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1.
Brain Struct Funct ; 229(5): 1103-1120, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38546871

RESUMEN

For at least 150,000 years, the human body has been culturally modified by the wearing of personal ornaments and probably by painting with red pigment. The present study used functional magnetic resonance imaging to explore the brain networks involved in attributing social status from face decorations. Results showed the fusiform gyrus, orbitofrontal cortex, and salience network were involved in social encoding, categorization, and evaluation. The hippocampus and parahippocampus were activated due to the memory and associative skills required for the task, while the inferior frontal gyrus likely interpreted face ornaments as symbols. Resting-state functional connectivity analysis clarified the interaction between these regions. The study highlights the importance of these neural interactions in the symbolic interpretation of social markers on the human face, which were likely active in early Homo species and intensified with Homo sapiens populations as more complex technologies were developed to culturalize the human face.


Asunto(s)
Mapeo Encefálico , Encéfalo , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Estatus Social , Cara , Reconocimiento Facial/fisiología
2.
Ann Cardiol Angeiol (Paris) ; 70(3): 161-167, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33958189

RESUMEN

PURPOSE: Spontaneous coronary artery dissection (SCAD) may occur in middle age population without any cardiovascular risk factor. We retrospectively evaluated anatomic features of 11 patients with SCAD using a coronary arteries computed tomography (CCT), compared to age and sex balanced patients who underwent CCT. MATERIAL AND METHODS: CCT was performed in 11 patients (7 females and 4 males) as follow-up in patients with SCAD (left anterior descending - LAD or circumflex artery - Cx) and compared, using the propensity score matching analysis, with 11 healthy patients. Several anatomic features were evaluated: Left main (LM) length, angle between descending coronary artery (LAD) and its first branch, angle between LAD and LM, distance from the annulus to RCA (a-RCA distance) and LM (a-LM distance) ostia and their ratio; ratio between LM length and length a-LM and tortuosity score of the vessel with SCAD. A fluid dynamic analysis has been performed to evaluate the effects on shear stress of vessels wall. RESULTS: LM length was significantly shorter in patients with SCAD versus healthy subjects (P=0.01) as well as LM length/a-LM (P=0.03) and the angle between LAD and the first adjacent branch was sharper (P<0.01). Tortuosity score showed a statistically significant difference between groups (P<0.001). Fluid dynamic analysis demonstrates that, in SCAD group, an angle<90 degree is present at the first bifurcation and it can be a cause of increased strain on vessel wall in patients with high tortuosity of coronary artery. CONCLUSION: Tortuosity and angle between the LAD and the adjacent arterial branch combined may determine increased shear stress on the vessel wall that increases the risk of SCAD.


Asunto(s)
Angiografía por Tomografía Computarizada , Angiografía Coronaria/métodos , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Puntaje de Propensión , Enfermedades Vasculares/congénito , Factores de Edad , Estudios de Casos y Controles , Anomalías de los Vasos Coronarios/etiología , Anomalías de los Vasos Coronarios/fisiopatología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/patología , Vasos Coronarios/fisiopatología , Femenino , Hemorreología/fisiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores Sexuales , Enfermedades Vasculares/diagnóstico por imagen , Enfermedades Vasculares/etiología , Enfermedades Vasculares/fisiopatología
3.
Science ; 367(6485)2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32217702

RESUMEN

Marine food-reliant subsistence systems such as those in the African Middle Stone Age (MSA) were not thought to exist in Europe until the much later Mesolithic. Whether this apparent lag reflects taphonomic biases or behavioral distinctions between archaic and modern humans remains much debated. Figueira Brava cave, in the Arrábida range (Portugal), provides an exceptionally well preserved record of Neandertal coastal resource exploitation on a comparable scale to the MSA and dated to ~86 to 106 thousand years ago. The breadth of the subsistence base-pine nuts, marine invertebrates, fish, marine birds and mammals, tortoises, waterfowl, and hoofed game-exceeds that of regional early Holocene sites. Fisher-hunter-gatherer economies are not the preserve of anatomically modern people; by the Last Interglacial, they were in place across the Old World in the appropriate settings.


