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1.
ACS Nano ; 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32401016

RESUMO

Conventional melanoma therapies suffer from the toxicity and side effects of repeated treatments due to the aggressive and recurrent nature of melanoma cells. Less-invasive topical chemotherapies by utilizing polymeric microneedles have emerged as an alternative, but the sustained, long-lasting release of drug cargos remains challenging. In addition, the size of the microneedles is relatively bulky for the small, curvilinear, and exceptionally sensitive cornea for the treatment of ocular melanoma. Here, we report a design of bioresorbable, miniaturized porous-silicon (p-Si) needles with covalently linked drug cargos at doses comparable to those of conventional polymeric microneedles. The p-Si needles are built on a water-soluble film as a temporary flexible holder that can be intimately interfaced with the irregular surface of living tissues, followed by complete dissolution with saline solution within 1 min. Consequently, the p-Si needles remain embedded inside tissues and then undergo gradual degradation, allowing for sustained release of the drug cargos. Its utility in unobtrusive topical delivery of chemotherapy with minimal side effects is demonstrated in a murine melanoma model.

2.
Neuroimage ; : 116899, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32380138

RESUMO

Prior studies have shown that patients suffering from chronic Low Back Pain (cLBP) have impaired somatosensory processing including reduced tactile acuity, i.e. reduced ability to resolve fine spatial details with the perception of touch. The central mechanism(s) underlying reduced tactile acuity are unknown but may include changes in specific brain circuitries (e.g. neuroplasticity in primary somatosensory cortex, S1). Furthermore, little is known about the linkage between changes in tactile acuity and the amelioration of cLBP by somatically-directed therapeutic interventions, such as acupuncture. In this longitudinal neuroimaging study, we evaluated healthy control adults (HC, N=50) and a large sample of cLBP patients (N=102) with structural brain imaging (T1-weighted MRI for Voxel Based Morphometry, VBM; Diffusion Tensor Imaging, DTI) and tactile acuity testing using two-point discrimination threshold (2PDT) over the lower back (site of pain) and finger (control) locations. Patients were evaluated at baseline and following a 4-week course of acupuncture, with patients randomized to either verum acupuncture, two different forms of sham acupuncture (designed with or without somatosensory afference), or no-intervention usual care control. At baseline, cLBP patients demonstrated reduced acuity (greater 2PDT, P=0.01) over the low back, but not finger (P=0.29) locations compared to HC, suggesting that chronic pain affects tactile acuity specifically at body regions encoding the experience of clinical pain. At baseline, Gray Matter Volume (GMV) was elevated and Fractional Anisotropy (FA) was reduced, respectively, in the S1-back region of cLBP patients compared to controls (P<0.05). GMV in cLBP correlated with greater 2PDT-back scores (ρ=0.27, P=0.02). Following verum acupuncture, tactile acuity over the back was improved (reduced 2PDT) and greater improvements were associated with reduced S1-back GMV (ρ=0.52, P=0.03) and increased S1-back adjacent white matter FA (ρ=-0.56, P=0.01). These associations were not seen for non-verum control interventions. Thus, S1 neuroplasticity in cLBP is linked with deficits in tactile acuity and, following acupuncture therapy, may represent early mechanistic changes in somatosensory processing that track with improved tactile acuity.

3.
J Am Chem Soc ; 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32267155

RESUMO

The singlet fission (SF) process is generally defined as the conversion of one singlet exciton (S1) into two triplet excitons (2·T1), which has the potential to overcome thermalization losses in the field of photovoltaic devices. Among the applicable compounds for SF-based photovoltaic devices, perylene bisimide (PBI) is one of the best candidates because of its electronic tunability and photostability. However, the strategy for efficient SF in PBIs remains ambiguous because of numerous competing relaxation pathways in PBI-based molecular materials. In this regard, for the first time, we observed the SF mechanism in PBI dimers by controlling the intrinsic factor (exciton coupling) and the external environment (solvent polarity and viscosity). Time-resolved spectroscopic measurements and quantum chemical simulations reveal that efficient SF occurs through the charge-transfer-assisted mechanism, entailing a large structural fluctuation. Our findings not only highlight the SF mechanism in PBI dimers but also suggest the factors responsible for an efficient SF process, which are important considerations in the design of molecular materials for photovoltaic devices.

