RESUMEN
BACKGROUND: The postulated sites of perilymph fistulae involve otic capsule deficiencies, in particular, at the fissula ante fenestram. Histological studies have revealed this to be a channel extending from the middle ear, and becoming continuous with the inner ear medial to the anterior limit of the oval window. The relationship between a patent fissula and symptoms of perilymph fistula is contentious. OBJECTIVE: The understanding of the anatomy of the fissula ante fenestram is incomplete. Histopathology is inherently destructive to the delicate ultrastructure of the middle and inner ear. Conversely, X-ray microtomography allows non-destructive examination of the otic capsule. In this study, we used X-ray microtomography to characterise the fissula ante fenestram. MATERIALS AND METHODS: We imaged cadaveric temporal bones with X-ray microtomography. We used the Avizo Fire (Visualization Science Group, Merignac Cedex, France) software to perform post-processing and image analysis. RESULTS: Three-dimensional modelling of the fissula ante fenestram allowed stratification into four forms: rudimentary pit; partial fissula; complete occluded fissula; and complete patent fissula. CONCLUSION: X-ray microtomography showed that the fissula ante fenestram is present in various forms from rudimentary pit to complete deficiency of the otic capsule. This understanding may have implications for otologic surgery and clinical diagnosis of perilymph fistula.
Asunto(s)
Acueducto Coclear/diagnóstico por imagen , Acueducto Coclear/cirugía , Simulación por Computador , Oído Interno/diagnóstico por imagen , Oído Interno/cirugía , Fenestración del Laberinto , Fístula/diagnóstico por imagen , Fístula/cirugía , Imagenología Tridimensional , Enfermedades del Laberinto/diagnóstico por imagen , Enfermedades del Laberinto/cirugía , Canales Semicirculares/diagnóstico por imagen , Microtomografía por Rayos X , Adulto , Humanos , Interpretación de Imagen Asistida por Computador , Canales Semicirculares/cirugía , Programas InformáticosRESUMEN
BACKGROUND: The Lee Silverman Voice Treatment (LSVT®) was specifically created and tested to comply with the needs of individuals with Parkinson's disease (PD) and other neurological problems. This is a high effort intensive treatment that aims at increasing vocal intensity through the increase of subglottal air pressure, i.e. respiratory effort, for a better cordal adduction and vibration, following the motto "think loud". AIM: The main goal of this study is to inspect the efficacy of LSVT® treatment in progressive supranuclear palsy (PSP) patients. DESIGN: Longitudinal study. SETTING: Rehabilitative inpatient unit. POPULATION: Sixteen patients with PSP and 23 patients with idiopathic PD as control were enrolled in the study. METHODS: All patients underwent a training consisting in16 sessions of speech therapy following the LSVT® protocol. Initially the two groups of patients had similar voice problems, i.e. low volume and bad articulation of speech. RESULTS: A statistically significant improvement was found among the data collected before and after treatment in the PSP and Parkinson groups. Increase in maximum phonation duration and volume of voice in reading were similar in the two groups. Improvement in quality of voice and articulation were more significant in the PD group as compared to the PSP group. CONCLUSION: These results, along with previous findings, add further support to the generalized therapeutic impact of intensive voice treatment on respiratory and laryngeal functions in individuals with PSP. CLINICAL REHABILITATION IMPACT: The positive results, the absence of dropout and collateral effect following this clinical treatments with LSVT technique encouraged to use this technique in PSP patients.
Asunto(s)
Disartria/fisiopatología , Disartria/rehabilitación , Logopedia/métodos , Parálisis Supranuclear Progresiva/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Disartria/etiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/fisiopatología , Fonación , Medición de la Producción del Habla , Parálisis Supranuclear Progresiva/complicaciones , Resultado del TratamientoRESUMEN
BACKGROUND: At present there is no agreement on a common evaluation protocol to assess improvement in stroke patients after robotic therapy. AIM: The aim of this study was to identify a Minimum Data Set Assessment Protocol, using an agreement-based survey. DESIGN: A Delphi survey. SETTING: This study was conceived by the Italian Robotic Neurorehabilitation Research Group (IRNRG), an Italian group involved in the clinical application of robot-assisted rehabilitation devices POPULATION: Stroke subjects. METHODS: A 3-round Delphi survey was carried out through the electronic submission of questionnaires to a panel of experts identified in fourteen rehabilitation centers. For each generated item, experts were asked to rate questions on a 5 point Likert Scale. RESULTS: After the 1st round the questionnaire was filled out by 43 (84.3%) out of 51 experts invited to participate in the study. In the 2nd and 3rd rounds we explored the specific evaluation tools for each of the ICF domains identified in the 1st round. The experts identified the following assessment tools for the upper limb: the Ashworth Scale, the Fugl-Meyer assessment scale, the Frenchay Arm Test, the Medical Research Council scale, the Motricity Index, Frenchay Activities Index and Modified Barthel Index; and for the lower limb: the Ashworth Scale, the Motricity Index, the 10 meter walking Test, the 6 minutes walking Test, the Functional Ambulatory Classification, the Timed Up and Go Test, the Walking Handicap Scale, the Borg Rating of Perceived Exertion, the Heart Rate, the Medical Research Council Scale, the Tinetti Balance Scale and the Modified Barthel Index. CONCLUSION: The Delphi survey presented in this study allows the identification of a shared assessment protocol to be applied in clinical practice and research for the evaluation of the real improvement related to robot-assisted rehabilitation of the upper and lower limb in patients after stroke. CLINICAL REHABILITATION IMPACT: Clinicians and researchers could use the results of this study to obtain a common language in robotic rehabilitation assessments.
