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1.
Sci Rep ; 8(1): 12634, 2018 Aug 22.
Article in English | MEDLINE | ID: mdl-30135459

ABSTRACT

A universal relation is established between the quantum work probability distribution of an isolated driven quantum system and the Loschmidt echo dynamics of a two-mode squeezed state. When the initial density matrix is canonical, the Loschmidt echo of the purified double thermofield state provides a direct measure of information scrambling and can be related to the analytic continuation of the partition function. Information scrambling is then described by the quantum work statistics associated with the time-reversal operation on a single copy, associated with the sudden negation of the system Hamiltonian.

2.
Actas dermo-sifiliogr. (Ed. impr.) ; 106(5): 106.e23-106.e26, jun. 2015. tab
Article in Spanish | IBECS | ID: ibc-139848

ABSTRACT

Ante los casos de pacientes con historia de dermatitis facial y con dermatitis de contacto por hipersensibilidad al níquel se propuso investigar fuentes alternativas de exposición, por ejemplo monedas, que fuesen transferidas por los dedos hasta la región facial. Se utilizó cinta adhesiva común para realizar un stripping sobre los dedos y los pómulos de los voluntarios, y se llevó a cabo un análisis a través de técnicas de espectrometría atómica. Los resultados de níquel obtenidos fueron positivos tanto en los dedos, 14,67 ppm a 58,64 ppm, como en los pómulos, desde 1,28 ppm a 8,52 ppm, con niveles en controles muy inferiores y significativamente distintos a dichos valores. La transferencia de níquel desde el objeto que lo contiene hasta la cara del individuo mediante sus dedos podría justificar la clínica presentada por estos pacientes (AU)


We investigated fingers as a potential source of nickel transfer to the face in patients with allergic contact dermatitis to nickel and a history of facial dermatitis. Samples were collected from the fingers and cheeks of volunteers using the stripping method with standard adhesive tape, and nickel levels were quantified using mass spectrometry. Fingers and cheeks of individuals who had handled coins were both positive for nickel, with levels ranging from 14.67 to 58.64 ppm and 1.28 to 8.52 ppm, respectively. The levels in a control group were considerably and significantly lower. Transfer of nickel from a person’s fingers to their face after handling a nickel-containing object could explain the presence of facial dermatitis in patients with nickel hypersensitivity (AU)


Subject(s)
Female , Humans , Adult , Middle Aged , Nickel/adverse effects , Dermatitis, Allergic Contact/etiology , Facial Dermatoses/chemically induced , Numismatics , Cheek , Fingers , Occupational Exposure , Patch Tests , Surgical Tape
3.
Actas Dermosifiliogr ; 106(5): e23-6, 2015 Jun.
Article in English, Spanish | MEDLINE | ID: mdl-25770847

ABSTRACT

We investigated fingers as a potential source of nickel transfer to the face in patients with allergic contact dermatitis to nickel and a history of facial dermatitis. Samples were collected from the fingers and cheeks of volunteers using the stripping method with standard adhesive tape, and nickel levels were quantified using mass spectrometry. Fingers and cheeks of individuals who had handled coins were both positive for nickel, with levels ranging from 14.67 to 58.64 ppm and 1.28 to 8.52 ppm, respectively. The levels in a control group were considerably and significantly lower. Transfer of nickel from a person's fingers to their face after handling a nickel-containing object could explain the presence of facial dermatitis in patients with nickel hypersensitivity.


Subject(s)
Dermatitis, Allergic Contact/etiology , Facial Dermatoses/chemically induced , Nickel/adverse effects , Numismatics , Adult , Cheek , Female , Fingers , Humans , Middle Aged , Occupational Exposure , Patch Tests , Surgical Tape
4.
Sci Total Environ ; 511: 723-37, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-25618818