4.
J Am Chem Soc ; 142(18): 8074-8079, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32294387

RESUMO

We developed a new optical method to determine the rate of reverse intersystem crossing (krISC) in thermally activated delayed fluorescent (TADF) organic chromophores using time-resolved transient absorption spectroscopy. We successfully correlated the krISC of the TADF-chromophores with device performance. Specifically, we focused on the external quantum efficiency (ηEQE) and the stability of the device at high brightness levels. It is believed that by obtaining a large krISC one may reduce the possibility of triplet-triplet annihilation (TTA) and increase the long-term stability of organic light emitting diodes (OLEDs) devices at high brightness levels (ηEQE roll-off). In this contribution, we investigate the photophysical mechanism in a series of TADF-chromophores based on carbazole or acridine derivatives as donor moieties, and triazine or benzonitrile derivatives as the acceptor moieties. We found a relationship between large krISC values and high ηEQE values at low operating voltages for the TADF-chromophores investigated. In addition, those chromophores with a larger krISC illustrated a smaller ηEQE roll-off (higher stability) at high operating voltages. These features are beneficial for superior OLEDs performing devices. Contrarily, we found that if a chromophore has a krISC ≤ 105s-1 its ηEQE is ≤5%. Such a small krISC suggests that there is no TADF effect operating in these organic systems and the molecule is not efficient in harvesting triplet excitons. Emission lifetime-based methodologies for determining the krISC were included for comparison but failed to predict the devices performance of the investigated TADF-chromophores to the same extent of our proposed methodology.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32345005

RESUMO

Manganese-based spinel cathode materials for sodium-ion batteries (SIBs) are promising candidates for next-generation batteries; especially, Na[Ni0.5Mn1.5]O4 (NNMO) should get attention because of its relatively high operating voltage and firm octahedral host structure. Here, first-principles calculations and the phase field method are used to elucidate the reasons for the low performance of NNMO compared with Li[Ni0.5Mn1.5]O4, and we determine the requirements for realizing high-performance cathode materials for SIBs. Owing to the Ni2+/Ni4+ double redox, NNMO could operate at a high voltage; however, the large Na+ increases the local site energy of the redox center, promoting electron extraction from the redox center, leading to unexpected voltage loss. Additionally, the homogeneous free energy confirms that NNMO would undergo phase separation into fully intercalated and deintercalated phases, inducing lattice misfits along the interfaces of the two phases. Particularly, a higher phase transition barrier and large Na+ cause fast phase separation, inducing increased polarization and severe stress field upon cycling. The present analysis with comprehensive first-principles calculations and the phase field method provides three critical factors toward high electrochemical performance: (i) strengthening Ni-O bonding to avoid undesirable voltage loss, (ii) increasing the vacancy/Na solubility during (de)sodiation to enhance cyclability, and (iii) suppressing the structural distortion during (de)sodiation to prevent mechanical failure. Based on these crucial points, additionally, we suggest the M-pillared Na1-xMx[Ni0.5Mn1.5]O4 (monovalent or divalent species, M), where the M works to strengthen the redox center for improved energy density and to alleviate the drastic structural change and voltage hysteresis for better cyclability, would have superior electrochemical performance as a cathode material for SIBs.

