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1.
Nano Lett ; 23(3): 916-924, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36651830

RESUMEN

Gibberellins (GAs) are a class of phytohormones, important for plant growth, and very difficult to distinguish because of their similarity in chemical structures. Herein, we develop the first nanosensors for GAs by designing and engineering polymer-wrapped single-walled carbon nanotubes (SWNTs) with unique corona phases that selectively bind to bioactive GAs, GA3 and GA4, triggering near-infrared (NIR) fluorescence intensity changes. Using a new coupled Raman/NIR fluorimeter that enables self-referencing of nanosensor NIR fluorescence with its Raman G-band, we demonstrated detection of cellular GA in Arabidopsis, lettuce, and basil roots. The nanosensors reported increased endogenous GA levels in transgenic Arabidopsis mutants that overexpress GA and in emerging lateral roots. Our approach allows rapid spatiotemporal detection of GA across species. The reversible sensor captured the decreasing GA levels in salt-treated lettuce roots, which correlated remarkably with fresh weight changes. This work demonstrates the potential for nanosensors to solve longstanding problems in plant biotechnology.


Asunto(s)
Arabidopsis , Nanotubos de Carbono , Giberelinas/química , Giberelinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Arabidopsis/metabolismo , Nanotubos de Carbono/química , Fluorescencia , Colorantes
2.
Proc Natl Acad Sci U S A ; 117(43): 26616-26625, 2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-33055208

RESUMEN

Molecular recognition binding sites that specifically identify a target molecule are essential for life science research, clinical diagnoses, and therapeutic development. Corona phase molecular recognition is a technique introduced to generate synthetic recognition at the surface of a nanoparticle corona, but it remains an important question whether such entities can achieve the specificity of natural enzymes and receptors. In this work, we generate and screen a library of 24 amphiphilic polymers, preselected for molecular recognition and based on functional monomers including methacrylic acid, acrylic acid, and styrene, iterating upon a poly(methacrylic acid-co-styrene) motif. When complexed to a single-walled carbon nanotube, some of the resulting corona phases demonstrate binding specificity remarkably similar to that of phosphodiesterase type 5 (PDE5), an enzyme that catalyzes the hydrolysis of secondary messenger. The corona phase binds selectively to a PDE5 inhibitor, Vardenafil, as well as its molecular variant, but not to other potential off-target inhibitors. Our work herein examines the specificity and sensitivity of polymer "mutations" to the corona phase, as well as direct competitions with the native binding PDE5. Using structure perturbation, corona surface characterization, and molecular dynamics simulations, we show that the molecular recognition is associated with the unique three-dimensional configuration of the corona phase formed at the nanotube surface. This work conclusively shows that corona phase molecular recognition can mimic key aspects of biological recognition sites and drug targets, opening up possibilities for pharmaceutical and biological applications.


Asunto(s)
Materiales Biomiméticos , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5 , Nanotubos de Carbono/química , Sitios de Unión , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/química , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/metabolismo , Simulación de Dinámica Molecular , Diclorhidrato de Vardenafil/química , Diclorhidrato de Vardenafil/metabolismo
3.
Int J Mol Sci ; 24(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37958901

RESUMEN

Activation of mammalian target of rapamycin (mTOR) has been known as one of the contributing factors in nociceptive sensitization after peripheral injury. Its activation followed by the phosphorylation of downstream effectors causes hyperexcitability of primary sensory neurons in the dorsal root ganglion. We investigated whether a single injection of rAAV-shmTOR would effectively downregulate both complexes of mTOR in the long-term and glial activation as well. Male SD rats were categorized into shmTOR (n = 29), shCON (n = 23), SNI (n = 13), and Normal (n = 8) groups. Treatment groups were injected with rAAV-shmTOR or rAAV-shCON, respectively. DRG tissues and sciatic nerve were harvested for Western blot and immunohistochemical analyses. Peripheral sensitization was gradually attenuated in the shmTOR group, and it reached a peak on PID 21. Western blot analysis showed that both p-mTORC1 and p-mTORC2 were downregulated in the DRG compared to shCON and SNI groups. We also found decreased expression of phosphorylated p38 and microglial activation in the DRG. We first attempted a therapeutic strategy for neuropathic pain with a low dose of AAV injection by interfering with the mTOR signaling pathway, suggesting its potential application in pain treatment.


