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1.
BMC Geriatr ; 23(1): 847, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-38093200

RESUMO

BACKGROUND: Cognitive impairment, a characteristic and prior stage of dementia, is a serious public health concern in Korea a country with rapidly aging population. In a neurovisceral integration model, cognitive ability is connected to emotional and autonomic regulation via an interconnection in the brain, which may be associated with health-related quality of life (HRQoL). METHODS: This study investigated the association between the HRQoL and the autonomic nervous system (ANS) via EuroQoL-5 Dimension (EQ-5D) and heart rate variability (HRV) among 417 patients who visited the Neurology Department in Veterans Health Service Medical Center, Seoul, South Korea. RESULTS: The mean age of 275 patients in the cognitive impairment group (CIG) was higher than that of 142 patients in the normal cognition group (NCG) (74.85 years vs. 72.96 years, p < 0.001). In a generalized linear model with a beta coefficient (ß), an increase in HRQoL was associated with higher HRV levels was observed only in CIG (CIG: the standard deviation of all NN intervals (SDNN) (ln, ms): ß = 0.02, p = 0.007; Total power spectral density (TP) (ln, ms2): ß = 0.01, p = 0.007; High frequency (HF) (ln, ms2): ß = 0.01, p = 0.015; Low frequency (LF) (ln, ms2): ß = 0.01, p = 0.003) (NCG: SDNN (ln, ms): ß = 0.01, p = 0.214; TP (ln, ms2): ß = 0.01, p = 0.144; HF (ln, ms2): ß = 0.00, p = 0.249; LF (ln, ms2): ß = 0.01, p = 0.294). CONCLUSIONS: We found a significant association between HRQoL and HRV in Korean elders with cognitive impairment. However, this study is cross-sectional, so we cannot define direct causation. Further studies are needed to support our findings and to elucidate the biological mechanisms underlying these associations, especially in people cognitively impaired.


Assuntos
Disfunção Cognitiva , Qualidade de Vida , Humanos , Idoso , Estudos Transversais , Frequência Cardíaca/fisiologia , República da Coreia/epidemiologia , Disfunção Cognitiva/diagnóstico
2.
JMIR Public Health Surveill ; 9: e46264, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37428538

RESUMO

BACKGROUND: Functional limitations and disabilities have been associated with a decrease in cognitive function due to increasing age. Gait performance and cognitive function have been associated with gait variability in executive function, the phase domain in memory, and gait abnormalities in cognitive decline. OBJECTIVE: Our study aimed to investigate whether gait harmony was associated with cognitive function in the older adult population. Moreover, we aimed to investigate whether gait harmony was associated with cognitive function and explore each cognitive function in a specific harmonic state. METHODS: The study population included 510 adults aged ≥60 years who visited the Department of Neurology at the Veterans Health Service Medical Center, Seoul, South Korea. Gait data were collected using a 3D motion capture device with a wireless inertial measurement unit system. For cognitive function assessments, we used the Seoul Neuropsychological Screening Battery-Core test, which evaluates the level of cognitive function or impairment in 5 cognitive domains. RESULTS: In general, the association between the Seoul Neuropsychological Screening Battery-Core tests and the stance-to-swing ratio in the >1.63 ratio group yielded lower ß coefficients than those in the 1.50-1.63 ratio group. After adjustment for confounders, the odds ratio (OR) for the Digit Symbol Coding test (adjusted OR 0.42, 95% CI 0.20-0.88) and the Korean version of the Color Word Stroop Test: 60 seconds (adjusted OR 0.51, 95% CI 0.29-0.89) for frontal and executive function were significantly lower for the >1.63 ratio group than the reference group. CONCLUSIONS: Our findings suggest that the gait phase ratio is a valuable indicator of walking deficits and may also be associated with cognitive impairment in older adults.