Asunto(s)
Dieta , Hombre de Neandertal , Exoesqueleto , Animales , Arqueología , Océano Atlántico , Aves , Cuevas , Peces , Mamíferos , Nueces , Pinus , Portugal , Alimentos Marinos , Tortugas
4.
R Soc Open Sci ; 6(7): 190086, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31417715

RESUMEN

The earliest human graphic productions, consisting of abstract patterns engraved on a variety of media, date to the Lower and Middle Palaeolithic. They are associated with anatomically modern and archaic hominins. The nature and significance of these engravings are still under question. To address this issue, we used functional magnetic resonance imaging to compare brain activations triggered by the perception of engraved patterns dating between 540 000 and 30 000 years before the present with those elicited by the perception of scenes, objects, symbol-like characters and written words. The perception of the engravings bilaterally activated regions along the ventral route in a pattern similar to that activated by the perception of objects, suggesting that these graphic productions are processed as organized visual representations in the brain. Moreover, the perception of the engravings led to a leftward activation of the visual word form area. These results support the hypothesis that these engravings have the visual properties of meaningful representations in present-day humans, and could have served such purpose in early modern humans and archaic hominins.

6.
Phys Med Biol ; 64(8): 085015, 2019 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-30913547

RESUMEN

Fricke gel radiochemical sensors based on various matrices have been studied for decades as 3D dosimeters for radiotherapy. Despite their many appealing features, progressive aging and blurring of the signal have prevented the widespread use of these dosimeters, so far. We have addressed these shortcomings and hereby present our development of a Fricke gel based on a chemically cross-linked PVA matrix. We investigated the influence of several parameters of the polymeric matrix on sensitivity, diffusion coefficient and spontaneous oxidation of the proposed gel dosimeter. Based on these findings, we optimized the gel compositions. Our new gel formulation combines transparency, high sensitivity and simple production method, typical of gels based on natural polymers, with low diffusion coefficient and slow spontaneous oxidation typical of PVA gels made by freezing-thawing.


Asunto(s)
Geles/química , Glutaral/química , Polivinilos/química , Dosímetros de Radiación , Reactivos de Enlaces Cruzados/química , Radiometría/instrumentación , Radiometría/métodos
7.
Rev Sci Instrum ; 89(5): 053304, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29864841

RESUMEN

Superheated emulsions develop visible vapor bubbles when exposed to ionizing radiation. They consist in droplets of a metastable liquid, emulsified in an inert matrix. The formation of a bubble cavity is accompanied by sound waves. Evaporated bubbles also exhibit a lower refractive index, compared to the inert gel matrix. These two physical phenomena have been exploited to count the number of evaporated bubbles and thus measure the interacting radiation flux. Systems based on piezoelectric transducers have been traditionally used to acquire the acoustic (pressure) signals generated by bubble evaporation. Such systems can operate at ambient noise levels exceeding 100 dB; however, they are affected by a significant dead time (>10 ms). An optical readout technique relying on the scattering of light by neutron-induced bubbles has been recently improved in order to minimize measurement dead time and ambient noise sensitivity. Beams of infra-red light from light-emitting diode (LED) sources cross the active area of the detector and are deflected by evaporated bubbles. The scattered light correlates with bubble density. Planar photodiodes are affixed along the detector length in optimized positions, allowing the detection of scattered light from the bubbles and minimizing the detection of direct light from the LEDs. A low-noise signal-conditioning stage has been designed and realized to amplify the current induced in the photodiodes by scattered light and to subtract the background signal due to intrinsic scattering within the detector matrix. The proposed amplification architecture maximizes the measurement signal-to-noise ratio, yielding a readout uncertainty of 6% (±1 SD), with 1000 evaporated bubbles in a detector active volume of 150 ml (6 cm detector diameter). In this work, we prove that the intensity of scattered light also relates to the bubble size, which can be controlled by applying an external pressure to the detector emulsion. This effect can be exploited during the readout procedure to minimize shadowing effects between bubbles, which become severe when the latter are several thousands. The detector we used in this work is based on superheated C-318 (octafluorocyclobutane), emulsified in 100 µm ± 10% (1 SD) diameter drops in an inert matrix of approximately 150 ml. The detector was operated at room temperature and ambient pressure.

