats fed on low iodine diets (LIDs) result in a normal circulating level of triiodothyronine (T3), a low level of thyroxine (T4) and an elevated thyroid-stimulating hormone (TSH). These changes are similar to those observed in habitants who live in iodine-deficient areas and different from those observed when the hypothyroidism is produced by goitrogens. To study the effects of LID or goitrogens on the myelin basic protein (MBP) immunoreactivity (MBP-ir) during the myelination of the internal capsule, one group of experimental female rats was fed on an LID, and another group received a standard laboratory diet with methylmercaptoimidazole (MMI) added in the drinking water. Animals fed on a standard laboratory diet and animals fed on an LID supplemented with KI were used as controls. At P10, the MMI treatment has produced a more marked decrease in the surface density of MBP-ir processes with respect to controls than that produced in the LID animals. This decrease was correlated with the cerebral concentrations of triiodothyronine (T3) we found. During the postnatal development, a recovery in the levels of the surface density with respect to controls was observed in both experimental groups. The recovery occurred by P20 in the LID group and by P32 in the MMI rats.


Asunto(s)
Animales Recién Nacidos/fisiología , Antitiroideos/farmacología , Yodo/deficiencia , Metimazol/farmacología , Proteína Básica de Mielina/metabolismo , Animales , Química Encefálica/efectos de los fármacos , Recuento de Células , Femenino , Inmunohistoquímica , Fibras Nerviosas/fisiología , Embarazo , Radioinmunoensayo , Ratas , Ratas Wistar , Hormonas Tiroideas/metabolismo
12.
J Clin Invest ; 99(11): 2701-9, 1997 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9169500

RESUMEN

The most severe brain damage associated with thyroid dysfunction during development is observed in neurological cretins from areas with marked iodine deficiency. The damage is irreversible by birth and related to maternal hypothyroxinemia before mid gestation. However, direct evidence of this etiopathogenic mechanism is lacking. Rats were fed diets with a very low iodine content (LID), or LID supplemented with KI. Other rats were fed the breeding diet with a normal iodine content plus a goitrogen, methimazole (MMI). The concentrations of -thyroxine (T4) and 3,5,3'triiodo--thyronine (T3) were determined in the brain of 21-d-old fetuses. The proportion of radial glial cell fibers expressing nestin and glial fibrillary acidic protein was determined in the CA1 region of the hippocampus. T4 and T3 were decreased in the brain of the LID and MMI fetuses, as compared to their respective controls. The number of immature glial cell fibers, expressing nestin, was not affected, but the proportion of mature glial cell fibers, expressing glial fibrillary acidic protein, was significantly decreased by both LID and MMI treatment of the dams. These results show impaired maturation of cells involved in neuronal migration in the hippocampus, a region known to be affected in cretinism, at a stage of development equivalent to mid gestation in humans. The impairment is related to fetal cerebral thyroid hormone deficiency during a period of development when maternal thyroxinemia is believed to play an important role.


Asunto(s)
Hipotiroidismo Congénito/patología , Hipocampo/patología , Yodo/deficiencia , Neuroglía/patología , Efectos Tardíos de la Exposición Prenatal , Animales , Hipotiroidismo Congénito/congénito , Hipotiroidismo Congénito/metabolismo , Dieta , Desarrollo Embrionario y Fetal , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/embriología , Masculino , Intercambio Materno-Fetal , Neuroglía/efectos de los fármacos , Embarazo , Ratas , Ratas Wistar
13.
J Neurobiol ; 25(7): 808-18, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8089658

RESUMEN

In contrast to the permanent alterations resulting from neonatal hypothyroidism, the effects of juvenile-onset hypothyroidism on the number and distribution of spines along the apical shaft of pyramidal neurons of the visual cortex appeared to be potentially reversible with adequate thyroxine (T4) therapy (Ruiz-Marcos et al., 1980, Brain Res. 185:91-102 and 1982, Brain Res. 239:559-574). Treatment with 0.20 or 1.50 micrograms T4/100 g body weight per day had, however, only partially reversed the changes induced by juvenile-onset hypothyroidism. We here study whether or not a higher dose of T4 would totally reverse these effects. A group of rats were thyroid-ectomized at 40 days of age, and injected once daily with placebo or T4 (1.75 micrograms/100 g BW per day) from 70 to 90 days of age, a group on 1.50 micrograms being included to compare with previous results. Spine number and distribution were measured, as well as the concentrations of T4 and triiodothyronine (T3) in plasma, liver and brain. The activities of two hepatic enzymes were measured as thyroid hormone-sensitive biological end points. The 1.75-micrograms dose restored spine number to 88% of normal values and was markedly more effective than the 1.50-micrograms dose, which increased it to 68%. The degree of restoration appeared related to the concentration of T3. It is concluded that the changes caused by juvenile-onset hypothyroidism in the number and distribution of dendritic spines along the apical shafts of pyramidal neurons are reversible, although complete restoration might require a higher dose of T4, a continuous mode of administration, or longer period of treatment.


Asunto(s)
Corteza Cerebral/patología , Hipotiroidismo/patología , Células Piramidales/patología , Tiroxina/farmacología , Edad de Inicio , Animales , Corteza Cerebral/efectos de los fármacos , Dendritas/ultraestructura , Relación Dosis-Respuesta a Droga , Células Piramidales/efectos de los fármacos , Ratas , Ratas Wistar , Tiroidectomía , Tirotropina/sangre , Tiroxina/sangre , Factores de Tiempo , Triyodotironina/sangre
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