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1.
Acc Chem Res ; 56(13): 1791-1802, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37342079

RESUMO

ConspectusColloidal nanocrystals (NCs) are composed of inorganic cores and organic or inorganic ligand shells and serve as building blocks of NC assemblies. Metal and semiconductor NCs are well known for the size-dependent physical properties of their cores. The large NC surface-to-volume ratio and the space between NCs in assemblies places significant importance on the composition of the NC surface and ligand shell. Nonaqueous colloidal NC syntheses use relatively long organic ligands to control NC size and uniformity during growth and to prepare stable NC dispersions. However, these ligands create large interparticle distances that dilute the metal and semiconductor NC properties of their assemblies. In this Account, we describe postsynthesis chemical treatments to engineer the NC surface and design the optical and electronic properties of NC assemblies. In metal NC assemblies, compact ligand exchange reduces the interparticle distance and drives an insulator-to-metal transition tuning the dc resistivity over a 1010 range and the real part of the optical dielectric function from positive to negative across the visible-to-IR region. Juxtaposing NC and bulk metal thin films in bilayers allows the differential chemical and thermal addressability of the NC surface to be exploited in device fabrication. Ligand exchange and thermal annealing densifies the NC layer, creating interfacial misfit strain that triggers folding of the bilayers and is used to fabricate, with only one lithography step, large-area 3D chiral metamaterials. In semiconductor NC assemblies, chemical treatments such as ligand exchange, doping, and cation exchange control the interparticle distance and composition to add impurities, tailor stoichiometry, or make entirely new compounds. These treatments are employed in longer studied II-VI and IV-VI materials and are being developed as interest in III-V and I-III-VI2 NC materials grows. NC surface engineering is used to design NC assemblies with tailored carrier energy, type, concentration, mobility, and lifetime. Compact ligand exchange increases the coupling between NCs but can introduce intragap states that scatter and reduce the lifetime of carriers. Hybrid ligand exchange with two different chemistries can enhance the mobility-lifetime product. Doping increases carrier concentration, shifts the Fermi energy, and increases carrier mobility, creating n- and p-type building blocks for optoelectronic and electronic devices and circuits. Surface engineering of semiconductor NC assemblies is also important to modify device interfaces to allow the stacking and patterning of NC layers and to realize excellent device performance. It is used to construct NC-integrated circuits, exploiting the library of metal, semiconductor, and insulator NCs, to achieve all-NC, solution-fabricated transistors.

2.
Ecotoxicol Environ Saf ; 281: 116652, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941657

RESUMO

Microalgal growth-based tests are international standards for ecotoxicity assessment; however, their long exposure times, large sample volumes, and reliance on a single growth-endpoint make them inadequate for rapid toxicity screening. Here, we aimed to develop a rapid and simple ecotoxicological test using the fast-growing green alga Mychonastes afer, with multiple endpoints-growth, lipid content, and photosynthesis. We exposed M. afer to two metals-silver and copper-and two herbicides-atrazine and diuron-for 24 h and identified the most sensitive and reliable endpoints for each toxicant: the maximum electron transport rate (ETRmax) for Ag, Cu and atrazine, and the lipid content for diuron. Lipid content was found to be both a sensitive and reliable biomarker, meeting the effluent limit guidelines in both the Republic of Korea and the USA. The sensitivity of M. afer to Ag and atrazine also closely matched the HC5 values derived from the species sensitivity distribution approach, confirming its reliability for setting regulatory concentrations of these contaminants. Our calculated predicted no-effect concentration (PNEC) values were similar to established European Union PNECs for Ag, Cu, atrazine, and diuron, underlining the utility of these biological endpoints for ecological risk assessment and regulatory decision making. This method required lower sample volume (2 mL vs 100 mL) and exposure time (24 h vs 72-120 h) than conventional green algal tests, and eliminated the need for labour-intensive cell counting, expensive equipment, and chlorophyll fluorescence measurement expertise. Overall, this M. afer test can be a valuable tool for the rapid screening of wastewater for metals and herbicides, contributing to environmental protection and management practices.


