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1.
Sci Rep ; 12(1): 5152, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35338192

RESUMO

Multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) are two representative chronic inflammatory demyelinating disorders of the central nervous system. We aimed to determine and compare the alterations of white matter (WM) connectivity between MS, NMOSD, and healthy controls (HC). This study included 68 patients with relapsing-remitting MS, 50 with NMOSD, and 26 HC. A network-based statistics method was used to assess disrupted patterns in WM networks. Topological characteristics of the three groups were compared and their associations with clinical parameters were examined. WM network analysis indicated that the MS and NMOSD groups had lower total strength, clustering coefficient, global efficiency, and local efficiency and had longer characteristic path length than HC, but there were no differences between the MS and NMOSD groups. At the nodal level, the MS group had more brain regions with altered network topologies than did the NMOSD group when compared with the HC group. Network alterations were correlated with Expanded Disability Status Scale score and disease duration in both MS and NMOSD groups. Two distinct subnetworks that characterized the disease groups were also identified. When compared with NMOSD, the most discriminative connectivity changes in MS were located between the thalamus, hippocampus, parahippocampal gyrus, amygdala, fusiform gyrus, and inferior and superior temporal gyri. In conclusion, MS patients had greater network dysfunction compared to NMOSD and altered short connections within the thalamus and inferomedial temporal regions were relatively spared in NMOSD compared with MS.


Assuntos
Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Neuromielite Óptica/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla Recidivante-Remitente/patologia , Neuromielite Óptica/patologia , Lobo Temporal/patologia
2.
Sci Rep ; 12(1): 1579, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35091634

RESUMO

Although fatigue is a major symptom in patients with neuromyelitis optica spectrum disorder (NMOSD), the underlying mechanism remains unclear. We explored the relationship between subcortical structures and fatigue severity to identify neural substrates of fatigue in NMOSD. Clinical characteristics with brain magnetic resonance imaging were evaluated in forty patients with NMOSD. Fatigue was assessed using the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-fatigue) questionnaire (a higher score indicates less fatigue). We assessed the correlation between subcortical structures and fatigue severity using surface-based shape analysis. Most of the enrolled patients showed fatigue (72.5%; mean FACIT-fatigue score, 34.8 ± 10.8). The FACIT-fatigue score was negatively correlated with Expanded Disability Status Scale and Beck Depression Inventory scores (r = - 0.382, p = 0.016; r = - 0.578, p < 0.001). We observed that the right thalamus was the only extracted region for various threshold experiments. Further, patients with lower FACIT-fatigue scores (more fatigue) had decreased local shape volume in the right thalamus. Fatigue is common in patients with NMOSD, and atrophy in the right thalamus is strongly correlated with fatigue severity. The local shape volume of the right thalamus might serve as a biomarker of fatigue in NMOSD.


Assuntos
Neuromielite Óptica
3.
Front Immunol ; 12: 677041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394078

RESUMO

Background: Clear associations have been found between vitamin D deficiency and several autoimmune diseases including multiple sclerosis (MS). However, the benefits of vitamin D supplementation on disease management remain a matter of debate. Objective and Methods: Patients with MS (N=12) and neuromyelitis optica spectrum disorder (NMOSD; N=12) were enrolled along with 15 healthy controls. Changes in lymphocyte subset proportions during stimulation of their peripheral blood mononuclear cells (PBMCs) with the active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and correlations with serum concentrations of the vitamin D precursor 25-hydroxyvitamin D3 (serum 25(OH)D3) were explored. The impact of 1,25(OH)2D3 stimulation on the expression of vitamin-D-responsive genes in immune cells was also investigated. Results: In both MS and NMOSD, stimulation of PBMCs with 1,25(OH)2D3 followed by steroid suppressed the proliferation of total lymphocytes and T cells. The ratio of CD19+CD27+ memory B cells (Bmem) to all B cells after stimulation with 1,25(OH)2D3 was negatively correlated with serum 25(OH)D3 in MS (Spearman's ρ=-0.594, p=0.042), but positively correlated in NMOSD (Pearson's r = 0.739, p=0.006). However, there was no relationship between the ratio of Bmem to CD19+CD24+CD38+ regulatory B cells and serum 25(OH)D3 in either MS or NMOSD. In addition, the level of 1,25(OH)2D3-induced CYP24A1 mRNA expression in PBMCs was significantly and negatively correlated with serum 25(OH)D3 (for ΔCT, r=0.744, p=0.014) in MS. Conclusion: These findings suggest a beneficial impact of stimulation of PBMCs with vitamin D followed by steroid on the T-cell population. The association between patient serum 25(OH)D3 and the proportion of Bmem under immune-cell stimulation differed between MS and NMOSD. Further investigations are warranted with larger patient populations.