Asunto(s)
Neuralgia , Traumatismos del Sistema Nervioso , Ratas , Masculino , Animales , Hiperalgesia/etiología , Hiperalgesia/metabolismo , Ratas Sprague-Dawley , Neuralgia/etiología , Neuralgia/terapia , Neuralgia/metabolismo , Nervio Ciático/metabolismo , Traumatismos del Sistema Nervioso/metabolismo , Sirolimus , Serina-Treonina Quinasas TOR/metabolismo , Ganglios Espinales/metabolismo , Mamíferos
4.
Psychol Med ; 52(11): 2189-2197, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35193713

RESUMEN

BACKGROUND: The two key mechanisms affected by internet gaming disorder (IGD) are cognitive and reward processing. Despite their significance, little is known about neurophysiological features as determined using resting-state electroencephalography (EEG) source functional connectivity (FC). METHODS: We compared resting-state EEG source FC within the default mode network (DMN) and reward/salience network (RSN) between patients with IGD and healthy controls (HCs) to identify neurophysiological markers associated with cognitive and reward processing. A total of 158 young male adults (79 patients with IGD and 79 HCs) were included, and the source FC of the DMN and RSN in five spectral bands (delta, theta, alpha, beta, and gamma) were assessed. RESULTS: Patients with IGD showed increased theta, alpha, and beta connectivity within the DMN between the orbitofrontal cortex and parietal regions compared with HCs. In terms of RSN, patients with IGD exhibited elevated alpha and beta connectivity between the anterior cingulate gyrus and temporal regions compared with HCs. Furthermore, patients with IGD showed negative correlations between the severity of IGD symptoms and/or weekly gaming time and theta and alpha connectivity within the DMN and theta, alpha, and beta connectivity within the RSN. However, the duration of IGD was not associated with EEG source FC. CONCLUSIONS: Hyper-connectivities within the DMN and RSN may be considered potential state markers associated with symptom severity and gaming time in IGD.


Asunto(s)
Conducta Adictiva , Mapeo Encefálico , Adulto , Humanos , Masculino , Vías Nerviosas/diagnóstico por imagen , Trastorno de Adicción a Internet/diagnóstico por imagen , Encéfalo , Imagen por Resonancia Magnética , Electroencefalografía , Recompensa , Internet
5.
Sensors (Basel) ; 22(2)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35062462

RESUMEN

Spinal cord stimulation is a therapy to treat the severe neuropathic pain by suppressing the pain signal via electrical stimulation of the spinal cord. The conventional metal packaged and battery-operated implantable pulse generator (IPG) produces electrical pulses to stimulate the spinal cord. Despite its stable operation after implantation, the implantation site is limited due to its bulky size and heavy weight. Wireless communications including wireless power charging is also restricted, which is mainly attributed to the electromagnetic shielding of the metal package. To overcome these limitations, here, we developed a fully implantable miniaturized spinal cord stimulator based on a biocompatible liquid crystal polymer (LCP). The fabrication of electrode arrays in the LCP substrate and monolithically encapsulating the circuitries using LCP packaging reduces the weight (0.4 g) and the size (the width, length, and thickness are 25.3, 9.3, and 1.9 mm, respectively). An inductive link was utilized to wirelessly transfer the power and the data to implanted circuitries to generate the stimulus pulse. Prior to implantation of the device, operation of the pulse generator was evaluated, and characteristics of stimulation electrode such as an electrochemical impedance spectroscopy (EIS) were measured. The LCP-based spinal cord stimulator was implanted into the spared nerve injury rat model. The degree of pain suppression upon spinal cord stimulation was assessed via the Von Frey test where the mechanical stimulation threshold was evaluated by monitoring the paw withdrawal responses. With no spinal cord stimulation, the mechanical stimulation threshold was observed as 1.47 ± 0.623 g, whereas the stimulation threshold was increased to 12.7 ± 4.00 g after spinal cord stimulation, confirming the efficacy of pain suppression via electrical stimulation of the spinal cord. This LCP-based spinal cord stimulator opens new avenues for the development of a miniaturized but still effective spinal cord stimulator.