Assuntos
Atrazina , Cobre , Diurona , Ecotoxicologia , Herbicidas , Testes de Toxicidade , Poluentes Químicos da Água , Herbicidas/toxicidade , Diurona/toxicidade , Atrazina/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Testes de Toxicidade/métodos , Cobre/toxicidade , Ecotoxicologia/métodos , Fotossíntese/efeitos dos fármacos , Prata/toxicidade , República da Coreia , Haptófitas/efeitos dos fármacos , Monitoramento Ambiental/métodos , Clorófitas/efeitos dos fármacos
3.
Sensors (Basel) ; 23(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37631626

RESUMO

PURPOSE: This study aimed to verify whether bioelectrical impedance vector analysis (BIVA) can support the clinical evaluation of sarcopenia in elderly individuals and evaluate the relationships between phase angle (PhA), physical performance, and muscle mass. METHODS: The sample comprised 134 free-living elderly individuals of both sexes aged 69-91 years. Anthropometric parameters, grip strength, dual-energy X-ray absorptiometry findings, bioimpedance analysis results, and physical performance were also measured. The impedance vector distributions were evaluated in elderly individuals using BIVA. RESULTS: BIVA revealed significant differences between the sarcopenia and non-sarcopenia groups (both sexes). The sarcopenia group had a significantly lower PhA than the non-sarcopenia group in both sexes (p < 0.05). PhA was significantly correlated with age, appendicular skeletal muscle (ASM), handgrip strength (HGS), and muscle quality in both sexes and significantly correlated with ASM/Height2 and physical performance in males. CONCLUSION: BIVA can be used as a field assessment method in elderly Koreans with sarcopenia. PhA is a good indicator of muscle strength, muscle quality, and physical performance in males. These methods can help diagnose sarcopenia in elderly individuals with reduced mobility.


Assuntos
Força da Mão , Sarcopenia , Feminino , Masculino , Idoso , Humanos , Impedância Elétrica , Sarcopenia/diagnóstico , Força Muscular , República da Coreia
4.
BMC Oral Health ; 23(1): 832, 2023 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925400

RESUMO

BACKGROUND: Basketball is a sport with a higher injury rate. Regardless, few basketball players use mouthguards, which predisposes them to injuries. The use of mouthguards (UoM) could be related to several factors. This study aims to identify factors associated with UoM and to construct a model from the factors among basketball players in Indonesia. METHODS: Through convenience sampling, a total of 286 among basketball players in Indonesia was included in this cross-sectional study. These participants filled out online a modified questionnaires regarding demographic and several factors related to UoM. The data was analyzed using chi-square test, independent-sample t-test, binary logistic regression, and structural equation modeling (SEM). RESULTS: There were 286 players. 127 of them were males and 159 were females. Of them, 86 (30.1%) used mouthguards. Age, duration (in year), and weekly practicing basketball (in hour) were all significantly different between mouthguards users and non-users with (p = 0.005, p = 0.036 and p = 0.035), respectively. The UoM was significantly associated with level of awareness, injury experience, social support, and oral health professional (OHP) support with (p = 0.002, p < 0.001, p < 0.001 and p < 0.001), respectively. This result was also supported by a variety of variables' ORs, which range from 1.28 to 5.97. The coefficient of determination (R2) was 0.27. CONCLUSIONS: The UoM among basketball players in Indonesia was related to several factors, including the level of knowledge, level of awareness, duration of basketball career, injury experiences, social support, and oral health professionals' support which was constructed to propose a model. The model could explain 27% of the relationship between variables and UoM among Indonesian basketball players. This model will be useful for more comprehensive initiatives to promote oral health. It might be applicable for other countries as well as other sports communities / physical activities.


Assuntos
Basquetebol , Protetores Bucais , Masculino , Feminino , Humanos , Basquetebol/lesões , Indonésia , Estudos Transversais , Inquéritos e Questionários
5.
Arch Microbiol ; 204(7): 384, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689096