8.
Proc Natl Acad Sci U S A ; 115(22): 5798-5803, 2018 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-29760072

RESUMEN

Injury to the enteric nervous system (ENS) can cause several gastrointestinal (GI) disorders including achalasia, irritable bowel syndrome, and gastroparesis. Recently, a subpopulation of enteric glial cells with neuronal stem/progenitor properties (ENSCs) has been identified in the adult ENS. ENSCs have the ability of reconstituting the enteric neuronal pool after damage of the myenteric plexus. Since the estrogen receptor ß (ERß) is expressed in enteric glial cells and neurons, we investigated whether a selective ERß agonist, LY3201, can influence neuronal and glial cell differentiation. Myenteric ganglia from the murine muscularis externa were isolated and cultured in either glial cell medium or neuronal medium. In glial cell medium, the number of glial progenitor cells (Sox10+) was increased by fourfold in the presence of LY3201. In the neuronal medium supplemented with an antimitotic agent to block glial cell proliferation, LY3201 elicited a 2.7-fold increase in the number of neurons (neurofilament+ or HuC/D+). In addition, the effect of LY3201 was evaluated in vivo in two murine models of enteric neuronal damage and loss, namely, high-fat diet and topical application of the cationic detergent benzalkonium chloride (BAC) on the intestinal serosa, respectively. In both models, treatment with LY3201 significantly increased the recovery of neurons after damage. Thus, LY3201 was able to stimulate glial-to-neuron cell differentiation in vitro and promoted neurogenesis in the damaged myenteric plexus in vivo. Overall, our study suggests that selective ERß agonists may represent a therapeutic tool to treat patients suffering from GI disorders, caused by excessive neuronal/glial cell damage.


Asunto(s)
Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Receptor beta de Estrógeno/metabolismo , Plexo Mientérico/citología , Neuroglía/citología , Neuronas/citología , Animales , Dieta Alta en Grasa , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Plexo Mientérico/lesiones , Neuroglía/metabolismo , Neuronas/metabolismo , Obesidad
9.
Radiat Prot Dosimetry ; 180(1-4): 210-214, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29697813

RESUMEN

In recent years, neutron detection with superheated emulsions has received renewed attention thanks to improved detector manufacturing and read-out techniques, and thanks to successful applications in warhead verification and special nuclear material (SNM) interdiction. Detectors are currently manufactured with methods allowing high uniformity of the drop sizes, which in turn allows the use of optical read-out techniques based on dynamic light scattering. Small detector cartridges arranged in 2D matrices are developed for the verification of a declared warhead without revealing its design. For this application, the enabling features of the emulsions are that bubbles formed at different times cannot be distinguished from each other, while the passive nature of the detectors avoids the susceptibility to electronic snooping and tampering. Large modules of emulsions are developed to detect the presence of shielded special nuclear materials hidden in cargo containers 'interrogated' with high energy X-rays. In this case, the enabling features of the emulsions are photon discrimination, a neutron detection threshold close to 3 MeV and a rate-insensitive read-out.


Asunto(s)
Emulsiones , Neutrones , Armas Nucleares , Protección Radiológica/métodos , Dispersión de Radiación , Carbono/química , Clorofluorocarburos/química , Diseño de Equipo , Análisis de Falla de Equipo , Vidrio , Luz , Ensayo de Materiales , Método de Montecarlo , Reactores Nucleares , Exposición Profesional/análisis , Fotones , Radiometría , Temperatura , Rayos X
10.
Transl Psychiatry ; 5: e512, 2015 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-25689573

RESUMEN

Increasing evidence points to a role for dysfunctional glutamate N-methyl-D-aspartate receptor (NMDAR) neurotransmission in schizophrenia. D-aspartate is an atypical amino acid that activates NMDARs through binding to the glutamate site on GluN2 subunits. D-aspartate is present in high amounts in the embryonic brain of mammals and rapidly decreases after birth, due to the activity of the enzyme D-aspartate oxidase (DDO). The agonistic activity exerted by D-aspartate on NMDARs and its neurodevelopmental occurrence make this D-amino acid a potential mediator for some of the NMDAR-related alterations observed in schizophrenia. Consistently, substantial reductions of D-aspartate and NMDA were recently observed in the postmortem prefrontal cortex of schizophrenic patients. Here we show that DDO mRNA expression is increased in prefrontal samples of schizophrenic patients, thus suggesting a plausible molecular event responsible for the D-aspartate imbalance previously described. To investigate whether altered D-aspartate levels can modulate schizophrenia-relevant circuits and behaviors, we also measured the psychotomimetic effects produced by the NMDAR antagonist, phencyclidine, in Ddo knockout mice (Ddo(-)(/-)), an animal model characterized by tonically increased D-aspartate levels since perinatal life. We show that Ddo(-/-) mice display a significant reduction in motor hyperactivity and prepulse inhibition deficit induced by phencyclidine, compared with controls. Furthermore, we reveal that increased levels of D-aspartate in Ddo(-/-) animals can significantly inhibit functional circuits activated by phencyclidine, and affect the development of cortico-hippocampal connectivity networks potentially involved in schizophrenia. Collectively, the present results suggest that altered D-aspartate levels can influence neurodevelopmental brain processes relevant to schizophrenia.