Asunto(s)
Terapia por Estimulación Eléctrica , Estimulación de la Médula Espinal , Animales , Electrodos Implantados , Dolor , Polímeros , Ratas , Médula Espinal
6.
Small ; 17(31): e2100540, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34176216

RESUMEN

Vitamins such as riboflavin and ascorbic acid are frequently utilized in a range of biomedical applications as drug delivery targets, fluidic tracers, and pharmaceutical excipients. Sensing these biochemicals in the human body has the potential to significantly advance medical research and clinical applications. In this work, a nanosensor platform consisting of single-walled carbon nanotubes (SWCNTs) with nanoparticle corona phases engineered to allow for the selective molecular recognition of ascorbic acid and riboflavin, is developed. The study provides a methodological framework for the implementation of colloidal SWCNT nanosensors in an intraperitoneal SKH1-E murine model by addressing complications arising from tissue absorption and scattering, mechanical perturbations, as well as sensor diffusion and interactions with the biological environment. Nanosensors are encapsulated in a polyethylene glycol diacrylate hydrogel and a diffusion model is utilized to validate analyte transport and sensor responses to local concentrations at the boundary. Results are found to be reproducible and stable after exposure to 10% mouse serum even after three days of in vivo implantation. A geometrical encoding scheme is used to reference sensor pairs, correcting for in vivo optical and mechanical artifacts, resulting in an order of magnitude improvement of p-value from 0.084 to 0.003 during analyte sensing.


Asunto(s)
Nanopartículas , Nanotubos de Carbono , Animales , Colorantes , Ratones , Vitaminas
7.
Cereb Cortex ; 30(9): 4914-4921, 2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32377680

RESUMEN

The ability to detect and correct errors is a critical aspect of human cognition. Neuronal dysfunction in error processing has been reported in addictive disorders. The aim of this study was to investigate neural systems underlying error processing using event-related potentials (ERPs) and current source localization as well as neurocognitive executive function tests in patients with Internet gaming disorder (IGD). A total of 68 individuals (34 patients with IGD and 34 healthy controls [HCs]) were included, and two ERP components, error-related negativity (ERN) and error positivity (Pe), were extracted during a GoNogo task. Patients with IGD exhibited significantly reduced ERN and Pe amplitudes compared with HCs. Standardized low-resolution brain electromagnetic tomography (sLORETA) in between-group comparisons revealed that patients with IGD had decreased source activations of the Pe component in the anterior cingulate cortex (ACC) under the Nogo condition. These ERP changes were associated with deficits in decision-making and response inhibition in IGD patients. The results suggest that IGD may be associated with functional abnormalities in the ACC and alterations in neural activity related to both the early unconscious and the later conscious stages of error processing, as well as deficits in area of decision-making.


Asunto(s)
Giro del Cíngulo/fisiopatología , Trastorno de Adicción a Internet/fisiopatología , Adolescente , Adulto , Mapeo Encefálico , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiología , Adulto Joven
8.
Addict Biol ; 25(4): e12805, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31297935

RESUMEN

Heart rate variability (HRV) can be used to represent the regulatory adaptive system and is a proxy for neurovisceral integration. Consistent with the view that, like other addictions, Internet gaming disorder (IGD) involves disrupted regulatory function, the present study hypothesized that IGD patients would show (a) decreased HRV, (b) ineffective functional neural connectivity, and (c) differential patterns of association between HRV and functional neural connectivity relative to healthy controls (HCs). The present study included 111 young adults (53 IGD patients and 58 age- and sex-matched HCs) who underwent simultaneous recordings with an electrocardiogram and electroencephalogram during a resting state. Heart rate (HR), HRV, and functional neural connectivity were calculated using the graph theory approach. Compared with the HCs, the IGD patients exhibited elevated HR and decreased HRV based on the high frequency (HF), which reflects suppression of parasympathetic and/or vagal tone. The IGD patients also exhibited a heightened theta band characteristic path length (CPL) compared with HCs, indicating decreased efficacy of the functional network. Furthermore, IGD patients exhibited negative correlations between the standard deviation of the normal-to-normal interval index (SDNNi) and theta and delta CPL values, which were not observed in HCs. In conclusion, the present findings suggest that IGD patients might have maladaptive brain-body integration features involving disruptions of the autonomic nervous system and brain function.