Assuntos
Linfócitos B/efeitos dos fármacos , Calcifediol/sangue , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Esclerose Múltipla/sangue , Neuromielite Óptica/sangue , Linfócitos T/efeitos dos fármacos , Vitamina D/análogos & derivados , Vitaminas/farmacologia , Adulto , Linfócitos B/imunologia , Estudos de Casos e Controles , Células Cultivadas , Suplementos Nutricionais , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Vitamina D/farmacologia
4.
Front Plant Sci ; 12: 656403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34108979

RESUMO

An electrical conductivity (EC)-based closed-loop soilless culture system is practical for in-field deployment. Literature on the closed-loop soilless culture nutrient management premise the limitations in managing recycled nutrients under dynamic changes in individual nutrient uptake concentrations. However, recent systems analysis studies predicting solutions for nutrient fluctuation stabilization in EC-based closed-loop soilless culture systems suggest that the system may have a deterministic side in nutrient variation. This study aims to derive a nutrient control principle in an EC-based nutrient recycling soilless culture system by theoretical and experimental analyses. An integrated model of solutes such as K+, Ca2+, and Mg2+ and water transport in growing media, automated nutrient solution preparation, and nutrient uptake was designed. In the simulation, the intrinsic characteristics of nutrient changes among open-, semi- closed-, and closed-loop soilless cultures were compared, and stochastic simulations for nutrient control were performed in the closed-loop system. Four automated irrigation modules for comparing nutrient changes among the soilless culture systems were constructed in the greenhouse. Sweet pepper plants were used in the experiment. In the experimental analysis, nutrient concentration conversion to the proportion between nutrients revealed distinctive trends of nutrient changes according to the treatment level of drainage recycling. Theoretical and experimental analyses exhibited that nutrient variations in open-, semi- closed-, and closed-loop soilless culture systems can be integrated as a function of nutrient supply to the system's boundary areas. Furthermore, stochastic simulation analysis indicated that the nutrient ratio in the soilless culture system reveals the nutrient uptake parameter-based deterministic patterns. Thus, the nutrient ratio in the closed-loop soilless culture could be controlled by the long-term feedback of this ratio. We expect that these findings provide theoretical frameworks for systemizing nutrient management techniques in EC-based closed-loop soilless culture systems.

5.
Plant Physiol Biochem ; 162: 388-394, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33740678

RESUMO

Transpiration can directly reflect the response of the crop growth and development, therefore irrigation design based on a transpiration model is an important factor towards establishing an efficient irrigation strategy. Thus, the purpose of this experiment is to develop and verify a tomato transpiration model by correcting the relationship between the transpiration rate and environmental factors by measuring the actual transpiration rate. The actual crop transpiration rate, which is measured using a load cell, and the weight changes calculated at 10-min intervals, are applied to the development of the transpiration model. The experimental results show that the transpiration rate has no linear relationship with the radiation amount (Rad) or vapor pressure deficit (VPD). The relationship between Rad and VPD with transpiration rate was fitted by the exponential rise to maximum, and gaussian peak curve, respectively. This allowed a transpiration model to be developed by compensating the Rad and VPD based on the existing Penman-Monteith (P-M) equation. The developed transpiration model showed higher regression constant values than the existing one. The developed transpiration model from the experiment can be utilized for precise irrigation control.


