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1.
Neuropsychologia ; 196: 108818, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355037

RESUMO

How well do we know our city? It turns out, much more poorly than we might imagine. We used declarative memory and eye-tracking techniques to examine people's ability to detect modifications to real-world landmarks and scenes in Toronto locales with which they have had extensive experience. Participants were poor at identifying which scenes contained altered landmarks, whether the modification was to the landmarks' relative size, internal features, or relation to surrounding context. To determine whether an indirect measure would prove more sensitive, we tracked eye movements during viewing. Changes in overall visual exploration, but not to specific regions of change, were related to participants' explicit endorsement of scenes as modified. These results support the contention that very familiar landmarks are represented at a global or gist level, but not local or fine-grained, level. These findings offer a unified view of memory for gist across verbal and spatial domains, and across recent and remote memory, with implications for hippocampal-neocortical interactions.


Assuntos
Movimentos Oculares , Hipocampo , Humanos
2.
Prensa méd. argent ; 108(3): 146-150, 20220000. fig, tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1373103

RESUMO

Introducción: El colgajo pediculado realizado con músculo temporal es una opción terapéutica válida para la reconstrucción de defectos de la región facial posterior a una resección quirúrgica, es una alternativa aceptable a los colgajos libres cuando estos no pueden ser utilizados ya sea por el performance status o patología de base de los pacientes a tratar o por no contar con cirujano microvascular. Objetivo: Describir nuestra experiencia en el uso de este colgajo para la reconstrucción de 7 pacientes con defectos de órbita, paladar y mucosa yugal tras la cirugía ablativa de diversas patologías. Materiales y métodos: Revisión retrospectiva de los pacientes del Servicio de Cirugía General del Hospital José Ramon Vidal, Corrientes-Argentina operados en el periodo comprendido desde enero del 2019 hasta enero del 2021.En este lapso, 7 pacientes fueron sometidos a cirugía reconstructiva inmediata con colgajo de músculo temporal en defectos del tercio medio de la región facial. Resultados: Un total de siete pacientes, (4 masculino- 3 femenino), sometidos a cirugía ablativa por presentar patología maligna (6) y patología benigna (1), con una edad media de 60 años. Dos colgajos se utilizaron para defectos de región orbitaria y partes blandas, seis para defectos en la cavidadoral­ en un paciente se emplearon los 2 músculos temporales-. El colgajo fue exitoso en todos los casos, se presentaron complicaciones menores como: dolor postoperatorio, hematoma, trismus, depresión de la zona dadora. Se obtuvo márgenes libres en el total de los procedimientos. Discusión: La cirugía reconstructiva con colgajo pediculado de musculo temporal es una excelente alternativa de colgajo regional con buenos resultados, posee alta tasa de éxito justificada por su buena vascularización. Además, la proximidad del músculo temporal con la región maxilofacial y su inserción contribuyen a obtener un arco de rotación hasta 180° sin comprometersu vitalidad. Es útil para la reconstrucción en un acto quirúrgico, acortando el tiempo intraoperatorio y sin cambios posicionales. Conclusiones: El colgajo de músculo temporal resulta una opción válida a los colgajos libres osteo-mio-cutáneos para defectos mixtos (óseos y de partes blandas) del tercio medio facial luego de la cirugía ablativa, cuando estos últimos no pueden ser implementados teniendo en cuenta varios aspectos como performance estatus de los pacientes, patología de base y necesidad de contar con un cirujano microvascular