Assuntos
Disfunção Cognitiva , Humanos , Idoso , Estudos Transversais , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/diagnóstico , Cognição , Marcha , Função Executiva
3.
BMC Geriatr ; 23(1): 332, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37248457

RESUMO

BACKGROUND: A link between sarcopenia and cognitive function has been proposed and is supported by several investigations. Nevertheless, the sex-linked relationship between these two diseases has been scarcely investigated. This cross-sectional study investigated sex differences in the association between sarcopenia and mild cognitive impairment. METHODS: We included all 286 participants aged 60 years or older with MCI who visited the Department of Neurology at Veterans Health Service Medical Center in South Korea from January to December 2021. The diagnosis of MCI was confirmed by two neurologists based on the participants' neuropsychological test scores. Diagnosis of sarcopenia was based on the algorithm of Asian Working Group for Sarcopenia (AWGS) 2019 including bioelectrical impedance analysis and handgrip strength, and cognitive function was assessed using Seoul Neuropsychological Screening Battery Core (SNSB-C) test. RESULTS: Among the 286 participants, 171 and 112 were men and women. After adjustment for potential covariates including APOE genotype, in women participants, there were significant associations between diagnosis of sarcopenia and MCI (OR = 4.72, 95%CI [1.39-15.97]), while there was no significant relationship in men participants. In eight subdomains of SNSB-C, we also found that women participants with sarcopenia demonstrated a significant memory decline (OR = 3.21, 95%CI [1.01-10.19]) as compared with the reference women group without sarcopenia after adjusting all covariates mentioned above. No significant association between any SNSB-C subdomain and MCI was demonstrated in men participants. CONCLUSIONS: We demonstrated that there was a different relationship between sarcopenia and MCI by sex and that sarcopenia may affect the cognitive subdomain differently by sex. These results imply that, with regard to cognitive function, maintaining muscle function and muscle mass might be more crucial for women than for men.


Assuntos
Disfunção Cognitiva , Sarcopenia , Humanos , Feminino , Masculino , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Força da Mão , Estudos Transversais , Caracteres Sexuais , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , República da Coreia/epidemiologia
4.
Polymers (Basel) ; 14(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36559758

RESUMO

Insulated gate bipolar transistor (IGBT) is an important power device for the conversion, control, and transmission of semiconductor power, and is used in various industrial fields. The IGBT module currently uses silicone gel as an insulating layer. Since higher power density and more severe temperature applications have become the trend according to the development of electronic device industry, insulating materials with improved heat resistance and insulation performances should be developed. In this study, we intended to synthesize a new insulating material with enhanced thermal stability and reduced thermal conductivity. Poly(imide-siloxane) (PIS) was prepared and crosslinked through a hydrosilylation reaction to obtain a semi-solid Crosslinked PIS. Thermal decomposition temperature, thermal conductivity, optical transparency, dielectric constant, and rheological property of the Crosslinked PIS were investigated and compared to those of a commercial silicone gel. The Crosslinked PIS showed high thermal stability and low thermal conductivity, along with other desirable properties, and so could be useful as an IGBT-insulating material.

5.
Medicine (Baltimore) ; 101(40): e30710, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36221417

RESUMO

Previous studies have reported that serum klotho and vitamin B12 levels are valuable aging-related markers. However, studies supporting the association between serum klotho and vitamin B12 levels are lacking. We investigated the association between serum klotho and vitamin B12 concentrations in adults in the United States. The analytic study sample was 2065 aged 40 to 79 who participated in the 2011 to 2014 National Health and Nutrition Examination Survey (NHANES). Serum klotho and vitamin B12 collected from adults who consented to the use of their samples in the future. The participants were divided into 2 groups based on estimated glomerular filtration rate (eGFR) levels (high: ≥90 mL/min/1.73 m2 or low: <90 mL/min/1.73 m2). Of the 2065 participants, the log-transformed klotho concentration was significantly correlated with log-transformed vitamin B12 in the high eGFR group, but not in the low eGFR group. After adjusting for all potential covariates, there was a significant association between klotho and vitamin B12 concentrations in the high eGFR groups (beta = 0.100, SE = 0.040). In contrast, there was no significant relationship between klotho and vitamin B12 concentrations in the low eGFR group (beta = 0.012, SE = 0.019). Serum klotho concentration was significantly associated with vitamin B12 increases in US adults with high kidney function. Vitamin B12 concentration may be an important marker of klotho concentration in older adults.