Asunto(s)
Encéfalo/fisiopatología , Frecuencia Cardíaca/fisiología , Trastorno de Adicción a Internet/fisiopatología , Sistema Nervioso Parasimpático/fisiopatología , Adulto , Estudios de Casos y Controles , Electrocardiografía , Electroencefalografía , Femenino , Humanos , Masculino , Vías Nerviosas/fisiología , Ritmo Teta/fisiología , Adulto Joven
9.
Neurosurg Focus ; 49(1): E11, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32610286

RESUMEN

OBJECTIVE: Artificial manipulation of animal movement could offer interesting advantages and potential applications using the animal's inherited superior sensation and mobility. Although several behavior control models have been introduced, they generally epitomize virtual reward-based training models. In this model, rats are trained multiple times so they can recall the relationship between cues and rewards. It is well known that activation of one side of the nigrostriatal pathway (NSP) in the rat induces immediate turning toward the contralateral side. However, this NSP stimulation-induced directional movement has not been used for the purpose of animal-robot navigation. In this study, the authors aimed to electrically stimulate the NSP of conscious rats to build a command-prompt rat robot. METHODS: Repetitive NSP stimulation at 1-second intervals was applied via implanted electrodes to induce immediate contraversive turning movements in 7 rats in open field tests in the absence of any sensory cues or rewards. The rats were manipulated to navigate from the start arm to a target zone in either the left or right arm of a T-maze. A leftward trial was followed by a rightward trial, and each rat completed a total of 10 trials. In the control group, 7 rats were tested in the same way without NSP stimulation. The time taken to navigate the maze was compared between experimental and control groups. RESULTS: All rats in the experimental group successfully reached the target area for all 70 trials in a short period of time with a short interstimulus interval (< 0.7 seconds), but only 41% of rats in the control group reached the target area and required a longer period of time to do so. The experimental group made correct directional turning movements at the intersection zone of the T-maze, taking significantly less time than the control group. No significant difference in navigation duration for the forward movements on the start and goal arms was observed between the two groups. However, the experimental group showed quick and accurate movement at the intersection zone, which made the difference in the success rate and elapsed time of tasks. CONCLUSIONS: The results of this study clearly indicate that a rat-robot model based on NSP stimulation can be a practical alternative to previously reported models controlled by virtual sensory cues and rewards.


Asunto(s)
Conducta Animal/fisiología , Estimulación Eléctrica , Electrodos Implantados , Robótica , Animales , Encéfalo/fisiología , Estimulación Eléctrica/métodos , Masculino , Ratas Sprague-Dawley
10.
Nano Lett ; 19(11): 7712-7724, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31565943

RESUMEN

The corona phase-the adsorbed layer of polymer, surfactant, or stabilizer molecules around a nanoparticle-is typically utilized to disperse nanoparticles into a solution or solid phase. However, this phase also controls molecular access to the nanoparticle surface, a property important for catalytic activity and sensor applications. Unfortunately, few methods can directly probe the structure of this corona phase, which is subcategorized as either a hard, immobile corona or a soft, transient corona in exchange with components in the bulk solution. In this work, we introduce a molecular probe adsorption (MPA) method for measuring the accessible nanoparticle surface area using a titration of a quenchable fluorescent molecule. For example, riboflavin is utilized to measure the surface area of gold nanoparticle standards, as well as corona phases on dispersed single-walled carbon nanotubes and graphene sheets. A material balance on the titration yields certain surface coverage parameters, including the ratio of the surface area to dissociation constant of the fluorophore, q/KD, as well as KD itself. Uncertainty, precision, and the correlation of these parameters across different experimental systems, preparations, and modalities are all discussed. Using MPA across a series of corona phases, we find that the Gibbs free energy of probe binding scales inversely with the cube root of surface area, q. In this way, MPA is the only technique to date capable of discerning critical structure-property relationships for such nanoparticle surface phases. Hence, MPA is a rapid quantitative technique that should prove useful for elucidating corona structure for nanoparticles across different systems.