6.
Neurobiol Aging ; 90: 93-98, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32169355

RESUMO

Partitioning-defective 1 (PAR-1), a conserved cell polarity regulator, plays an important role in synaptic development, and its mutation affects the formation of synaptic boutons and localization of postsynaptic density protein Discs large (Dlg) at the neuromuscular junction (NMJ) in Drosophila. Drosophila PAR-1 and its human homolog, Microtubule affinity-regulating kinases (MARK), are also known to be implicated in Alzheimer's disease (AD) by controlling tau-mediated Aß toxicity. However, the molecular mechanisms of PAR-1 function remain incompletely understood. Here we identified Pod-1, an actin-microtubule crosslinker, which functionally and physically interacts with PAR-1 in Drosophila. Pod-1 prominently co-localizes with PAR-1 in the postsynaptic region and regulates PAR-1 activity at the NMJ. Synaptic defects, including the reduction of boutons and delocalization of Dlg caused by PAR-1 overexpression, were rescued by Pod-1 knockdown. Conversely, the reduction of synaptic boutons in PAR-1 overexpressed NMJ was synergistically enhanced by the overexpression of Pod-1. Furthermore, Pod-1 increases the PAR-1 dependent S262 phosphorylation of tau, which is known to contribute to tau-mediated Aß toxicity. In line with the change of tau phosphorylation, Pod-1 knockdown rescued tau-mediated synaptic toxicity at the NMJ. Our results suggest that Pod-1 may act as a modulator of PAR-1 in synaptic development and tau-mediated toxicity.

7.
ACS Nano ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31967453

RESUMO

We introduce the synthesis of hybrid nanostructures comprised of ZnO nanocrystals (NCs) decorating nanosheets and nanowires (NWs) of MoS2 prepared by atomic layer deposition (ALD). The concentration, size, and surface-to-volume ratio of the ZnO NCs can be systematically engineered by controlling both the number of ZnO ALD cycles and the properties of the MoS2 substrates, which are prepared by sulfurizing ALD MoO3. Analysis of the chemical composition combined with electron microscopy and synchrotron X-ray techniques as a function of the number of ZnO ALD cycles, together with the results of quantum chemical calculations, help elucidate the ZnO growth mechanism and its dependence on the properties of the MoS2 substrate. The defect density and grain size of MoS2 nanosheets are controlled by the sulfurization temperature of ALD MoO3, and the ZnO NCs in turn nucleate selectively at defect sites on MoS2 surface and enlarge with increasing ALD cycle numbers. At higher ALD cycle numbers, the coalescence of ZnO NCs contributes to an increase in areal coverage and NC size. Additionally, the geometry of the hybrid structures can be tuned by changing the dimensionality of the MoS2, by employing vertical NWs of MoS2 as the substrate for ALD ZnO NCs, which leads to improvement of the relevant surface-to-volume ratio. Such materials are expected to find use in newly expanded applications, especially those such as sensors or photodevices based on a p-n heterojunction which relies on coupling transition-metal dichalcogenides with NCs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31939649

RESUMO

Although they have attracted enormous attention in recent years, software-based and two-dimensional hardware-based artificial neural networks (ANNs) may consume a great deal of power. Because there will be numerous data transmissions through a long interconnection for learning, power consumption in the interconnect will be an inevitable problem for low-power computing. Therefore, we suggest and report 3D stackable synaptic transistors for 3D ANNs, which would be the strongest candidate in future computing systems by minimizing power consumption in the interconnection. To overcome the problems of enormous power consumption, it might be necessary to introduce a 3D stackable ANN platform. With this structure, short vertical interconnection can be realized between the top and bottom devices, and the integration density can be significantly increased for integrating numerous neuromorphic devices. In this paper, we suggest and show the feasibility of monolithic 3D integration of synaptic devices using the channel layer transfer method through a wafer bonding technique. Using a low-temperature processible III-V and composite oxide (Al2O3/HfO2/Al2O3)-based weight storage layer, we successfully demonstrated synaptic transistors showing good linearity (αp/αd = 1.8/0.5), a high transconductance ratio (6300), and very good stability. High learning accuracy of 97% was obtained in the training of 1 million MNIST images based on the device characteristics.