Assuntos
Envelhecimento , Vitamina B 12 , Idoso , Biomarcadores , Taxa de Filtração Glomerular , Glucuronidase , Humanos , Hidrolases , Inquéritos Nutricionais , Estados Unidos
6.
BMC Cardiovasc Disord ; 22(1): 442, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36221064

RESUMO

BACKGROUND: Klotho deficiency is a significant predictor of cardiovascular disease (CVD)-related mortality and morbidity. However, research assessing the association between klotho and individual risk factors of CVD is limited. This study aimed to explore the association between circulating serum klotho levels and risk factors for CVD in adults. METHODS: We used the 2007-2016 National Health and Nutrition Examination Survey and included 13,154 participants for whom serum klotho levels were available. Body mass index (BMI), exercise, smoking status, alcohol consumption, hypertension, dyslipidemia, serum lipid parameters, and blood pressure were considered as CVD risk factors. RESULTS: Circulating klotho levels were negatively associated with being overweight (beta coefficient: - 22.609, p = 0.0025), obesity (beta coefficient: - 23.716, p = 0.0011), current smoking (beta coefficient: - 46.412, p < 0.0001), and alcohol consumption (beta coefficient: - 51.194, p < 0.0001). There was a positive association between serum klotho levels and no history of dyslipidemia (beta coefficient: 15.474, p = 0.0053). Serum klotho levels were significantly decreased by a unit increase in triglycerides (beta coefficient: - 0.117, p = 0.0006) and total cholesterol (beta coefficient: - 0.249, p = 0.0002). There was a significant non-linear relationship between serum klotho levels, triglycerides, and total cholesterol. CONCLUSIONS: Lower serum klotho levels are associated with certain CVD risk factors, including high BMI, smoking, alcohol consumption, and lipid parameters (triglycerides and total cholesterol). This study suggests that the soluble klotho level may be a potential marker for CVD risk.


Assuntos
Doenças Cardiovasculares , Dislipidemias , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Colesterol , Dislipidemias/diagnóstico , Dislipidemias/epidemiologia , Humanos , Inquéritos Nutricionais , Fatores de Risco , Triglicerídeos
7.
Sci Total Environ ; 843: 156938, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35753483

RESUMO

Epigenetic aging is associated with harmful health effects such as oxidative stress from heavy metal exposure. We considered the relationship between genes and heavy metals in association with oxidative stress and then investigated the association between serum α- klotho and lead and cadmium exposure among adults in the United States from 2007 to 2016 participating in the National Health and Nutrition Examination Survey (NHANES). Samples included 9800 adults aged 40 to 79 years with measurements of serum α-klotho, lead and cadmium, and complete covariate data. Lead and cadmium levels were measured by inductively coupled plasma mass spectrometry and serum α-klotho levels were measured using enzyme-linked immunosorbent assay (ELISA). Multivariate linear regression analysis was used to estimate the association between serum α-klotho and blood lead, blood cadmium, and urinary cadmium. A percent increase in blood lead, blood cadmium, and urinary cadmium was associated with a statistically significant 4.0 % (p < 0.001), 2.0 %, (p = 0.003) and 1.0 % (p = 0.020) decrease in serum klotho. After adjustment, a percent increase in blood lead was associated with a statistically significant 4.0 % (p < 0.001) decrease in serum klotho; blood and urinary cadmium did not show any statistically significant associations after adjustment (ß (95 % CI), p-value for blood cadmium: 0.00 (-0.02-0.01), p = 0.573; urinary cadmium: -0.01 (-0.03-0.01), p = 0.210). Mean serum klotho levels showed a statistically significant decreasing trend with increasing blood lead quartiles (unadjusted and all-adjusted geometric means and 95 % confidence intervals of serum klotho (in pg/mL) for Q1, Q2, Q3, and Q4: unadjusted: 827.49 (814.20-840.92), 811.92 (794.73-829.48), 791.48 (775.11-808.19), and 772.01 (754.23-790.29); adjusted: 830.64 (805.53-856.45), 816.07 (789.18-843.87), 800.71 (773.71-828.57), and 784.31 (757.94-811.59)). Blood lead and levels were negatively associated with serum α-klotho levels in a representative population of US adults. These results suggest that blood lead levels may be associated with the serum levels of a protein associated with cognition and aging. Further research is recommended to investigate the causality behind such relationship.