Introduction: temporalis muscle vascularized flaps is a valid therapeutic option for reconstruction of defects in facial region after surgical resections. It is an acceptable alternative to free transfer flaps when these cannot be used because of the patient's performance state and base pathologies. Or because of the lack of a microvascular surgeon. Objectives: To describe on experience applying this kind of flaps for the reconstruction or 7 patients, with defects in palate orbit and yugal mucose after resective surgeries for various pathologies. Materials and methods: retrospective revision of patients in the general department, of Jose R Vidal Hospital (Corrientes - Argentina) into underwent surgery during the period between January 2019 ad January 2021. A total of 7 patients underwent immediate reconstructive surgery using a temporalis muscle flap. Results: 7 patients (4 males y 3 female) underwent resective surgery for different malignant (6) and benign (1) with a median age of 60. Two flaps were used for defects of the orbitary region and soft tissue, six for defects of the oral cavity (in one patient both temporalis muscle were used. Te procedure was successful in all cases, and minor complication were present, (post operatory pain, hematoma, trismus, excavation of the donor region) all procedures resulted un surgical margins of lesion of malignancy. Discussion: reconstructive surgery using a vascularized flap of temporalis muscle is an excellent alternative for regional flaps with good results and a high success justified because of its a good irrigation. Besides the proximity between temporalis muscle and the maxillofacial region, possibilities a flap rotation of up to 180 grades without compromising its vitality it is also useful for reconstruction in a single surgery shortening intra-operatory time while avoiding repositioning of the patients during the procedure. Conclusions: Temporalis muscle flaps are valid option to free osteo- mayo- cutaneal flaps for mixed defects (involving bone and soft tissue) of the medium third of facial region after resective surgeries when the latter cannot be carried and because of various aspects little performance status base pathologies and lack of microvascular margin.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Cirurgia Bucal/métodos , Estudos Retrospectivos , Procedimentos de Cirurgia Plástica/métodos , Retalhos de Tecido Biológico/cirurgia , Músculos da Mastigação
3.
Ind Eng Chem Res ; 61(17): 6052-6056, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37538052

RESUMO

This communication proposes a preliminary simplified kinetic model for the hydrogenation of 1-phenyl-1,2-propanedione that can render up to eight compounds, involving regioselectivity and enantioselectivity. The catalytic system comprises two functionalities; the heterogeneous catalyst (Ir/TiO2) plays the role for the hydrogenation, whereas the adsorption/binding to the active site is played by a chiral molecule (cinchonidine), added to the reaction mixture. The reaction occurs at room temperature and total pressure of 40 bar. The product distribution shows competitive parallel and series pathways with up to 12 possible reactions. Despite the complexity of both reaction and catalyst system, a simplified kinetic model was able to predict the concentrations profiles. The model assumes the reactions to be apparent first order in the concentrations of reactant and intermediate products, while the kinetic constants include all other effects (partial pressure of hydrogen, solvent and catalyst effects, and the concentration of the chiral additive). The concentration profiles were well-modeled with low residual values. The errors in the kinetic constants (k-values) were small for all relevant parameters of the main reaction pathways. Two k-values are nil, which is the lower bound imposed in the model, suggesting that these reaction pathways are likely negligible. The positive outcome from this simplified model suggests that the process can be formally treated as a first-order irreversible homogeneous catalyzed reaction, despite a heterogeneous catalyst was employed (with a modifier). Despite the promising results, the model must be extended for a more general applicability, or conditions where it is applicable.

4.
Sci Rep ; 11(1): 23488, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34873196

RESUMO

Weaning is a critical period in the life of pigs with repercussions on their health and welfare and on the economy of the swine industry. This study aimed to assess the effect of the commercial early weaning on gut microbiota, intestinal gene expression and serum metabolomic response via an integrated-omic approach combining 16S rRNA gene sequencing, the OpenArray gene expression technology and 1H-NMR spectroscopy. Fourteen piglets from different litters were sampled for blood, jejunum tissue and caecal content two days before (- 2d), and three days after (+ 3d) weaning. A clearly differential ordination of caecal microbiota was observed. Higher abundances of Roseburia, Ruminococcus, Coprococcus, Dorea and Lachnospira genera in weaned piglets compared to prior to weaning showed the quick microbial changes of the piglets' gut microbiota. Downregulation of OCLN, CLDN4, MUC2, MUC13, SLC15A1 and SLC13A1 genes, also evidenced the negative impact of weaning on gut barrier and digestive functions. Metabolomic approach pinpointed significant decreases in choline, LDL, triglycerides, fatty acids, alanine and isoleucine and increases in 3-hydroxybutyrate after weaning. Moreover, the correlation between microbiota and metabolome datasets revealed the existence of metabolic clusters interrelated to different bacterial clusters. Our results demonstrate the impact of weaning stress on the piglet and give insights regarding the associations between gut microbiota and the animal gene activity and metabolic response.


