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Early prediction of the final size of any epidemic and in particular for Zika disease outbreaks can be useful for health authorities in order to plan the response to the outbreak. The Richards model is often been used to estimate epidemiological parameters for arboviral diseases based on the reported cumulative cases in single- and multi-wave outbreaks. However, other non-linear models can also fit the data as well. Typically, one follows the so called post selection estimation procedure, i.e., selects the best fitting model out of the set of candidate models and ignores the model uncertainty in both estimation and inference since these procedures are based on a single model. In this paper we focus on the estimation of the final size and the turning point of the epidemic and conduct a real-time prediction for the final size of the outbreak using several non-linear models in which these parameters are estimated via model averaging. The proposed method is applied to Zika outbreak data in four cities from Colombia, during the outbreak ocurred in 2015-2016.
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Brotes de Enfermedades , Modelos Teóricos , Infección por el Virus Zika/epidemiología , Virus Zika/fisiología , Ciudades/epidemiología , Colombia/epidemiología , Humanos , Incidencia , Dinámicas no Lineales , Infección por el Virus Zika/virologíaRESUMEN
The search in two-dimensional condensed matter systems of Rashba-type spin-polarized electronic states is aimed by the possibility to control and manipulate the spin orientation. In this Letter, for the first time, we report on the experimental evidence of a Rashba-type spin splitting in the n=1 image potential state. The image potential state Rashba splitting here measured at the graphene/Ir(111) interface, as confirmed by theoretical considerations, can be detectable to any metal surface with a significant spin-orbit coupling.
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AIMS/HYPOTHESIS: Knowledge of number, size and content of insulin secretory granules is pivotal for understanding the physiology of pancreatic beta cells. Here we re-evaluated key structural features of rat beta cells, including insulin granule size, number and distribution as well as cell size. METHODS: Electron micrographs of rat beta cells fixed either chemically or by high-pressure freezing were compared using a high-content analysis approach. These data were used to develop three-dimensional in silico beta cell models, the slicing of which would reproduce the experimental datasets. RESULTS: As previously reported, chemically fixed insulin secretory granules appeared as hollow spheres with a mean diameter of â¼350 nm. Remarkably, most granules fixed by high-pressure freezing lacked the characteristic halo between the dense core and the limiting membrane and were smaller than their chemically fixed counterparts. Based on our analyses, we conclude that the mean diameter of rat insulin secretory granules is 243 nm, corresponding to a surface area of 0.19 µm(2). Rat beta cells have a mean volume of 763 µm(3) and contain 5,000-6,000 granules. CONCLUSIONS/INTERPRETATION: A major reason for the lower mean granule number/rat beta cell relative to previous accounts is a reduced estimation of the mean beta cell volume. These findings imply that each granule contains about twofold more insulin, while its exocytosis increases membrane capacitance about twofold less than assumed previously. Our integrated approach defines new standards for quantitative image analysis of beta cells and could be applied to other cellular systems.
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Gránulos Citoplasmáticos/ultraestructura , Células Secretoras de Insulina/ultraestructura , Insulina/metabolismo , Vesículas Secretoras/ultraestructura , Animales , Células Cultivadas , Gránulos Citoplasmáticos/metabolismo , Femenino , Células Secretoras de Insulina/metabolismo , Microscopía Electrónica de Transmisión , Ratas , Ratas Wistar , Vesículas Secretoras/metabolismoRESUMEN
AIM: This work reports the analysis of the relationship between inferior fronto-occipital fasciculus (IFO), neoplastic lesions and surgical resection, in patients operated for gliomas located in the frontal, temporal and insular lobes of the dominant hemisphere. Aim of the study is evaluating the predictive value of inferior fronto-occipital fasciculus DTI-fiber tracking (FT) for determining the extent of resection preoperatively. METHODS: We selected 38 cases affected by lesions located in the frontal, temporal and insular lobes of the dominant hemisphere, which were related to the trajectory of the IFO. For each patient preoperative and postoperative MR images and DTI-FT were loaded into the neuronavigation system and merged; volumetric scan analysis was used for establishing tumor location and topography, as well as the volume of the lesion and of the residual tumor. All preoperative fiber tracking datasets were evaluated and the position of the tract (IFO) compared to the tumor was recorded. Postoperative MR scans were then compared with DTI-FT, in order to evaluate the correspondence between the resection boundaries and the trajectory of the fiber tract. RESULTS: Amongst the cases in which the IFO was inside the lesion, we found only incomplete resections (5 subtotal and 6 partial resections), while considering the cases in which the IFO was located outside the tumor, it was possible to perform a relevant (total/subtotal) resection in 18 of them (78%). CONCLUSION: FT of the inferior frontal-occipital fasciculus predicts the possibility and the extent of the resection for a frontal, temporal and/or insular lesion of the dominant hemisphere.