Assuntos
Chumbo , Metais Pesados , Cádmio , Estudos Transversais , Inquéritos Nutricionais , Estados Unidos
8.
J Clin Med ; 11(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35629029

RESUMO

(1) Background: Several studies have reported that handgrip strength (HGS) may be a sign of lower cognitive performance. However, studies supporting an association between asymmetrical HGS and cognitive function are lacking. This study aimed to determine the association between asymmetrical HGS and cognitive performance among the elderly. (2) Methods: The study sample included 2729 individuals aged ≥60 years-old who participated in the 2011-2014 National Health and Nutrition Examination Survey. The cognitive tests consisted of the word learning and recall modules from the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), Animal Fluency Test, and Digit Symbol Substitution Test (DSST). HGS was measured using a handgrip dynamometer, and asymmetrical HGS was used to calculate HGS. (3) Results: Of the 2729 participants, 53.0% were aged 60 to 69 years-old, and 47.0% were aged 70 years and older. All cognitive performance scores were significantly correlated with asymmetrical HGS in both age groups. After adjusting for confounders, there was a significant association between DSST and HGS asymmetry in both age groups. Contrastingly, a significant association was only observed for the relationship between the CERAD test and HGS asymmetry in the ≥70 year-old group. (4) Conclusions: We found that low cognitive function was associated with asymmetrical HGS in elderly participants in the United States. Thus, asymmetrical HGS may be an important predictor of cognitive deficits. However, further research is required to confirm our results and to establish possible mechanisms.

9.
Nanomaterials (Basel) ; 12(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35564166

RESUMO

Graphene oxide-cysteamine-silver nanoparticle (GCA)/silver nanowire (AgNW)/GCA/colorless poly(amide-imide) (cPAI) structures based on cPAI substrates with polyimide and polyamide syntheses were fabricated to study their characteristics. A layer of electrodes was constructed using a sandwich structure-such as GCA/AgNW/GCA-with cPAI used as a substrate to increase the heat resistance and improve their mechanical properties. Furthermore, to overcome the disadvantages of AgNWs-such as their high surface roughness and weak adhesion between the substrate and electrode layers-electrodes with embedded structures were fabricated using a peel-off process. Through bending, tapping, and durability tests, it was confirmed that these multilayer electrodes exhibited better mechanical durability than conventional AgNW electrodes. Resistive random-access memory based on GCA/AgNW/GCA/cPAI electrodes was fabricated, and its applicability to nonvolatile memory was confirmed. The memory device had an ON/OFF current ratio of ~104@0.5 V, exhibiting write-once-read-many time characteristics, maintaining these memory characteristics for up to 300 sweep cycles. These findings suggest that GCA/AgNW/GCA/cPAI electrodes could be used as flexible and transparent electrodes for next-generation flexible nonvolatile memories.

10.
Aging (Albany NY) ; 14(6): 2537-2547, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351833

RESUMO

This study investigated the association between hyperuricemia and serum klotho protein levels in a representative sample of adults in the United States. We included 11,734 adults aged 40-80 years with available data of serum klotho, uric acid, covariates related to demographics, health behavior-related variables, and medical histories. Hyperuricemia was defined as a serum uric acid level of ≥7.0 mg/dL in men and ≥6.0 mg/dL in women. The geometric mean of serum klotho was 806.5 pg/mL (95% confidence interval: 801.7-811.4). The log-klotho level was negatively correlated with the uric acid level (r = -0.154; p < 0.0001). After adjustment for potential covariates, each one-unit increase in uric acid was significantly associated with a decrease in the log-klotho level (adjusted beta = -0.028; p < 0.0001). Compared with subjects without hyperuricemia, those with hyperuricemia had significantly lower serum klotho levels (adjusted beta = -0.062; p < 0.0001). We found a significant inverse association between serum uric acid and serum klotho levels in the general population, that is, an increase in serum uric acid levels was associated with a decrease in klotho levels. This finding suggests that loss of klotho may be due to the progression of hyperuricemia or, subsequently, gout.