Assuntos
Microbioma Gastrointestinal/genética , Interações entre Hospedeiro e Microrganismos/genética , Animais , Bactérias/genética , Ceco/microbiologia , Fezes/microbiologia , Jejuno/microbiologia , Metaboloma/genética , RNA Ribossômico 16S/genética , Suínos , Desmame
5.
Sci Rep ; 11(1): 6113, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731752

RESUMO

The aim of this study was to determine the possible impact of early socialization and an enriched neonatal environment to improve adaptation of piglets to weaning. We hypothesized that changes in the microbiota colonization process and in their metabolic response and intestinal functionality could help the animals face weaning stress. A total of 48 sows and their litters were allotted into a control (CTR) or an enriched treatment (ENR), in which piglets from two adjacent pens were combined and enriched with toys. The pattern of caecal microbial colonization, the jejunal gene expression, the serum metabolome and the intestinal physiology of the piglets were assessed before (-2 d) and after weaning (+ 3d). A differential ordination of caecal microbiota was observed after weaning. Serum metabolome suggested a reduced energetic metabolism in ENR animals, as evidenced by shifts in triglycerides and fatty acids, VLDL/LDL and creatine regions. The TLR2 gene showed to be downregulated in the jejunum of ENR pigs after weaning. The integration of gene expression, metabolome and microbiota datasets confirmed that differences between barren and enriched neonatal environments were evident only after weaning. Our results suggest that improvements in adaptation to weaning could be mediated by a better response to the post-weaning stress.


Assuntos
Ceco/microbiologia , Microbioma Gastrointestinal , Jejuno , Lactação , Animais , Feminino , Jejuno/metabolismo , Jejuno/microbiologia , Suínos , Desmame
6.
J Neuromuscul Dis ; 8(2): 235-249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33361606

RESUMO

With more widespread prolonged survival, Duchenne muscular dystrophy patients progressively experience multisystem complications. We retrospectively reviewed the charts of 132 Duchenne patients (112 alive/20 dead, age 3.5÷32.3 years) with the aims: 1) to provide a comprehensive description of the clinical status considering different aspects of the disease; 2) to propose a new scoring tool able to consider and pool together heterogeneous different functional. Five functions were analyzed: cardiac, respiratory, nutritional, ambulation and scoliosis. For each function, different items were considered and classified according to clinical severity (as indicated by international guidelines) and an incremental scoring was assigned. In addition, a global score incorporating all functions was defined. The scoring system confirmed that despite the significant protective role of steroids, all functions deteriorated with age. The severity of the global score became significantly higher since the age of 13 years. The severity of cardiac, respiratory and nutritional dysfunction was higher since 18 years. Deceased patients were characterized by significantly worse cardiac function, absence of steroid therapy and later use of respiratory assistive devices. The index proposed in this pilot study is a promising tool able to aggregate and correlate heterogeneous functions. It could become either an individual prognostic indicator of decline or a global score to evaluate changes in clinical trials therefore allowing multicenter studies, optimizing the management of both the primary and the secondary complications of the disease and understanding their relative impact.


Assuntos
Distrofia Muscular de Duchenne/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Itália , Masculino , Projetos Piloto , Estudos Retrospectivos , Centros de Atenção Terciária , Adulto Jovem
7.
Clin Ter ; 171(5): e385-e392, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32901779

RESUMO

BACKGROUND: Marginal bone loss (MBL) represents an important indicator of peri-implant health and the measure of its level is considered a determining factor in the evaluation of the quality of survival. Aim of this study is to compare radiographic changes in the fractal and mesial/distal vertical dimensions of peri-implant trabecular bone of dental implants with a laser-ablated micron-scale modication (LAM) of collar surface after a 5-year follow-up period. MATERIALS AND METHODS: Thirty-four implants with LAM of collar surface (test group = TG) and 31 implants without LAM of collar surface (control group = CG) were placed in 45 non-smoking, periodontally healthy patients. Fractal and vertical dimensions of peri-implant trabecular bone were measured by comparing radiographs taken immediately after prosthesis delivery with those taken 3 years and 5 years after functional loading. RESULT: At the end of the 5-year follow-up, the MBL in the TG was 0.87±0.21 and 0.75±0.25 mm at the mesial and distal aspects, respectively, while a MBL of 2.05±0.25 mm at the mesial aspect and 2.01±0.34 mm at the distal site was recorded in the CG. A statistically significant difference was noted. In the TG the mean fractal dimension before loading was 1.4213±0.0525. It increased significantly to 1.4329±0.0479 at 3 years after loading and remained almost stable at 5 years after loading (1.4327±0.0291). In the CG the mean fractal dimension before loading was 1.4119±0.0414. It increased significantly to 1.4282±0.0324 at 3 years after loading and decreased significantly to 1.4111±0.0624 at 5 years after loading. At the end of the follow-up, differences between both study groups were statistically significant. CONCLUSION: The increased fractal dimension and the reduced MBL around TG implants after 5 years of functional loading indicates a positive effect of a laser-ablated micron-scale modication of collar surface on peri-implant trabecular bone remodeling.