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Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Corteza Cerebral/cirugía , Glioma/patología , Glioma/cirugía , Adulto , Corteza Cerebral/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Valor Predictivo de las PruebasRESUMEN
Low-grade gliomas are slow growing intrinsic lesions that induces a progressive functional reshaping of the brain. Surgical removal of these lesions requires the combined efforts of a multidiscipinary team of neurosurgeon, neuroradiologist, neuropsychologist, neurophysiologist, and neurooncologists that all together contribute in the definition of the location, extension, and extent of functional involvement that a specific lesion has induced in a particular patient. Each tumor has induced particular and specific changes of the functional network, that varies among patients. This requires that each treatment plan should be tailored to the tumor and to the patient. When this is reached, surgery should be accomplished according to functional and anatomical boundaries, and has to aim to the maximal resection with the maximal patient functional preservation. This can be reached at the time of the initial surgery, depending on the functional organization of the brain, or may require additional surgeries, eventually intermingled with adjuvant treatments. The use of so called brain mapping techniques extend surgical indications, improve extent of resection with greater oncological impact, minimization of morbidity and increase in quality of life. To achieve the goal of a satisfactory tumor resection associated with the full preservation of the patients abilities, a series of neuropsychological, neurophysiological, neuroradiological and intraoperative investigations have to be performed. In this chapter, we will describe the rationale, the indications and the modality for performing a safe and rewarding surgical removal of low-grade gliomas by using these techniques, as well as the functional and oncological results.
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Neoplasias Encefálicas/cirugía , Glioma/cirugía , Microcirugia , Procedimientos Neuroquirúrgicos , Mapeo Encefálico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/fisiopatología , Glioma/patología , Glioma/fisiopatología , HumanosRESUMEN
We report on the design, construction, and performance of a compact magnetic shield that facilitates a controlled, low-noise environment for experiments with ultracold atomic gases. The shield was designed to passively attenuate external slowly varying magnetic fields while allowing for ample optical access. The geometry, number of layers, and choice of materials were optimized using extensive finite-element numerical simulations. The measured performance of the shield is in good agreement with the simulations. From measurements of the spin coherence of an ultracold atomic ensemble, we demonstrate a residual field noise of 2.6 µG and a suppression of external dc magnetic fields by more than five orders of magnitude.
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AIM: Surgery for gliomas located inside or in proximity of motor cortex or tracts requires cortical and subcortical mapping to locate motor function; direct electrical stimulation of brain cortex or subcortical pathways allows identification and preservation of motor function. In this study we evaluated the effect which subcortical motor mapping had on postoperative morbidity and extent of resection in a series of patients with gliomas involving motor areas or pathways. METHODS: One hundred and forty-six patients were included in the study. Intraoperative findings of primary motor cortex or subcortical tracts were reported, together with incidence of new postoperative deficits at short (1 week) and long term (1 month) examination. The relationship between intraoperative identification of subcortical motor tracts and extent of resection was reported. RESULTS: The motor strip was found in 133 patients (91%) and subcortical motor tracts in 91 patients (62.3%). New immediate postoperative motor deficits were documented in 59.3% of patients in whom a subcortical motor tract was identified intra-operatively and in 10.9% of those in whom subcortical tracts were not observed; permanent deficits were observed in 6.5% and 3.5%, respectively. A total resection was achieved in 94.4% of patients with high-grade gliomas and in 46.1% of those with low-grade gliomas.
