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1.
Skeletal Radiol ; 50(8): 1717-1721, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33517510

RESUMEN

COVID-19 has presented with a variety of manifestations including peripheral neurological symptoms. The most commonly associated peripheral neuropathies described with COVID-19 are Guillain-Barre syndrome and its variants as well as critical illness polyneuropathy. We report in this paper the distinct MRI findings of an unusual case of peripheral neuropathy associated with COVID-19. These findings are similar to those seen in Guillain-Barre syndrome or one of its variants, although differing from the classic condition in certain key clinical and radiological features.


Asunto(s)
COVID-19 , Enfermedades del Sistema Nervioso Periférico , Humanos , Desnervación Muscular , Atrofia Muscular/diagnóstico por imagen , Enfermedades del Sistema Nervioso Periférico/diagnóstico por imagen , SARS-CoV-2
2.
Brain Topogr ; 32(2): 283-285, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30426267

RESUMEN

Acute pain from mucositis in patients with head and neck cancer (HNC) undergoing radiation therapy (RT) is common, and may not respond well to narcotics. We used low resolution electromagnetic tomography z-score neurofeedback (LFBz) to investigate whether patients could modify brain wave activity associated with acute pain and whether this would reduce the experience of pain. HNC patients scheduled for RT had baseline pre-pain onset measures (EEG and numeric rating scale) collected before RT and then at pain onset before using analgesics, after each LFBz session and at the end of RT. Up to six sessions of LFBz training were offered over the remaining RT. Up to six 20-min sessions of LFBz were offered over the remaining RT. Data were collected before and after each LFBz session and at the end of RT. Seventeen patients recruited; fourteen were treated and reported decreased pain perception. LFBz allowed patients to modify their brain activity in predesignated areas of the pain matrix toward the direction of their baseline, pre-pain condition (including Brodmann areas (BAs) 3, 4, 5, 13, 24, and 33). LFBz can modify brain regions relevant for pain and these changes were associated with self-reported decreases in pain perception.


Asunto(s)
Dolor Agudo/etiología , Neoplasias de Cabeza y Cuello/complicaciones , Imagen por Resonancia Magnética/métodos , Neurorretroalimentación , Manejo del Dolor/métodos , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Resultado del Tratamiento
3.
Orthopade ; 48(10): 844-848, 2019 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-31041462

RESUMEN

BACKGROUND AND OBJECTIVE: Thoracic spinal stenosis is characterized by a reduction in the volume of the thoracic spinal canal, leading to compromise of the spinal cord or nerve roots. This article provides an overview of the known etiology, pathogenesis, diagnostic algorithm, and treatment of thoracic spinal stenosis. MATERIALS AND METHODS: This paper is based on an overview of the literature from the past 25 years as well as the authors' own experience and results. RESULTS AND CONCLUSION: Thoracic spinal stenosis is a rare entity, for which the incidence is unknown. Pathoanatomically, the stenosis is caused by ligament or facet joint hypertrophy. Ventral stenosis can be caused by broad-based thoracic disc protrusion and ossification of the posterior longitudinal ligament (OPLL). Depending on location, main symptoms are pain and, in advanced cases, myelopathic symptoms which spare the upper extremities. Surgical decompression with or without instrumentation is the only treatment option. We present a cohort of 9 patients operated in a time frame of 7 years using a ventral approach, 89% of whom reported a substantial reduction in pain.


Asunto(s)
Osificación del Ligamento Longitudinal Posterior , Compresión de la Médula Espinal , Estenosis Espinal , Vértebras Torácicas/cirugía , Descompresión Quirúrgica , Humanos , Estenosis Espinal/etiología , Estenosis Espinal/patología , Estenosis Espinal/cirugía , Resultado del Tratamiento
4.
Dev Biol ; 426(2): 360-373, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27471010

RESUMEN

Unlike adult mammals, adult frogs regrow their optic nerve following a crush injury, making Xenopus laevis a compelling model for studying the molecular mechanisms that underlie neuronal regeneration. Using Translational Ribosome Affinity Purification (TRAP), a method to isolate ribosome-associated mRNAs from a target cell population, we have generated a transcriptional profile by RNA-Seq for retinal ganglion cells (RGC) during the period of recovery following an optic nerve injury. Based on bioinformatic analysis using the Xenopus laevis 9.1 genome assembly, our results reveal a profound shift in the composition of ribosome-associated mRNAs during the early stages of RGC regeneration. As factors involved in cell signaling are rapidly down-regulated, those involved in protein biosynthesis are up-regulated alongside key initiators of axon development. Using the new genome assembly, we were also able to analyze gene expression profiles of homeologous gene pairs arising from a whole-genome duplication in the Xenopus lineage. Here we see evidence of divergence in regulatory control among a significant proportion of pairs. Our data should provide a valuable resource for identifying genes involved in the regeneration process to target for future functional studies, in both naturally regenerative and non-regenerative vertebrates.


