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1.
Phys Rev Lett ; 132(18): 182502, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38759198

RESUMO

The observation of neutrinoless double-beta (0νßß) decay would offer proof of lepton number violation, demonstrating that neutrinos are Majorana particles, while also helping us understand why there is more matter than antimatter in the Universe. If the decay is driven by the exchange of the three known light neutrinos, a discovery would, in addition, link the observed decay rate to the neutrino mass scale through a theoretical quantity known as the nuclear matrix element (NME). Accurate values of the NMEs for all nuclei considered for use in 0νßß experiments are therefore crucial for designing and interpreting those experiments. Here, we report the first comprehensive ab initio uncertainty quantification of the 0νßß-decay NME, in the key nucleus ^{76}Ge. Our method employs nuclear strong and weak interactions derived within chiral effective field theory and recently developed many-body emulators. Our result, with a conservative treatment of uncertainty, is an NME of 2.60_{-1.36}^{+1.28}, which, together with the best-existing half-life sensitivity and phase-space factor, sets an upper limit for effective neutrino mass of 187_{-62}^{+205} meV. The result is important for designing next-generation germanium detectors aiming to cover the entire inverted hierarchy region of neutrino masses.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38070871

RESUMO

Record-breaking levels of asylum seeking by families with young children continue at the United States/Mexico border, particularly the Rio Grande Valley sector. In this Commentary, our aim is to increase awareness by providing child and adolescent mental health care providers with an update on current migrant conditions, bringing to light issues of family separation previously highlighted in the Journal.1 For context, our international group has collected data, via 3 large-scale studies funded by the National Institutes of Health, from more than 600 Latinx immigrants seeking asylum at the US/Mexico border in the last 4 years, during which levels of violence, climate disruption, and poverty in the Northern Triangle of Central America (ie, El Salvador, Guatemala, and Honduras) and Mexico have propelled high and sustained levels of asylum seeking in the United States. We contribute expertise in clinical psychology, Latinx psychology, attachment disruption, and public health, as well as this front-row perspective.

4.
Biophys Chem ; 292: 106910, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36327692

RESUMO

Porous Silicon (PSi) is an ideal material to build biosensors due to its large surface area and biocompatibility. However, it lacks of selectivity. By adhering bilayer lipids, active sites are added for vital biochemical processes. Such processes are promoted by different proteins, which aid to detect pollutants and drugs, among other. The present work is a systematic theoretical study at the density functional theory level on PSi models, functionalized with H and OH. Several concentrations of such functional groups were assessed at the pores to elucidate the reactivity via Fukui indexes of electrophilic and nucleophilic attack. The 1,2-dimyristoyl-sn-glycero-3-phosphocholine(DMPC) lipid was used as a probe system to interact with the PSi. The attraction was evaluated as electrostatic with a van der Waals contribution. The adsorption was highly selective to the degree of functionalization at the pore. The PSi facets (100) and (001) showed different mechanisms of interaction with the DMPC lipid. The theoretical absorption spectra addressed that the DMPC lipid could be identified with intensity variations coming from the degree of functionalization at the pore, which may be further rationalized experimentally. The present methodology may aid to tailor novel materials to capture and identify adverse agents present in the environment.


Assuntos
Dimiristoilfosfatidilcolina , Bicamadas Lipídicas , Humanos , Dimiristoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Silício , Porosidade , Eletricidade Estática
5.
Rev. Fac. Odontol. (B.Aires) ; 38(89): 75-82, 2023. ilus
Artigo em Espanhol | LILACS | ID: biblio-1553394