Assuntos
Gota , Hiperuricemia , Proteínas Klotho , Ácido Úrico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Ácido Úrico/sangue
11.
Int J Mol Sci ; 22(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070927

RESUMO

Citric acid (CA), as an organic chelator, plays a vital role in alleviating copper (Cu) stress-mediated oxidative damage, wherein a number of molecular mechanisms alter in plants. However, it remains largely unknown how CA regulates differentially abundant proteins (DAPs) in response to Cu stress in Brassica napus L. In the present study, we aimed to investigate the proteome changes in the leaves of B. L. seedlings in response to CA-mediated alleviation of Cu stress. Exposure of 21-day-old seedlings to Cu (25 and 50 µM) and CA (1.0 mM) for 7 days exhibited a dramatic inhibition of overall growth and considerable increase in the enzymatic activities (POD, SOD, CAT). Using a label-free proteome approach, a total of 6345 proteins were identified in differentially treated leaves, from which 426 proteins were differentially expressed among the treatment groups. Gene ontology (GO) and KEGG pathways analysis revealed that most of the differential abundance proteins were found to be involved in energy and carbohydrate metabolism, photosynthesis, protein metabolism, stress and defense, metal detoxification, and cell wall reorganization. Our results suggest that the downregulation of chlorophyll biosynthetic proteins involved in photosynthesis were consistent with reduced chlorophyll content. The increased abundance of proteins involved in stress and defense indicates that these DAPs might provide significant insights into the adaptation of Brassica seedlings to Cu stress. The abundances of key proteins were further verified by monitoring the mRNA expression level of the respective transcripts. Taken together, these findings provide a potential molecular mechanism towards Cu stress tolerance and open a new route in accelerating the phytoextraction of Cu through exogenous application of CA in B. napus.


Assuntos
Brassica napus/efeitos dos fármacos , Ácido Cítrico/farmacologia , Cobre/toxicidade , Poluentes Ambientais/toxicidade , Proteínas de Plantas/genética , Proteoma/genética , Adaptação Fisiológica , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Catalase/genética , Catalase/metabolismo , Clorofila/biossíntese , Ácido Cítrico/metabolismo , Cobre/metabolismo , Poluentes Ambientais/antagonistas & inibidores , Poluentes Ambientais/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Anotação de Sequência Molecular , Peroxidases/classificação , Peroxidases/genética , Peroxidases/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Proteoma/classificação , Proteoma/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Estresse Fisiológico , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
12.
Nanomaterials (Basel) ; 10(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33260819

RESUMO

Graphene oxide (GO)-cysteamine-Ag nanoparticles (GCA)-silver nanowire (AgNW) fabricated by depositing GCA over sprayed AgNWs on PET films were proposed for transparent and flexible electrodes, and their optical, electrical, and mechanical properties were analyzed by energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, atomic force microscopy, scanning electron microscopy, transmission electron microscopy, current-voltage measurements, and bending test. GCA-AgNW electrodes show optical transmittance of >80% at 550 nm and exhibit a high figure-of-merit value of up to 116.13 in the samples with sheet resistances of 20-40 Ω/◻. It was observed that the detrimental oxidation of bare AgNWs over time was considerably decreased, and the mechanical robustness was improved. To apply the layer as an actual electrode in working devices, a Pt/GO/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate/GCA-AgNW/polyethylene terephthalate structure was fabricated, and resistive switching memory was demonstrated. On the basis of these results, we confirm that the proposed GCA-AgNW layer can be used as transparent and flexible electrode.

13.
Polymers (Basel) ; 11(9)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540300

RESUMO

Pyromellitic dianhydride (PMDA) and 4,4'-oxydianiline (ODA) oligoimide particles and PMDA-ODA poly(amic acid) salt (PAAS) were synthesized and used as stabilizers to prepare oil-in-water Pickering high internal phase emulsions (HIPEs). The stability of the Pickering HIPEs was investigated by dispersion stability analysis. Polyimide-based polyHIPEs could be prepared through freeze-drying and subsequent thermal imidization of the Pickering HIPEs. The characteristics of the polyHIPEs, including their morphology, porosity, thermal decomposition temperature, and compression modulus, were investigated. The thermal decomposition temperature (T10) of the polyHIPEs was very high (>530 °C), and their porosity was as high as 92%. The polyimide-based polyHIPEs have the potential to be used in high-temperature environments.

