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1.
Neuroimage ; 276: 120200, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37245560

RESUMEN

Anticipating social stress evokes strong reactions in the organism, including interoceptive modulations. However, evidence for this claim comes from behavioral studies, often with inconsistent results, and relates almost solely to the reactive and recovery phase of social stress exposure. Here, we adopted an allostatic-interoceptive predictive coding framework to study interoceptive and exteroceptive anticipatory brain responses using a social rejection task. We analyzed the heart-evoked potential (HEP) and task-related oscillatory activity of 58 adolescents via scalp EEG, and 385 human intracranial recordings of three patients with intractable epilepsy. We found that anticipatory interoceptive signals increased in the face of unexpected social outcomes, reflected in larger negative HEP modulations. Such signals emerged from key brain allostatic-interoceptive network hubs, as shown by intracranial recordings. Exteroceptive signals were characterized by early activity between 1-15 Hz across conditions, and modulated by the probabilistic anticipation of reward-related outcomes, observed over distributed brain regions. Our findings suggest that the anticipation of a social outcome is characterized by allostatic-interoceptive modulations that prepare the organism for possible rejection. These results inform our understanding of interoceptive processing and constrain neurobiological models of social stress.


Asunto(s)
Interocepción , Estatus Social , Adolescente , Humanos , Encéfalo/fisiología , Potenciales Evocados/fisiología , Electroencefalografía , Corazón , Interocepción/fisiología
2.
J Sci Food Agric ; 103(4): 2047-2056, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36461135

RESUMEN

BACKGROUND: The present study focused on the effect of isothermal treatment (5-90 °C) and pH (2.0-6.0) of aqueous olive leaf phenolic extract solutions on the kinetics of degradation of single and total phenolic compounds and radical scavenging activity, with the objective of predicting and optimizing the thermal treatments in foods enriched with olive leaf extracts. RESULTS: The major compound, oleuropein, showed higher degradation at low pH 2.0 and temperature-dependent reaction rates, which fitted well a first-order kinetic model, with an estimated activation energy of 98.03 ± 0.08 kJ mol-1 . Oleuropein hydrolysis resulted in a zero-order increase in hydroxytyrosol concentration at same pH (Ea  = 71.59 ± 1.5 kJ mol-1 ), whereas a 100-fold slower degradation rate was observed at higher pH. Verbascoside was only degraded at pH 6.0, also following first-order kinetics. These changes in oleuropein and hydroxytyrosol concentrations led to significant changes in fluorescence maximum intensities centered around 315 and 360 nm and in the 425-500 nm spectral zone for samples at pH 6.0, which could be associated with verbacoside degradation. Conversely, analysis of total phenolic content and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity showed little changes, indicating a rather constant overall reducing capacity of the resulting pool of compounds after thermal treatments. CONCLUSION: The present study can contribute to the knowledge related to oleuropein and phenolic fraction degradation as a result of matrix (pH) and processing. The kinetic parameters obtained could be applied for predicting and optimizing the thermal treatments in foods and drinks enriched with olive leaf extracts. © 2022 Society of Chemical Industry.


Asunto(s)
Antioxidantes , Olea , Antioxidantes/química , Calor , Iridoides/química , Fenoles/química , Olea/química , Extractos Vegetales/química , Concentración de Iones de Hidrógeno , Hojas de la Planta
3.
J Sci Food Agric ; 102(4): 1736-1743, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34403496

RESUMEN

BACKGROUND: Bread represents a significant share of food waste worldwide. The extension of the bread shelf life together with innovative systems of food waste treatment might decrease waste biomass decay, the need for transportation, and the need for storage. In recent years, insects have been selected as a valuable tool for food waste treatment owing to their capability to transform low-value food waste into biomass with high nutritional value. Bakery wastes can be used profitably for this purpose. This work had two objectives: (i) to measure the impact of flaxseed cake fortification on bread shelf life depending on the leavening agent (baker's yeast vs sourdough); (ii) to evaluate the possible reuse of the stale bread fortified with flaxseed cake for Tenebrio molitor rearing. RESULTS: Our results showed that fortification seemed to slow the hardening rate of bread, particularly if baker's yeast was used. The time necessary for mold to appear in sourdough bread doubled (from 2 to 4 days). The addition of flaxseed cake to the recipe determined an increase of its scrap consumption by T. molitor larvae. We also observed a significant increase in the body mass of the T. molitor larvae fed with bread obtained with the brewer's yeast with respect to larvae fed with the sourdough. CONCLUSION: Taken together, these preliminary data can indicate that sourdough bread fortified with 5% of flaxseed cake can represent a promising tool to reduce food waste and to recycle bread scraps by a novel zero-waste approach. © 2021 Society of Chemical Industry.