RESUMO

Desórdenes sistémicos de la homeostasis mineral o fallas en la mineralización de la matriz extracelular pueden afectar tanto a las piezas dentarias como a su aparato de sostén, conduciendo al fracaso de los tratamientos odontológicos. Existe poca evidencia científica sobre modelos animales que permitan es-tudiar la respuesta de tejidos dentarios/paradenta-rios frente a este tipo de desórdenes. El objetivo del presente trabajo fue estudiar experimentalmente al-teraciones de la biomineralización inducidas por bis-fosfonatos en ratas Wistar. Para ello, 20 ratas Wistar hembras y machos (35±10 g) fueron tratados con 20 mg/kg de etidronato bisódico (EHBP) o solución fi-siológica (control) vía intraperitoneal 5 veces por se-mana durante 3 semanas. Luego de la eutanasia, se extrajeron las mandíbulas para su procesamiento y análisis histológico (H&E). Mediante microfotografías digitales se evaluó: área ósea/área total, espesor de ligamento periodontal, áreas de dentina y de cemen-to. Los resultados se analizaron estadísticamente mediante el test T de Student para comparaciones entre grupos y el test ANOVA de 2 vías para las com-paraciones intersexo. Los grupos EHBP presentaron mayor proporción de osteoide, dentina y cemento no mineralizados respecto a los controles, siendo más marcadas las diferencias en las hembras. Las hem-bras del grupo EHBP mostraron una disminución significativa en el espesor del ligamento periodontal respecto de los controles, aunque esta tendencia no se observó en machos. Los resultados del presente estudio demuestran que el EHBP, en la dosis y tiempo estudiados, altera los procesos de biomineralización tanto del tejido óseo como de los tejidos dentarios (AU)


Systemic disorders of mineral homeostasis or alterations in the mineralization of the extracellular matrix can affect both dental and supportive tissues, leading to the failure of dental treatments. There is a lack of scientific information about animal models that allow to study the response of dental/paradental tissues in this type of disorders. The aim of the present work was to study the biomineralization alterations induced by bisphosphonates in Wistar rats and to study the response of dental and paradental tissues. Twenty Wistar rats (35±10 g) were divided in control (females, males) and EHBP (females, males) groups. The EHBP group received 20 mg/kg of ethidronate bisodium intraperitoneally 5 times a week for 3 weeks, while the control group received saline solution. After euthanasia, mandibles were resected and processed histologically to obtained oriented sections for H&E staining. Photomicrographs were used to evaluate: Bone area/total area, periodontal ligament thickness, dentin and cement area. Results were statistically analyzed using the Student's T test for comparisons between groups and the 2-way ANOVA test for male and female comparisons. The EHBP groups showed a higher amount of non-mineralized osteoid, dentin and cement compared to control groups, being more evident in females. Females in the EHBP group showed a significant decrease in periodontal ligament thickness compared to controls, although this profile was not observed in males. The results of the present study demonstrate that EHBP, at the dose and time studied, alters the biomineralization processes of both bone and dental tissues (AU)


Assuntos
Animais , Ratos , Dente/efeitos dos fármacos , Difosfonatos/efeitos adversos , Biomineralização/efeitos dos fármacos , Interpretação Estatística de Dados
6.
Rev Neurol ; 75(7): 173-180, 2022 10 01.
Artigo em Espanhol | MEDLINE | ID: mdl-36169323

RESUMO

INTRODUCTION: Cognitive reserve is the ability to better tolerate brain damage through pre-existing and compensatory cognitive resources. One assessment method is the Rami CRQ-Cognitive Reserve Questionnaire. The objective was to carry out an analysis of the informative quality of the CRQ from the item response theory (IRT), in order to provide more precise data on the reliability of internal consistency. Convergent validity was also tested with measures of attention, working memory, and fluency. SUBJECTS AND METHODS: 210 Argentines from the general population (mean age, 66.8 years) participated. The CRQ was administered together with the digits test and three fluency tasks. A graded response model was fitted from IRT with estimation of discrimination parameters (a) and difficulty (b), and a CRQ information curve was created. Bivariate and partial correlations were made. RESULTS: The IRT indicated high discrimination for the CRQ items 'Education' and 'Occupation level' (both for the 8-item version and the 6-item version). In the CRQ of 8 items, low discrimination was obtained for 'Musical training' and 'Intellectual games'. In both versions of the CRQ, the curve indicates greater informational value at a low level of the construct. There was a correlation with the digits test and with fluency tasks, even when controlling for age. CONCLUSIONS: This study is the first analysis of CRQ from IRT, concluding that the instrument is more reliable when applied to subjects with less reserve. The CRQ has acceptable convergent validity.