Asunto(s)
Nanopartículas/química , Nanotubos de Carbono/química , Corona de Proteínas/análisis , Adsorción , Colorantes Fluorescentes/análisis , Oro/química , Grafito/química , Nanoestructuras/química , Riboflavina/análisis , Espectrometría de Fluorescencia/métodos , Propiedades de Superficie
11.
Small ; 15(37): e1901468, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31338962

RESUMEN

Colloidal dispersions of nanomaterials are often polydisperse in size, significantly complicating their characterization. This is particularly true for materials early in their historical development due to synthetic control, dispersion efficiency, and instability during storage. Because a wide range of system properties and technological applications depend on particle dimensions, it remains an important problem in nanotechnology to identify a method for the routine characterization of polydispersity in nanoparticle samples, especially changes over time. Commonly employed methods such as dynamic light scattering or analytical ultracentrifugation (AUC) accurately estimate only the first moment of the distribution or are not routine. In this work, the use of single-particle tracking (SPT) to probe size distributions of common nanoparticle dispersions, including polystyrene nanoparticles, single-walled carbon nanotubes, graphene oxide, chitosan-tripolyphosphate, acrylate, hexagonal boron nitride, and poly(lactic-co-glycolic acid), is proposed and explored. The analysis of particle tracks is conducted using a newly developed Bayesian algorithm that is called Maximum A posteriori Nanoparticle Tracking Analysis. By combining SPT and AUC techniques, it is shown that it is possible to independently estimate the mean aspect ratio of anisotropic particles, an important characterization property. It is concluded that SPT provides a facile, rapid analytical method for routine nanomaterials characterization.


Asunto(s)
Nanopartículas/química , Nanotubos de Carbono/química , Algoritmos , Teorema de Bayes , Compuestos de Boro/química , Quitosano/química , Grafito/química , Tamaño de la Partícula , Polifosfatos/química , Poliestirenos/química
12.
J Clin Psychopharmacol ; 38(3): 243-246, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29601316

RESUMEN

BACKGROUND: Some glutamatergic modulators have demonstrated rapid and relatively sustained antidepressant properties in patients with major depressive disorder. Because the potassium channel activator diazoxide increases glutamate uptake via potassium channel activation, we hypothesized that it might exert antidepressant effects by increasing the removal of glutamate from the synaptic cleft, thereby reducing excessive glutamate transmission. METHODS: This randomized, double-blind, placebo-controlled, crossover, single-site inpatient clinical study was conducted at the National Institute of Mental Health to assess the efficacy and safety of a 3-week course of diazoxide (200-400 mg daily, twice a day) versus a 3-week course of placebo in 6 participants with treatment-refractory major depressive disorder. The primary clinical outcome measure was change in Montgomery-Asberg Depression Rating Scale score from baseline to posttreatment. Quantitative insulin sensitivity check index, as well as concomitant imaging measures (electroencephalography, proton magnetic resonance spectroscopy, magnetoencephalography), were used as potential surrogate markers of target (KATP channel) engagement. RESULTS: The study was halted due to severe adverse effects. Given the small sample size, statistical evaluation of the effect of diazoxide on Montgomery-Asberg Depression Rating Scale scores or the imaging measures was not pursued. Visual inspection of the quantitative insulin sensitivity check index test revealed no evidence of target engagement. CONCLUSIONS: Although the results are negative, they are an important addition to the literature in this rapidly changing field.


Asunto(s)
Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Resistente al Tratamiento/tratamiento farmacológico , Diazóxido/administración & dosificación , Canales de Potasio/efectos de los fármacos , Adulto , Anciano , Estudios Cruzados , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Resistente al Tratamiento/fisiopatología , Diazóxido/efectos adversos , Diazóxido/farmacología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Terminación Anticipada de los Ensayos Clínicos , Femenino , Ácido Glutámico/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Canales de Potasio/metabolismo , Escalas de Valoración Psiquiátrica , Resultado del Tratamiento
14.
BMC Geriatr ; 16: 1, 2016 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-26729190