Asunto(s)
Técnica Delphi , Modalidades de Fisioterapia/instrumentación , Robótica/instrumentación , Rehabilitación de Accidente Cerebrovascular , Evaluación de la Discapacidad , Femenino , Humanos , Italia , Masculino , Recuperación de la Función , Encuestas y Cuestionarios , Resultado del TratamientoRESUMEN
AIM: To explore morphological or electrophysiological evidence for the presence of endolymphatic hydrops (EH) in guinea pig cochleae in the first 3 months after cochlear implantation. METHODS: Dummy silastic electrodes were implanted atraumatically into the basal turn of scala tympani via a cochleostomy. Round window electrocochleography (ECochG) was undertaken prior to and after implantation. Animals survived for 1, 7, 28 or 72 days prior to a terminal experiment, when ECochG was repeated. The cochleae were imaged using micro-CT after post-fixing with osmium tetroxide to reveal the inner ear soft tissue structure. EH was assessed by visual inspection at a series of frequency specific places along the length of the cochlea, and the extent to which Reissner's membrane departed from its neutral position was quantified. Tissue response volumes were calculated. Using ECochG, the ratio of the summating potential to the action potential (SP/AP ratio) was calculated in response to frequencies between 2 and 32 kHz. RESULTS: There was minimal evidence of electrode trauma from cochlear implantation on micro-CT imaging. Tissue response volumes did not change over time. EH was most prevalent 7 days after surgery in implanted ears, as determined by visual inspection. Scala media areas were increased, as expected in cases of EH, over the first month after cochlear implantation. SP/AP ratios decreased immediately after surgery, but were elevated 1 and 7 days after implantation. CONCLUSIONS: EH is prevalent in the first weeks after implant surgery, even in the absence of significant electrode insertion trauma.
Asunto(s)
Cóclea/cirugía , Implantación Coclear/efectos adversos , Hidropesía Endolinfática/etiología , Estimulación Acústica , Animales , Audiometría de Respuesta Evocada , Umbral Auditivo , Cóclea/diagnóstico por imagen , Cóclea/fisiopatología , Implantación Coclear/instrumentación , Implantes Cocleares , Modelos Animales de Enfermedad , Hidropesía Endolinfática/diagnóstico , Hidropesía Endolinfática/fisiopatología , Potenciales Evocados , Cobayas , Factores de Tiempo , Microtomografía por Rayos XRESUMEN
BACKGROUND: The gait of healthy elderly and of subjects with Parkinson's disease (PD) displays some common features, suggesting that PD may be a model of ageing. AIM: The aim of the study was to quantify highlight the differences and similarities between the gait patterns of young PD and healthy elderly, to uncover if PD could be assumed as a model of ageing. DESIGN: An optoelectronic system was used for 3D gait analysis evaluation. POPULATION AND METHODS: We compared the gait parameters of 15 young PD (YPD) with the gait of 32 healthy elderly subjects (ES) and 21 healthy subjects age-matched with the PD subjects. RESULTS. Common features between YPD and ES were majorly found in the parameters that reflect the presence of an unstable, uncertain gait, and of corrective strategies employed to reduce instability. On the other side, typical features were present in the gait patterns of PD subjects. CONCLUSION. Our study helped identifying some typical characteristics of the onset disease, and to unravel the symptoms of ageing from those of PD by comparing young PD subjects to elderly healthy subjects. CLINICAL REHABILITATION IMPACT: This allows a deeper understanding of the mechanisms underlying the gait in ageing and PD.