Assuntos
Transpiração Vegetal , Solanum lycopersicum , Pressão de Vapor , Água
6.
Mult Scler ; 27(6): 964-967, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32779521

RESUMO

We aimed to compare seroprevalence of anti-myelin oligodendrocyte glycoprotein (MOG) and anti-aquaporin-4 (AQP4) antibodies in Korean adults with inflammatory demyelinating diseases (IDDs) of the central nervous system (CNS), based on a multicenter nationwide database. Sera were analyzed using a live cell-based assay for MOG and AQP4 antibodies. Of 586 Korean adults with IDDs of the CNS, 36 (6.1%) and 185 (31.6%) tested positive for MOG and AQP4 antibodies, respectively. No participant showed double positivity. Seroprevalence of MOG antibodies was about five times lower than that of AQP4 antibodies in a large cohort of Korean adults with IDDs of the CNS.


Assuntos
Aquaporina 4 , Doenças do Sistema Nervoso Central , Adulto , Humanos , Glicoproteína Mielina-Oligodendrócito , República da Coreia/epidemiologia , Estudos Soroepidemiológicos
7.
J Phys Ther Sci ; 31(11): 865-868, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31871367

RESUMO

[Purpose] We evaluated the effects of functional electrical stimulation (FES) and an ankle/foot orthosis (AFO) in hemiplegic patients exhibiting excessive plantar flexion during the stance phase, associated with genu recurvatum. [Participants and Methods] In total, 12 stroke patients were recruited. We measured changes in knee and ankle joint angles, gait speed, and step and stride length during the gait cycle during barefoot walking, walking while wearing an AFO, and walking after FES application; we used a three dimensional gait analysis system. [Results] In terms of kinematic variables, FES walking was associated with significant increases in peak ankle dorsiflexion during swing, dorsiflexion angle at initial contact, peak ankle dorsiflexion during stance, knee angle at initial contact, and peak knee flexion in the loading response compared to AFO and barefoot walking. AFO walking was associated with a significant difference in peak ankle dorsiflexion during swing compared to barefoot walking. [Conclusion] FES afforded kinematic advantages to the ankle and knee joints compared to AFO in hemiplegic patients with a genu recurvatum gait.

8.
PLoS One ; 13(10): e0206095, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30339697

RESUMO

OBJECTIVES: To investigate the long-term postoperative outcomes and predictive factors associated with poor surgical outcomes in mesial temporal lobe epilepsy (MTLE). MATERIALS AND METHODS: We enrolled patients with MTLE who underwent resective surgery at single university-affiliated hospital. Surgical outcomes were determined using a modified Engel classification at the 2nd and 5th years after surgery and the last time of follow-up. RESULTS: The mean duration of follow-up after surgery was 7.6 ± 3.7 years (range, 5.0-21.0 years). 334 of 400 patients (83.5%) were seizure-free at the 5th postoperative year. Significant predictive factors of a poor outcome at the 5th year were a history of generalized tonic clonic (GTC) seizures (odds ratio, OR; 2.318), bi-temporal interictal epileptiform discharge (IED) (OR; 3.107), bilateral hippocampal sclerosis (HS) (OR; 5.471), unilateral HS and combined extra-hippocampal lesion (OR; 5.029), and bi-temporal hypometabolism (BTH) (OR; 4.438). Bi-temporal IED (hazard ratio, HR; 2.186), BTH (HR; 2.043), bilateral HS (HR; 2.541) and unilateral HS and combined extra-hippocampal lesion (HR; 2.75) were independently associated with seizure recurrence. We performed a subgroup analysis of 208 patients with unilateral HS, and their independent predictors of a poor outcome at the 5th year were BTH (OR; 5.838) and tailored hippocampal resection (OR; 11.053). CONCLUSION: This study demonstrates that 16.5% of MTLE patients had poor long-term outcomes after surgery. Bilateral involvement in electrophysiological and imaging studies predicts poor surgical outcomes in MTLE patients.