TITLE: Cuestionario de reserva cognitiva: análisis psicométrico desde la teoría de respuesta al ítem.Introducción. La reserva cognitiva es la capacidad para tolerar mejor el daño cerebral mediante recursos cognitivos preexistentes y compensatorios. Un método de evaluación es el cuestionario de reserva cognitiva (CRC) de Rami. El objetivo fue realizar un análisis de la calidad informativa del CRC desde la teoría de respuesta al ítem (TRI), con el fin de aportar datos más precisos sobre la fiabilidad de consistencia interna. Se probó, además, la validez convergente con medidas de atención, memoria de trabajo y fluidez. Sujetos y métodos. Participaron 210 argentinos de población general (media edad, 66,8 años). El CRC se administró junto con el test de dígitos y tres tareas de fluidez. Se ajustó un modelo de respuesta graduada desde la TRI con estimación de parámetros de discriminación (a) y dificultad (b), y se elaboró una curva de información del CRC. Se efectuaron correlaciones bivariadas y parciales. Resultados. La TRI indicó una alta discriminación para los ítems del CRC 'Escolaridad' y 'Nivel de ocupación' (tanto para la versión de ocho ítems como para la versión de seis ítems). En el CRC de ocho ítems se obtuvo una baja discriminación para 'Formación musical' y 'Juegos intelectuales'. En ambas versiones del CRC, la curva indica mayor valor informacional a bajo nivel del constructo. Hubo correlación con el test de dígitos y con las tareas de fluidez, incluso al controlar por edad. Conclusiones. El presente estudio es el primer análisis del CRC desde la TRI, que concluye que el instrumento resulta más confiable cuando se aplica a sujetos con menor reserva. El CRC posee aceptable validez convergente.


Assuntos
Reserva Cognitiva , Idoso , Humanos , Psicometria , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
7.
Rehabilitacion (Madr) ; 56(4): 353-363, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35523617

RESUMO

OBJECTIVE: A systematic review is presented with the objective of determining whether school children with congenital heart disease participate in psychological interventions in the cardiovascular rehabilitation process. METHOD: Guided review by the PRISMA method was carried out in the databases: Dialnet, Pub Med, Redalyc, Science Direct, Scielo, Google Academic of articles published in English, Portuguese and Spanish. The inclusion criteria are: rehabilitative interventions that contain actions for the management of psychological factors. 23 reports were evaluated for eligibility, only 1 was chosen through the data tabulation method. RESULTS: It was evidenced that these programs for children with heart disease are scarce, they focus on physical activity, neglecting socio-psychological variables. It is proposed to implement standardized intervention actions with congenital cardiovascular patients and their families from psychocardiology according to their needs.


Assuntos
Reabilitação Cardíaca , Cardiopatias Congênitas , Criança , Exercício Físico , Humanos
10.
J Fr Ophtalmol ; 44(10): 1516-1522, 2021 Dec.
Artigo em Francês | MEDLINE | ID: mdl-34774347

RESUMO

INTRODUCTION: Assisted living residents are a fragile population with limited access to health care. In recent years, telemedicine has developed in several specialties, including ophthalmology. The main objective of our study is the validation of an ophthalmology telemedicine protocol in assisted living facilities. MATERIALS AND METHODS: This is a retrospective, multicentric, descriptive study including 4 assisted living facilities in the Rennes area. An ophthalmic technician examined residents for one half-day per week. The examination was performed directly in the patient's room, in bed or in a chair, with portable equipment. An ophthalmologist from our service interpreted the results remotely on a deferred basis within 7 days. Appropriate medical or surgical care was then offered to the patient depending on the diagnosis. RESULTS: We included 113 residents. A complete, interpretable examination was achieved in 84.1% of cases. One or more ophthalmic conditions were diagnosed in 57.5% of the residents. Of the residents who were then seen at the university medical center, 65% underwent a scheduled surgical procedure or laser. Visual acuity was significantly improved subsequent to the telemedicine encounter. DISCUSSION: The success rate of a complete, interpretable examination allows us to now validate our nursing home examination procedure. In addition to bringing a large amount of initially unknown information to the medical and paramedical staff of the structure, ophthalmology telemedicine allows for a significant improvement in visual acuity. CONCLUSION: This project validated the feasibility of ophthalmology telemedicine in an assisted living setting. This protocol may also be applicable to other health care settings (penitentiaries, mental health institutions, etc.).


