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1.
ACS Appl Mater Interfaces ; 15(18): 22651-22661, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37115020

RESUMO

Low-power metal oxide (MOX)-based gas sensors are widely applied in edge devices. To reduce power consumption, nanostructured MOX-based sensors that detect gas at low temperatures have been reported. However, the fabrication process of these sensors is difficult for mass production, and these sensors are lack uniformity and reliability. On the other hand, MOX film-based gas sensors have been commercialized but operate at high temperatures and exhibit low sensitivity. Herein, commercially advantageous highly sensitive, film-based indium oxide sensors operating at low temperatures are reported. Ar and O2 gases are simultaneously injected during the sputtering process to form a hydroxy-rich-surface In2O3 film. Conventional indium oxide (In2O3) films (A0) and hydroxy-rich indium oxide films (A1) are compared using several analytical techniques. A1 exhibits a work function of 4.92 eV, larger than that of A0 (4.42 eV). A1 exhibits a Debye length 3.7 times longer than that of A0. A1 is advantageous for gas sensing when using field effect transistors (FETs) and resistors as transducers. Because of the hydroxy groups present on the surface of A1, A1 can react with NO2 gas at a lower temperature (∼100 °C) than A0 (180 °C). Operando diffuse reflectance infrared Fourier transform spectrometry (DRIFTS) shows that NO2 gas is adsorbed to A1 as nitrite (NO2-) at 100 °C and nitrite and nitrate (NO3-) at 200 °C. After NO2 is adsorbed as nitrate, the sensitivity of the A1 sensor decreases and its low-temperature operability is compromised. On the other hand, when NO2 is adsorbed only as nitrite, the performance of the sensor is maintained. The reliable hydroxy-rich FET-type gas sensor shows the best performance compared to that of the existing film-based NO2 gas sensors, with a 2460% response to 500 ppb NO2 gas at a power consumption of 1.03 mW.

2.
Mol Cell Proteomics ; 21(11): 100424, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36220603

RESUMO

Astrocytes are major supportive glia and immune modulators in the brain; they are highly secretory in nature and interact with other cell types via their secreted proteomes. To understand how astrocytes communicate during neuroinflammation, we profiled the secretome of human astrocytes following stimulation with proinflammatory factors. A total of 149 proteins were significantly upregulated in stimulated astrocytes, and a bioinformatics analysis of the astrocyte secretome revealed that the brain renin-angiotensin system (RAS) is an important mechanism of astrocyte communication. We observed that the levels of soluble form of aminopeptidase N (sANPEP), an RAS component that converts angiotensin (Ang) III to Ang IV in a neuroinflammatory milieu, significantly increased in the astrocyte secretome. To elucidate the role of sANPEP and Ang IV in neuroinflammation, we first evaluated the expression of Ang IV receptors in human glial cells because Ang IV mediates biological effects through its receptors. The expression of angiotensin type 1 receptor was considerably upregulated in activated human microglial cells but not in human astrocytes. Moreover, interleukin-1ß release from human microglial cells was synergistically increased by cotreatment with sANPEP and its substrate, Ang III, suggesting the proinflammatory action of Ang IV generated by sANPEP. In a mouse neuroinflammation model, brain microglial activation and proinflammatory cytokine expression levels were increased by intracerebroventricular injection of sANPEP and attenuated by an enzymatic inhibitor and neutralizing antibody against sANPEP. Collectively, our results indicate that astrocytic sANPEP-induced increase in Ang IV exacerbates neuroinflammation by interacting with microglial proinflammatory receptor angiotensin type 1 receptor, highlighting an important role of indirect crosstalk between astrocytes and microglia through the brain RAS in neuroinflammation.


Assuntos
Astrócitos , Microglia , Animais , Camundongos , Humanos , Microglia/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Sistema Renina-Angiotensina , Antígenos CD13/metabolismo , Doenças Neuroinflamatórias , Encéfalo/metabolismo , Modelos Animais de Doenças
3.
J Hazard Mater ; 423(Pt A): 126525, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34246521

RESUMO

A complete hydrodeoxygenation(HDO) of vanillin to yield cycloalkanes was performed using bifunctional Ru loaded HZSM-5 catalysts with different metal loadings (0.1, 0.5, 1, 3, and 5 wt%) and Si/Al2 ratios (Si/Al2 = 23,300) in n-octane/water biphasic system. Both the reaction pathway and product distribution were influenced by the metal/acid balance of the catalysts. Higher metal/acid ratio promoted Caryl-C cleavage reaction, resulting in the increased yield of cyclohexane. Synergetic effect of metal and acid sites was observed in the bifunctional catalyst, attaining as high as 40-fold increase of metal efficiency in the ring hydrogenation reaction, compared to lone metal site catalyst. The effect of solvent composition was evaluated, revealing that the presence of water promoted the overall HDO reaction. By balancing metal/acid and introducing appropriate solvent system, efficient catalytic system that minimized carbon loss and improved metal efficiency for vanillin HDO was obtained.