ABSTRACT

New particle formation (NPF) was investigated at a coastal background site in Southwest Spain over a four-year period using a Scanning Particle Mobility Sizer (SMPS). The goals of the study were to characterise the NPF and to investigate their relationship to meteorology, gas phase (O3, SO2, CO and NO2) and solar radiation (UVA, UVB and global). A methodology for identifying and classifying the NPF was implemented using the wind direction and modal concentrations as inputs. NPF events showed a frequency of 24% of the total days analysed. The mean duration was 9.2±4.2 h. Contrary to previous studies conducted in other locations, the NPF frequency reached its maximum during cold seasons for approximately 30% of the days. The lowest frequency took place in July with 10%, and the seasonal wind pattern was found to be the most important parameter influencing the NPF frequency. The mean formation rate was 2.2±1.7 cm(-3) s(-1), with a maximum in the spring and early autumn and a minimum during the summer and winter. The mean growth rate was 3.8±2.4 nm h(-1) with higher values occurring from spring to autumn. The mean and seasonal formation and growth rates are in agreement with previous observations from continental sites in the Northern Hemisphere. NPF classification of different classes was conducted to explore the effect of synoptic and regional-scale patterns on NPF and growth. The results show that under a breeze regime, the temperature indirectly affects NPF events. Higher temperatures increase the strength of the breeze recirculation, favouring gas accumulation and subsequent NPF appearance. Additionally, the role of high relative humidity in inhibiting the NPF was evinced during synoptic scenarios. The remaining meteorological variables (RH), trace gases (CO and NO), solar radiation, PM10 and condensation sink, showed a moderate or high connection with both formation and growth rates.

5.
J Physiol Pharmacol ; 65(2): 229-39, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24781732

ABSTRACT

The autophagic process is a lysosomal degradation pathway, which is activated during stress conditions, such as starvation or exercise. Regular exercise has beneficial effects on human health, including neuroprotection. However, the cellular mechanisms underlying these effects are incompletely understood. Endurance and a single bout of exercise induce autophagy not only in brain but also in peripheral tissues. However, little is known whether autophagy could be modulated in brain and peripheral tissues by long-term moderate exercise. Here, we examined the effects on macroautophagy process of long-term moderate treadmill training (36 weeks) in adult rats both in brain (hippocampus and cerebral cortex) and peripheral tissues (skeletal muscle, liver and heart). We assessed mTOR activation and the autophagic proteins Beclin 1, p62, LC3B (LC3B-II/LC3B-I ratio) and the lysosomal protein LAMP1, as well as the ubiquitinated proteins. Our results showed in the cortex of exercised rats an inactivation of mTOR, greater autophagy flux (increased LC3-II/LC3-I ratio and reduced p62) besides increased LAMP1. Related with these effects a reduction in the ubiquitinated proteins was observed. No significant changes in the autophagic pathway were found either in hippocampus or in skeletal and cardiac muscle by exercise. Only in the liver of exercised rats mTOR phosphorylation and p62 levels increased, which could be related with beneficial metabolic effects in this organ induced by exercise. Thus, our findings suggest that long-term moderate exercise induces autophagy specifically in the cortex.


Subject(s)
Autophagy/physiology , Cerebral Cortex/metabolism , Liver/metabolism , Physical Conditioning, Animal/physiology , Animals , Apoptosis Regulatory Proteins/metabolism , Beclin-1 , Heat-Shock Proteins/metabolism , Hippocampus/metabolism , Lysosomal Membrane Proteins/metabolism , Male , Microtubule-Associated Proteins/metabolism , Muscle, Skeletal/metabolism , Myocardium/metabolism , Rats, Sprague-Dawley , Sequestosome-1 Protein , TOR Serine-Threonine Kinases/metabolism
8.
Neuropathol Appl Neurobiol ; 37(5): 525-37, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21175737