Asunto(s)
Envejecimiento , Trastornos Neurológicos de la Marcha/fisiopatología , Enfermedad de Parkinson/fisiopatología , Anciano , Estudios de Casos y Controles , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Difficulty in walking is a major feature of neurological disease, and loss of mobility is the activity of daily living on which patients place the greatest value. The impact on patients is enormous, with negative ramifications on their participation in social, vocational, and recreational activities. In current clinical practice the gait restoration with robotic device is an integral part of rehabilitation program. Robot therapy involves the use of a robot exoskeleton device or end-effector device to help the patient retrain motor coordination by performing well-focused and carefully directed repetitive practice. The exoskeleton, as an assistive device, is also an external structural mechanism with joints and links corresponding to those of the human body. These robots use joint trajectories of the entire gait cycle and offer a uniform (more or less) stiff control along this trajectory. In this field the new powered exoskeleton ReWalk (Argo Medical Technologies Ltd) was developed to have an alternative mobility solution to the wheelchair and rehabilitation treatment for individuals with severe walking impairments, enabling them to stand, walk, ascend/descent stairs and more. The end-effector-based robot is a device with footplates placed on a double crank and rocker gear system. Alternatives to powered exoskeletons are devices that use movable footplates to which the patient's feet are attached. All devices include some form of body weight support. Prominent goals in the field include: developing implementable technologies that can be easily used by patients, therapists, and clinicians; enhancing the efficacy of clinician's therapies and increasing the ease of activities in the daily lives of patients.
Asunto(s)
Trastornos Neurológicos de la Marcha/rehabilitación , Aparatos Ortopédicos , Robótica/instrumentación , Traumatismos de la Médula Espinal/rehabilitación , Rehabilitación de Accidente Cerebrovascular , Diseño de Equipo , Trastornos Neurológicos de la Marcha/etiología , Humanos , Traumatismos de la Médula Espinal/complicaciones , Accidente Cerebrovascular/complicacionesRESUMEN
Mirror neurons are a specific class of neurons that are activated and discharge both during observation of the same or similar motor act performed by another individual and during the execution of a motor act. Different studies based on non invasive neuroelectrophysiological assessment or functional brain imaging techniques have demonstrated the presence of the mirror neuron and their mechanism in humans. Various authors have demonstrated that in the human these networks are activated when individuals learn motor actions via execution (as in traditional motor learning), imitation, observation (as in observational learning) and motor imagery. Activation of these brain areas (inferior parietal lobe and the ventral premotor cortex, as well as the caudal part of the inferior frontal gyrus [IFG]) following observation or motor imagery may thereby facilitate subsequent movement execution by directly matching the observed or imagined action to the internal simulation of that action. It is therefore believed that this multi-sensory action-observation system enables individuals to (re) learn impaired motor functions through the activation of these internal action-related representations. In humans, the mirror mechanism is also located in various brain segment: in Broca's area, which is involved in language processing and speech production and not only in centres that mediate voluntary movement, but also in cortical areas that mediate visceromotor emotion-related behaviours. On basis of this finding, during the last 10 years various studies were carry out regarding the clinical use of action observation for motor rehabilitation of sub-acute and chronic stroke patients.
Asunto(s)
Neuronas Espejo/fisiología , Movimiento/fisiología , Red Nerviosa/fisiopatología , Rehabilitación de Accidente Cerebrovascular , Mapeo Encefálico , Humanos , Corteza Motora/fisiopatología , Desempeño Psicomotor , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatologíaRESUMEN
STUDY DESIGN: Prospective, multicenter follow-up (F-U) observational study. OBJECTIVES: To investigate the changes in participation and sports practice of people after spinal cord injury (SCI) and their impact on perceived quality of life (QoL). METHODS: The questionnaire investigated the health status and management of clinical conditions and attendance of social integration, occupation, autonomy, car driving, sentimental relationships and perceived QoL in a SCI population 4 years after the first rehabilitation hospitalization. RESULTS: Respondents were 403, 83.4% male; 39% was tetraplegic. At F-U, 42.1% worked and studied, 42.2% still held their jobs or studies, and 69% drove the car. In all, 77.2% had bowel continence and 40.4% urinary continence. The results showed that for the 68.2% of respondents, the attendance of friends, relatives and colleagues during their free time was the same or increased compared with the time before the injury, whereas 31.8% showed a decrease. The amount of time the 52.1% of respondents left home was the same or increased compared with before the trauma, whereas 50.6% of the respondents said that the time they were engaged in hobbies was either the same or increased. CONCLUSION: SCI people who perceived their QoL as being higher, and whose attendance, autonomy and time was increased in respect to hobbies, were mainly men with an age range between 36 and 40 years, unmarried, paraplegic and with A-B Asia Score. Regarding the amount of time dedicated to practicing sports, the only difference was the most of that respondents, who indicated a decrease, were women.