Assuntos
Óleos de Plantas , Polifenóis , Benzaldeídos , Catálise
5.
Medicina (Kaunas) ; 57(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915966

RESUMO

To date, there is no curable treatment option for non-hereditary degenerative cerebellar ataxia. Here we report the case of a patient with sporadic adult-onset ataxia (SAOA) who underwent allogeneic bone marrow-derived mesenchymal stem cell (MSC) therapy via the intrathecal route. A 60-year-old male patient visited our clinic complaining of progressive gait disturbance that commenced two years ago. Upon neurologic examination, the patient exhibited limb dysmetria and gait ataxia. Brain magnetic resonance imaging (MRI) revealed cerebellar atrophy whereas the autonomic function test was normal. The patient was diagnosed with SAOA. The medications that were initially prescribed had no significant effects on the course of this disease and the symptoms deteriorated progressively. At the age of 64, the patient was treated with allogeneic bone marrow-derived MSC therapy. The subsequent K-SARA (Korean version of the Scale for the Assessment and Rating of Ataxia) scores demonstrated a distinct improvement up until 10 months post-administration. No adverse events were reported. The improved post-treatment K-SARA scores may suggest that the MSC therapy can have a neuroprotective effect and that stem cell therapy may serve as a potential therapeutic option for degenerative cerebellar ataxia.


Assuntos
Ataxia Cerebelar , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Adulto , Medula Óssea , Ataxia Cerebelar/terapia , Humanos , Masculino , Pessoa de Meia-Idade
6.
Front Neurol ; 12: 633393, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33643208

RESUMO

Purpose: Patients with benign paroxysmal positional vertigo (BPPV) experience gait unsteadiness not only during the attacks but also between the spells. This study aimed to measure gait changes in BPPV and determine whether these changes are associated with the involved canal or lesion side. Methods: We recruited 33 patients with a diagnosis of unilateral BPPV. Patients with other vestibular or central nervous system disorders were excluded. Gait was assessed using the GAITRite™ system before and after canalith repositioning treatment (CRT). Results: After CRT, improvements were observed in various gait parameters including velocity (p < 0.001), cadence (p < 0.001), functional ambulation profile (p = 0.011), and the coefficient of variation of stride time (p = 0.004). Exploration of the center of pressure (COP) distribution also revealed improved stabilization during locomotion after CRT. The spatiotemporal gait variables did not differ between the patients with horizontal- and posterior-canal BPPV, or between the ipsilesional and contralesional sides before CRT. Conclusions: The gait parameters reflecting velocity and rhythmicity along with stability of COP distribution improved after the resolution of BPPV. Episodic overexcitation of semicircular canal may impair the vestibular information that is integrated with the other reference afferent systems and lead to impaired gait performance.

7.
Sci Rep ; 11(1): 356, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431916

RESUMO

We employed a hospital-based Internet of Things (IoT) platform to validate the role of real-time activities of daily living (ADL) measurement as a digital biomarker for cognitive impairment in a hospital setting. Observational study. 12 patients with dementia, 11 patients with mild cognitive impairment (MCI), and 15 cognitively normal older adults. The results of 13 experimental ADL tasks were categorized into success or fail. The total number of successful task and the average success proportion of each group was calculated. Time to complete the total tasks was also measured. Patients with dementia, patients with MCI, and cognitively normal older adults performed 13 experimental ADL tasks in a hospital setting. Significant differences in the average success rate of 13 tasks were found among groups. Dementia group showed the lowest success proportion (49.3%) compared with MCI group (78.3%) and normal group (97.4%). Correlation between classical ADL scales and the number of completed ADL tasks was statistically significant. In particular, instrumental ADL (I-ADL) had stronger relationship with the number of completed ADL tasks than Barthel's ADL (B-ADL). Dementia group required more time to accomplish the tasks when compared to MCI and normal groups. This study demonstrated that there is a clear relationship between the performance of experimental ADL tasks and the severity of cognitive impairment. The evaluation of ADLs involving the IoTs platform in an ecological setting allows accurate assessment and quantification of the patient's functional level.