ABSTRACT

AIMS: 3-Nitropropionic acid (3-NPA) is a natural toxin that, when administered to experimental animals, reproduces the brain lesions observed in Huntington's disease, which mainly consist of selective neurodegeneration of the striatum. The lesions also include severe alterations to the blood-brain barrier (BBB), which increase its permeability to several substances including blood components and exogenous fluorescent dyes, and the concomitant degradation of some of its constituents such as endothelial cells, tight junction proteins and the basement membrane. We studied here the role of matrix metalloproteinases (MMPs)-2 and -9, also called gelatinases A and B, in the degradation of the BBB in the striatal lesions induced by the systemic administration of 3-NPA to Sprague-Dawley rats. METHODS: 3-NPA was intraperitoneally administered at a dose of 20 mg/kg once a day for 3 days. MMPs were studied by means of immunohistochemistry and in situ zymography. RESULTS: In 3-NPA-treated rats, MMP-9 was present in most of the degraded blood vessels in the injured striatum, while it was absent in vessels from non-injured tissue. In the same animals, MMP-2 staining was barely detected close to degraded blood vessels. The combination of MMP-9 immunostaining, in situ zymography and inhibitory studies of MMP-9 confirmed that net gelatinolytic activity detected in the degraded striatal blood vessels could be attributed almost exclusively to the active form of MMP-9. CONCLUSION: Our results highlight the prominent role of MMP-9 in BBB disruption in the striatal injured areas of this experimental model of Huntington's disease.


Subject(s)
Blood-Brain Barrier/enzymology , Corpus Striatum/enzymology , Huntington Disease/enzymology , Huntington Disease/pathology , Matrix Metalloproteinase 9/metabolism , Animals , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/pathology , Corpus Striatum/drug effects , Corpus Striatum/pathology , Disease Models, Animal , Huntington Disease/chemically induced , Immunohistochemistry , Male , Neurotoxins/toxicity , Nitro Compounds/toxicity , Propionates/toxicity , Rats , Rats, Sprague-Dawley
10.
Biol Cybern ; 100(4): 271-87, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19229555

ABSTRACT

In this paper, we present a neural network model of the interactions between cortex and the basal ganglia during prehensile movements. Computational neuroscience methods are used to explore the hypothesis that the altered kinematic patterns observed in Parkinson's disease patients performing prehensile movements is mainly due to an altered neuronal activity located in the networks of cholinergic (ACh) interneurons of the striatum. These striatal cells, under a strong influence of the dopaminergic system, significantly contribute to the neural processing within the striatum and in the cortico-basal ganglia loops. In order to test this hypothesis, a large-scale model of neural interactions in the basal ganglia has been integrated with previous models accounting for the cortical organization of goal directed reaching and grasping movements in normal and perturbed conditions. We carry out a discussion of the model hypothesis validation by providing a control engineering analysis and by comparing results of real experiments with our simulation results in conditions resembling these original experiments.


Subject(s)
Basal Ganglia/physiology , Models, Neurological , Movement/physiology , Neural Networks, Computer , Parkinson Disease/physiopathology , Humans , Models, Theoretical
13.
Actas Dermosifiliogr ; 98(5): 345-6, 2007 Jun.
Article in Spanish | MEDLINE | ID: mdl-17555677

ABSTRACT

We report a case of allergic contact dermatitis due to alcamphor present in a flushing solution used by a 58-year-old woman. It is the first case described in our Division of Allergy and the second one reported in the literature. Alcamphor is a chemical substance present in many products that may have been underestimated as the causative agent of contact allergic dermatitis as the allergen is not available in the standard patch test batteries.


Subject(s)
Camphor/adverse effects , Dermatitis, Allergic Contact/etiology , Female , Humans , Middle Aged
14.
Actas dermo-sifiliogr. (Ed. impr.) ; 98(5): 345-346, jun. 2007. tab
Article in Es | IBECS | ID: ibc-055570

ABSTRACT

Describimos una dermatitis de contacto alérgica por alcanfor, contenido en un líquido rubefaciente usado por una mujer de 58 años. Es el primer caso descrito en nuestra Unidad de Alergia y el segundo en la literatura. El alcanfor es una sustancia química contenida en numerosos productos y puede que se haya infravalorado como causa etiológica de dermatitis de contacto alérgicas, al no disponer del alérgeno en las baterías preparadas para la detección de dichas dermatitis


We report a case of allergic contact dermatitis due to alcamphor present in a flushing solution used by a 58-year-old woman. It is the first case described in our Division of Allergy and the second one reported in the literature. Alcamphor is a chemical substance present in many products that may have been underestimated as the causative agent of contact allergic dermatitis as the allergen is not available in the standard patch test batteries


Subject(s)
Female , Middle Aged , Humans , Camphor/adverse effects , Dermatitis, Allergic Contact/diagnosis , Irritants/adverse effects , Menthol , Turpentine
15.
Neural Netw ; 20(5): 631-45, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17442538