RESUMEN

BACKGROUND: Despite their strong increase, the population of the very old, including near-centenarians and centenarians, represent an unstudied and underserved population. Available studies mostly concentrate on predictors of exceptional longevity, but rarely extend their focus to other areas of functioning. Also, little is known about what contributes to experiencing a quality life in very old age. The present population-based study aims at providing a comprehensive picture of key domain of functioning, including physical, cognitive, social and mental function in very old individuals and to determine predictors of mental health indicators. METHODS: A total of 119 individuals aged 95 to 107 living in private dwellings and residential care facilities were recruited based on the New York City Voters Registry. Participants answered questions regarding their health and activities of daily living. Their cognitive functioning was determined using the Mini-Mental State Examination and the Global Deterioration Scale. Social resources were measured with number of children and the Lubben Scale. Mental health was assessed with the Geriatric Depression Scale and the Satisfaction with Life Scale. RESULTS: An unexpectedly large proportion of the sample lived in the community. On average, cognitive functioning was high. Although five diseases were reported on average, participants reported good health. Functional status was reduced. Most participants had at least one person for communication/social support. On average, depression was below cut-off, and most participants reported high life satisfaction. Regression analyses indicated that individual differences in depression were associated with subjective health, IADL and relatives support. For life satisfaction, subjective health, ADL and number of children were most important. Demographic characteristics, number of illnesses or cognitive status were not significant. CONCLUSIONS: Despite reduced levels of physical functioning and social resources, very old participants were in good mental health suggesting high resilience and ability to adapt to age-associated challenges. That a large proportion of them lived in the community further highlights their desire for leading an autonomous life, which may have been facilitated by New York service culture. More research is necessary to provide guidance for the development of well-suited services for this very old population.


Asunto(s)
Actividades Cotidianas , Envejecimiento , Cognición , Calidad de Vida , Anciano de 80 o más Años , Envejecimiento/fisiología , Envejecimiento/psicología , Depresión/diagnóstico , Depresión/epidemiología , Femenino , Evaluación Geriátrica/métodos , Humanos , Vida Independiente/estadística & datos numéricos , Masculino , Competencia Mental , Salud Mental/estadística & datos numéricos , Pruebas Neuropsicológicas , Ciudad de Nueva York/epidemiología , Escalas de Valoración Psiquiátrica , Habilidades Sociales , Apoyo Social
15.
J Aging Soc Policy ; 28(3): 165-86, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26959657

RESUMEN

This paper provides a detailed picture of the sources and types of informal support available to centenarians, depending on their housing and care arrangements. Participants were 112 centenarians and 96 primary contacts of centenarians enrolled in the population-based Second Heidelberg Centenarian Study. Findings indicate that children of centenarians were their primary source of support in daily life. Those without living children had overall less help. Most frequently reported was help with administrative tasks, regardless of centenarians' residence or living arrangement. All other types of help (e.g., with activities of daily living and housework) were reported by about one-third and were mostly provided by children; centenarians without children were more likely to have friends/neighbors involved in some of these tasks. The one category reported by a third of the centenarians regardless of residence, living arrangements, or presence of a child was help with socializing/companionship. Findings constitute an important step toward identifying and meeting the support needs of centenarians and their families. Policy implications are discussed.


Asunto(s)
Actividades Cotidianas , Familia , Apoyo Social , Anciano de 80 o más Años , Femenino , Alemania , Humanos , Entrevistas como Asunto , Masculino , Características de la Residencia , Factores Socioeconómicos , Encuestas y Cuestionarios
16.
J Am Chem Soc ; 136(49): 17213-23, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25386672

RESUMEN

We introduce a general and versatile methodology that allows a facile incorporation of the functional components with completely different chemistry of hydrophilic/hydrophobic properties within nanocomposite films, and furthermore combine a number of the distinctive advantages of traditional electrostatic layer-by-layer (LbL) assembly in aqueous media and covalent LbL assembly in nonpolar media. Our approach, amphiphilic LbL assembly, is based on the high affinity between sulfonic (or phosphonic) acid-functionalized materials in aqueous media and hydrophobic metal oxide (or metal) NPs stabilized by oleic acid (OA) in nonpolar solvent. For demonstrating the effectiveness of our approach, we show that amphiphilic LbL assembly can be easily applied to the preparation of functional colloid materials allowing the reversible phase transfer between aqueous and nonpolar media, and supercapacitor electrodes with high volumetric capacitance (280 F·cm(-3) at 10 mV·s(-1)) using reduced graphene oxide with sulfonic acid moieties and well-defined OA-Fe3O4 NPs.