14.
Polymers (Basel) ; 11(3)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30960461

RESUMO

Polyimide films have conventionally been prepared by thermal imidization of poly(amic acid)s (PAAs). Here we report that the improvement of tensile strength while increasing (or maintaining) film flexibility of polyimide films was accomplished by simple microwave (MW) irradiation of the PAAs. This improvement in mechanical properties can be attributed to the increase in molecular weight of the polyimides by MW irradiation. Our results show that the mechanical properties of polyimide films can be improved by MW irradiation, which is a green approach that requires relatively low MW power, very short irradiation time, and no incorporation of any additional inorganic substance.

15.
Korean J Transplant ; 33(4): 135-145, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35769972

RESUMO

Background: This study aimed to develop and validate the Kidney Transplantation and Quality of Life (KTQoL) questionnaire to evaluate the quality of life (QoL) in Korean kidney transplantation (KT) patients. During the validation, the KTQoL was used to compare the QoL of KT patients before and after conversion from twice-daily to a once-daily regimen of tacrolimus. Methods: Construct and content validity of the 24-item KTQoL was evaluated using factor analysis and a panel of experts, respectively. The questionnaire was validated in 50 KT patients, conducted before and after conversion from twice-daily to once-daily tacrolimus. Internal consistency was evaluated based on Cronbach's alpha coefficient. Results: The KTQoL showed high internal consistency (Cronbach's alpha 0.71 to 0.88). Besides the Concerns category, both the general and specific QoL of KT patients were relatively good (≥70% of positive responses) and did not change markedly after conversion to the once-daily regimen (42.9±8.8 vs. 43.6±8.6, P=0.740). After conversion, men scored better than women in total KTQoL, Specific QoL, and Symptoms, while employed patients had better Daily Life scores and showed greater improvement in Daily Life scores compared with unemployed patients. Conclusions: The KTQoL seems to be a reliable instrument to evaluate general and specific QoL in Korean KT patients. Most patients evaluated their QoL positively. Conversion to once-daily tacrolimus had no significant effect on QoL in the total sample of KT patients. The QoL of men and/or employed persons might improve more after conversion to once-daily tacrolimus.

16.
Polymers (Basel) ; 10(8)2018 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-30960826

RESUMO

2,6-Diaminoanthracene (AnDA)-functionalized graphene oxide (GO) (AnDA-GO) was prepared and used to synthesize a graphene oxide-based polyimide (PI-GO) by the in-situ polymerization method. A PI-GO nanocomposite thin film was prepared and characterized by infrared (IR) spectroscopy, thermogravimetric analysis (TGA) and UV-visible spectroscopy. The PI-GO film was used as a memory layer in the fabrication of a resistive random access memory (RRAM) device with aluminum (Al) top and indium tin oxide (ITO) bottom electrodes. The device showed write-once-read-many-times (WORM) characteristics with a high ON/OFF current ratio (Ion/Ioff = 3.41 × 108). This excellent current ratio was attributed to the high charge trapping ability of GO. In addition, the device had good endurance until the 100th cycle. These results suggest that PI-GO is an attractive candidate for applications in next generation nonvolatile memory.

17.
Polymers (Basel) ; 10(10)2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30960996

RESUMO

A pyromellitic dianhydride (PMDA) and 4,4'-oxydianiline (ODA)-based oligoimide (PMDA-ODA) was synthesized by a one-step procedure using water as a solvent. The PMDA-ODA particles showed excellent partial wetting properties and were stably dispersed in both water and oil phases. A stable dispersion was not obtained with comparison PMDA-ODA particles that were synthesized by a conventional two-step method using an organic solvent. Both oil-in-water and water-in-oil Pickering emulsions were prepared using the oligoimide particles synthesized in water, and the size of the emulsion droplet was controlled based on the oligoimide particle concentration. The oligoimide particles were tested to prepare Pickering emulsions using various kinds of oils. The oil-in-water Pickering emulsions were successfully applied to prepare microcapsules of the emulsion droplets. Our new Pickering emulsion stabilizer has the advantages of easy synthesis, no need for surface modification, and the capability of stabilizing both oil-in-water and water-in-oil emulsions.