ABSTRACT

This paper proposes a neural network architecture for learning of grasping tasks. The multineural network model presented in this work, allows acquisition of different neural representations of the grasping task through a successive learning over two stages in a strategy that uses already learned representations for the acquisition of the subsequent knowledge. Systematic computer simulations have been carried out in order to test learning and generalization capabilities of the system. The neural activity at different subparts of the artificial neural network during its performance phase, is compared to the activity of populations of real neurons in areas AIP and F5 of the distributed parieto-frontal biological neural network involved in visual guidance of grasping. A more biologically plausible development of the model presented here is also discussed. The proposed model can be also used as a high level controller for a robotic dextrous hand during learning and execution of grasping tasks.


Subject(s)
Hand Strength/physiology , Learning/physiology , Neural Networks, Computer , Computer Simulation , Humans , Models, Neurological , Posture , Psychomotor Performance/physiology , Visual Perception/physiology
16.
Rev. esp. anestesiol. reanim ; 53(9): 545-549, nov. 2006. tab
Article in Es | IBECS | ID: ibc-050980

ABSTRACT

OBJETIVOS: Determinar si la adicción de ketamina apropofol mejora la sedación durante un bloqueo retrobulbarpara cirugía oftalmológica respecto a la administraciónde propofol solo.MATERIAL Y MÉTODOS: Estudio aleatorio a doble ciegoprospectivo sobre 50 pacientes intervenidos de cirugíaocular con anestesia retrobulbar. Asignación aleatoria endos grupos: Grupo propofol: Inducción de sedación conpropofol 0,45 mg Kg-1. Grupo propofol ketamina: Inducciónde sedación con propofol 0,45 mg Kg-1 + ketamina0,25 mg Kg-1. Se recogieron las siguientes variables:Demográficas (edad, peso, ASA, talla, sexo), hemodinámicas(TA, FC), dolor a la punción (EVA), condicionesde punción, sedación (OAA/S), ventilación (ETCO2,apneas, necesidad de maniobras de reanimación, pulsioximetría),el tiempo de inicio de acción, duración delefecto y amnesia.RESULTADOS: No hallamos diferencias significativas enel tiempo de inicio, duración del efecto, variables demográficas,hemodinámicas, respiratorias ni de amnesia.La sedación medida por la escala OAAS fue menor en elgrupo propofol y las condiciones de punción fueron significativamentemejores en el grupo propofol / ketamina.No observamos reacciones psicomiméticas adversas,excepto en 2 pacientes del grupo propofol que presentaronagitación transitoria.CONCLUSIONES: Bajas dosis de ketamina asociadas apropofol mejoran las condiciones de la punción del bloqueoretrobulbar sin aumentar los efectos indeseables


OBJECTIVES: To determine if adding ketamine topropofol provides better sedation than propofol alonefor patients receiving a retrobulbar block for eye surgery.MATERIAL AND METHODS: Randomized double-blindtrial enrolling 50 patients receiving a retrobulbar nerveblock for eye surgery. Patients were randomly assignedto 2 groups. In the propofol group sedation was inducedwith 0.45 mg·kg-1 of propofol. In the ketamine plus propofolgroup sedation was induced with 0.45 mg·kg-1 ofpropofol plus 0.25 mg·kg-1 of ketamine. We recordedpatient characteristics (age, weight, ASA class, height,sex), hemodynamic variables (blood pressure, heartrate), puncture conditions, sedation (score on theObserver's Assessment of Alertness/Sedation [OAA/S]scale), ventilation (end-tidal carbon dioxide pressure,apneas, need for reanimation maneuvers, pulse oximetry),time until onset of effect, duration of effect, andamnesia.RESULTS: No significant differences were observed intime to onset, duration of effect, patient characteristics,hemodynamic or respiratory variables, or amnesia.Sedation assessed on the OAA/S scale was lower inthe propofol group and the puncture conditions weresignificantly better in the ketamine plus propofolgroup. The only adverse psychomimetic reaction wastransient agitation, observed in 2 propofol grouppatients.CONCLUSIONS: Low doses of ketamine associated withpropofol improve puncture conditions for performing aretrobulbar block without increasing unwanted sideeffects