Asunto(s)
Pasatiempos , Relaciones Interpersonales , Calidad de Vida , Traumatismos de la Médula Espinal , Deportes , Adulto , Femenino , Estudios de Seguimiento , Pasatiempos/psicología , Pasatiempos/estadística & datos numéricos , Humanos , Masculino , Calidad de Vida/psicología , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/psicología , Deportes/psicología , Deportes/estadística & datos numéricos , Encuestas y CuestionariosRESUMEN
To examine the role of climatic extremes in structuring reef fish communities in the Arabian region, reef fish communities were visually surveyed at four sites within the southern Persian Gulf (also known as the Arabian Gulf and The Gulf), where sea-surface temperatures are extreme (range: 12-35° C annually), and these were compared with communities at four latitudinally similar sites in the biogeographically connected Gulf of Oman, where conditions are more moderate (range: 22-31° C annually). Although sites were relatively similar in the cover and composition of coral communities, substantial differences in the structure and composition of associated fish assemblages were apparent. Fish assemblages in the southern Persian Gulf held significantly lower estimates of abundance, richness and biomass, with significantly higher abundances of smaller sized individuals than Gulf of Oman assemblages. Functionally, southern Persian Gulf sites held significantly lower abundances of nearly all the common fish trophic guilds found on Gulf of Oman sites, although higher abundances of herbivorous grazers were apparent. These results suggest the potential for substantial changes in the structure of reef-associated fish communities, independent of changes in habitat within an environment of increasing fluctuations in oceanic climate.
Asunto(s)
Biodiversidad , Cambio Climático , Peces/fisiología , Animales , Arrecifes de Coral , Océano Índico , Densidad de PoblaciónRESUMEN
BACKGROUND: Various epidemiological studies explored cancer mortality and incidence among petrochemical workers. We followed up cancer incidence in a cohort of 5350 male petrochemical workers in the industrial area of Porto Torres (Sardinia, Italy). MATERIAL AND METHODS: The follow-up covered the period from 01/01/1990, when completeness of the cohort was certain and reference rates by the local Cancer Registry became available, up to 31/12/2006. Cohort members were subjects employed for six months or more in one of the chemical plants of the industrial area, alive as at 01/01/1990. Overall, a total of 81,392 person-years at risk were accumulated. The standardized incidence ratio (sir), as the ratio of observed to expected events, and its 95% confidence interval (CI) were calculated for all cancers and selected cancer sites, in the total cohort and in sub-cohorts of workers in plants where exposure to chemical agents evaluated in the IARC Monographs might have occurred. RESULTS: An increase in risk for all cancers was observed in the total cohort (596 cases; sir = 1.09; 95% CI 1.00-1.18), and it was highest for non-Hodgkin lymphoma (NHL, 26 cases: sir = 1.78; 95% CI 1.22-2.62). Risk for haemolymphatic cancer was highest in the sub-cohort of workers employed for 10 years or more, with a latency period of 20 years or longer, and among those employed in the manufacture and polymerization of vinyl chloride (VCM; all cancers, 51 cases: sir = 1.43; 95% CI 1.08-1.88; NHL, 4 cases: sir=4.06; 95% CI 1.64-10.0). Risk of haemolymphatic cancer was not significantly elevated in the sub-cohort potentially exposed to benzene. An excess risk of bladder cancer (RR = 1.46; 95% CI 1.09-1.96), but not of pleural cancer, was observed in the sub-cohort potentially exposed to asbestos. No significant increase in cancer risk was observed among workers potentially exposed to acrylonitrile, butadiene, or styrene. CONCLUSIONS: Our follow-up study of petrochemical workers showed an increase in risk for all cancers, and particularly NHL, apparently concentrated among workers potentially exposed to VCM
Asunto(s)
Industria Procesadora y de Extracción , Neoplasias/epidemiología , Enfermedades Profesionales/epidemiología , Estudios de Cohortes , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana EdadRESUMEN
The origin recognition complex (ORC) regulates DNA replication. However, some members of the ORC core, such as ORC3 and ORC5, have been implicated in neuronal maturation. In cultured cerebellar granule cells (CGCs), ORC3 mRNA and protein levels increased from 6 to 8days in vitro, a time that coincided with the maximal development of the dendritic arbor. In contrast, expression of ORC5 remained low throughout CGC maturation. Activation of type-4 metabotropic glutamate receptors with the selective enhancer, PHCCC, during a critical time-window (from 4 to 6days in vitro) anticipated the developmental peak of ORC3, increased the expression of two proteins associated with neuronal maturation, i.e. the mitogen-associated protein-2 (MAP-2) and postsynaptic density-95 (PSD-95), as well as dendritic length. siRNA-induced ORC3 knockdown reduced MAP-2 and PSD-95 expression on its own and abrogated the action of PHCCC. We examined whether the maturational effects of ORC3 were mediated by changes in the activity of the monomeric GTP-binding protein, Rho, which is known to regulate granule cell morphology. ORC3 knockdown increased the levels of the GTP-bound active form of Rho, whereas exposure to PHCCC reduced Rho activation. The action of PHCCC was largely attenuated in cultures deprived of ORC3. Finally, granule cell exposure to the Rho-associated kinase inhibitor, Y-27632, abolished the lowering effect of ORC3 knockdown on MAP-2 expression, and increased dendritic length. These data suggest that ORC3 supports neuronal maturation by inhibiting the Rho signaling pathway, and mediates the differentiating activity of mGlu4 receptors in cultured cerebellar granule cells.