Asunto(s)
Lino , Eliminación de Residuos , Tenebrio , Animales , Pan , Fermentación , Larva
4.
Neuromodulation ; 23(2): 245-251, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31070832

RESUMEN

OBJECTIVE: To quantify the relationship between the electrical power requirement to achieve pain relief and the position of the active electrode of dorsal root ganglion stimulators within the spinal nerve root exit foramen. MATERIALS AND METHODS: Retrospective analysis of prospectively collected data of 92 consecutive patients undergoing dorsal root ganglion stimulation (DRGS) for chronic pain in a single center. Cervical and sacral cases, and failed trials/explanted DRGS were excluded, so we report on 57 patients with 78 implanted leads. Anteroposterior and lateral fluoroscopic images of the lead in the exit foramen were examined, and the active electrode positions were put into categories depending on their location relative to fixed anatomical landmarks. The clinical outcome and the power requirements for each of these groups of electrodes were then analyzed. Overall pain outcome was assessed by numeric pain rating scale score pre-operatively and post-operatively. RESULTS: There was no significant relationship between power requirements and mediolateral electrode position, although the lowest average was observed with electrode positions directly below the center of the pedicle. On lateral x-ray, the lowest power requirements were observed in the electrodes positioned superodorsally or dorsally within the foramen. Importantly, power requirements in this location were consistently low, while the power requirements in other locations were not only higher but also much more variable. Electrodes in the superodorsal position required a median output power almost four times lower than electrodes in other positions (p = 0.002). Clinical outcome was not significantly related to power requirement or foraminal position. CONCLUSION: Aiming for a superodorsal electrode position on lateral intraoperative fluoroscopy is desirable, since siting leads in this location reduces the required stimulator output power very substantially and thus will extend battery life. Position within the foramen does not determine clinical outcome, and so the implanter can safely aim for the low power site without detriment to the analgesic efficacy of the system.


Asunto(s)
Ganglios Espinales/diagnóstico por imagen , Neuroestimuladores Implantables/normas , Manejo del Dolor/normas , Dolor/diagnóstico por imagen , Estimulación de la Médula Espinal/normas , Raíces Nerviosas Espinales/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Manejo del Dolor/instrumentación , Estudios Prospectivos , Estudios Retrospectivos , Estimulación de la Médula Espinal/instrumentación , Adulto Joven
5.
Neuromodulation ; 22(5): 645-652, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30629320