Asunto(s)
Conducta Animal/efectos de los fármacos , D-Aspartato Oxidasa/genética , Antagonistas de Aminoácidos Excitadores/farmacología , Fenciclidina/farmacología , Corteza Prefrontal/metabolismo , Adulto , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatología , Estudios de Casos y Controles , D-Aspartato Oxidasa/metabolismo , Metilación de ADN , Modelos Animales de Enfermedad , Femenino , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Actividad Motora/efectos de los fármacos , Actividad Motora/genética , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/fisiopatología , Inhibición Prepulso/efectos de los fármacos , Inhibición Prepulso/genética , Esquizofrenia
11.
Transl Psychiatry ; 4: e427, 2014 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-25136890

RESUMEN

Autism spectrum disorders (ASD) are neurodevelopmental conditions characterized by pronounced social and communication deficits and stereotyped behaviours. Recent psychosocial and neuroimaging studies have highlighted reward-processing deficits and reduced dopamine (DA) mesolimbic circuit reactivity in ASD patients. However, the neurobiological and molecular determinants of these deficits remain undetermined. Mouse models recapitulating ASD-like phenotypes could help generate hypotheses about the origin and neurophysiological underpinnings of clinically relevant traits. Here we used functional magnetic resonance imaging (fMRI), behavioural and molecular readouts to probe dopamine neurotransmission responsivity in BTBR T(+) Itpr3(tf)/J mice (BTBR), an inbred mouse line widely used to model ASD-like symptoms owing to its robust social and communication deficits, and high level of repetitive stereotyped behaviours. C57BL/6J (B6) mice were used as normosocial reference comparators. DA reuptake inhibition with GBR 12909 produced significant striatal DA release in both strains, but failed to elicit fMRI activation in widespread forebrain areas of BTBR mice, including mesolimbic reward and striatal terminals. In addition, BTBR mice exhibited no appreciable motor responses to GBR 12909. DA D1 receptor-dependent behavioural and signalling responses were found to be unaltered in BTBR mice, whereas dramatic reductions in pre- and postsynaptic DA D2 and adenosine A2A receptor function was observed in these animals. Overall these results document profoundly compromised DA D2-mediated neurotransmission in BTBR mice, a finding that is likely to have a role in the distinctive social and behavioural deficits exhibited by these mice. Our results call for a deeper investigation of the role of dopaminergic dysfunction in mouse lines exhibiting ASD-like phenotypes, and possibly in ASD patient populations.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/fisiopatología , Modelos Animales de Enfermedad , Dopamina/fisiología , Transmisión Sináptica/fisiología , Animales , Nivel de Alerta/fisiología , Conducta Animal/fisiología , Trastornos Generalizados del Desarrollo Infantil/diagnóstico , Trastornos Generalizados del Desarrollo Infantil/psicología , Sistema Límbico/fisiopatología , Imagen por Resonancia Magnética , Mesencéfalo/fisiopatología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Red Nerviosa/fisiopatología , Receptores de Dopamina D2/fisiología , Valores de Referencia , Conducta Social , Conducta Estereotipada
12.
Transl Psychiatry ; 4: e417, 2014 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-25072322