Asunto(s)
Proteínas del Ojo/biosíntesis , Regulación de la Expresión Génica , Regeneración Nerviosa/fisiología , Proteínas del Tejido Nervioso/biosíntesis , Traumatismos del Nervio Óptico/fisiopatología , Proteínas de Xenopus/biosíntesis , Xenopus laevis/genética , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Proteínas del Ojo/genética , Ontología de Genes , Anotación de Secuencia Molecular , Compresión Nerviosa , Proteínas del Tejido Nervioso/genética , ARN Mensajero/genética , ARN Mensajero/aislamiento & purificación , Células Ganglionares de la Retina/metabolismo , Ribosomas/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ARN , Homología de Secuencia de Aminoácido , Transducción de Señal , Proteínas de Xenopus/genética , Xenopus laevis/fisiología
5.
Support Care Cancer ; 23(12): 3465-72, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25791393

RESUMEN

BACKGROUND: Head and neck cancer (HNC) patients can experience symptoms due to the tumor itself or to the treatment, with an impact on health-related quality of life (HRQoL). Patient-reported outcome (PRO) measures pertaining to HRQoL are used in medical research and to support clinical decisions. PRO instrument applicability and cultural adaptation must be tested for each population. The aim of this study is to linguistically validate the Italian translation of the M.D. Anderson Symptom Inventory--Head and Neck Module (MDASI-HN). METHODS: Following forward and backward translation of the items of the English MDASI-HN into Italian, it was administered along with a cognitive debriefing to HNC patients able to read and understand Italian language. Individual and group responses are presented using descriptive statistics. RESULTS: From May 2013 through September 2013, 56 patients with HNC (18 during curative treatment, 20 in palliative chemotherapy, and 18 in follow-up period) completed the MDASI-HN followed by accompanying cognitive debriefing. Ninety-nine percent of the individual MDASI-HN items were completed. Average time to complete the MDASI-HN was 8.5 min (range 3-15). Results suggested overall ease of completion, relevance, and comprehensibleness of this translated self-report instrument in this Italian patient population. CONCLUSIONS: The Italian version of the MDASI-HN is linguistically valid; future research should explore dimensionality, reliability, and convergent, discriminant, and predictive validity of this patient-reported instrument, in order to use this translated version in outcomes research and clinical settings.


Asunto(s)
Neoplasias de Cabeza y Cuello/terapia , Lenguaje , Evaluación de Síntomas/métodos , Traducciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/patología , Humanos , Italia , Lingüística/métodos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/normas , Evaluación del Resultado de la Atención al Paciente , Calidad de Vida , Reproducibilidad de los Resultados , Autoinforme , Evaluación de Síntomas/normas , Evaluación de Síntomas/tendencias , Adulto Joven
6.
Eur J Pain ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38623029

RESUMEN

BACKGROUND AND OBJECTIVE: Recently, a consensus process specified a core outcome set (COS) of domains to be assessed in each comparative effectiveness research and clinical practice related to acute postoperative pain. Physical function (PF) was one of these domains. The aim of this review was to investigate which patient-reported outcome measures (PROMs) are used to assess PF after total knee arthroplasty (TKA) in clinical trials and if they fulfil basic requirements for a COS of PROMs based on their psychometric properties. METHODS: A systematic review of randomized controlled trials and observational studies based on a search in MEDLINE, EMBASE and CENTRAL was undertaken. PROMs and performance measures were extracted and investigated, including evaluation of psychometric properties of PROMs based on COSMIN recommendations. RESULTS: From initially 2896 identified records, 479 studies were included in the qualitative synthesis. Only 87 of these trials (18%) assessed PF using PROMs, whereas especially performance outcome measures were used in 470 studies (98%). Application of the 'COSMIN Risk-of-Bias-Box 1' to 13 of the 14 identified PROMs resulted in insufficient content validity of the included PROMs regarding the target population based on the inauguration or development articles. CONCLUSION: Our data indicate that a patient-centred postoperative assessment of PF in pain-related clinical trials early after TKA is not common, even though patient-reported assessment is widely recommended. In addition, none of the applied PROMs shows content validity based on their inauguration or development articles for the assessment of postoperative pain-related PF after TKA. SIGNIFICANCE: A systematic search for patient-reported outcome measures assessing postoperative, pain-related physical function after total knee arthroplasty in clinical trials and assessment of their content validity revealed none that fulfilled requirements based on COSMIN recommendations.