Asunto(s)
Cerebelo/citología , Regulación del Desarrollo de la Expresión Génica/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Neuronas/fisiología , Complejo de Reconocimiento del Origen/metabolismo , Factores de Edad , Amidas/farmacología , Análisis de Varianza , Animales , Animales Recién Nacidos , Benzopiranos/farmacología , Dendritas/fisiología , Homólogo 4 de la Proteína Discs Large , Inhibidores Enzimáticos/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/genética , Proteínas Asociadas a Microtúbulos/genética , Neuronas/citología , Neuronas/efectos de los fármacos , Complejo de Reconocimiento del Origen/genética , Piridinas/farmacología , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , Ratas , Ratas Sprague-Dawley , Factor Rho/genética , Factor Rho/metabolismo , Factores de Tiempo , Transfección/métodosRESUMEN
BACKGROUND: The observation of actions performed by others activate in an observer the same neural structures (including mirror neurons) as when he/she actually performs the same actions. AIM: The aim of the present study was to assess whether action observation treatment may improve upper limb motor impairment in chronic stroke patients. DESIGN: This was an observational study. SETTING: Patients were recruited by three Italian Centres for Neurorehabilitation between 2006 and 2008. POPULATION: Twenty-eight chronic stroke patients with upper limb impairment have undergone for four weeks, five days a week, a rehabilitation treatment based on observation of video-clips presenting hand daily actions, followed by the imitation of those same actions with the affected limb. METHODS: Functional evaluation by means of Modified Barthel Index (MBI), Frenchay Arm Test (FAT) and Fugl Meyer (FM) was carried out twice before treatment (BT1 and BT2), at an interval of 15 days, then after treatment (AT1) and finally at a two-month follow-up (AT2). Wilcoxon Signed Rank test was applied to test differences between scores obtained from functional scales before and after treatment (BT1 vs. BT2; BT2 vs. AT1; AT1 vs. AT2). RESULTS: In all scales, scores did not differ when comparing BT1 with BT2. Scores improved significantly in all scales at AT1 as compared to BT2 (MBI, P=0.026; FAT, P=0.005; FM, P=0.001). This improvement was still present at the two-month follow-up as testified by no score difference between AT1 and AT2. CONCLUSION: Action Observation Treatment may become a useful strategy in the rehabilitation of stroke patients. CLINICAL REHABILITATION IMPACT: The present preliminary study suggests that stimulation of neural structures (including mirror neurons), activated when the patients actually perform the same actions as those observed could constitute a good alternative rehabilitative approach in chronic stroke patients.
Asunto(s)
Conducta Imitativa , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/fisiopatología , Extremidad Superior/fisiopatología , Actividades Cotidianas , Adolescente , Adulto , Anciano , Evaluación de la Discapacidad , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Observación , Estadísticas no ParamétricasRESUMEN
Neural stem cells (NSCs) isolated from the subventricular zone (SVZ) of postnatal mice, and cultured as neurospheres, expressed functional mGlu3 receptors. Following mitogen withdrawal and plating onto poly-ornitine-coated dishes, cells dissociated from the neurospheres differentiated into GFAP(+) astrocytes (about 85%), and a small percentage of beta-III tubulin(+)-neurons and O1(+)-oligodendrocytes. Activation of mGlu3 receptors with LY379268 (100 nM, applied every other day), during the differentiation period, impaired astrocyte differentiation, favoring the maintenance in culture of proliferating progenitors co-expressing GFAP with the immature markers, Sox1 and nestin. Co-treatment with the preferential mGlu2/3 receptor antagonist, LY341495 (100 nM), reversed this effect. We examined whether mGlu3 receptors could modulate the canonical signaling pathway activated by bone morphogenic proteins (BMPs), which are known to promote astrocyte differentiation of SVZ/NSCs. An acute challenge of cells isolated from the neurospheres with BMP4 (100 ng/mL) led to phosphorylation and nuclear translocation of the transcription factors, Smads. This effect was largely attenuated by the mGlu2/3 receptor agonist, LY379268. The interaction of mGlu3 and BMP4 receptors was mediated by the activation of the mitogen-activated protein kinase (MAPK) pathway. Accordingly, LY379268 failed to affect BMP receptor signaling when combined with the MAPK kinase inhibitor, UO-126 (30 muM). These data raise the intriguing possibility that glutamate regulates differentiation of SVZ/NSCs by activating mGlu3 receptors.