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Mapeo Encefálico/métodos , Neoplasias Encefálicas/diagnóstico , Vías Eferentes/fisiopatología , Glioma/diagnóstico , Corteza Motora/fisiopatología , Complicaciones Posoperatorias/prevención & control , Adulto , Anciano , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Vías Eferentes/patología , Vías Eferentes/cirugía , Estimulación Eléctrica/métodos , Electrodiagnóstico/métodos , Electroencefalografía/métodos , Glioma/patología , Glioma/cirugía , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos , Corteza Motora/patología , Corteza Motora/cirugía , Trastornos del Movimiento/prevención & control , Procedimientos Neuroquirúrgicos/efectos adversos , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Neuroquirúrgicos/mortalidad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Resultado del TratamientoRESUMEN
Neuronal death, which follows ischemic injury or is triggered by excitotoxins, can occur by both apoptosis and necrosis. Caspases, which are not directly required for necrotic cell death, are central mediators of the apoptotic program. Here we demonstrate that caspases cleave and inactivate the plasma membrane Ca(2+) pump (PMCA) in neurons and non-neuronal cells undergoing apoptosis. PMCA cleavage impairs intracellular Ca(2+) handling, which results in Ca(2+) overload. Expression of non-cleavable PMCA mutants prevents the disturbance in Ca(2+) handling, slows down the kinetics of apoptosis, and markedly delays secondary cell lysis (necrosis). These findings suggest that caspase-mediated cleavage and inactivation of PMCAs can lead to necrosis, an event that is reduced by caspase inhibitors in brain ischemia.
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Apoptosis/fisiología , ATPasas Transportadoras de Calcio/metabolismo , Caspasas/metabolismo , Membrana Celular/enzimología , Hipoxia-Isquemia Encefálica/enzimología , Necrosis , Neuronas/enzimología , Animales , Animales Recién Nacidos , Apoptosis/efectos de los fármacos , Sitios de Unión/efectos de los fármacos , Sitios de Unión/fisiología , Células CHO , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , ATPasas Transportadoras de Calcio/efectos de los fármacos , Caspasa 3 , Caspasas/efectos de los fármacos , Caspasas/genética , Proteínas de Transporte de Catión , Membrana Celular/efectos de los fármacos , Células Clonales/citología , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Colorantes , Cricetinae , Hipoxia-Isquemia Encefálica/patología , Hipoxia-Isquemia Encefálica/fisiopatología , Inmunohistoquímica , Líquido Intracelular/metabolismo , Ratones , Mutación/efectos de los fármacos , Mutación/genética , Neuronas/efectos de los fármacos , Neuronas/patología , Neurotoxinas/farmacología , ATPasas Transportadoras de Calcio de la Membrana Plasmática , RatasRESUMEN
Recent work has shown that execution of the apoptotic program involves a relatively limited number of pathways. According to a general view, these would converge to activate the caspase family of proteases. However, there is increasing evidence that apoptotic-like features can be found also when cells are treated with inhibitors of caspases as the cell permeable tripeptide, Z-Val-Ala-Asp-fluoro-methyl-ketone (Z-VAD-fmk), or analogous compounds. This has posed the question as to whether apoptosis may occur in a caspase independent way, and whether caspase inhibitors may then be used to treat diseases characterised by an excess apoptosis. It is also becoming clear, that ATP depletion during the early phases of apoptosis can preclude caspase activation, and consequently switch execution of cell death towards necrosis. In vivo, a block or partial inhibition of the typical apoptotic demise may have profound implications, as persistence of damaged but "undead" cells within the nervous system, followed by delayed lysis may favour neuroinflammatory reactions. In this review, we discuss some recent findings, which suggest that cells may use diverging execution pathways, with different implications in neuropathology and therapy.
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Caspasas/metabolismo , Metabolismo Energético/fisiología , Neuronas/fisiología , Animales , Muerte Celular/fisiología , Activación Enzimática/fisiologíaRESUMEN
The pathogenesis of some neurodegenerative disorders has been linked to excitotoxicity, excess generation of nitric oxide (NO) and apoptosis. Here, we used a model of NO-triggered neuronal apoptosis that was strictly dependent on autocrine NMDA receptor (NMDA-R) activation and intracellular Ca2+ increase. We investigated the efficiency and potentially beneficial effects of calpain inhibition. Three calpain inhibitors that prevented intracellular fodrin proteolysis also blocked apoptotic features such as decrease in mitochondrial membrane potential, chromatin breakdown, and subsequent death of cerebellar granule neurons exposed to NO donors (S-nitroso-L-glutathione, S-nitroso-N-acetyl-d,l-penicillamine, and diethylamino-diazenolate-2-oxide). Since inhibitors did not interfere with NMDA-R activation, we suggest that block of calpains blunts NO-triggered neuronal apoptosis by stopping the cascade downstream of primary autocrine excitotoxic events.