RESUMEN

D-aspartate (D-Asp) is an atypical amino acid, which is especially abundant in the developing mammalian brain, and can bind to and activate N-methyl-D-Aspartate receptors (NMDARs). In line with its pharmacological features, we find that mice chronically treated with D-Asp show enhanced NMDAR-mediated miniature excitatory postsynaptic currents and basal cerebral blood volume in fronto-hippocampal areas. In addition, we show that both chronic administration of D-Asp and deletion of the gene coding for the catabolic enzyme D-aspartate oxidase (DDO) trigger plastic modifications of neuronal cytoarchitecture in the prefrontal cortex and CA1 subfield of the hippocampus and promote a cytochalasin D-sensitive form of synaptic plasticity in adult mouse brains. To translate these findings in humans and consistent with the experiments using Ddo gene targeting in animals, we performed a hierarchical stepwise translational genetic approach. Specifically, we investigated the association of variation in the gene coding for DDO with complex human prefrontal phenotypes. We demonstrate that genetic variation predicting reduced expression of DDO in postmortem human prefrontal cortex is mapped on greater prefrontal gray matter and activity during working memory as measured with MRI. In conclusion our results identify novel NMDAR-dependent effects of D-Asp on plasticity and physiology in rodents, which also map to prefrontal phenotypes in humans.


Asunto(s)
Encéfalo/fisiología , Ácido D-Aspártico/fisiología , Sustancia Gris/fisiología , Plasticidad Neuronal/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Adulto , Animales , Encéfalo/patología , D-Aspartato Oxidasa/genética , D-Aspartato Oxidasa/fisiología , Femenino , Eliminación de Gen , Regulación Enzimológica de la Expresión Génica/genética , Sustancia Gris/patología , Hipocampo/patología , Hipocampo/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria a Corto Plazo/fisiología , Ratones , Ratones Endogámicos C57BL , Plasticidad Neuronal/genética , Tamaño de los Órganos/genética , Tamaño de los Órganos/fisiología , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Corteza Prefrontal/patología , Corteza Prefrontal/fisiología , Biosíntesis de Proteínas/genética , ARN Mensajero/genética
13.
Appl Radiat Isot ; 88: 216-20, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24461556

RESUMEN

Experimental activities are underway at INFN Legnaro National Laboratories (LNL) (Padua, Italy) and Pisa University aimed at angular-dependent neutron energy spectra measurements produced by the (9)Be(p,xn) reaction, under a 5MeV proton beam. This work has been performed in the framework of INFN TRASCO-BNCT project. Bonner Sphere Spectrometer (BSS), based on (6)LiI (Eu) scintillator, was used with the shadow-cone technique. Proper unfolding codes, coupled to BSS response function calculated by Monte Carlo code, were finally used. The main results are reported here.


Asunto(s)
Terapia por Captura de Neutrón de Boro/instrumentación , Neutrones/uso terapéutico , Aceleradores de Partículas/instrumentación , Radiometría/instrumentación , Análisis Espectral/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Dosificación Radioterapéutica
14.
Radiat Prot Dosimetry ; 158(2): 216-20, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23960242

RESUMEN

Anthropomorphic tissue-equivalent hand phantoms were achieved to measure the extremity dose involved in Zevalin (90)Y-labelling and patient delivering procedure for radioimmunotherapy treatment of non-Hodgkin lymphoma. The extremity doses to hands and wrists of operators were measured by using thermoluminescent detectors mounted on the developed phantoms. Measurements of chest- and lens-equivalent doses performed on a Rando phantom are also reported.


Asunto(s)
Anticuerpos Monoclonales/análisis , Mano/efectos de la radiación , Linfoma no Hodgkin/radioterapia , Fantasmas de Imagen , Radioinmunoterapia/métodos , Radiometría/métodos , Radioisótopos de Itrio/análisis , Antropometría , Calibración , Humanos , Dosis de Radiación , Protección Radiológica , Dosimetría Termoluminiscente/métodos , Distribución Tisular
15.
J Biol Regul Homeost Agents ; 27(2 Suppl): 49-59, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24813315

RESUMEN

Nowadays it is widely recognized that D-amino acids are present in bacteria as well as in eukaryotes, including mammals. In particular, free D-serine and D-aspartate are found in the brain of mammals. Notably, D-aspartate occurs at substantial levels in the embryo brain to then consistently decrease at post-natal phases. Temporal regulation of D-aspartate content depends on the post-natal onset of D-aspartate oxidase expression, the only known enzyme able to catabolize this D-amino acid. Pharmacological evidence indicates that D-aspartate binds and activates NMDA receptors (NMDARs). To decipher the physiological function of D-aspartate in mammals, in the last years, genetic and pharmacological mouse models with abnormally higher levels of this D-amino acid have been generated. Overall, these animal models have pointed out a significant neuromodulatory role for D-aspartate in the regulation of NMDAR-dependent functions. Indeed, increased content of D-aspartate are able to increase hippocampal NMDAR-dependent long-term potentiation (LTP) and spatial memory of adult mice. However, if exposure to elevated levels of D-Asp lasts for the entire lifetime of mice, enhancement of synaptic plasticity turns into a dramatic worsening, thus triggering an acceleration of the NMDAR-dependent aging processes in the hippocampus. Nonetheless, administration of D-Asp to old mice can restore the physiological age-related decay of hippocampal NMDA-related LTP. Besides its effect on hippocampus-dependent processes in mouse models, different points of evidence are indicating, today, a potential role for D-Asp in neurologic and psychiatric disorders associated with aberrant signalling of NMDARs.