Asunto(s)
Astrocitos/metabolismo , Diferenciación Celular/fisiología , Linaje de la Célula/fisiología , Receptores de Glutamato Metabotrópico/metabolismo , Células Madre/metabolismo , Telencéfalo/metabolismo , Animales , Animales Recién Nacidos , Astrocitos/citología , Proteína Morfogenética Ósea 4/metabolismo , Proteína Morfogenética Ósea 4/farmacología , Receptores de Proteínas Morfogenéticas Óseas/agonistas , Receptores de Proteínas Morfogenéticas Óseas/metabolismo , Células Cultivadas , Agonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Proteína Ácida Fibrilar de la Glía/metabolismo , Ácido Glutámico/metabolismo , Proteínas de Filamentos Intermediarios/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Ratones , Proteínas del Tejido Nervioso/metabolismo , Nestina , Factores de Transcripción SOXB1/metabolismo , Proteínas Smad/metabolismo , Esferoides Celulares , Células Madre/citología , Telencéfalo/citologíaRESUMEN
Mutations in the PINK1 gene cause autosomal recessive Parkinson's disease. The PINK1 gene encodes a protein kinase that is mitochondrially cleaved to generate two mature isoforms. In addition to its protective role against mitochondrial dysfunction and apoptosis, PINK1 is also known to regulate mitochondrial dynamics acting upstream of the PD-related protein Parkin. Recent data showed that mitochondrial Parkin promotes the autophagic degradation of dysfunctional mitochondria, and that stable PINK1 silencing may have an indirect role in mitophagy activation. Here we report a new interaction between PINK1 and Beclin1, a key pro-autophagic protein already implicated in the pathogenesis of Alzheimer's and Huntington's diseases. Both PINK1 N- and C-terminal are required for the interaction, suggesting that full-length PINK1, and not its cleaved isoforms, interacts with Beclin1. We also demonstrate that PINK1 significantly enhances basal and starvation-induced autophagy, which is reduced by knocking down Beclin1 expression or by inhibiting the Beclin1 partner Vps34. A mutant, PINK1(W437X), interaction of which with Beclin1 is largely impaired, lacks the ability to enhance autophagy, whereas this is not observed for PINK1(G309D), a mutant with defective kinase activity but unaltered ability to bind Beclin1. These findings identify a new function of PINK1 and further strengthen the link between autophagy and proteins implicated in the neurodegenerative process.
Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia , Proteínas de la Membrana/metabolismo , Proteínas Quinasas/metabolismo , Proteínas Reguladoras de la Apoptosis/análisis , Beclina-1 , Línea Celular Tumoral , Células HeLa , Humanos , Proteínas de la Membrana/análisis , Mitocondrias/química , Mitocondrias/ultraestructura , Mutación , Proteínas Quinasas/análisis , Proteínas Quinasas/genética , Eliminación de Secuencia , Técnicas del Sistema de Dos HíbridosRESUMEN
Dendritic cells (DCs) are able to orchestrate innate and acquired immunity and can activate and sustain a long-lasting anti-tumor immune response in vivo when used as anti-tumor cell therapy. The selection of the antigen and the choice of its formulation are key points in designing anti-cancer DC-based vaccines. Cell released vesicles/exosomes have been shown to transfer antigens, HLAI/peptide complexes and co-stimulatory molecules to recipient cells. In this study we describe the generation of an allogenic microvesicle cell factory in which the expression of a specific tumor antigen was combined to the expression of co-stimulatory and allogeneic molecules. The DG75 lymphoblastoid cell line was selected as microvesicle producer and transfected with ErbB2, as tumor antigen prototype. The shed microvesicles transferred antigenic components to recipient DCs, increasing their immunogenicity. DC pulsing resulted in cross-presentation of ErbB2 both in HLAI and HLAII compartments, and ErbB2-specific CD8+ T cells from cancer patients were activated by DCs pulsed with vesicle-bound ErbB2. The microvesicle cell factory proposed may represent a source of cell free immunogen to be used for DC-based cancer therapy.