7.
Nat Mater ; 11(8): 690-3, 2012 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-22683821

RESUMEN

Replacing noble metals in heterogeneous catalysts by low-cost substitutes has driven scientific and industrial research for more than 100 years. Cheap and ubiquitous iron is especially desirable, because it does not bear potential health risks like, for example, nickel. To purify the ethylene feed for the production of polyethylene, the semi-hydrogenation of acetylene is applied (80 × 10(6) tons per annum; refs 1-3). The presence of small and separated transition-metal atom ensembles (so-called site-isolation), and the suppression of hydride formation are beneficial for the catalytic performance. Iron catalysts necessitate at least 50 bar and 100 °C for the hydrogenation of unsaturated C-C bonds, showing only limited selectivity towards semi-hydrogenation. Recent innovation in catalytic semi-hydrogenation is based on computational screening of substitutional alloys to identify promising metal combinations using scaling functions and the experimental realization of the site-isolation concept employing structurally well-ordered and in situ stable intermetallic compounds of Ga with Pd (refs 15-19). The stability enables a knowledge-based development by assigning the observed catalytic properties to the crystal and electronic structures of the intermetallic compounds. Following this approach, we identified the low-cost and environmentally benign intermetallic compound Al(13)Fe(4) as an active and selective semi-hydrogenation catalyst. This knowledge-based development might prove applicable to a wide range of heterogeneously catalysed reactions.

8.
J Heart Lung Transplant ; 40(5): 368-376, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33642140

RESUMEN

BACKGROUND: The size of the Fontan population with end-stage heart failure is growing. In this population, heart transplantation has been the only option. This study sought to investigate the efficacy of ventricular assist device (VAD) support in Fontan patients. METHODS: We conducted a retrospective study of Fontan patients in the Advanced Cardiac Therapies Improving Outcomes Network. We evaluated patient characteristics, and the clinical and physiologic outcomes after VAD implantation. RESULTS: We identified 45 Fontan patients implanted with VAD. The average age of patients was 10 years (interquartile range: 4.5-18) and 30% were female. The majority had a morphologic right ventricle (69%), moderate or greater ventricular dysfunction (83%), and moderate or greater atrioventricular valve regurgitation (65%). The majority of implants were as a bridge to transplantation (76%), and the majority of patients were Interagency Registry for Mechanically Assisted Circulatory Support Profile 2 (56%). The most commonly employed device was the Medtronic HeartWare HVAD (56%). A total of 13 patients were discharged on device support, and 67% of patients experienced adverse events, the most common of which were neurologic (25%). At 1 year after device implantation, the rate of transplantation was 69.5%, 9.2% of patients continued to be VAD supported, and 21.3% of patients had died. Hemodynamically, VAD was effective in decreasing both Fontan and ventricular end-diastolic pressures in some individuals. CONCLUSIONS: VAD is effective in supporting patients with end-stage Fontan failure awaiting heart transplantation. Future research should focus on identifying clinical and physiologic characteristics predictive of a favorable response to VAD support.