16.
Br J Pharmacol ; 168(2): 502-17, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22924679

RESUMEN

BACKGROUND AND PURPOSE: Glutamate transmission is dysregulated in both multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE), the animal model of MS. A characteristic of EAE is increased glutamate transmission associated with up-regulation of AMPA receptors. However, little is known about the role of NMDA receptors in the synaptic modifications induced by EAE. EXPERIMENTAL APPROACH: The contribution of NMDA receptors to the alterations of glutamate transmission and disease severity in EAE mice was assessed by means of neurophysiological, morphological, Western blot, metabolic and clinical score assessments. KEY RESULTS: In our EAE mice, there was an NMDA receptor-dependent increase of glutamate release, associated with marked activation of the astroglia. Presynaptic NMDA receptors became overactive during EAE, increasing synaptic glutamate release by a mechanism dependent on voltage-gated sodium channels. By means of NAD(P)H autofluorescence analysis, we also found that EAE has a glutamate and NMDA receptor-dependent dysfunction of mitochondrial activity, which is known to contribute to the neurodegenerative damage of MS and EAE. Furthermore, pharmacological blockade of NMDA receptors in vivo ameliorated both synaptic transmission defects and of the clinical disease course of EAE mice, while EAE induced in mice with a genetically enhanced NMDA receptor signalling had opposite effects. CONCLUSIONS AND IMPLICATIONS: Our data, showing both sensitization of NMDA receptors and their involvement in the progression of the EAE disease, supggest that pharmacological impairment of NMDA receptor signalling would be a component of a neuroprotection strategy in MS.


Asunto(s)
Encefalomielitis Autoinmune Experimental/fisiopatología , Ácido Glutámico/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Animales , Maleato de Dizocilpina/farmacología , Encefalomielitis Autoinmune Experimental/metabolismo , Antagonistas de Aminoácidos Excitadores/farmacología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Sinapsis/fisiología , Canales de Sodio Activados por Voltaje/fisiología
17.
Int J Immunopathol Pharmacol ; 25(1): 275-80, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22507341

RESUMEN

We describe the case of a 45-year-old woman who had drawn our attention for some recent episodes of transient global amnesia that, upon further examination, resulted from ischemic events caused by multiple arterial thrombosis (bilateral internal carotid occlusion, significant stenosis of the right external carotid, mild stenosis of the right vertebral artery, right anterior cerebral artery occlusion and severe stenosis of the anterior descending coronary artery) due to primary antiphospholipid syndrome. Revascularisation of either carotid was not attempted. A percutaneous intervention in the anterior descending coronary artery stenosis was performed successfully. Due to severe arterial thrombosis, the patient was discharged with only duplex antiplatelet treatment and subcutaneous anticoagulant therapy, since immunotherapy is not indicated in primary APS. The occurrence of transient global amnesia should raise the suspicion of APS.


Asunto(s)
Amnesia Global Transitoria/etiología , Síndrome Antifosfolípido/complicaciones , Femenino , Humanos , Persona de Mediana Edad
18.
J Hum Evol ; 60(2): 145-57, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21131024

RESUMEN

We report on the analysis of three human cranial fragments from a Mousterian context at the site of La Quina (France), which show anthropogenic surface modifications. Macroscopic and microscopic analyses, including SEM observation, demonstrate that the modifications visible on one of these fragments are similar to those produced on bone fragments used experimentally to retouch flakes. The microscopic analysis also identified ancient scraping marks, possibly resulting from the cleaning of the skull prior to its breakage and utilisation of a resulting fragment as a tool. The traces of utilisation and the dimensions of this object are compared to those on a sample of 67 bone retouchers found in the same excavation area and layer. Results show that the tool size, as well as the dimensions and location of the utilised area, fall well within the range of variation observed on faunal shaft fragments from La Quina that were used as retouchers. This skull fragment represents the earliest known use of human bone as a raw material and the first reported use of human bone for this purpose by hominins other than modern humans. The two other skull fragments, which probably come from the same individual, also bear anthropogenic surface modifications in the form of percussion, cut, and scraping marks. The deliberate versus unintentional hypotheses for the unusual choice of the bone are presented in light of contextual information, modifications identified on the two skull fragments not used as tools, and data on bone retouchers from the same layer, the same site, and other Mousterian sites.