Asunto(s)
Antígenos de Neoplasias/inmunología , Neoplasias de la Mama/terapia , Linfocitos T CD8-positivos/inmunología , Células Dendríticas/trasplante , Inmunoterapia Adoptiva , Activación de Linfocitos , Receptor ErbB-2/inmunología , Vesículas Transportadoras/trasplante , Antígenos de Neoplasias/genética , Neoplasias de la Mama/inmunología , Línea Celular , Células Dendríticas/inmunología , Femenino , Antígenos HLA/inmunología , Humanos , Inmunofenotipificación , Interferón gamma/metabolismo , Receptor ErbB-2/genética , Transfección , Vesículas Transportadoras/inmunologíaRESUMEN
The molecular mechanism by which the lipido-sterolic extract of Serenoa repens (LSESr, Permixon) affects prostate cells remains to be fully elucidated. In androgen-independent PC3 prostate cancer cells, the LSESr-induced effects on proliferation and apoptosis were evaluated by counting cells and using a FACScan cytofluorimeter. PC3 cells were stained with JC-1 dye to detect mitochondrial membrane potential. Cell membrane lipid composition was evaluated by thin layer chromatography and gas chromatographic analysis. Akt phosphorylation was analyzed by Western blotting and cellular ultrastructure through electron microscopy. LSESr (12.5 and 25 microg/ml) administration exerted a biphasic action by both inhibiting proliferation and stimulating apoptosis. After 1 h, it caused a marked reduction in the mitochondrial potential, decreased cholesterol content and modified phospholipid composition. A decrease in phosphatidylinositol-4,5-bisphosphate (PIP2) level was coupled with reduced Akt phosphorylation. After 24 h, all of these effects were restored to pre-treatment conditions; however, the saturated (SFA)/unsaturated fatty acid (UFA) ratio increased, mainly due to a significant decrease in omega 6 content. The reduction in cholesterol content could be responsible for both membrane raft disruption and redistribution of signaling complexes, allowing for a decrease of PIP2 levels, reduction of Akt phosphorylation and apoptosis induction. The decrease in omega 6 content appears to be responsible for the prolonged and more consistent increase in the apoptosis rate and inhibition of proliferation observed after 2-3 days of LSESr treatment. In conclusion, LSESr administration results in complex changes in cell membrane organization and fluidity of prostate cancer cells that have progressed to hormone-independent status.
Asunto(s)
Antagonistas de Andrógenos/farmacología , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Preparaciones de Plantas/farmacología , Neoplasias de la Próstata , Serenoa/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral/citología , Línea Celular Tumoral/efectos de los fármacos , Membrana Celular/química , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Lípidos de la Membrana/química , Lípidos de la Membrana/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/fisiología , Fitoterapia , Preparaciones de Plantas/química , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
Targeted-therapies enhancing differentiation of glioma-initiating cells (GICs) are potential innovative approaches to the treatment of malignant gliomas. These cells support tumour growth and recurrence and are resistant to radiotherapy and chemotherapy. We have found that GICs express mGlu3 metabotropic glutamate receptors. Activation of these receptors sustained the undifferentiated state of GICs in culture by negatively modulating the action of bone morphogenetic proteins, which physiologically signal through the phosphorylation of the transcription factors, Smads. The cross-talk between mGlu3 receptors and BMP receptors was mediated by the activation of the mitogen-activated protein kinase pathway. Remarkably, pharmacological blockade of mGlu3 receptors stimulated the differentiation of cultured GICs into astrocytes, an effect that appeared to be long lasting, independent of the growth conditions, and irreversible. In in vivo experiments, a 3-month treatment with the brain-permeant mGlu receptor antagonist, LY341495 limited the growth of infiltrating brain tumours originating from GICs implanted into the brain parenchyma of nude mice. While clusters of tumour cells were consistently found in the brain of control mice, they were virtually absent in a large proportion of mice treated with LY341495. These findings pave the way to a new non-cytotoxic treatment of malignant gliomas based on the use of mGlu3 receptor antagonists.