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Apoptosis/efectos de los fármacos , Comunicación Autocrina/efectos de los fármacos , Calpaína/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Neuronas/efectos de los fármacos , Óxido Nítrico/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Animales , Apoptosis/fisiología , Comunicación Autocrina/fisiología , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Calpaína/metabolismo , Proteínas Portadoras/metabolismo , Células Cultivadas , Daño del ADN/efectos de los fármacos , Daño del ADN/fisiología , Relación Dosis-Respuesta a Droga , Antagonistas de Aminoácidos Excitadores/farmacología , Ratones , Ratones Endogámicos , Proteínas de Microfilamentos/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/fisiopatología , Neuronas/metabolismo , Neurotoxinas/farmacología , Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/farmacología , Receptores de N-Metil-D-Aspartato/metabolismoRESUMEN
Features of the spike afterhyperpolarization (AHP) recorded intracellularly have been analyzed in fast pyramidal tract neurons of cats. Cell input conductance increases during the AHP, possibly because of a change in potassium conductance, as suggested by an AHP equilibrium potential 10--15 mV negative to the resting membrane potential. When more spikes are evoked in succession, AHPs following the first one are strongly reduced in amplitude. The effect is virtually maximal (30--50% of the control) after a single spike and fades out by 200-400 ms after the last spike. At short interspike intervals the initial time course of the depression is hidden by summation occurring between consecutive AHPs.
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Potenciales Evocados , Tractos Piramidales/fisiología , Animales , Gatos , Permeabilidad de la Membrana Celular , Conductividad Eléctrica , Potasio/metabolismoRESUMEN
The aetiological model of depression proposed by Brown and Harris in 1978 was examined in a sample of 120 women in Milan, using the same method for the assessment of life stresses. The role of provoking agents (severe events and major difficulties) was found to be similar to that of the earlier study. There was some evidence that lack of an intimate relationship with a husband or a boyfriend acted as a vulnerability factor, increasing the risk of depression in the face of provoking agents. The overall results support the Brown-Harris aetiological model in a quite different cultural setting.
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Trastorno Depresivo/etiología , Acontecimientos que Cambian la Vida , Adolescente , Adulto , Anciano , Cultura , Trastorno Depresivo/epidemiología , Trastorno Depresivo/psicología , Empleo , Femenino , Humanos , Relaciones Interpersonales , Entrevistas como Asunto , Italia/epidemiología , Estudios Longitudinales , Matrimonio/psicología , Persona de Mediana Edad , Modelos Psicológicos , Proyectos de Investigación , Factores de Riesgo , Autorrevelación , Factores Sexuales , Estrés Psicológico/complicaciones , Estrés Psicológico/psicologíaRESUMEN
A group of patients undergoing aortic replacement of thoracic and abdominal aneurysms were studied by intraoperative recording of Somatosensory Evoked Potentials (SEPs). Lower limb nerves were stimulated and SEPs recorded at spinal and cortical level. Progressive changes of cortical SEPs until their disappearance were observed. In operations on the thoracic aorta, the spinal response was essentially unmodified, so that the observed alterations reflected true dysfunction of the spinal cord. The only patient who developed an intraoperative anterior spinal infarct had the longest period of absent SEPs and a striking latency prolongation when they returned. Postoperative recordings were absolutely normal. When the abdominal aorta was occluded, SEP alterations involved both cortical and spinal responses, so that it is difficult to distinguish between the relative roles of peripheral nerve and spinal cord ischemia. These findings indicate that SEPs can be reliably applied to spinal cord monitoring in the course of aortic surgery, even though they are mainly conducted in the posterior cord tracts.