9.
ACS Nano ; 14(1): 676-687, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31927973

RESUMO

Fine-tuning of the surface free energy (SFE) of a solid material facilitates its use in a wide range of applications requiring precise control of the ubiquitous presence of liquid on the surface. In this study, we found that the SFE of rare-earth oxide (REO) thin films deposited by atomic layer deposition (ALD) gradually decreased with increasing film thickness; however, these changes could not be understood by classical interaction models. Herein, the mechanism underlying the aforesaid decrease was systematically studied by measuring contact angles, surface potential, adhesion force, crystalline structures, chemical compositions, and morphologies of the REO films. A growth mode of the REO films was observed: layer-by-layer growth at the initial stage with an amorphous phase and subsequent crystalline island growth, accompanied by a change in the crystalline structure and orientation that affects the SFE. The portion of the surface crystalline facets terminated with (222) and (440) planes evolved with an increase in ALD cycles and film thickness, as an amorphous phase was transformed. Based on this information, we demonstrated an SFE-tuned liquid tweezer with selectivity to target liquid droplets. We believe that the results of this fundamental and practical study, with excellent selectivity to liquids, will have significant impacts on coating technology.

10.
J Am Chem Soc ; 142(5): 2346-2354, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31920085

RESUMO

Materials design increasingly relies on first-principles calculations for screening important candidates and for understanding quantum mechanisms. Density functional theory (DFT) is by far the most popular first-principles approach due to its efficiency and accuracy. However, to accurately predict structures and thermodynamics, DFT must be paired with a van der Waals (vdW) dispersion correction. Therefore, such corrections have been the subject of intense scrutiny in recent years. Despite significant successes in organic molecules, no existing model can adequately cover the full range of common materials, from metals to ionic solids, hampering the applications of DFT for modern problems such as battery design. Here, we introduce a universally optimized vdW-corrected DFT method that demonstrates an unbiased reliability for predicting molecular, layered, ionic, metallic, and hybrid materials without incurring a large computational overhead. We use our method to accurately predict the intercalation potentials of layered electrode materials of a Li-ion battery system, a problem for which the existing state-of-the-art methods fail. Thus, we envisage broad use of our method in the design of chemo-physical processes of new materials.

11.
Proc Natl Acad Sci U S A ; 117(2): 1216-1222, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31889001

RESUMO

Certain long-distance migratory animals, such as salmon and sea turtles, are thought to imprint on the magnetic field of their natal area and to use this information to help them return as adults. Despite a growing body of indirect support for such imprinting, direct experimental evidence thereof remains elusive. Here, using the fruit fly as a magnetoreceptive model organism, we demonstrate that exposure to a specific geographic magnetic field during a critical period of early development affected responses to a matching magnetic field gradient later in life. Specifically, hungry flies that had imprinted on a specific magnetic field from 1 of 3 widely separated geographic locations responded to the imprinted field, but not other magnetic fields, by moving downward, a geotactic behavior associated with foraging. This same behavior occurred spontaneously in the progeny of the next generation: female progeny moved downward in response to the field on which their parents had imprinted, whereas male progeny did so only in the presence of these females. These results represent experimental evidence that organisms can learn and remember a magnetic field to which they were exposed during a critical period of development. Although the function of the behavior is not known, one possibility is that imprinting on the magnetic field of a natal area assists flies and their offspring in recognizing locations likely to be favorable for foraging and reproduction.


Assuntos
Migração Animal/fisiologia , Drosophila/fisiologia , Campos Magnéticos , Animais , Feminino , Comportamento de Retorno ao Território Vital/fisiologia , Fixação Psicológica Instintiva/fisiologia , Masculino , Reprodução
12.
J Pharm Sci ; 109(4): 1615-1622, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31945310