Asunto(s)
Procedimiento de Fontan , Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Sistema de Registros , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Trasplante de Corazón , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
9.
Ann Oncol ; 21(3): 608-614, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19880433

RESUMEN

BACKGROUND: Substantial numbers of cancer patients use complementary medicine therapies, even without a supportive evidence base. This study aimed to evaluate in a randomized controlled trial, the use of Medical Qigong (MQ) compared with usual care to improve the quality of life (QOL) of cancer patients. PATIENTS AND METHODS: One hundred and sixty-two patients with a range of cancers were recruited. QOL and fatigue were measured by Functional Assessment of Cancer Therapy-General and Functional Assessment of Cancer Therapy-Fatigue, respectively, and mood status by Profile of Mood State. The inflammatory marker serum C-reactive protein (CRP) was monitored serially. RESULTS: Regression analysis indicated that the MQ group significantly improved overall QOL (t(144) = -5.761, P < 0.001), fatigue (t(153) = -5.621, P < 0.001), mood disturbance (t(122) =2.346, P = 0.021) and inflammation (CRP) (t(99) = 2.042, P < 0.044) compared with usual care after controlling for baseline variables. CONCLUSIONS: This study indicates that MQ can improve cancer patients' overall QOL and mood status and reduce specific side-effects of treatment. It may also produce physical benefits in the long term through reduced inflammation.


Asunto(s)
Afecto , Ejercicios Respiratorios , Fatiga/terapia , Inflamación/terapia , Neoplasias/fisiopatología , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Evaluación de Resultado en la Atención de Salud , Pronóstico , Encuestas y Cuestionarios
10.
J Evol Biol ; 23(4): 805-16, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20210826

RESUMEN

Hybrid speciation is thought to be facilitated by escape of early generation hybrids into new habitats, subsequent environmental selection and adaptation. Here, we ask whether two homoploid hybrid plant species (Helianthus anomalus, H. deserticola) diverged sufficiently from their ancestral parent species (H. annuus, H. petiolaris) during hybrid speciation so that they are more fit than the parent species in hybrid species habitats. Hybrid and parental species were reciprocally transplanted into hybrid and parental habitats. Helianthus anomalus was more fit than parental species in the H. anomalus actively moving desert dune habitat. The abilities to tolerate burial and excavation and to obtain nutrients appear to be important for success in the H. anomalus habitat. In contrast, H. deserticola failed to outperform the parental species in the H. deserticola stabilized desert dune habitat, and several possible explanations are discussed. The home site advantage of H. anomalus is consistent with environmental selection having been a mechanism for adaptive divergence and hybrid speciation and supports the use of H. anomalus as a valuable system for further assessment of environmental selection and adaptive traits.


Asunto(s)
Ecosistema , Helianthus/genética , Hibridación Genética/fisiología , Adaptación Fisiológica/genética , Especiación Genética , Selección Genética
11.
J Minim Invasive Gynecol ; 22(6S): S134, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27678731
12.
Adv Exp Med Biol ; 669: 231-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20217355

RESUMEN

In 18 healthy age- and sex- matched controls and 13 patients with Wilsons disease (18-50 years) under continuous copper chelating therapy sinusoidal forearm movements of a given target rates (target rates: 0.2, 0.3, 0.4, 0.5, 0.6 Hz) as well as breathing movements were recorded by means of a goniometer and a breathing girdle in parallel. Additionally, controls and patients had to perform spontaneous forearm movements at their most comfortable rate. The percentage of time during which forearm and breathing movements were coupled was significantly reduced in the patients. With increasing target rate the mean breathing rate significantly increased in the controls but not in the patients. Furthermore, the variability of breathing rate significantly increased in the patients but not in the controls. These two factors probably caused that the coupling of breathing and extremity movements was significantly reduced in the patients.


Asunto(s)
Movimiento/fisiología , Música , Periodicidad , Respiración , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Degeneración Hepatolenticular/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
13.
New Phytol ; 183(3): 868-879, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19552693

RESUMEN

Habitats that differ in soil resource availability are expected to differ for selection on resource-related plant traits. Here, we examined spatial and temporal variation in phenotypic selection on leaf ecophysiological traits for 10 Helianthus populations, including two species of hybrid origin, Helianthus anomalus and Helianthus deserticola, and artificial hybrids of their ancestral parents. Leaf traits assessed were leaf size, succulence, nitrogen (N) concentration and water-use efficiency (WUE). Biomass and leaf traits of artificial hybrids indicate that the actively moving dune habitat of H. anomalus was more growth limiting, with lower N availability but higher relative water availability than the stabilized dune habitat of H. deserticola. Habitats differed for direct selection on leaf N and WUE, but not size or succulence, for the artificial hybrids. However, within the H. anomalus habitat, direct selection on WUE also differed among populations. Across years, direct selection on leaf traits did not differ. Leaf N was the only trait for which direct selection differed between habitats but not within the H. anomalus habitat, suggesting that nutrient limitation is an important selective force driving adaptation of H. anomalus to the active dune habitat.