RESUMO

A Gram-stain-negative, anaerobic, non-motile, rod-shaped bacterium, designated as BGYT1T, was isolated from the feces of a cow in Andong, Republic of Korea. It was studied using a polyphasic method to determine its taxonomic position. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BGYT1T formed a lineage within the genus Olsenella and was most closely related to O. umbonate KCTC 15140T (98.2%). The complete genome sequence of strain BGYT1T was 2,476,083 bp long with a G + C content of 66.9 mol% and contained 1835 genes and 8 contigs. The N50 value was 604,117 bp. There were 50 tRNAs, 6 rRNAs (5S, 16S, 23S), 1778 CDSs and 2 BGCs and 1 tmRNA. The values for ANI (76.8%), AAI (67.3%), and dDDH (22.2%) compared to the closest related species were all below the threshold for bacterial species delineation. In addition, genes encoding the cell wall degrading enzymes such as chitinases, ß-1,3 glucanases, and proteases were also detected. The strain was able to grow at pH 6.0-8.0 (optimum, pH 7.0), in the presence of 0.5-1.5% NaCl (optimum, 0.5%, w/v) and at the temperature range of 35-40 °C (optimum, 35 °C). The predominant fatty acids were C16:0 DMA (20.2%), C16:0 (20.2%), C18:0 (10.5%) and C18:1 cis 9 (17.0%). The polar lipids consisted of an unidentified phospholipid, four unidentified glycolipids and three unidentified lipids. Based on its phenotypic analyses, phylogenetic and physiological characteristics, strain BGYT1T represented a novel species within the genus Olsenella, for which the name Olsenella intestinalis sp. nov. is proposed. The type strain is BGYT1T (= KCTC 25379T = GDMCC 1.3011T).


Assuntos
Actinobacteria , Actinobacteria/genética , Animais , Técnicas de Tipagem Bacteriana , Bovinos , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
J Korean Med Sci ; 37(20): e141, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35607738

RESUMO

BACKGROUND: The impact of the coronavirus disease 2019 (COVID-19) pandemic on Kawasaki disease (KD) has not yet been established. We investigated changes in the observed number and severity of KD cases and accompanying coronary artery complications during the COVID-19 pandemic in Korea. METHODS: This retrospective observational study included patients aged < 18 years with acute-phase KD diagnosed between March 2018 and February 2021. Data were extracted from the Clinical Data Warehouse that houses data from five affiliated university hospitals in Korea. We analyzed changes in the number of patient admissions and clinical characteristics, including cardiac complications, before and after the onset of the COVID-19 pandemic. RESULTS: A total of 475 admissions were included in the analysis. After March 2020, we observed a significant decrease of 33% in the number of hospitalizations for KD compared with the average number of hospitalizations during the previous 2 years. The number of admissions per month significantly decreased by 7.9 persons/month (95% confidence interval, -13.8 to -2.0; P < 0.05) compared with that before COVID-19. By contrast, the proportion of patients aged < 1 year with KD increased. The proportion of patients with refractory KD and the rate of cardiac complications did not change significantly. CONCLUSION: Since the onset of the COVID-19 pandemic, the total number of hospital admissions for KD has decreased in Korea. Although the proportion of admissions of infants aged < 1 year increased, no changes were observed in clinical courses and complications.


Assuntos
COVID-19 , Síndrome de Linfonodos Mucocutâneos , COVID-19/epidemiologia , Hospitalização , Humanos , Lactente , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Pandemias , SARS-CoV-2
7.
Angew Chem Int Ed Engl ; 61(47): e202212676, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36193684

RESUMO

Electrochemical nitrogen reduction reaction (NRR) under ambient conditions has attracted considerable scientific and engineering interest as a green alternative route for NH3 production. Molybdenum is a promising candidate as an electrocatalyst for NRR as it has a suitable binding strength with N species. However, the design of an efficient Mo-based catalyst remains elusive. To enhance the selectivity of NRR toward NH3 , we have developed a carbon nanofiber catalyst embedded with molybdenum and cobalt (Co-Mo-CNF). Co with a strong ability to dissociate water enhances local proton source near Mo, where the hydrogenation step of the NRR occurs. A NH3 formation rate of 72.72 µg h-1 mg-1 and a Faradaic efficiency of 34.5 % were obtained at -0.5 V vs. RHE. We also attempted to provide a mechanistic understanding of the NRR via in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) and isotopic labeling experiments using 15 N2 and D2 O.

8.
Angew Chem Int Ed Engl ; 61(51): e202214541, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36274053

RESUMO

NiFe-based oxides are one of the best-known active oxygen evolution electrocatalysts. Unfortunately, they rapidly lost performance in Fe-purified KOH during the reaction. Herein, tetraphenylporphyrin (TPP) was loaded on a catalyst/electrolyte interface to alleviate the destabilization of NiFe (oxy)hydroxide. We propose that the degradation occurs primarily due to the release of thermodynamically unstable Fe. TPP acts as a protective layer and suppresses the dissolution of hydrated metal at the catalyst/electrolyte interface. In the electric double layer, the nonpolar TPP layer on the NiFe surface also invigorates the redeposition of the active site, Fe, which leads to prolonging the lifetime of NiFe. The TPP-coated NiFe was demonstrated in anion exchange membrane water electrolysis, where hydrogen was generated at a rate of 126 L h-1 for 115 h at a 1.41 mV h-1 degradation rate. Consequently, TPP is a promising protective layer that could stabilize oxygen evolution electrocatalysts.