RESUMO

Despite being a major breakthrough in multiple myeloma therapy, carfilzomib (CFZ, a second-generation proteasome inhibitor drug) has been largely ineffective against solid cancer, possibly due to its pharmacokinetic drawbacks including metabolic instability. Recently, quinic acid (QA, a low-affinity ligand of selectins upregulated in peritumoral vasculature) was successfully utilized as a surface modifier for nanoparticles containing paclitaxel. Here, we designed QA-conjugated nanoparticles containing CFZ (CFZ@QANP; the surface of poly(lactic-co-glycolic acid) nanoparticles modified by conjugation with a QA derivative). Compared to the clinically used cyclodextrin-based formulation (CFZ-CD), CFZ@QANP enhanced the metabolic stability and in vivo exposure of CFZ in mice. CFZ@QANP, however, showed little improvement in suppressing tumor growth over CFZ-CD against the murine 4T1 orthotopic breast cancer model. CFZ@QANP yielded no enhancement in proteasomal inhibition in excised tumors despite having a higher level of remaining CFZ than CFZ-CD. These results likely arise from delayed, incomplete CFZ release from CFZ@QANP as observed using biorelevant media in vitro. These results suggest that the applicability of QANP may not be predicted by physicochemical parameters commonly used for formulation design. Our current results highlight the importance of considering drug release kinetics in designing effective CFZ formulations for solid cancer therapy.

13.
ACS Nano ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31999424

RESUMO

Atomically dispersed precious metal catalysts have emerged as a frontier in catalysis. However, a robust, generic synthetic strategy toward atomically dispersed catalysts is still lacking, which has limited systematic studies revealing their general catalytic trends distinct from those of conventional nanoparticle (NP)-based catalysts. Herein, we report a general synthetic strategy toward atomically dispersed precious metal catalysts, which consists of "trapping" precious metal precursors on a heteroatom-doped carbonaceous layer coated on a carbon support and "immobilizing" them with a SiO2 layer during thermal activation. Through the "trapping-and-immobilizing" method, five atomically dispersed precious metal catalysts (Os, Ru, Rh, Ir, and Pt) could be obtained and served as model catalysts for unravelling catalytic trends for the oxygen reduction reaction (ORR). Owing to their isolated geometry, the atomically dispersed precious metal catalysts generally showed higher selectivity for H2O2 production than their NP counterparts for the ORR. Among the atomically dispersed catalysts, the H2O2 selectivity was changed by the types of metals, with atomically dispersed Pt catalyst showing the highest selectivity. A combination of experimental results and density functional theory calculations revealed that the selectivity trend of atomically dispersed catalysts could be correlated to the binding energy difference between *OOH and *O species. In terms of 2 e- ORR activity, the atomically dispersed Rh catalyst showed the best activity. Our general approach to atomically dispersed precious metal catalysts may help in understanding their unique catalytic behaviors for the ORR.

14.
J Am Chem Soc ; 142(5): 2087-2092, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31951390

RESUMO

We describe a new electrophotocatalytic strategy that harnesses the power of light and electricity to generate an excited radical anion with a reducing potential of -3.2 V vs SCE, which can be used to activate substrates with very high reduction potentials (Ered ≈ -1.9 to -2.9 V). The resultant aryl radicals can be engaged in various synthetically useful transformations to furnish arylboronate, arylstannane, and biaryl products.

15.
Nano Lett ; 20(1): 95-100, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31752490

RESUMO

Identifying material parameters affecting properties of ferromagnets is key to optimized materials that are better suited for spintronics. Magnetic anisotropy is of particular importance in van der Waals magnets, since it not only influences magnetic and spin transport properties, but also is essential to stabilizing magnetic order in the two-dimensional limit. Here, we report that hole doping effectively modulates the magnetic anisotropy of a van der Waals ferromagnet and explore the physical origin of this effect. Fe3-xGeTe2 nanoflakes show a significant suppression of the magnetic anisotropy with hole doping. Electronic structure measurements and calculations reveal that the chemical potential shift associated with hole doping is responsible for the reduced magnetic anisotropy by decreasing the energy gain from the spin-orbit induced band splitting. Our findings provide an understanding of the intricate connection between electronic structures and magnetic properties in two-dimensional magnets and propose a method to engineer magnetic properties through doping.