Assuntos
Atividades Cotidianas , Disfunção Cognitiva/psicologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Avaliação Geriátrica , Humanos , Masculino , Projetos Piloto
8.
Sci Rep ; 10(1): 21213, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33273614

RESUMO

We investigated differences in cortical thickness between idiopathic normal-pressure hydrocephalus (INPH) patients and healthy controls. We also explored whether a relationship exists between cortical thinning and gait disturbance in INPH patients. Forty-nine INPH patients and 26 healthy controls were imaged with MRI, including 3-dimensional volumetric images, for automated surface-based cortical thickness analysis across the entire brain. Compared with age- and gender-matched healthy controls, unexpectedly, INPH patients showed statistically significant cortical thickening mainly in areas located in the high convexity of the frontal, parietal, and occipital regions. Additionally, cortical thinning mainly in temporal and orbitofrontal regions was observed in the INPH group relative to the control group. The Gait Status Scale (GSS) scores were negatively correlated with cortical thickness in the medial orbital part of the superior frontal gyrus, gyrus rectus, superior temporal gyrus, temporal pole, and insula. A distinctive pattern of cortical thickness changes was found in INPH patients. We cautiously suggest that cortical thickening in INPH can result from reactive gliosis. Further, our results support the hypothesis that cortical thinning in INPH can result from neuronal degeneration. In addition, cortical thinning can play an important role in gait disturbances in INPH patients.


Assuntos
Córtex Cerebral/patologia , Hidrocefalia de Pressão Normal/patologia , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
9.
Front Neurol ; 11: 392, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508737

RESUMO

Recent studies on Myotonic dystrophy type 1 (DM1) have shown profound impairments in gait, leading to falls. We analyzed functional ambulation profile (FAP) score that reflects the temporal and spatial gait characteristics and investigated correlations with the lower limb muscle magnetic resonance imaging (MRI) and 6 min walk test (6MWT). Twenty patients with DM1 and 20 controls participated in this study. The 6MWT and gait analysis including FAP scores via GAITRite were performed in all patients and controls. DM1 patients displayed slower gait, shorter stride length, shorter stance length, and lower FAP score. Among lower extremity muscles, the gastrocnemius, soleus and tibialis anterior showed the most severe fat infiltration and these crural muscles significantly correlated with FAP and 6MWT. Among crural muscles, tibialis anterior was the most important muscle affecting gait speed, whereas the gastrocnemius contributed substantially to gait instability. FAP score correlated with the muscle imaging and 6MWT in DM1. Therefore, FAP score maybe used as an non-invasive marker that reflects deterioration of gait and a possible surrogate biomarker in DM1.

10.
Headache ; 60(9): 1901-1909, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32463126

RESUMO

OBJECTIVE AND BACKGROUND: Post-dural puncture headache is the most common significant adverse event following lumbar puncture. In this study, we investigated the possible systemic factors associated with risk for post-dural puncture headache (PDPH). METHODS: We performed a retrospective cohort study in 969 patients who underwent diagnostic lumbar puncture following a standardized protocol. We compared the clinical and laboratory profiles of the post-dural puncture headache group and non-headache group. We also identified independent factors associated with the incidence of post-dural puncture headache. RESULTS: A total of 48 patients (5%) reported headache; 12 of these patients (25%) received a therapeutic epidural blood patch and the remaining 36 patients improved with conservative treatment. After adjusting for other variables that could be related to PDPH, we found that the development of post lumbar puncture headache was independently associated with age (OR: 0.97, 95% CI: 0.95-0.99, P = .001) and serum glucose levels (OR: 0.98, 95% CI: 0.97-0.99, P = .008).When the patients were classified by age, serum glucose levels were persistently lower in patients with PDPH vs those patients without PDPH in all age groups, with more clearly significant differences observed in the elderly (age <30 years, 103.4 mg/dL vs 106.3 mg/dL, P = .716; >60 years, 111.8 mg/dL vs 137.3 mg/dL, P = .023). CONCLUSIONS: Low glucose levels were inversely associated with risk for post-dural puncture headache. Patients with low serum glucose should be carefully monitored for headache after lumbar puncture.