Assuntos
Osso Esponjoso/cirurgia , Implantes Dentários , Terapia a Laser , Adulto , Osso Esponjoso/diagnóstico por imagem , Feminino , Seguimentos , Fractais , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Propriedades de Superfície
8.
Ann Ig ; 32(4): 385-394, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32744297

RESUMO

BACKGROUND: Malnutrition in Intensive Care Unit patients has been associated with worse clinical outcomes such as mortality and length of stay (LOS) in Intensive Care Unit (ICU), and nutritional status of Intensive Care Unit patients in particular seemed to be a significant predictor of mortality. Promptness of clinical nutrition administration is a key of nutritional support whenever volitional intake is unfeasible. Early enteral nutrition is associated with better clinical outcomes (reduced complications, LOS in ICU and in Hospital). The aim of this study is to investigate the nutrition therapy management in a large Academic Hospital, evaluating its effects on mortality and LOS in ICU and in the Hospital. STUDY DESIGN: Data were collected retrospectively from clinical records. Six physicians were trained on the data collection protocol and they reviewed every clinical record of patients included in the survey. METHODS: Data of 426 patients admitted to ICUs between November 2016, 1st and April 2017, 30th were collected. A multivariate logistic adjusted regression, with backward variables selection method, was performed in order to identify predictors of enteral and parenteral nutrition conducted within 48 hours after admission to the ICU. The relation between medical nutrition therapy, mortality and LOS in ICU and in the Hospital were also evaluated. RESULTS: Patients were given prompt parenteral and enteral nutrition in 25.12% and 27.46% of cases, respectively. No association was found between medical nutrition therapy and ICU or hospital mortality. Predictors of early enteral nutrition were type of admission and surgery before admission; early parenteral nutrition predictors were gender, ICU (A vs B), impaired immunity status and Central Venous Catheter presence at admission. CONCLUSIONS: Our study stresses the need of monitoring nutrition prescribing behaviors in acute hospitals in order to better set up tailored interventions to standardize clinicians' practices and to focus on specific training targets.


Assuntos
Nutrição Enteral/métodos , Unidades de Terapia Intensiva , Desnutrição/terapia , Nutrição Parenteral/métodos , Centros Médicos Acadêmicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cuidados Críticos/métodos , Feminino , Mortalidade Hospitalar , Humanos , Itália , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Padrões de Prática Médica/estatística & dados numéricos , Estudos Retrospectivos , Inquéritos e Questionários
10.
Phys Rev E ; 99(3-1): 033004, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30999474

RESUMO

In this work we study the dynamical buckling process of a thin filament immersed in a highly viscous medium. We perform an experimental study to track the shape evolution of the filament during a constant velocity compression. Numerical simulations reproduce the dynamical features observed from the experimental data and allow quantifying the filament's load. We observe that both the filament's load and the wave number evolve in a stepwise manner. In order to achieve a physical insight of the process, we apply a theoretical model to describe the buckling of a filament in a viscous medium. We solve a hydrodynamic equation in terms of normal modes for clamped-clamped boundary conditions and constant applied load. We find a good agreement between experimental data and simulations, suggesting that the proposed mechanistic model captures the essential features underlying the dynamical buckling process.

11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 4431-4435, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946849

RESUMO

Being able to perform a lost movement is an important experience towards increased independence and self-esteem, particularly for neuromuscular patients, who see their muscles weaken day after day. In this pilot study, preliminary results on the testing of a motorized upper-limb exoskeleton for muscular dystrophy patients are presented. The mechatronic system is a five Degrees of Freedom exoskeleton, which acts at shoulder, elbow, and wrist levels. It is designed to help severely impaired people to regain independence during daily-life activities. While wearing the exoskeleton, the user has the direct control of the system by actively piloting the position of end-effector by means of joystick or vocal control. The usability of the system and a quantitative assessment of arm functionality with and without the exoskeleton are evaluated on five muscular dystrophy patients. According to the objective functional benefit evaluation performed through the PUL scale, all participants strongly increased their range of motion and they were able to perform activities that were not possible without the exoskeleton, such as such as feeding, playing activities at the table, combing hair or using a keyboard. As for the evaluation of self-perceived functional benefit, four patients reflected the effective measured functional improvement. System usability has been evaluated to be good.