Asunto(s)
Huesos , Hominidae , Animales , Arqueología , Huesos/anatomía & histología , Fósiles , Francia , Humanos , Comportamiento del Uso de la Herramienta
19.
J Cell Physiol ; 224(1): 234-41, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20333645

RESUMEN

The CD133 molecule has been proposed as a surface marker of cancer stem cells in several human malignancies, including colon cancers. The function and the mechanisms regulating CD133 expression remain unknown. The HT29 human colon cancer cells undergo differentiation following treatment with various agents and represent a useful in vitro model of colon differentiation. This study evaluated the behavior of CD133 during sodium butyrate-induced differentiation of HT29 cells. Treatment with sodium butyrate induced a progressive decrease of CD133 expression, as assessed by flow cytometry using the AC133 monoclonal antibody. Indeed, expression of CD133, which was about 47% in untreated control cells, gradually decreased down to about 3% after 72 h in a time- and dose-dependent manner. No relationship was observed between CD133 protein evaluated by flow cytometry and mRNA expression level, and no changes were detected in the methylation status of the CD133 gene promoter during HT29 differentiation. Moreover, the expression of the CD133 protein, evaluated by Western blot analysis using a specific anti-CD133 antibody directed against the C-terminal intracytoplasmic region of human CD133 protein, did not correlate with flow cytometry results. Different results were also obtained using the two antibodies to analyze the expression of the CD133 molecule in human colon cancers. These findings demonstrate that membrane expression of the CD133 stem cell marker might undergo a complex regulation during differentiation of colon cells and suggest that HT29 cells are a useful in vitro model to study the mechanisms involved in this regulation which likely occurs at a post-transcriptional level.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Butiratos/farmacología , Diferenciación Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Neoplasias del Colon/inmunología , Glicoproteínas/metabolismo , Péptidos/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Antígeno AC133 , Antígenos CD/genética , Antígenos de Neoplasias/genética , Secuencia de Bases , Membrana Celular/inmunología , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Metilación de ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glicoproteínas/genética , Glicosilación , Células HT29 , Humanos , Datos de Secuencia Molecular , Péptidos/genética , Estructura Terciaria de Proteína , ARN Mensajero/metabolismo , Factores de Tiempo
20.
Appl Radiat Isot ; 67(7-8 Suppl): S141-4, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19376712

RESUMEN

An accelerator-driven thermal neutron facility for boron neutron capture therapy of skin melanoma is currently under construction at the Legnaro National Laboratories, Italy. The installation relies on the production of neutrons from a thick beryllium target bombarded with 5 MeV protons. A complete set of double differential data, i.e. angle- and energy-differential neutron spectra produced by the beryllium target, is necessary for the Monte Carlo-based design of the installation. For this purpose, double differential fluence measurements are currently performed with the "BINS" neutron spectrometer using 5 MeV protons at the "CN" Van de Graaf accelerator. This spectrometer uses a superheated emulsion of dichlorotetrafluoroethane which is sequentially operated at 25, 30, 35, 40, 45, 50 and 55 degrees C and thus provides a series of seven sharp thresholds covering the 0.1-10 MeV neutron energy interval. Deconvolution of the data is performed with the code "MAXED", which is based on the maximum entropy principle. The analysis of our first neutron spectrometry measurements at angles of 0 degrees, 40 degrees, 80 degrees and 120 degrees supports the viability of the BINS spectrometry method for the generation of the required double differential data.


Asunto(s)
Terapia por Captura de Neutrón de Boro/instrumentación , Terapia por Captura de Neutrón de Boro/estadística & datos numéricos , Neutrones Rápidos/uso terapéutico , Humanos , Italia , Melanoma/radioterapia , Método de Montecarlo , Reactores Nucleares , Neoplasias Cutáneas/radioterapia , Análisis Espectral
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