16.
Br J Pharmacol ; 177(3): 668-686, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31658360

RESUMO

BACKGROUND AND PURPOSE: We recently reported that AAV1-Rheb(S16H) transduction could protect hippocampal neurons through the induction of brain-derived neurotrophic factor (BDNF) in the rat hippocampus in vivo. It is still unclear how neuronal BDNF produced by AAV1-Rheb(S16H) transduction induces neuroprotective effects in the hippocampus and whether its up-regulation contributes to the enhance of a neuroprotective system in the adult brain. EXPERIMENTAL APPROACH: To determine the presence of a neuroprotective system in the hippocampus of patients with Alzheimer's disease (AD), we examined the levels of glial fibrillary acidic protein, BDNF and ciliary neurotrophic factor (CNTF) and their receptors, tropomyocin receptor kinase B (TrkB) and CNTF receptor α(CNTFRα), in the hippocampus of AD patients. We also determined whether AAV1-Rheb(S16H) transduction stimulates astroglial activation and whether reactive astrocytes contribute to neuroprotection in models of hippocampal neurotoxicity in vivo and in vitro. KEY RESULTS: AD patients may have a potential neuroprotective system, demonstrated by increased levels of full-length TrkB and CNTFRα in the hippocampus. Further AAV1-Rheb(S16H) transduction induced sustained increases in the levels of full-length TrkB and CNTFRα in reactive astrocytes and hippocampal neurons. Moreover, neuronal BDNF produced by Rheb(S16H) transduction of hippocampal neurons induced reactive astrocytes, resulting in CNTF production through the activation of astrocytic TrkB and the up-regulation of neuronal BDNF and astrocytic CNTF which had synergistic effects on the survival of hippocampal neurons in vivo. CONCLUSIONS AND IMPLICATIONS: The results demonstrated that Rheb(S16H) transduction of hippocampal neurons could strengthen the neuroprotective system and this intensified system may have a therapeutic value against neurodegeneration in the adult brain.

17.
J Phys Condens Matter ; 32(3): 035801, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31491781

RESUMO

We study the magnetocrystalline anisotropy (MCA) energy of Fe16-n X n N2 ([Formula: see text]), where X = Ti, V, Cr, Mn, Co, Ni, Cu. To understand the microscopic origin and basic mechanism controlling the MCA energy of Fe16-n X n N2, we first examined the behavior of the MCA energy of Fe16N2, focusing on the spin-orbit coupling (SOC), and compared the behavior with other alloy systems (FeCo, FePt and CoPt) with L10 structure. We find that whereas the MCA energy of FeCo is determined by the spin-conserved terms of the SOC energy, the MCA energy of Fe16N2 is determined by mutual competition between spin-conserved and spin-flip terms. We then studied the effect of the transition element X on the phase stability and MCA of Fe16-n X n N2. The MCA energy and cohesive energy are calculated to determine the most stable configuration for each choice of X and n, and compared with those of Fe16N2. For X = V and Cu, both the MCA and phase stability improved noticeably. For X = Co, the MCA energy improves, but Fe16-n Co n N2 is less stable than Fe16N2. The microscopic mechanism underlying the MCA energy enhancement due to X = V, Cu and Co in Fe16-n X n N2 was studied by examining the data for spin- and site-resolved projected density of states (PDOS), as well as each spin-conserved and spin-flip terms contributing to the SOC energy.