Assuntos
Exoesqueleto Energizado , Distrofias Musculares , Humanos , Movimento , Distrofias Musculares/reabilitação , Projetos Piloto , Extremidade Superior
12.
Nanomedicine (Lond) ; 13(24): 3091-3106, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30451074

RESUMO

AIM: The aim of this work is the dissection of the molecular pathways underlying the differentiation effect of reduced graphene oxide (GO) materials in the absence of differentiation agents. MATERIALS & METHODS: Reduced GO is obtained either by drop casting method and heat-treated or biological reduction by the interaction between GO and wtPrxI. Cells were grown on both materials and the differentiation process studied by immunological and morphological detection. RESULTS & CONCLUSION: The results obtained indicate that both reduction methods of GO can determine the modulation of pathway involved in mechano-transduction and differentiation, by affecting YAP/TAZ localization outside the nuclei and increasing neuronal differentiation markers. This suggests that the mechano-transduction pathways are responsible for the differentiation process.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Grafite/metabolismo , Mecanotransdução Celular/fisiologia , Neurônios/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Aciltransferases , Diferenciação Celular , Linhagem Celular , Humanos , Neurônios/citologia , Oxirredução , Transdução de Sinais , Propriedades de Superfície , Proteínas de Sinalização YAP
13.
Phys Rev Lett ; 120(19): 196402, 2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29799266

RESUMO

We investigate the 1/3 monolayer α-Pb/Si(111) surface by scanning tunneling spectroscopy (STS) and fully relativistic first-principles calculations. We study both the high-temperature sqrt[3]×sqrt[3] and low-temperature 3×3 reconstructions and show that, in both phases, the spin-orbit interaction leads to an energy splitting as large as 25% of the valence-band bandwidth. Relativistic effects, electronic correlations, and Pb-substrate interaction cooperate to stabilize a correlated low-temperature paramagnetic phase with well-developed lower and upper Hubbard bands coexisting with 3×3 periodicity. By comparing the Fourier transform of STS conductance maps at the Fermi level with calculated quasiparticle interference from nonmagnetic impurities, we demonstrate the occurrence of two large hexagonal Fermi sheets with in-plane spin polarizations and opposite helicities.

14.
Curr Alzheimer Res ; 15(4): 336-344, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28521669

RESUMO

BACKGROUND: PPARs are lipid sensors activated by dietary lipids or their metabolites, mainly fatty acids and eicosanoids, that play critical roles in CNS biology, since brain has a very high lipid content and has the higher energetic metabolism in the body. METHODS: In neurodegenerative diseases in addition to metabolic impairment, also neuroinflammation is observed and PPARs are also closely linked to inflammatory processes. Several studies have revealed a complicated relationship between the innate immune response and tissue metabolism. RESULTS: In the brain, during pathological conditions, an alteration in metabolic status occurs, particularly involving glucose utilization and production, a condition which is generally related to metabolic changes. CONCLUSION: Taking into account the high expression of PPARs in the brain, this review will focus on the role of these transcription factors in CNS diseases.


Assuntos
Encéfalo/metabolismo , Inflamação/metabolismo , Doenças Neurodegenerativas/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Animais , Humanos , Inflamação/patologia
15.
Ciudad Autónoma de Buenos Aires; El presente trabajo de investigación fue realizado con el apoyo de las becas salud investiga a proyectos de investigación 2015 otorgada por el ministerio de salud de la nación, a través de la dirección de investigación en salud.;Si desea acceder al informe completo de esta investigación solicítelo a bvsmsal@gmail.com; 2018. 1 p.
Não convencional em Espanhol | ARGMSAL, BINACIS | ID: biblio-1509289