9.
Chem Rec ; 21(4): 820-840, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33645913

RESUMO

Capacitive deionization (CDI) is a potential technology to provide cost efficient desalinated and/or softened water. Several efforts have been invested in the fabrication of CDI electrodes that not only has outstanding performance but also high chance of large scalability. In this personal account, the different techniques in developing carbon-based materials are presented together with its actual effect on the surface and electrochemical properties of carbon. The categories presented are based on the studies done by the Electrochemical Reaction and Technology Laboratory, the Ertl Center, different research groups in South Korea, and selected papers from the past three years. Our perspective about research gaps and prospects are also included with the aim to increase interest for CDI research.

10.
Int J Mol Sci ; 22(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670407

RESUMO

Natural compounds such as herbal medicines and/or phyto-compounds from foods, have frequently been used to exert synergistic therapeutic effects with anti-brain disorder drugs, supplement the effects of nutrients, and boost the immune system. However, co-administration of natural compounds with the drugs can cause synergistic toxicity or impeditive drug interactions due to changes in pharmacokinetic properties (e.g., absorption, metabolism, and excretion) and various drug transporters, particularly brain transporters. In this review, natural compound-drug interactions (NDIs), which can occur during the treatment of brain disorders, are emphasized from the perspective of pharmacokinetics and cellular transport. In addition, the challenges emanating from NDIs and recent approaches are discussed.


Assuntos
Barreira Hematoencefálica/metabolismo , Encefalopatias/tratamento farmacológico , Proteínas de Membrana Transportadoras/metabolismo , Compostos Fitoquímicos , Plantas Medicinais , Animais , Transporte Biológico , Barreira Hematoencefálica/patologia , Encefalopatias/metabolismo , Encefalopatias/patologia , Interações Medicamentosas , Humanos , Compostos Fitoquímicos/agonistas , Compostos Fitoquímicos/antagonistas & inibidores , Compostos Fitoquímicos/farmacocinética , Compostos Fitoquímicos/uso terapêutico
11.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206616

RESUMO

The biophysical properties of therapeutic antibodies influence their manufacturability, efficacy, and safety. To develop an anti-cancer antibody, we previously generated a human monoclonal antibody (Ab417) that specifically binds to L1 cell adhesion molecule with a high affinity, and we validated its anti-tumor activity and mechanism of action in human cholangiocarcinoma xenograft models. In the present study, we aimed to improve the biophysical properties of Ab417. We designed 20 variants of Ab417 with reduced aggregation propensity, less potential post-translational modification (PTM) motifs, and the lowest predicted immunogenicity using computational methods. Next, we constructed these variants to analyze their expression levels and antigen-binding activities. One variant (Ab612)-which contains six substitutions for reduced surface hydrophobicity, removal of PTM, and change to the germline residue-exhibited an increased expression level and antigen-binding activity compared to Ab417. In further studies, compared to Ab417, Ab612 showed improved biophysical properties, including reduced aggregation propensity, increased stability, higher purification yield, lower pI, higher affinity, and greater in vivo anti-tumor efficacy. Additionally, we generated a highly productive and stable research cell bank (RCB) and scaled up the production process to 50 L, yielding 6.6 g/L of Ab612. The RCB will be used for preclinical development of Ab612.