Asunto(s)
Ecosistema , Helianthus/genética , Helianthus/fisiología , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Carácter Cuantitativo Heredable , Selección Genética , Biomasa , Hibridación Genética , Fenotipo , Dinámica Poblacional , Factores de Tiempo
14.
Science ; 267(5205): 1796-9, 1995 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-7892603

RESUMEN

A process has been developed for the in situ formation of the mineral phase of bone. Inorganic calcium and phosphate sources are combined to form a paste that is surgically implanted by injection. Under physiological conditions, the material hardens in minutes concurrent with the formation of dahllite. After 12 hours, dahllite formation was nearly complete, and an ultimate compressive strength of 55 megapascals was achieved. The composition and crystal morphology of the dahllite formed are similar to those of bone. Animal studies provide evidence that the material is remodeled in vivo. A novel approach to skeletal repair is being tested in human trials for various applications; in one of the trials the new biomaterial is being percutaneously placed into acute fractures. After hardening, it serves as internal fixation to maintain proper alignment while healing occurs.


Asunto(s)
Apatitas/química , Sustitutos de Huesos/química , Carbonato de Calcio/química , Fosfatos de Calcio/química , Animales , Cristalografía por Rayos X , Perros , Femenino , Fracturas Óseas/terapia , Humanos , Microscopía Electrónica , Persona de Mediana Edad , Modelos Químicos , Oseointegración , Conejos , Espectroscopía Infrarroja por Transformada de Fourier
15.
Science ; 364(6436)2019 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-30975859

RESUMEN

The neurobiological mechanisms underlying the induction and remission of depressive episodes over time are not well understood. Through repeated longitudinal imaging of medial prefrontal microcircuits in the living brain, we found that prefrontal spinogenesis plays a critical role in sustaining specific antidepressant behavioral effects and maintaining long-term behavioral remission. Depression-related behavior was associated with targeted, branch-specific elimination of postsynaptic dendritic spines on prefrontal projection neurons. Antidepressant-dose ketamine reversed these effects by selectively rescuing eliminated spines and restoring coordinated activity in multicellular ensembles that predict motivated escape behavior. Prefrontal spinogenesis was required for the long-term maintenance of antidepressant effects on motivated escape behavior but not for their initial induction.


Asunto(s)
Antidepresivos/farmacología , Espinas Dendríticas/efectos de los fármacos , Trastorno Depresivo/fisiopatología , Ketamina/farmacología , Corteza Prefrontal/efectos de los fármacos , Estrés Psicológico/fisiopatología , Sinapsis/efectos de los fármacos , Animales , Antidepresivos/uso terapéutico , Corticosterona/farmacología , Espinas Dendríticas/patología , Espinas Dendríticas/fisiología , Trastorno Depresivo/inducido químicamente , Trastorno Depresivo/tratamiento farmacológico , Modelos Animales de Enfermedad , Reacción de Fuga/efectos de los fármacos , Ketamina/uso terapéutico , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Plasticidad Neuronal/efectos de los fármacos , Corteza Prefrontal/patología , Corteza Prefrontal/fisiopatología , Estrés Psicológico/inducido químicamente , Sinapsis/fisiología
16.
Oncogene ; 26(26): 3846-56, 2007 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-17160014

RESUMEN

Serial analysis of gene expression followed by pathway analysis implicated the tight junction protein claudin-1 (CLDN1) in melanoma progression. Tight junction proteins regulate the paracellular transport of molecules, but staining of a tissue microarray revealed that claudin-1 was overexpressed in melanoma, and aberrantly expressed in the cytoplasm of malignant cells, suggesting a role other than transport. Indeed, melanoma cells in culture demonstrate no tight junction function. It has been shown that protein kinase C (PKC) can affect expression of claudin-1 in rat choroid plexus cells, and we observed a correlation between levels of activated PKC and claudin expression in our melanoma cells. To determine if PKC could affect the expression of CLDN1 in human melanoma, cells lacking endogenous claudin-1 were treated with 200 nM phorbol myristic acid (PMA). PKC activation by PMA caused an increase in CLDN1 transcription in 30 min, and an increase in claudin-1 protein by 12 h. Inhibition of PKC signaling in cells with high claudin-1 expression resulted in decreased claudin-1 expression. CLDN1 appears to contribute to melanoma cell invasion, as transient transfection of melanoma cells with CLDN1 increased metalloproteinase 2 (MMP-2) secretion and activation, and subsequently, motility of melanoma cells as demonstrated by wound-healing assays. Conversely, knockdown of CLDN1 by siRNA resulted in the inhibition of motility, as well as decreases in MMP-2 secretion and activation. These data implicate claudin-1 in melanoma progression.