17.
Animals (Basel) ; 14(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38473203

RESUMEN

Cultured meat production relies on various cell types, including muscle stem cells (MuSCs), embryonic stem cell lines, induced pluripotent cell lines, and naturally immortalized cell lines. MuSCs possess superior muscle differentiation capabilities compared to the other three cell lines, making them key for cultured meat development. Therefore, to produce cultured meat using MuSCs, they must first be effectively separated from muscles. At present, the methods used to isolate MuSCs from muscles include (1) the pre-plating method, using the ability of cells to adhere differently, which is a biological characteristic of MuSCs; (2) the density gradient centrifugation method, using the intrinsic density difference of cells, which is a physical characteristic of MuSCs; and (3) fluorescence- and magnetic-activated cell sorting methods, using the surface marker protein on the cell surface of MuSCs, which is a molecular characteristic of MuSCs. Further efficient and valuable methods for separating MuSCs are expected to be required as the cell-based cultured meat industry develops. Thus, we take a closer look at the four methods currently in use and discuss future development directions in this review.

18.
Pain ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38422490

RESUMEN

ABSTRACT: Neuropathic pain is a type of chronic pain that entails severe prolonged sensory dysfunctions caused by a lesion of the somatosensory system. Many of those suffering from the condition do not experience significant improvement with existing medications, resulting in various side effects. In this study, Sprague-Dawley male rats were used, and long-term deep brain stimulation of the ventrolateral periaqueductal gray was conducted in a rat model of spared nerve injury. We found that 5-Hz deep brain stimulation effectively modulated mechanical allodynia and induced neuronal activation in the rostral ventromedial medulla, restoring impaired descending serotonergic system. At the spinal level, glial cells were still activated but only the 5-HT1a receptor in the spinal cord was activated, implying its inhibitory role in mechanical allodynia. This study found that peripheral neuropathy caused dysfunction in the descending serotonergic system, and prolonged stimulation of ventrolateral periaqueductal gray can modulate the pathway in an efficient manner. This work would provide new opportunities for the development of targeted and effective treatments for this debilitating disease, possibly giving us lower chances of side effects from repeated high-frequency stimulation or long-term use of medication.

19.
Cell Death Discov ; 10(1): 144, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491062

RESUMEN

Particulate matter (PM) is a global environmental hazard, which affects human health through free radical production, cell death induction, and immune responses. PM activates inflammasomes leading to excessive inflammatory responses and induces ferroptosis, a type of cell death. Despite ongoing research on the correlation among PM-induced ferroptosis, immune response, and inflammasomes, the underlying mechanism of this relationship has not been elucidated. In this study, we demonstrated the levels of PM-induced cell death and immune responses in murine macrophages, J774A.1 and RAW264.7, depending on the size and composition of particulate matter. PM2.5, with extraction ions, induced significant levels of cell death and immune responses; it induces lipid peroxidation, iron accumulation, and reactive oxygen species (ROS) production, which characterize ferroptosis. In addition, inflammasome-mediated cell death occurred owing to the excessive activation of inflammatory responses. PM-induced iron accumulation activates ferroptosis and inflammasome formation through ROS production; similar results were observed in vivo. These results suggest that the link between ferroptosis and inflammasome formation induced by PM, especially PM2.5 with extraction ions, is established through the iron-ROS axis. Moreover, this study can effectively facilitate the development of a new therapeutic strategy for PM-induced immune and respiratory diseases.

20.
Foods ; 13(4)2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38397540

RESUMEN

Ecklonia cava, a brown seaweed native to the East Asian coast, is known for its unique composition, including polysaccharides, polyphenols, and phlorotannins. Fucoidan is a sulfated polysaccharide widely used as a functional ingredient in foods. This study obtained crude polysaccharides (ECC_CPS) from E. cava celluclast enzymatic hydrolysate using ethanol precipitation. ECC_CPS increased cell viability during the proliferation of Hanwoo muscle satellite cells (HMSCs). The effect of ECC_CPS on the expression of proliferation-related markers was confirmed as MYF5 and MYOD expression significantly increased, whereas PAX7 expression was maintained. The evaluation of cell migration activity has a major impact on cell proliferation and differentiation, and the cell migration index significantly increased with ECC_CPS treatment (p < 0.01). This was related to the HGF/MET pathway and FAK pathway. Treatment with ECC_CPS promoted differentiation at the cell differentiation stage, thereby increasing the expression of differentiation markers, such as MYH2, MYH7, and MYOG (p < 0.001 or p < 0.01). Therefore, our findings imply that crude polysaccharide obtained from E. cava can be an additive ingredient that enhances the proliferation and differentiation of muscle satellite cells used in the manufacture of cultured meat products.

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