RESUMO

INTRODUCCIÓN La escala NEWS (National Early Warning Score) clasifica a los pacientes según su probabilidad de deterioro. Fue desarrollada a partir de signos vitales (SV) obtenidos automáticamente. En Argentina, los SV son tomados manualmente; hay una percepción de que no son confiables y su capacidad predictiva es baja. OBJETIVOS Validar la capacidad de discriminación del NEWS a partir de SV, tal como se toman en el medio local. MÉTODOS Nueve hospitales ingresaron pacientes en forma prospectiva, relevando los SV, su hora y fecha, datos demográficos, co-morbilidades, eventos severos y muerte. Se calculó la escala NEWS con cada set de parámetros. Se realizó un análisis de regresión logística evaluando la capacidad del primer valor de NEWS de predecir un evento durante la internación independientemente de la edad, co-morbilidades y sexo. Mediante una curva ROC se analizó la capacidad de discriminación de la media del NEWS y, a través de árboles de decisión, se analizó el mejor valor de corte que predecía muerte y/o evento a las 12 y a las 24 horas. RESULTADOS Ingresaron 1705 pacientes, 869 mujeres, con edad de 18 a 100; 10% de los pacientes presentó algún evento y la mortalidad fue 3,5%. El 90% fue clasificado al ingreso como NEWS de bajo grado de deterioro (0-4), el 5% de riesgo moderado (5-6) y el 5% de riesgo alto (mayor a 7). El valor de NEWS al ingreso de la internación predijo el riesgo de presentar un evento severo durante ella (OR 3,40; IC 2,8-3,5), independientemente de la edad, sexo, y la presencia de co-morbilidades. La escala NEWS fue mejor predictora a las 12 horas previas de un evento que la edad sumada a las co-morbilidades; un valor mayor a 3 fue el predictor más "seguro" de muerte a las 12 horas y a las 24 horas. La media del NEWS durante la internación presentó un área bajo la curva de 0,90 para mortalidad y de 0,80 para evento severo. DISCUSIÓN La escala NEWS es una excelente predictora de la ocurrencia de eventos durante la internación, inclusive a partir de la toma tal como se realiza en este medio.


Assuntos
Sinais Vitais , Pacientes Internados
16.
Nano Lett ; 17(10): 6481-6486, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28872884

RESUMO

Microreactors present innovative solutions for problems pertaining to conventional reactors and therefore have seen successful application in several industrial processes. Yet, its application in heterogeneously catalyzed gas-liquid reactions has been challenging, mainly due to the lack of an easy and flexible methodology for catalyst incorporation inside these reactors. Herein, we report a facile technique for obtaining small (<2 nm) and well-distributed catalytic nanoparticles on the walls of silica-coated capillaries, that act as micro(channel) reactors. These particles are formed in situ on the reactor walls using polyelectrolyte multilayers (PEMs), built by layer-by-layer self-assembly. Manipulating the PEMs' synthesis condition gives easy control over metal loading, without compromising on particle size. Both monometallic (Au and Pd) and bimetallic (AuPd) nanoparticles were successfully obtained using this technique. Finally, these catalytic microreactors were found to exhibit exceptional activity for the direct synthesis of hydrogen peroxide from H2 and O2.

17.
Epidemiol Infect ; 145(14): 2991-2997, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28803563

RESUMO

Salmonella causes an estimated 1·2 million illnesses annually in the USA. Salmonella enterica serotype Javiana (serotype Javiana) is the fourth most common serotype isolated from humans, with the majority of illnesses occurring in southeastern states. The percentage of wetland cover by wetland type and the average incidence rates of serotype Javiana infection in selected counties of the Foodborne Disease Active Surveillance Network (FoodNet) were examined. This analysis explored the relationship between wetland environments and incidence in order to assess whether regional differences in environmental habitats may be associated with observed variations in incidence. Findings suggest that environmental habitats may support reservoirs or contribute to the persistence of serotype Javiana, and may frequently contribute to the transmission of infection compared with other Salmonella serotypes.


Assuntos
Infecções por Salmonella/epidemiologia , Salmonella enterica/fisiologia , Áreas Alagadas , Humanos , Incidência , Infecções por Salmonella/microbiologia , Salmonella enterica/genética , Sorogrupo , Estados Unidos/epidemiologia
18.
Artif Life ; 23(1): 80-104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28140628

RESUMO

Evolutionary robotics using real hardware is currently restricted to evolving robot controllers, but the technology for evolvable morphologies is advancing quickly. Rapid prototyping (3D printing) and automated assembly are the main enablers of robotic systems where robot offspring can be produced based on a blueprint that specifies the morphologies and the controllers of the parents. This article addresses the problem of gait learning in newborn robots whose morphology is unknown in advance. We investigate a reinforcement learning method and conduct simulation experiments using robot morphologies with different size and complexity. We establish that reinforcement learning does the job well and that it outperforms two alternative algorithms. The experiments also give insights into the online dynamics of gait learning and into the influence of the size, shape, and morphological complexity of the modular robots. These insights can potentially be used to predict the viability of modular robotic organisms before they are constructed.