Asunto(s)
Movimiento Celular/fisiología , Melanoma/patología , Proteínas de la Membrana/metabolismo , Invasividad Neoplásica/fisiopatología , Proteína Quinasa C/metabolismo , Western Blotting , Línea Celular Tumoral , Claudina-1 , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Metaloproteinasa 2 de la Matriz/metabolismo , Melanoma/metabolismo , Microscopía Confocal , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
17.
Neuron ; 11(2): 237-51, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8352941

RESUMEN

We have developed an exposed brain preparation for observing growth cone pathfinding behavior while performing in vivo pharmacological manipulations, and we used it to test whether Xenopus retinal growth cones need filopodia to navigate. Time-lapse video observation showed that cytochalasin B acted quickly and reversibly when applied; cytochalasin B-treated growth cones lacked filopodia, but had active lamellipodia and continued to advance slowly. Whereas normal retinotectal axons visualized with horseradish peroxidase turn caudally in the mid-diencephalon to reach the tectum, cytochalasin B-treated axons grew past the normal turning point and, instead, continued straight within the diencephalon. In dose-response experiments, pathfinding became abnormal in the same concentration range in which filopodia disappeared. These results suggest that filopodia are necessary for retinal growth cones to respond to guidance signals in the diencephalon.


Asunto(s)
Encéfalo/embriología , Embrión no Mamífero/fisiología , Neuronas/fisiología , Animales , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Citocalasina B/farmacología , Citocalasinas/farmacología , Relación Dosis-Respuesta a Droga , Vías Nerviosas/efectos de los fármacos , Neuronas/efectos de los fármacos , Factores de Tiempo , Xenopus laevis
18.
Endocrinology ; 149(10): 5097-106, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18566112

RESUMEN

Neurological deficits in the offspring caused by human maternal hypothyroxinemia are thought to be irreversible. To understand the mechanism responsible for these neurological alterations, we induced maternal hypothyroxinemia in pregnant rats. Behavior and synapse function were evaluated in the offspring of thyroid hormone-deficient rats. Our data indicate that, when compared with controls, hypothyroxinemic mothers bear litters that, in adulthood, show prolonged latencies during the learning process in the water maze test. Impaired learning capacity caused by hypothyroxinemia was consistent with cellular and molecular alterations, including: 1) lack of increase of phosphorylated c-fos on the second day of the water maze test; 2) impaired induction of long-term potentiation in response to theta-burst stimulation to the Schaffer collateral pathway in the area 1 of the hippocampus Ammon's horn stratum radiatum, despite normal responses for input/output experiments; 3) increase of postsynaptic density protein 95 (PSD-95), N-methyl-D-aspartic acid receptor subunit 1, and tyrosine receptor kinase B levels in brain extracts; and 4) significant increase of PSD-95 at the PSDs and failure of this molecule to colocalize with N-methyl-D-aspartic acid receptor subunit 1, as it was shown by control rats. Our findings suggest that maternal hypothyroxinemia is a harmful condition for the offspring that can affect key molecular components for synaptic function and spatial learning.