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Aneurisma de la Aorta/cirugía , Potenciales Evocados Somatosensoriales , Médula Espinal/fisiología , Anciano , Aorta Abdominal , Aorta Torácica , Humanos , Cuidados Intraoperatorios/métodos , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Complicaciones Posoperatorias/prevención & control , Médula Espinal/irrigación sanguíneaRESUMEN
Enquiries centred on the perspective of users of psychiatric treatments and their families, has become an increasingly widespread method to improve the quality of treatments administered by health services. In this study, in particular, we examine the users' perception of the quality and variability of the effects of psychotherapies, the difficulties met, and the perceived help factors. The sample consists of 216 users of psychotherapy and 223 patients in psychiatric treatment with psychological support. They are outpatients, managed by the public health service. The questionnaires included closed ended, open-ended questions and scales that were previously tested on a sample of patients. The questionnaire for patients was anonymous and administered by researchers external to the medical staff. Irrespective of the diagnosis or of a concurrent pharmacological therapy, a high percentage of patients (75%), in both groups, feel improved. Improvement consist of the decrease of symptoms, a sense of feeling better, but also feeling grown up, more mature, having higher self-esteem and feeling more adequate in interpersonal relationships. This last type of result is significantly more frequent in the group of patients in psychotherapy. Besides these patients are faced with more difficulties and play more active a role while they are in treatment. The main difference between patients in psychotherapy and those in psychiatric management with psychological support is not indeed the identification of different perceived therapeutic factors, but rather the different evaluation of their relative importance. On the whole, the study seems to show that the effects of real psychotherapies include, beside an improvement of symptoms, the achievement of goals of personal growth and maturity, self-satisfaction and an increase in self-esteem, all in accordance with a conception of health as well-being and self-satisfaction rather than as absence of illness.
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Comparación Transcultural , Trastornos Mentales/terapia , Satisfacción del Paciente , Psicoterapia/métodos , Adaptación Psicológica , Adulto , Servicios Comunitarios de Salud Mental , Femenino , Humanos , Italia , Masculino , Trastornos Mentales/psicología , Calidad de Vida , Apoyo Social , Resultado del TratamientoRESUMEN
Afferent projections from both the reticular formation and the thalamic relay nuclei to nucleus reticularis thalami (R) were studied using the HRP technique. Injections were performed in different regions of the nucleus. Numerous labelled cells were found ipsilaterally in i) the lateral geniculate nucleus (GL) following HRP injections in dorsolateral regions of R and in ii) the ventrobasal complex (VB) following HRP injections in the ventral regions. No labelling of brain stem reticular structures was ever found. These results provide evidence for a direct projections from the VB and GL nuclei to R. The functional meaning of these data is discussed in relation with previous anatomical and neurophysiological findings. The hypothesis of a significant role of R in feedback circuits modulating sensory information seems to be supported.
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Núcleos Talámicos/anatomía & histología , Tálamo/anatomía & histología , Vías Aferentes/anatomía & histología , Animales , Gatos , Femenino , Cuerpos Geniculados/anatomía & histología , Histocitoquímica , Peroxidasa de Rábano Silvestre , MasculinoRESUMEN
Chronically recidivating enzootic ulcerations in the tongues of numerous milking cows in the Po river plain area in Italy. The animals were permanently kept indoors in cubicle houses and fed by hay containing high amounts of ripe yellow bristle grass (Setaria glauca (L.) Beauv. [= S. pumila Poiret]). The panicled parts of the culms were found to be the cause of the massive injuries.
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Enfermedades de los Bovinos/etiología , Úlceras Bucales/veterinaria , Poaceae/efectos adversos , Enfermedades de la Lengua/veterinaria , Alimentación Animal , Animales , Bovinos , Enfermedades de los Bovinos/patología , Femenino , Italia , Úlceras Bucales/etiología , Úlceras Bucales/patología , Lengua/patología , Enfermedades de la Lengua/etiología , Enfermedades de la Lengua/patologíaRESUMEN
Amyotrophic Lateral Sclerosis (ALS) is a devastating incurable disease. Stem-cell-based therapies represent a new possible strategy for ALS clinical research. The objectives of this Phase 1 clinical study were to assess the feasibility and toxicity of mesenchymal stem cell transplantation and to test the impact of a cell therapy in ALS patients. The trial was approved and monitored by the National Institute of Health and by the Ethics Committees of all participating Institutions. Autologous MSCs were isolated from bone marrow, expanded in vitro and analyzed according to GMP conditions. Expanded MSCs were suspended in the autologous cerebrospinal fluid (CSF) and directly transplanted into the spinal cord at a high thoracic level with a surgical procedure. Ten ALS patients were enrolled and regularly monitored before and after transplantation by clinical, psychological, neuroradiological and neurophysiological assessments. There was no immediate or delayed transplant-related toxicity. Clinical, laboratory, and radiographic evaluations of the patients showed no serious transplant-related adverse events. Magnetic resonance images (MRI) showed no structural changes (including tumor formation) in either the brain or the spinal cord. However the lack of post mortem material prevents any definitive conclusion about the vitality of the MSCs after transplantation. In conclusion, this study confirms that MSC transplantation into the spinal cord of ALS patients is safe and that MSCs might have a clinical use for future ALS cell based clinical trials.