Assuntos
Oftalmopatias , Oftalmologia , Telemedicina , Humanos , Casas de Saúde , Estudos Retrospectivos
11.
Rev Neurol ; 73(6): 194-200, 2021 Sep 01.
Artigo em Espanhol | MEDLINE | ID: mdl-34515332

RESUMO

INTRODUCTION: Cognitive reserve is the brain's capacity to actively overcome damage by means of pre-existing cognitive resources and compensatory processes. This capacity is enhanced by education, occupational attainment, learning languages and the habit of reading, among other important factors. This study aimed to investigate the psychometric properties of Rami et al's Cognitive Reserve Questionnaire in an Argentinian population. MATERIALS AND METHODS: The sample that participated in the study comprised 203 Argentinian adult volunteers from the general population (mean age, 66.1; standard deviation, 8.1). The Cognitive Reserve Questionnaire was administered together with the Montreal Cognitive Assessment. Confirmatory factor analysis was carried out to test the unidimensionality of the questionnaire. In addition, reliability was estimated by the categorical omega coefficient and associative validity was analysed by means of bivariate correlations. RESULTS: Factor analysis confirms the unidimensionality of the questionnaire with good fit indices. Items 5 (musical training) and 8 (intellectual games), however, show low factor loadings. The test has acceptable reliability, with a categorical omega coefficient = 0.72, although it should be noted that the average variance extracted (0.41) is below the recommended criterion of 0.5. Good associative validity is observed: r (200) = 0.4; p < 0.001. CONCLUSIONS: The Cognitive Reserve Questionnaire is an instrument with acceptable psychometric properties for use in an Argentinian population. More research is required to further investigate the low factor loadings of items 5 and 8 and to strengthen the evidence of reliability.


TITLE: Cuestionario de reserva cognitiva: propiedades psicométricas en población argentina.Introducción. La reserva cognitiva es la capacidad del cerebro para superar activamente el daño por intermedio de recursos cognitivos preexistentes y procesos compensatorios. Dicha capacidad es incrementada por la educación, el logro ocupacional, el aprendizaje de idiomas y el hábito de lectura, entre otros importantes factores. Este estudio tuvo como objetivo investigar las propiedades psicométricas del Cuestionario de Reserva Cognitiva de Rami et al en población argentina. Sujetos y métodos. Participaron 203 personas voluntarias adultas argentinas de población general (edad media, 66,1; desviación estándar, 8,1). Se administró el Cuestionario de Reserva Cognitiva junto con la Evaluación Cognitiva de Montreal. Se efectuó un análisis factorial confirmatorio para poner a prueba la unidimensionalidad del cuestionario. Además, se estimó la confiabilidad por el coeficiente omega categórico y se analizó la validez asociativa mediante correlaciones bivariadas. Resultados. El análisis factorial confirma la unidimensionalidad del cuestionario con buenos índices de ajuste. Sin embargo, los ítems 5 (formación musical) y 8 (juegos intelectuales) presentan baja carga factorial. La prueba posee una aceptable confiabilidad, con un coeficiente omega categórico = 0,72, aunque cabe advertir que la varianza extraída promedio (0,41) se ubica por debajo del criterio recomendado de 0,5. Se observa una buena validez asociativa ­r (200) = 0,4; p menor de 0,001­. Conclusiones. El Cuestionario de Reserva Cognitiva es un instrumento con aceptables propiedades psicométricas para su uso en población argentina. Serán convenientes nuevas investigaciones que profundicen en la baja carga factorial de los ítems 5 y 8 y refuercen las evidencias de fiabilidad.


Assuntos
Reserva Cognitiva , Testes Psicológicos , Idoso , Argentina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria
15.
J Investig Allergol Clin Immunol ; 31(5): 364-384, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34045179

RESUMO

Rapid drug desensitization has enabled first-line therapies in patients with drug hypersensitivity reactions to chemotherapeutic drugs including monoclonal antibodies. Desensitization is a safe and highly effective procedure, not only for IgE-mediated reactions, but also for those mediated by non-IgE mechanisms. The likelihood of breakthrough reactions during desensitization is low, and most are mild; in fact, moderate-to-severe reactions are infrequent. In this document, 16 allergy departments belonging to the Spanish research network ARADyAL present a review of the available scientific evidence and provide general guidelines for the diagnosis and management of drug hypersensitivity reactions to chemotherapeutic drugs and monoclonal antibodies. Emphasis is placed on the desensitization procedure.