Assuntos
Marcha , Aprendizagem , Robótica/métodos , Algoritmos , Tamanho Corporal , Reforço Psicológico
19.
Cell Cycle ; 16(1): 59-72, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27860527

RESUMO

PPARs are a class of ligand-activated transcription factors belonging to the superfamily of receptors for steroid and thyroid hormones, retinoids and vitamin D that control the expression of a large number of genes involved in lipid and carbohydrate metabolism and in the regulation of cell proliferation, differentiation and death. The role of PPARs in the CNS has been primarily associated with lipid and glucose metabolism; however, these receptors are also implicated in neural cell differentiation and death, as well as neuronal maturation. Although it has been demonstrated that PPARs play important roles in determining NSCs fate, less is known about their function in regulating NSCs metabolism during differentiation. In order to identify the metabolic events, controlled by PPARs, occurring during neuronal precursor differentiation, the glucose and lipid metabolism was followed in a recognized model of neuronal differentiation in vitro, the SH-SY5Y neuroblastoma cell line. Moreover, PPARs distribution were also followed in situ in adult mouse brains. The concept of adult neurogenesis becomes relevant especially in view of those disorders in which a loss of neurons is described, such as Alzheimer disease, Parkinson disease, brain injuries and other neurological disorders. Elucidating the crucial steps in energetic metabolism and the involvement of PPARγ in NSC neuronal fate (lineage) may be useful for the future design of preventive and/or therapeutic interventions.


Assuntos
Envelhecimento/metabolismo , Metabolismo Energético , Neurogênese , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Animais , Padronização Corporal , Compostos de Boro/metabolismo , Encéfalo/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Inativação Gênica , Proteína Glial Fibrilar Ácida/metabolismo , Glicogênio/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Nestina/metabolismo , RNA Interferente Pequeno/metabolismo , beta Catenina/metabolismo
20.
Neuromuscul Disord ; 26(8): 473-80, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27238057

RESUMO

In Duchenne muscular dystrophy (DMD), progressive loss of respiratory function leads to restrictive pulmonary disease and places patients at significant risk for severe respiratory complications. Of particular concern are ineffective cough, secretion retention and recurrent respiratory tract infections. In a Phase 3 randomized controlled study (DMD Long-term Idebenone Study, DELOS) in DMD patients 10-18 years of age and not taking concomitant glucocorticoid steroids, idebenone (900 mg/day) reduced significantly the loss of respiratory function over a 1-year study period. In a post-hoc analysis of DELOS we found that more patients in the placebo group compared to the idebenone group experienced bronchopulmonary adverse events (BAEs): placebo: 17 of 33 patients, 28 events; idebenone: 6 of 31 patients, 7 events. The hazard ratios (HR) calculated "by patient" (HR 0.33, p = 0.0187) and for "all BAEs" (HR 0.28, p = 0.0026) indicated a clear idebenone treatment effect. The overall duration of BAEs was 222 days (placebo) vs. 82 days (idebenone). In addition, there was also a difference in the use of systemic antibiotics utilized for the treatment of BAEs. In the placebo group, 13 patients (39.4%) reported 17 episodes of antibiotic use compared to 7 patients (22.6%) reporting 8 episodes of antibiotic use in the idebenone group. Furthermore, patients in the placebo group used systemic antibiotics for longer (105 days) compared to patients in the idebenone group (65 days). This post-hoc analysis of DELOS indicates that the protective effect of idebenone on respiratory function is associated with a reduced risk of bronchopulmonary complications and a reduced need for systemic antibiotics.


Assuntos
Antioxidantes/uso terapêutico , Distrofia Muscular de Duchenne/complicações , Distrofia Muscular de Duchenne/tratamento farmacológico , Doenças Respiratórias/tratamento farmacológico , Doenças Respiratórias/etiologia , Ubiquinona/análogos & derivados , Adolescente , Antibacterianos/uso terapêutico , Criança , Método Duplo-Cego , Humanos , Incidência , Distrofia Muscular de Duchenne/epidemiologia , Distrofia Muscular de Duchenne/fisiopatologia , Modelos de Riscos Proporcionais , Testes de Função Respiratória , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/fisiopatologia , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/fisiopatologia , Resultado do Tratamento , Ubiquinona/uso terapêutico
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