Asunto(s)
Trastornos del Conocimiento/fisiopatología , Hipotiroidismo/fisiopatología , Aprendizaje por Laberinto/fisiología , Complicaciones del Embarazo/fisiopatología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Tiroxina/deficiencia , Factores de Edad , Animales , Trastornos del Conocimiento/etiología , Homólogo 4 de la Proteína Discs Large , Femenino , Hipotiroidismo/complicaciones , Imidazoles , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Potenciación a Largo Plazo/fisiología , Masculino , Proteínas de la Membrana/metabolismo , Fosforilación , Embarazo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Percepción Espacial/fisiología , Sinapsis/fisiología , Tiroxina/sangre
19.
Clin Genet ; 73(5): 430-40, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18312448

RESUMEN

Progressive skeletal disease accounts for some of the most debilitating complications of type 1 Gaucher disease. In this 48-month, prospective, non-randomized, open-label study of the effect of enzyme replacement therapy on bone response, 33 imiglucerase-naïve patients (median age 43 years with one or more skeletal manifestations such as osteopenia, history of bone crisis, or other documented bone pathology) received imiglucerase 60 U/kg/2 weeks. Substantial improvements were observed in bone pain (BP), bone crises (BC), and bone mineral density (BMD). Improvements in BP were observed at 3 months (p < 0.001 vs baseline) and continued progressively throughout the study, with 39% of patients reporting pain at 48 months vs 73% at baseline. Eleven of the 13 patients with a pre-treatment history of BC had no recurrences. Biochemical markers for bone formation increased; markers for bone resorption decreased. Steady improvement of spine and femoral neck BMD, measured using dual-energy X-ray absorptiometry was noted. Mean Z score for spine increased from -0.72 +/- 1.302 at baseline to near-normal levels (-0.09 +/- 1.503) by month 48 (p = 0.042) and for femoral neck from -0.59 +/- 1.352 to -0.17 +/- 1.206 (p = 0.035) at month 36. This increase was sustained at 48 months. With imiglucerase treatment, patients should anticipate resolution of BC, rapid improvement in BP, increases in BMD, and decreased skeletal complications.


Asunto(s)
Densidad Ósea , Enfermedad de Gaucher/tratamiento farmacológico , Glucosilceramidasa/uso terapéutico , Columna Vertebral/metabolismo , Enfermedades Óseas , Enfermedades Óseas Metabólicas , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos
20.
Eur J Anaesthesiol ; 25(2): 97-105, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17894912

RESUMEN

BACKGROUND AND OBJECTIVE: Major gynaecological abdominal surgery is associated with moderate to severe postoperative pain, hyperalgesia and the need for multimodal analgesia to reduce high morphine consumption. A low-dose ketamine regimen appears to prevent postoperative hyperalgesia. We examined the potential beneficial effect of ketamine on postoperative pain management and cognitive function. METHODS: Ninety patients were included in this double-blind, randomized, placebo-controlled study to test the efficacy and adverse effects of ketamine (as an intraoperative bolus of 0.15 mg kg-1, followed postoperatively by ketamine 0.5 mg per morphine 1 mg in a patient-controlled analgesia device). All patients received additionally ketoprofen. The main end-point was morphine consumption over the first 24 h. Secondary efficacy and safety end-points were morphine consumption during the titration period and during the patient-controlled analgesia period (48 h), the number of morphine-related adverse effects and the results of psychometric tests. RESULTS: Ketamine, in combination with morphine and ketoprofen, did not improve postoperative pain scales and did not reduce morphine consumption and the incidence of morphine-related adverse effects. Ketamine did not modify mood, cognitive and memory functioning. CONCLUSION: Adding a low dose of ketamine to an efficacious multimodal analgesic regimen did not improve analgesia after gynaecological surgery. Although this combination appears to be safe, the lack of benefit suggests that a low dose of ketamine should not be used for routine care.


Asunto(s)
Afecto/efectos de los fármacos , Cognición/efectos de los fármacos , Procedimientos Quirúrgicos Ginecológicos , Ketamina/uso terapéutico , Memoria a Corto Plazo/efectos de los fármacos , Dolor Postoperatorio/tratamiento farmacológico , Adolescente , Adulto , Anciano , Analgesia Controlada por el Paciente , Analgésicos/efectos adversos , Analgésicos/uso terapéutico , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/efectos adversos , Antiinflamatorios no Esteroideos/administración & dosificación , Método Doble Ciego , Quimioterapia Combinada , Procedimientos Quirúrgicos Electivos , Femenino , Humanos , Ketamina/efectos adversos , Cetoprofeno/administración & dosificación , Persona de Mediana Edad , Morfina/administración & dosificación , Morfina/efectos adversos , Estudios Prospectivos , Psicometría/métodos , Psicometría/estadística & datos numéricos , Resultado del Tratamiento
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