RESUMEN

BACKGROUND: Trigeminal Neuropathic Pain (TNP) is a chronic facial pain syndrome caused by a lesion or disease affecting one or more branches of the trigeminal nerve. It may, for example, result from accidental injury to a branch of the trigeminal nerve by trauma or during surgery; it may also be idiopathic. TNP is typically constant, in contrast to most cases of the commoner trigeminal neuralgia. In some cases, pain may be refractory to pharmacological treatment. Peripheral nerve field stimulation is recognized as an effective minimally invasive surgical treatment option for this debilitating condition. To date, stimulation has used conventional tonic waveforms, which generate paraesthesia in the stimulated area. This is the first report of the use of paraesthesia-free burst pattern stimulation for TNP. METHODS: Seven patients were treated at the John Radcliffe Hospital for TNP from 2016 to 2018. Mean duration of preoperative symptoms was five years. All patients had exhausted pharmacological measures to limited effect. The initial three patients had tonic stimulation with the subsequent four having burst stimulation. Outcome was assessed using the numeric pain rating scale preoperatively and postoperatively at three and six months and one year. Side-effects and complications were also assessed as well as reduction in analgesic medication use. RESULTS: All patients achieved pain reduction of at least 50% at 6 months (range 50-100%, mean 81%, p = 0.0082). Those in the burst stimulation group were paraesthesia free. One patient developed a postoperative infection for which the system had to be removed and is awaiting reimplantation. There were no other complications in either group. CONCLUSION: Burst stimulation conferred similar pain control to tonic stimulation in our small cohort, and there were similar reductions in pain medication use. An additional benefit of burst stimulation is freedom from paraesthesia. Larger scale studies are needed to further evaluate burst stimulation and compare its efficacy with that of tonic stimulation.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Neuralgia Facial/terapia , Manejo del Dolor/métodos , Nervios Periféricos/fisiología , Estimulación Eléctrica Transcutánea del Nervio/métodos , Neuralgia del Trigémino/terapia , Adulto , Anciano , Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Neuralgia Facial/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Manejo del Dolor/instrumentación , Estimulación Eléctrica Transcutánea del Nervio/instrumentación , Resultado del Tratamiento , Neuralgia del Trigémino/diagnóstico por imagen
6.
Neuromodulation ; 22(5): 638-644, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31199547

RESUMEN

BACKGROUND: Occipital nerve stimulation (ONS) is widely used for headache syndromes including chronic migraine (CM) and chronic cluster headache (CCH). The paraesthesia associated with tonic stimulation can be bothersome and can limit therapy. It is now clear in spinal cord stimulation that paraesthesia-free waveforms can produce effective analgesia, but this has not been reported in ONS for CM or CCH. MATERIALS AND METHODS: Seventeen patients (12 CM and 5 CCH) were treated with bilateral burst pattern ONS, including 4 who had previously had tonic ONS. Results were assessed in terms of the frequency of headaches (number of headache days per month for CM, and number of attacks per day for CCH) and their intensity on the numeric pain rating scale. RESULTS: Burst ONS produced a statistically significant mean reduction of 10.2 headache days per month in CM. In CCH, there were significant mean reductions in headache frequency (92%) and intensity (42%). CONCLUSION: Paraesthesia is not necessary for good quality analgesia in ONS. Larger studies will be required to determine whether the efficacies of the two stimulation modes differ. Burst ONS is imperceptible and therefore potentially amenable to robustly blinded clinical trials.


Asunto(s)
Cefalalgia Histamínica/terapia , Terapia por Estimulación Eléctrica/métodos , Trastornos Migrañosos/terapia , Manejo del Dolor/métodos , Nervios Periféricos/fisiología , Adulto , Anciano , Enfermedad Crónica , Cefalalgia Histamínica/diagnóstico , Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Migrañosos/diagnóstico , Manejo del Dolor/instrumentación , Estudios Retrospectivos
7.
Hippocampus ; 27(5): 547-557, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28176408

RESUMEN

The detection and processing of novel information encountered in our environment is crucial for proper adaptive behavior and learning. Hippocampus is a prime structure for novelty detection that receives high-level inputs including context information. It is of our interest to understand the mechanisms by which the hippocampus processes contextual information. For this, we performed in vivo microdyalisis in order to monitor extracellular changes in neurotransmitter levels during Object Location Memory (OLM), a behavioral protocol developed to evaluate contextual information processing in recognition memory. Neurotransmitter release was evaluated in the dorsal hippocampus and insular cortex during OLM in 3-month-old B6129SF2/J mice. We found a simultaneous release of dopamine and norepinephrine in hippocampus during OLM, while neurochemical activity remained unaltered in the cortex. Additionally, we administered 6-hydroxy-dopamine (6-OHDA), a neurotoxic compound selective to dopaminergic and noradrenergic neurons, in the dorsal hippocampus in a different group of mice. Depletion of catecholaminergic terminals in the hippocampus by 6-OHDA impaired OLM but did not affect novel object recognition. Our results support the relevance of hippocampal catecholaminergic neurotransmission in recognition memory. The significance of catecholaminergic function may be extended to the clinical field as it has been reported that innervation of hippocampus by the noradrenergic and dopaminergic system is reduced and atrophied in aging and Alzheimer's disease brain. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Dopamina/metabolismo , Hipocampo/metabolismo , Norepinefrina/metabolismo , Reconocimiento en Psicología/fisiología , Memoria Espacial/fisiología , Animales , Catéteres de Permanencia , Electroforesis Capilar , Conducta Exploratoria/fisiología , Inmunohistoquímica , Masculino , Memoria a Largo Plazo/fisiología , Ratones de la Cepa 129 , Microdiálisis , Pruebas Neuropsicológicas , Oxidopamina/toxicidad , Patrones de Reconocimiento Fisiológico/fisiología
8.
Acta Neurochir (Wien) ; 159(8): 1571-1576, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28526902