Assuntos
Antineoplásicos Imunológicos , Hipersensibilidade a Drogas , Neoplasias , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Dessensibilização Imunológica , Hipersensibilidade a Drogas/tratamento farmacológico , Hipersensibilidade a Drogas/terapia , Humanos , Neoplasias/tratamento farmacológico
16.
Phys Rev Lett ; 126(7): 072501, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666458

RESUMO

We studied the proton-rich T_{z}=-1 nucleus ^{70}Kr through inelastic scattering at intermediate energies in order to extract the reduced transition probability, B(E2;0^{+}→2^{+}). Comparison with the other members of the A=70 isospin triplet, ^{70}Br and ^{70}Se, studied in the same experiment, shows a 3σ deviation from the expected linearity of the electromagnetic matrix elements as a function of T_{z}. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei ^{70}Kr and ^{70}Se contrary to the model predictions.

17.
Phys Rev Lett ; 124(23): 232501, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603157

RESUMO

Working with Hamiltonians from chiral effective field theory, we develop a novel framework for describing arbitrary deformed medium-mass nuclei by combining the in-medium similarity renormalization group with the generator coordinate method. The approach leverages the ability of the first method to capture dynamic correlations and the second to include collective correlations without violating symmetries. We use our scheme to compute the matrix element that governs the neutrinoless double beta decay of ^{48}Ca to ^{48}Ti, and find it to have the value 0.61, near or below the predictions of most phenomenological methods. The result opens the door to ab initio calculations of the matrix elements for the decay of heavier nuclei such as ^{76}Ge, ^{130}Te, and ^{136}Xe.

18.
Phys Rev Lett ; 124(22): 222501, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32567911

RESUMO

Here we present new information on the shape evolution of the very neutron-rich ^{92,94}Se nuclei from an isomer-decay spectroscopy experiment at the Radioactive Isotope Beam Factory at RIKEN. High-resolution germanium detectors were used to identify delayed γ rays emitted following the decay of their isomers. New transitions are reported extending the previously known level schemes. The isomeric levels are interpreted as originating from high-K quasineutron states with an oblate deformation of ß∼0.25, with the high-K state in ^{94}Se being metastable and K hindered. Following this, ^{94}Se is the lowest-mass neutron-rich nucleus known to date with such a substantial K hindrance. Furthermore, it is the first observation of an oblate K isomer in a deformed nucleus. This opens up the possibility for a new region of K isomers at low Z and at oblate deformation, involving the same neutron orbitals as the prolate orbitals within the classic Z∼72 deformed hafnium region. From an interpretation of the level scheme guided by theoretical calculations, an oblate deformation is also suggested for the ^{94}Se_{60} ground-state band.

19.
Arch Microbiol ; 202(8): 2337-2341, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32533208

RESUMO

Pexophagy is a peroxisome degradation process. The last two steps of penicillin biosynthesis in Penicillium rubens are carried out in peroxisomes. These organelles proliferate in large numbers during this process, so that after the penicillin secretion, their removal is essential as a regulatory mechanism. In this work, two pexophagy modes are described for the high-penicillin producing strain P. rubens P2-32-T, by transmission electron microscopy (TEM) on 24- and 48-h cultures (when maximum penicillin production is achieved). The obtained images show peroxisome phagocytosis by vacuoles in three different ways: macropexophagy, micropexophagy, and a new proposed model: unipexophagy.


Assuntos
Penicilinas/biossíntese , Penicillium/metabolismo , Autofagia , Proteínas Fúngicas/metabolismo , Redes e Vias Metabólicas , Penicilinas/metabolismo , Penicillium/ultraestrutura , Peroxissomos/metabolismo , Fagocitose , Vacúolos/metabolismo
20.
Arch Microbiol ; 202(5): 1257-1262, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31953549

RESUMO

The compartmentalization of penicillin G biosynthesis in Penicillium rubens has been extensively studied. However, how this compound is secreted has not been completely elucidated, although its transport could be of the vesicular type. This work was aimed at observing vesicles and penicillin secretion and proposing a hypothetical model for their compartmentalization and secretion. For this purpose, a high-penicillin-producing strain (P. rubens P2-32-T) was compared by transmission electron microscopy (TEM) and atomic force microscopy (AFM) with a null-producing strain (P. rubens npe10) in 24- and 48-h cultures. The results showed multivesicular bodies and secretory vesicles, suggesting that P. rubens transports and secretes penicillin G through vesicular excretion.


Assuntos
Transporte Biológico , Penicilina G/metabolismo , Penicillium/metabolismo , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Penicillium/ultraestrutura
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