Assuntos
Anticorpos Monoclonais/química , Modelos Moleculares , Molécula L1 de Adesão de Célula Nervosa/química , Engenharia de Proteínas , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/farmacologia , Afinidade de Anticorpos , Células CHO , Fenômenos Químicos , Cricetulus , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Molécula L1 de Adesão de Célula Nervosa/antagonistas & inibidores , Engenharia de Proteínas/métodos , Estabilidade Proteica , Termodinâmica
12.
Int J Med Microbiol ; 310(2): 151391, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32007342

RESUMO

Lactobacillus plantarum has been identified as a probiotic bacterium owing to its role in immune regulation and maintenance of intestinal permeability. Here, we investigated the anti-colitic effects and mechanism of L. plantarum CBT LP3 (LP3). This in vivo study was performed using dextran sodium sulfate (DSS) to induce colitis in mice. Mice were randomly divided into three groups: a control supplied with normal drinking water, a DSS-treated group followed by oral administration of vehicle, and a DSS-treated group gavaged with LP3 daily for 7 days following DSS administration. An analysis of macrophages and T cell subsets harvesting from peritonium cavity cells and splenocytes was performed using a flow cytometric assay. Gene expression and cytokine profiles were measured using quantitative reverse transcriptase polymerase chain reaction. The administration of LP3 significantly attenuated disease activity and histolopathology compared to control. LP3 had anti-inflammatory effects, with increased induction of regulatory T cells and type 2 helper T cells in splenocytes and restoration of goblet cells accompanied by suppression of proinflammatory cytokine expressions. These findings suggest that L. plantarum CBT LP3 can be used as a potent immunomodulator, which has significant implications for IBD treatment.


Assuntos
Colite/imunologia , Colite/terapia , Lactobacillus plantarum , Probióticos/uso terapêutico , Subpopulações de Linfócitos T/imunologia , Animais , Colite/induzido quimicamente , Citocinas/imunologia , Sulfato de Dextrana , Modelos Animais de Doenças , Fatores Imunológicos/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/imunologia , Células Th2/imunologia
13.
Biotechnol Bioeng ; 117(9): 2897-2910, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32510167

RESUMO

Core binding factor ß (Cbfß) is a non-DNA binding cofactor of Runx2 that potentiates DNA binding. Previously, it has been reported that Cbfß plays an essential role in osteogenic differentiation and skeletal development by inhibition adipogenesis. Here, we delivered the recombinant Cbfß protein into human mesenchymal stem cells (MSCs) and triggered osteogenic lineage commitment. The efficient delivery of Cbfß was achieved by fusing 30Kc19 protein, which is a cell-penetrating protein derived from the silkworm. After the production of the recombinant Cbfß-30Kc19 protein in the Escherichia coli expression system, and confirmation of its intracellular delivery, MSCs were treated with the Cbfß-30Kc19 once or twice up to 300 µg/ml. By investigating the upregulation of osteoblast-specific genes and phenotypical changes, such as calcium mineralization, we demonstrated that Cbfß-30Kc19 efficiently induced osteogenic differentiation in MSCs. At the same time, Cbfß-30Kc19 suppressed adipocyte formation and downregulated the expression of adipocyte-specific genes. Our results demonstrate that the intracellularly delivered Cbfß-30Kc19 enhances osteogenesis in MSCs, whereas it suppresses adipogenesis by altering the transcriptional regulatory network involved in osteoblast-adipocyte lineage commitment. Cbfß-30Kc19 holds great potential for the treatment of bone-related diseases, such as osteoporosis, by allowing transcriptional regulation in MSCs, and overcoming the limitations of current therapies.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Subunidade beta de Fator de Ligação ao Core , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Proteínas Recombinantes de Fusão , Adipócitos/efeitos dos fármacos , Peptídeos Penetradores de Células/genética , Células Cultivadas , Subunidade beta de Fator de Ligação ao Core/genética , Subunidade beta de Fator de Ligação ao Core/farmacocinética , Subunidade beta de Fator de Ligação ao Core/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Espaço Intracelular/metabolismo , Osteoblastos/efeitos dos fármacos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/farmacologia
14.
Chem Rec ; 20(2): 89-101, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31490626

RESUMO

Electrochemical reduction of carbon dioxide (CO2 ) to valuable organic compounds is promising as to recycling of carbon source of CO2 and technical compatibility with systems using renewable energy resources. In recent years, considerable efforts have been devoted to the research field of CO2 conversion using electrocatalysis. This personal account particularly focuses on the recent progress that has been achieved by the Ertl Center and a number of groups in South Korea that becomes one of the larger CO2 emitters. The research trends of catalyst development divided into different categories according to the primary products are presented first. Afterwards, several studies on theoretical calculations and electrolytic reactors are reviewed taking into account the fundamental understanding and feasibility of the CO2 electroreduction. Finally, a perspective on the challenges and needs in achieving the advanced level of research and development is presented.