18.
Int J Mol Sci ; 21(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861806

RESUMO

Developmentally regulated GTP-binding protein 2 (DRG2) was first identified in the central nervous system of mice. However, the physiological function of DRG2 in the brain remains largely unknown. Here, we demonstrated that knocking out DRG2 impairs the function of dopamine neurons in mice. DRG2 was strongly expressed in the neurons of the dopaminergic system such as those in the striatum (Str), ventral tegmental area (VTA), and substantia nigra (SN), and on neuronal cell bodies in high-density regions such as the hippocampus (HIP), cerebellum, and cerebral cortex in the mouse brain. DRG2 knockout (KO) mice displayed defects in motor function in motor coordination and rotarod tests and increased anxiety. However, unexpectedly, DRG2 depletion did not affect the dopamine (DA) neuron population in the SN, Str, or VTA region or dopamine synthesis in the Str region. We further demonstrated that dopamine release was significantly diminished in the Str region of DRG2 KO mice and that treatment of DRG2 KO mice with l-3,4-dihydroxyphenylalanine (L-DOPA), a dopamine precursor, rescued the behavioral motor deficiency in DRG2 KO mice as observed with the rotarod test. This is the first report to identify DRG2 as a key regulator of dopamine release from dopamine neurons in the mouse brain.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Proteínas de Ligação ao GTP/genética , Transtornos Motores/genética , Animais , Ansiedade/genética , Ansiedade/metabolismo , Corpo Estriado/citologia , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Proteínas de Ligação ao GTP/análise , Proteínas de Ligação ao GTP/metabolismo , Deleção de Genes , Camundongos , Camundongos Knockout , Transtornos Motores/metabolismo
19.
J Exerc Rehabil ; 15(5): 657-662, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31723553

RESUMO

The objectives of this study were to compare the differences in physical performance of elite male collegiate soccer players according to the Functional Movement Screen (FMS) total scores and to investigate the association between the FMS total score and physical performance. A total of 20 elite male collegiate soccer players (mean age, 19.6±0.7 years; height, 173.4±4.4 cm; body weight, 66.9±7.3 kg; and body mass index, 22.0±2.0 kg/m2) participated in the present study. The subjects were divided into two groups: the high FMS (FMS total score ≥14 points, n=10) and low FMS (FMS total score <14 points, n=10). All participants completed 10-m and 30-m sprint tests, the arrowhead agility test (right and left), and a coordination test. The statistical methods used to verify the study results were the independent sample t-test and Kendall's Tau b correlation test. There were significant differences between the high and low FMS groups in the 10-m (P=0.014) and 30-m sprint (P=0.002) and arrowhead agility tests (right, P=0.039). Conversely, there were no significant differences in the arrowhead agility (left) and coordination tests between the two groups (P>0.05). Moreover, the FMS total score was found to have significant negative correlations with the 10-m sprint (r=-0.444, P=0.017), 30-m sprint (r=-0.425, P=0.016), and arrowhead agility tests (right, r=-0.389, P=0.023). These results suggest that higher FMS total scores could have a positive effect on the physical performance of the players.

20.
PLoS One ; 14(11): e0225229, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31725773

RESUMO

BACKGROUND: Although scoring and machine learning methods have been developed to predict patient deterioration, bedside assessment by nurses should not be overlooked. This study aimed to evaluate the performance of subjective bedside assessment of the patient by the rapid response team (RRT) nurses in predicting short-term patient deterioration. METHODS: Patients noticed by RRT nurses based on the vital sign instability, abnormal laboratory results, and direct contact via phone between November 1, 2016, and December 12, 2017, were included. Five RRT nurses visited the patients according to their shifts and assessed the possibility of patient deterioration. Patient acuity rating (PAR), a scale of 1-7, was used as the tool of bedside assessment. Other scores, including the modified early warning score, VitalPAC early warning score, standardised early warning score, and cardiac arrest risk triage, were calculated afterwards. The performance of these scores in predicting mortality and/or intensive care unit admission within 1 day was compared by calculating the area under the receiver operating curve. RESULTS: A total of 1,426 patients were included in the study, of which 258 (18.1%) died or were admitted to the intensive care unit within 1 day. The area under the receiver operating curve of PAR was 0.87 (95% confidence interval [CI] 0.84-0.89), which was higher than those of modified early warning score (0.66, 95% CI 0.62-0.70), VitalPAC early warning score (0.69, 95% CI 0.66-0.73), standardised early warning score (0.67, 95% CI 0.63-0.70) and cardiac arrest risk triage (0.63, 95% CI 0.59-0.66) (P<0.001). CONCLUSIONS: PAR assessed by RRT nurses can be a useful tool for assessing short-term patient prognosis in the RRT setting.

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