Subject(s)
Male , Female , Humans , Ketamine/administration & dosage , Propofol/administration & dosage , Nerve Block , Intraocular Pressure , Analgesics/administration & dosage , Double-Blind Method , Prospective Studies , Treatment Outcome , Eye , Ambulatory Surgical Procedures
17.
Rev Esp Anestesiol Reanim ; 53(7): 437-41, 2006.
Article in Spanish | MEDLINE | ID: mdl-17066863

ABSTRACT

A 6-year-old boy with Duchenne muscular dystrophy (DMD) and foreseen difficult tracheal intubation underwent tonsillectomy under general inhaled anesthesia with sevoflurane. No neuromuscular blockers were administered and no perioperative complications emerged. In spite of advances in genetic diagnosis there continue to be patients with DMD because of spontaneous mutation of the dystrophin gene. Late detection leaves them vulnerable to administration of drugs like succinylcholine that can trigger fatal reactions involving hyperpotassemia, rhabdomyolysis, and malignant hyperthermia. Total intravenous anesthesia seems the best way to provide general anesthesia for a patient with DMD. Inhaled anesthesia is an alternative. Although halogenated agents can lead to rhabdomyolysis and malignant hyperthermia, the frequency seems low if we bear in mind that the use of sevoflurane is widespread in pediatrics. In this case sevoflurane induction facilitated safe tracheal intubation.


Subject(s)
Anesthesia/methods , Anesthetics, Inhalation , Methyl Ethers , Muscular Dystrophy, Duchenne , Tonsillectomy , Child , Humans , Male , Risk Factors , Sevoflurane
19.
Rev. esp. anestesiol. reanim ; 53(7): 437-441, ago.-sept. 2006.
Article in Es | IBECS | ID: ibc-050173

ABSTRACT

Un niño de 6 años de edad, diagnosticado de distrofiamuscular de Duchenne (DMD), y con posible intubacióntraqueal difícil, fue intervenido de amigdalectomía bajoanestesia general inhalatoria con sevoflurano sin administrarbloqueantes neuromusculares, y sin objetivarsecomplicaciones perioperatorias.A pesar de los avances en diagnóstico genético,seguimos encontrando tanto portadores como afectadospor la DMD, debido a mutaciones espontáneas del gende la distrofina. Su detección tardía les hace susceptiblesa la administración de fármacos que puedendesencadenar reacciones mortales en su organismo,como la succinilcolina, que puede producir hiperpotasemia,rabdomiolisis e hipertermia maligna. Para realizaruna anestesia general a un paciente con DMD, laanestesia total endovenosa parece ser la más indicada.Una segunda opción puede ser la anestesia inhalatoria;aunque los agentes halogenados pueden desencadenarrabdomiolisis e hipertermia maligna, si se tiene encuenta el uso tan difundido de sevoflurano en pediatría,parece ser que el riesgo es excepcional. En este caso lainducción con sevoflurano facilitó realizar la intubacióntraqueal de forma segura


A 6-year-old boy with Duchenne muscular dystrophy(DMD) and foreseen difficult tracheal intubation underwenttonsillectomy under general inhaled anesthesiawith sevoflurane. No neuromuscular blockers were administeredand no perioperative complications emerged.In spite of advances in genetic diagnosis there continueto be patients with DMD because of spontaneousmutation of the dystrophin gene. Late detection leavesthem vulnerable to administration of drugs like succinylcholinethat can trigger fatal reactions involvinghyperpotassemia, rhabdomyolysis, and malignanthyperthermia. Total intravenous anesthesia seems thebest way to provide general anesthesia for a patient withDMD. Inhaled anesthesia is an alternative. Althoughhalogenated agents can lead to rhabdomyolysis andmalignant hyperthermia, the frequency seems low if webear in mind that the use of sevoflurane is widespread inpediatrics. In this case sevoflurane induction facilitatedsafe tracheal intubation


Subject(s)
Male , Child , Humans , Muscular Dystrophy, Duchenne , Anesthetics, Inhalation/therapeutic use , Tonsillectomy , Anesthesia, Inhalation
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