15.
J Pediatr Nurs ; 52: e15-e20, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31785967

RESUMO

PURPOSE: This study utilized data from the Korea Youth Risk Behavior Survey to examine gender differences in the impact of sexual initiation, and age at sexual initiation, on depressive symptoms among Korean adolescents. DESIGN AND METHODS: This study performed a secondary analysis of cross-sectional data from the 14th Korea Youth Risk Behavior Survey (2018). Data from 60,040 adolescents aged 12-18 were included in this study. The relationship between sexual experience, age at initiation, and depressive symptoms was analyzed with complex sample multiple logistic regression. RESULTS: Overall, 5.7% of participants declared having had sexual experience. Sexual initiation tended to occur from grade 7 and above. In addition, 33.6% of girls and 21.1% of boys reported having depressive symptoms. Depressive symptoms were associated with sexual initiation experience, but depression symptoms were not associated with the timing of sexual initiation. CONCLUSIONS: This study provides preliminary evidence of a relationship between sexual experience and depressive symptoms among adolescents; however, this relationship appeared independent of the timing of sexual initiation. These findings suggest that sexually active adolescents should be screened for depressive symptoms, regardless of gender. PRACTICE IMPLICATIONS: This is the first study to examine the impact of sexual initiation and its timing on depressive symptoms among Korean adolescents. Sexual behaviors of Korean adolescents should be accounted for during the development of mental health policies aimed at young people. In addition, sexually active adolescents should be screened and monitored for depressive symptoms.


Assuntos
Comportamento do Adolescente , Depressão , Adolescente , Criança , Estudos Transversais , Depressão/diagnóstico , Depressão/epidemiologia , Feminino , Humanos , Masculino , República da Coreia/epidemiologia , Assunção de Riscos , Caracteres Sexuais , Comportamento Sexual
16.
Molecules ; 25(8)2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32294941

RESUMO

Recently, potent neuroprotective and anti-diabetic effects of 7ß-(3-Ethyl-cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (ECN), a sesquiterpenoid isolated from Tussilago farfara Linnaeus, have been elucidated. To facilitate further pre-clinical evaluation in rats, an analytical method for the determination of ECN in rat plasma was developed and optimized by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Plasma samples were pretreated by the protein precipitation method with an acetonitrile solution of losartan (LST) as the internal standard. Chromatographic separation was performed using a an Octadecyl-silica (ODS) column (2.6 µm, 100 x 4.6 mm) in the isocratic mode. The mobile phase, comprising 10 mM ammonium formate in water pH 5.75) and acetonitrile (11:89, v/v), was eluted at a flow rate of 0.4 mL/min. Mass spectrometric detection was performed in the multiple reaction monitoring mode with positive electrospray ionization, and the mass transitions of ECN and LST were m/z 431.3 to 97.3 and m/z 423.1 to 207.2, respectively. The calibration curves of spiked plasma samples were linear in the 10.0-10,000 ng/mL range (r2 > 0.996). The lower limit of quantification (LLOQ) was determined as 10.0 ng/mL. Validation was conducted in the LLOQ, and three quality control (QC) sample levels (10.0, 25.0, 3750, and 7500 ng/mL) were studied. Among them, the relative standard deviation for the within- and between-run precisions was under 9.90%, and the relative error of the accuracies was within the -8.13% to 0.42% range. The validated method was successfully employed to investigate the pharmacokinetic properties of ECN in rats, which revealed the linear pharmacokinetic behavior of ECN for the first time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/farmacocinética , Sesquiterpenos/farmacocinética , Espectrometria de Massas em Tandem/métodos , Acetonitrilas/química , Administração Oral , Animais , Calibragem , Cromatografia Líquida de Alta Pressão/instrumentação , Formiatos/química , Limite de Detecção , Losartan/química , Masculino , Farmacocinética , Extratos Vegetais/sangue , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Controle de Qualidade , Ratos , Ratos Sprague-Dawley , Sesquiterpenos/administração & dosagem , Sesquiterpenos/sangue , Sesquiterpenos/química , Espectrometria de Massas em Tandem/instrumentação , Tussilago/química
17.
J Nanosci Nanotechnol ; 19(3): 1269-1275, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469174