RESUMEN

Retroclival epidural haematoma (REDH) has been reported infrequently. It is a rare entity which is probably underdiagnosed. It is most commonly seen in the paediatric population and is generally associated with high-velocity injuries. We report three cases of paediatric patients diagnosed with REDHs: two of them secondary to high-energy trauma related to a motor-vehicle accident and the other a low-energy trauma after a slip while playing football. All three patients were managed conservatively by cervical immobilisation with favourable outcome. REDH is probably underdiagnosed by computed tomography scan. When the suspicion is high, sagittal reconstructions or magnetic resonance imaging should be considered to confirm the diagnosis. Usually, it is related to hyperflexion or hyperextension cervical injuries secondary to motor vehicle accident. However, it can also be observed in milder injuries.


Asunto(s)
Hematoma Epidural Craneal/diagnóstico por imagen , Accidentes de Tránsito , Traumatismos en Atletas , Niño , Hematoma Epidural Craneal/etiología , Hematoma Epidural Craneal/terapia , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos X/métodos
9.
Neurocirugia (Astur) ; 26(5): 251-5, 2015.
Artículo en Español | MEDLINE | ID: mdl-25579309

RESUMEN

We report the case of a 32-year-old patient complaining of chronic low back pain radiating to his left thigh. His MRI showed a lytic L1 vertebral body injury. A transpedicular biopsy confirmed the diagnosis of giant cell tumor. He underwent a L1 vertebrectomy and vertebral body replacement with a titanium cylinder using anterior approach, followed by the removal of the L1 posterior arch and the placement of pedicle screws through a posterior approach. The giant cell tumor is a rare benign primary bone tumor that can be locally aggressive and can potentially spread to other areas, usually to the lungs. Although it most frequently affects long bones, approximately 10% of tumors are located in the spine. To minimise the risk of recurrence, the elective management option is surgery.


Asunto(s)
Tumores de Células Gigantes/diagnóstico , Dolor de la Región Lumbar/etiología , Neoplasias de la Columna Vertebral/diagnóstico , Adulto , Tumores de Células Gigantes/cirugía , Humanos , Vértebras Lumbares/cirugía , Masculino , Neoplasias de la Columna Vertebral/cirugía
10.
Langmuir ; 30(46): 14062-72, 2014 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-25360639

RESUMEN

The Maillardation of proteins has been used as a natural alternative to improve its functionality by covalent coupling of proteins with saccharides. However, the impact of Maillard reaction on the structural aspects of protein networks and, as a consequence, the mechanical breakdown properties of the gel networks has not been reported. The objective of this study was to evaluate how the attachment of linear oligo-sugar moieties onto ovalbumin affects its aggregation, network morphology, and consequently the mechanical deformation properties including the ability of the networks to elastically store energy in this material. To potentially alter the morphology of the network structure, ovalbumin was modified by conjugating some of its amino groups with fructooligosaccharide (FOS) moieties via the Maillard reaction. It was demonstrated that the attachment of FOS to ovalbumin does not affect the integrity of the secondary and tertiary structure as characterized using circular dichroism and tryptophan fluorescence. Differences in the network morphology were observed by scanning electron microscopy for FOS-modified ovalbumin variants. Upon increased modification, the microstructure of the gels had more and larger pores and had thinner strands than nonmodified variants. Evaluation of the large deformation properties of the gels demonstrated that FOS-modified gels were less strong and less brittle and showed lower stiffness than nonmodified variants. The recoverable energy (elastically stored energy) of gels reduced with an increase in the degree of modification. The results show that the attachment of FOS to ovalbumin alters the structural and mechanical (large) breakdown properties of the protein gels. The consequences of the alteration of the network structure and large deformation properties of FOS-modified ovalbumin offer opportunities to efficiently design food materials with desirable techno-functional applications.