18.
Materials (Basel) ; 10(9)2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-28906465

RESUMO

Low-temperature self-healing capabilities are essential for self-healing materials exposed to cold environments. Although low-temperature self-healing concepts have been proposed, there has been no report of a microcapsule-type low-temperature self-healing system wherein the healing ability was demonstrated at low temperature. In this work, low-temperature self-healing of a microcapsule-type protective coating was demonstrated. This system employed silanol-terminated polydimethylsiloxane (STP) as a healing agent and dibutyltin dilaurate (DD) as a catalyst. STP underwent a condensation reaction at -20 °C in the presence of DD to give a viscoelastic product. The reaction behavior of STP and the viscoelasticity of the reaction product were investigated. STP and DD were separately microencapsulated by in situ polymerization and interfacial polymerization methods, respectively. The STP- and DD-loaded microcapsules were mixed into a commercial enamel paint, and the resulting formulation was applied to glass slides, steel panels, and mortars to prepare self-healing coatings. When the self-healing coatings were damaged at a low temperature (-20 °C), STP and DD were released from broken microcapsules and filled the damaged area. This process was effectively visualized using a fluorescent dye. The self-healing coatings were scratched and subjected to corrosion tests, electrochemical tests, and saline solution permeability tests. The temperature of the self-healing coatings was maintained at -20 °C before and after scratching and during the tests. We successfully demonstrated that the STP/DD-based coating system has good low-temperature self-healing capability.

19.
Korean J Intern Med ; 32(2): 269-276, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27255110

RESUMO

BACKGROUND/AIMS: Hepatic innervation in liver diseases is not fully understood. We here evaluated S100B expression as a marker of hepatic nerves in patients with various chronic liver diseases, topographically and semi-quantitatively. METHODS: Liver specimens were obtained from 70 subjects (three controls, and 32 chronic hepatitis B, 14 chronic hepatitis C, 14 liver cirrhosis, and seven hepatocellular carcinoma patients). The hepatic nerve density was calculated based on immunohistochemical staining of S100B protein in the portal tracts and hepatic lobules. S100B mRNA levels were semi-quantitatively assessed as the S100B/glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNA ratio. RESULTS: The densities of the hepatic nerves in portal tracts of chronic liver diseases were not significantly different from those of normal controls but the hepatic nerve densities in lobular areas of liver cirrhosis were significantly decreased (p = 0.025). Compared to the control, the S100B/GAPDH mRNA ratio was significantly decreased in chronic liver diseases (p = 0.006) and most decreased in chronic hepatitis C patients (p = 0.023). In chronic liver diseases, The S100B/GAPDH mRNA ratio tended to decrease as the fibrosis score > 0 (p = 0.453) but the overall correlation between the S100B/GAPDH mRNA ratio and fibrosis score was not statistically significant (r = 0.061, p = 0.657). CONCLUSIONS: Hepatic innervation is decreased in cirrhotic regenerating nodules compared to the control group and seems to decrease in early stages of fibrosis progression. Further studies are needed to clarify the association between changes of hepatic innervation and chronic liver disease progression.


Assuntos
Hepatopatias/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Estudos de Casos e Controles , Progressão da Doença , Hepatite B Crônica/genética , Hepatite B Crônica/metabolismo , Hepatite C Crônica/genética , Hepatite C Crônica/metabolismo , Humanos , Fígado/inervação , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Hepatopatias/genética , Hepatopatias/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/genética
20.
Clin Exp Emerg Med ; 3(4): 252-255, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28168232

RESUMO

A 77-year-old woman was admitted to a local clinic for altered consciousness and presented with a suspected basal ganglion hemorrhage detected on brain computed tomography. The patient was stuporous, but her vital signs were stable. Her initial blood glucose was 607 mg/dL, and a hyperdense lesion was found in the right basal ganglion on brain computed tomography. T1-weighted magnetic resonance imaging revealed high signal intensity in the right basal ganglion. Electroencephalography showed no seizure activity. The patient was treated with a fluid infusion, and serum glucose level was controlled with insulin. The patient gradually recovered consciousness and was alert within 24 hours as serum glucose level normalized. The basal ganglion lesion caused by hyperglycemia was not accompanied by involuntary limb movement. This is the first report of a patient presenting with decreased consciousness and typical neural radiographic changes associated with nonketotic hyperglycemia but without movement abnormalities.

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