Asunto(s)
Receptores de Proteínas Morfogenéticas Óseas/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Receptores de Glutamato Metabotrópico/fisiología , Transducción de Señal/fisiología , Aminoácidos/farmacología , Animales , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/fisiopatología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Agonistas de Aminoácidos Excitadores/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Glioma/tratamiento farmacológico , Glioma/patología , Glioma/fisiopatología , Humanos , Imagen por Resonancia Magnética , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Fosforilación/efectos de los fármacos , Receptores de Glutamato Metabotrópico/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Xantenos/farmacologíaRESUMEN
Chlamydophila pneumoniae has been implicated in atherosclerosis, but the role of this obligate intracellular pathogen in the development of the above pathology is still unclear. In particular, its presence and quantitative distribution within lesional areas has not yet been defined. We studied 18 carotid biopsies obtained from patients undergoing endoartherectomy. By laser microdissection (LCM), two different sites (intra-plaque and plaque-adjacent areas) were taken from each lesion, and the presence and quantity of the pathogen DNA were determined by real-time polymerase chain reaction (Real-time PCR). A total of 8 plaques, exclusively from patients with unstable angina, were positive in real-time PCR. The bacterial DNA was detected in both lesional areas of 3 plaques which contained the highest number of DNA copies (1,900 to 2,200 copy numbers), while C. pneumoniae DNA was detected only in the intra-plaque area of the other 5 positive (500 to 1,600 copy numbers). No C. pneumoniae DNA was found in the other 10 plaques of which 6 were from patients with unstable angina and 4 from stable angina patients. No DNA from Helicobacter pylori or Cytomegalovirus was found in any plaque. This is the first report where both the target lesion and an adjacent reference site were evaluated for the presence of C. pneumoniae DNA by the combination of LCM and Real-time PCR assays. The integration of these two methodologies offer an excellent tool for in situ studies and may help to elucidate the putative role of C. pneumoniae in atherosclerosis.
Asunto(s)
Aterosclerosis/microbiología , Infecciones por Chlamydia/microbiología , Chlamydophila pneumoniae/química , ADN Bacteriano/análisis , Microdisección/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Anciano , Aterosclerosis/patología , Arterias Carótidas/microbiología , Arterias Carótidas/patología , Infecciones por Chlamydia/patología , Chlamydophila pneumoniae/genética , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Endarterectomía Carotidea , Femenino , Humanos , Rayos Láser , Masculino , Persona de Mediana EdadRESUMEN
Mouse embryonic stem (ES) cells were stimulated to differentiate either as adherent monolayer cultures in DMEM/F12 supplemented with N2/B27, or as floating embryoid bodies (EBs) exposed to 1 microM retinoic acid (RA) for 4 days, starting from 4 DIV, and subsequently re-plated in DMEM/F12 medium. Adherent monolayer cultures of ES cells expressed mGlu5 receptors throughout the entire differentiation period. Selective pharmacological blockade of mGlu5 receptors with methyl-6-(phenylethynyl)-pyridine (MPEP) (1 microM, added once a day) accelerated the appearance of the neuronal marker, beta-tubulin. In addition, treatment with MPEP increased the number of cells expressing glutamate decarboxylase-65/67 (GAD(65/67)), a marker of GABAergic neurons. In floating EBs, mGlu5 receptors are progressively replaced by mGlu4 receptors. The orthosteric mGlu4/6/7/8 receptor agonist, L-2-amino-4-phosphonobutanoate (L-AP4), or the selective mGlu4 receptor enhancer, PHCCC,--both combined with RA at concentrations of 30 microM--increased the expression of both beta-tubulin and GAD(65/67), inducing the appearance of fully differentiated neurons that released GABA in response to membrane depolarization. We conclude that mGlu receptor subtypes regulate neuronal differentiation of ES cells in a context-dependent manner, and that subtype-selective ligands of these receptors might be used for the optimization of in vitro protocols aimed at producing GABAergic neurons from ES cells.
Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/metabolismo , Neuronas/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Aminobutiratos/farmacología , Animales , Benzopiranos/farmacología , Adhesión Celular , Diferenciación Celular/efectos de los fármacos , Línea Celular , Células Madre Embrionarias/efectos de los fármacos , Células Madre Embrionarias/enzimología , Antagonistas de Aminoácidos Excitadores/farmacología , Glutamato Descarboxilasa/metabolismo , Potenciales de la Membrana , Ratones , Neuronas/efectos de los fármacos , Neuronas/enzimología , Fenotipo , Piridinas/farmacología , Receptor del Glutamato Metabotropico 5 , Receptores de Glutamato Metabotrópico/efectos de los fármacos , Factores de Tiempo , Tretinoina/farmacología , Tubulina (Proteína)/metabolismoRESUMEN
Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef-associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled-up management intervention and decisive action on global emissions are required if the loss of coral-dominated ecosystems is to be avoided.