Asunto(s)
Reacción de Maillard , Oligosacáridos/química , Ovalbúmina/química , Agregado de Proteínas
11.
Science ; 383(6687): 1040, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38452083

RESUMEN

Task force says museum should return many of its 30,000 remains and seek descendants' consent for research.


Asunto(s)
Restos Mortales , Museos , Humanos , Estados Unidos
12.
Science ; 384(6695): 500-504, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38696575

RESUMEN

If elected, Claudia Sheinbaum Pardo would bring an extensive background in science and engineering to Mexico's presidency. But many researchers are anxious about how she would govern.

13.
Science ; 384(6703): 1397, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38935721

RESUMEN

Researchers see creation of new high-level science secretariat as a "good sign".

14.
Science ; 379(6635): 870-873, 2023 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-36862779

RESUMEN

Implicit bias can degrade health care. Now, researchers are finding new ways to recognize and mitigate it.


Asunto(s)
Sesgo Implícito , Instituciones de Salud , Humanos , Investigadores
15.
Science ; 381(6656): 363-364, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37499020

RESUMEN

Mütter Museum launches an ethical review of its anatomical curiosities-and sets off a firestorm.

16.
Science ; 381(6662): 1040-1041, 2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37676949

RESUMEN

Zoologists debate whether-and how-to change scientific names now deemed offensive.


Asunto(s)
Escarabajos , Zoología , Animales , Escarabajos/clasificación , Nombres , Alemania , Zoología/clasificación
17.
Science ; 380(6650): 1097, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37319210

RESUMEN

Research links structural racism of 1900s U.S. society to striking disparities in childhood mortality.


Asunto(s)
Negro o Afroamericano , Mortalidad del Niño , Disparidades en el Estado de Salud , Racismo , Segregación Social , Humanos , Negro o Afroamericano/historia , Racismo/historia , Segregación Social/historia , Estados Unidos , Blanco , Mortalidad del Niño/historia , Niño
18.
Science ; 382(6667): 144-149, 2023 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-37824666

RESUMEN

Mexican biologist Rodrigo Medellín Legorreta is fighting political headwinds to preserve his country's natural heritage-and his own legacy.


Asunto(s)
Quirópteros , Especies en Peligro de Extinción , Extinción Biológica , Animales , México
19.
Antioxidants (Basel) ; 12(2)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36830001

RESUMEN

In this study, freeze-drying microencapsulation was proposed as a technology for the production of powdered hop extracts with high stability intended as additives/ingredients in innovative formulated food products. The effects of different carriers (maltodextrin, Arabic gum, and their mixture in 1:1 w/w ratio) on the physical and techno-functional properties, bitter acids content, yield and polyphenols encapsulation efficiency of the powders were assessed. Additionally, the powders' stability was evaluated for 35 days at different temperatures and compared with that of non-encapsulated extract. Coating materials influenced the moisture content, water activity, colour, flowability, microstructure, and water sorption behaviour of the microencapsulates, but not their solubility. Among the different carriers, maltodextrin showed the lowest polyphenol load yield and bitter acid content after processing but the highest encapsulation efficiency and protection of hop extracts' antioxidant compounds during storage. Irrespective of the encapsulating agent, microencapsulation did not hinder the loss of bitter acids during storage. The results of this study demonstrate the feasibility of freeze-drying encapsulation in the development of functional ingredients, offering new perspectives for hop applications in the food and non-food sectors.

20.
Science ; 376(6591): 335, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35446639

RESUMEN

Study suggests feathers arose-and were used for display-well before reign of dinosaurs.


Asunto(s)
Dinosaurios , Fósiles , Animales , Dinosaurios/anatomía & histología , Plumas
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