Assuntos
Encéfalo/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idade de Início , Criança , Eletroencefalografia , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Razão de Chances , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Gravação em Vídeo , Adulto Jovem
9.
Cephalalgia ; 38(4): 655-661, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28409524

RESUMO

Objective To determine the natural course of cluster headache. Methods We screened patients with cluster headache who were diagnosed at Samsung Medical Center and lost to follow-up for ≥5 years. Eligible patients were interviewed by phone about the longitudinal changes in headache characteristics and disease course. Remission was defined as symptom-free 1) for longer than twice the longest between-bout period and 2) for ≥5 years. Results Forty-two patients lost to follow-up for mean 7.5 (range, 5.0-15.7) years were included. The length of the last bout did not differ from the first one, while the last between-bout period was longer than the first one ( p = 0.012). Characteristics of cluster headache decreased over time: Side-locked unilaterality (from 92.9% to 78.9%), seasonal and circadian rhythmicity (from 63.9% to 60.9% and from 62.2 to 40.5%, respectively), and autonomic symptoms (from 95.2% to 75.0%). Remission occurred in 14 (33.3%) patients at a mean age of 42.3 (range, 27-65) years, which was not different from the age of last bouts in active patients ( p = 0.623). There was a trend for more seasonal and circadian predilection at baseline in the active group ( p = 0.056 and 0.063, respectively) and fewer lifetime bouts and shorter disease duration in patients in remission ( p = 0.063 and 0.090). Conclusions This study first shows the natural courses of cluster headache. Features of cluster headache become less prominent over time. Remission occurred regardless of age. Although no single predictor of remission was found, our data suggest that remission of cluster headache might not be a consequence of more advanced age, longer duration of disease, or accumulation of lifetime bouts.


Assuntos
Cefaleia Histamínica , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
10.
Front Plant Sci ; 7: 1321, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27667994

RESUMO

Canopy photosynthesis has typically been estimated using mathematical models that have the following assumptions: the light interception inside the canopy exponentially declines with the canopy depth, and the photosynthetic capacity is affected by light interception as a result of acclimation. However, in actual situations, light interception in the canopy is quite heterogenous depending on environmental factors such as the location, microclimate, leaf area index, and canopy architecture. It is important to apply these factors in an analysis. The objective of the current study is to estimate the canopy photosynthesis of paprika (Capsicum annuum L.) with an analysis of by simulating the intercepted irradiation of the canopy using a 3D ray-tracing and photosynthetic capacity in each layer. By inputting the structural data of an actual plant, the 3D architecture of paprika was reconstructed using graphic software (Houdini FX, FX, Canada). The light curves and A/C i curve of each layer were measured to parameterize the Farquhar, von Caemmerer, and Berry (FvCB) model. The difference in photosynthetic capacity within the canopy was observed. With the intercepted irradiation data and photosynthetic parameters of each layer, the values of an entire plant's photosynthesis rate were estimated by integrating the calculated photosynthesis rate at each layer. The estimated photosynthesis rate of an entire plant showed good agreement with the measured plant using a closed chamber for validation. From the results, this method was considered as a reliable tool to predict canopy photosynthesis using light interception, and can be extended to analyze the canopy photosynthesis in actual greenhouse conditions.

11.
Opt Express ; 17(15): 13009-16, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19654705

RESUMO

A photonic crystal microresonator is proposed in this study that is relocatable in two dimensions. A wavelength-scale resonator with high Q-factor (26,000) and high collection efficiency (80%) is formed and repositioned by simply placing and relocating a curved-microfiber to a new position on the surface of a two-dimensional square lattice photonic crystal slab. The formation of the resonator was confirmed by observing lasing of resonators. Infrared microscope images showed that the lasing site is two-dimensionally relocated in-situ. Spectral tuning was demonstrated by modifying the curvature of the microfiber. Functionalities, such as the two-dimensional relocation, spectral tuning and efficient extraction, which the curved-microfiber coupling offers, may provide an alternative way of coupling with a single quantum dot.

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