Assuntos
Glicemia , Placa de Sangue Epidural , Cefaleia Pós-Punção Dural/diagnóstico , Cefaleia Pós-Punção Dural/terapia , Sistema de Registros , Adulto , Fatores Etários , Idoso , Placa de Sangue Epidural/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cefaleia Pós-Punção Dural/epidemiologia , Estudos Prospectivos , Risco
11.
J Vestib Res ; 30(1): 17-23, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31796719

RESUMO

Accumulating evidences show that the vestibular system contributes to cognitive function, including visuospatial ability, memory, and attention. Conversely, cognitive processes appear to affect the vestibular system. Based on the assumption that cognitive impairment correlates to increased perception of dizziness, we recruited 308 adults with cognitive decline from neurodegenerative disorders and administered neuropsychological tests and the Dizziness Handicap Inventory. Global cognitive measures did not correlate with increased dizziness, whereas attentional and visuospatial cognitive ability was correlated with scores of the Dizziness Handicap Inventory. Furthermore, patients with both cognitive impairment and postural instability experienced notably worse dizziness than those without postural instability, suggesting that postural instability is an important determinant of dizziness.


Assuntos
Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Tontura/diagnóstico , Tontura/epidemiologia , Testes Neuropsicológicos , Testes de Função Vestibular/métodos , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/fisiopatologia , Tontura/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural/fisiologia
12.
Sci Rep ; 9(1): 16255, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700018

RESUMO

We investigated gait performance utilizing a quantitative gait analysis for 2 groups: (1) idiopathic normal-pressure hydrocephalus (INPH) patients who had a positive response to the cerebrospinal fluid tap test (CSFTT) and (2) healthy controls. The aims of the study were (1) to analyze the characteristics of gait features, (2) to characterize changes in gait parameters before and after the CSFTT, and (3) to determine whether there was any relationship between stride time and stride length variability and Frontal Assessment Battery (FAB) scores in INPH patients. Twenty-three INPH patients and 17 healthy controls were included in this study. Compared with healthy controls, the gait of INPH patients was characterized by lower velocity, shorter stride length, and more broad-based gait. Patients with INPH had a longer stance phase with increased double-limb support. Variability in stride time and stride length was increased in INPH patients. Stride time and stride length variability were correlated with FAB score. After the CSFTT, gait velocity, stride length, and step width significantly improved. There were significant decreases in stride time and stride length variability. These results suggest that the CSFTT for INPH patients might improve the so-called balance-related gait parameter (ie, step width) as well. Stride time and stride length variability also responded to the CSFTT. Association between FAB scores and both stride time and stride length variability suggests involvement of similar circuits producing gait variability and frontal lobe functions in INPH patients.


Assuntos
Biomarcadores , Análise da Marcha , Marcha , Hidrocefalia de Pressão Normal/líquido cefalorraquidiano , Hidrocefalia de Pressão Normal/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Diagnóstico Diferencial , Gerenciamento Clínico , Suscetibilidade a Doenças , Feminino , Humanos , Hidrocefalia de Pressão Normal/etiologia , Masculino , Prognóstico
13.
Front Neurol ; 9: 433, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29930534

RESUMO

Patients with vestibular migraine are susceptible to motion sickness. This study aimed to determine whether the severity of posture instability is related to the susceptibility to motion sickness. We used a visual motion paradigm with two conditions of the stimulated retinal field and the head posture to quantify postural stability while maintaining a static stance in 18 patients with vestibular migraine and in 13 age-matched healthy subjects. Three parameters of postural stability showed differences between VM patients and controls: RMS velocity (0.34 ± 0.02 cm/s vs. 0.28 ± 0.02 cm/s), RMS acceleration (8.94 ± 0.74 cm/s2 vs. 6.69 ± 0.87 cm/s2), and sway area (1.77 ± 0.22 cm2 vs. 1.04 ± 0.25 cm2). Patients with vestibular migraine showed marked postural instability of the head and neck when visual stimuli were presented in the retinal periphery. The pseudo-Coriolis effect induced by head roll tilt was not responsible for the main differences in postural instability between patients and controls. Patients with vestibular migraine showed a higher visual dependency and low stability of the postural control system when maintaining quiet standing, which may be related to susceptibility to motion sickness.

14.
Comput Methods Biomech Biomed Engin ; 20(6): 653-662, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28349767

RESUMO

Due to the recent increase in the number of stent insertion procedures, the number of studies to evaluate the mechanical behaviors of stents, such as the stress and deformation states, using finite element analysis is also increasing. However, it is still not easy to design stents that are uniformly expanded and show enough radial strength and flexibility. Therefore, in this study, the Taguchi method and finite element analysis were used to determine a set of optimal design variables for unit patterns of stents, and a new design approach was developed to realize uniform expansion, enough radial strength and good flexibility. The stent designed using the new design approach was verified by experiments.


Assuntos
Análise de Elementos Finitos , Desenho de Prótese , Stents , Ligas/farmacologia , Humanos , Imageamento Tridimensional , Lasers , Estresse Mecânico
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