RESUMO

Icing of railway contact wires in the cold climates of the USA, Canada, China, Japan, and South Korea can cause significant problems and delays in the operation schedules of electric-powered trains and subway cars. As anti-icing methods, manual de-icing, contact-wire thermal running, resistive-wire-heating de-icing, and chemical de-icing have all been explored and tested. Among them, environmentally friendly chemical de-icing based on the same concept as that of automobileengine antifreezer can be practically effective for application to contact wires at railcar depots. In the present study, the railway contact wires are coated with anti-icing mixtures of ethylene glycol/tap water and glycerol/tap water at various ratios (v/v %) as well as with tap water alone, at temperatures of -30 and -40 °C in a deep freezer. The morphological change on the wire surfaces is observed under optical microscopy. The surface-contact angles are measured to examine the surface difference between uncoated and coated railway contact-wire fragments. Conclusively, the fragments coated with 40/60 and 60/40 (v/v %) ratios of ethylene glycol or glycerol with tap water, as compared with the uncoated fragments, are shown to have been effectively de-iced. The surface-characterizations data thus indicate that mixtures of glycerol or ethylene glycol with tap water can be practical de-icing agents for application to railway contact wires.

18.
J Pediatr Nurs ; 46: e2-e9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30770158

RESUMO

PURPOSE: The purpose of this study was to evaluate the effects of a social support program on the stress, anxiety, guilt, and life satisfaction levels among Korean mothers of children with precocious puberty. DESIGN AND METHODS: A non-equivalent control group and a non-synchronized design were used in this quasi-experiment study. Thirty-four mothers (divided into equal-sized experimental and control groups), 32-47 years of age, with children aged 6-11 years old, were recruited from a pediatric outpatient department at a national university hospital. The experimental group was involved in four sessions of a 4-week social support program. Descriptive statistics were used for demographic characteristics. Chi-square tests and t-tests were used to evaluate group differences. RESULTS: The program significantly reduced mothers' stress and guilt and significantly increased their life satisfaction. No significant differences in changes in anxiety were reported between the groups. CONCLUSIONS: This study confirms that the social support program was a useful nursing intervention for Korean mothers of children with precocious puberty, which can be extensively applied to help mothers in similar situations. PRACTICE IMPLICATIONS: The preliminary study findings may inform healthcare professionals to develop effective interventions to promote psychosocial well-being of mothers of children with precocious puberty through strengthening their social support and to further improve the quality of life of children with precocious puberty and their families.


Assuntos
Mães/psicologia , Puberdade Precoce , Apoio Social , Adulto , Criança , Feminino , Humanos , Pessoa de Meia-Idade , República da Coreia
19.
Molecules ; 24(10)2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31121831

RESUMO

Aminoacyl-tRNA synthetase complex-interacting multifunctional protein 1 (AIMP1)-derived peptide (AdP) has been developed as a cosmeceutical ingredient for skin anti-aging given its fibroblast-activating (FA) and melanocyte-inhibiting (MI) functions. However, a suitable strategy for the topical delivery of AdP was required due to its low-permeable properties. In this study, FA and MI domains of AdP (FA-AdP and MI-AdP, respectively) were determined by functional domain mapping, where the activities of several fragments of AdP on fibroblast and melanocyte were tested, and a hydrosol-based topical delivery system for these AdP fragments was prepared. The excipient composition of the hydrosol was optimized to maximize the viscosity and drying rate by using Box-Behnken design. The artificial skin deposition of FA-AdP-loaded hydrosol was evaluated using Keshary-Chien diffusion cells equipped with Strat-M membrane (STM). The quantification of the fluorescent dye-tagged FA-AdP in STM was carried out by near-infrared fluorescence imaging. The optimized hydrosol showed 127-fold higher peptide deposition in STM than free FA-AdP (p < 0.05). This work suggests that FA- and MI-AdP are active-domains for anti-wrinkle and whitening activities, respectively, and the hydrosol could be used as a promising cosmetic formulation for the delivery of AdPs to the skin.


Assuntos
Cosmecêuticos/farmacologia , Citocinas/química , Proteínas de Neoplasias/química , Peptídeos/farmacologia , Proteínas de Ligação a RNA/química , Envelhecimento da Pele/efeitos dos fármacos , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cosmecêuticos/química , Doxorrubicina , Humanos , Melanócitos/citologia , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Camundongos , Modelos Biológicos , Imagem Óptica , Peptídeos/química , Viscosidade
20.
BMC Oral Health ; 19(1): 168, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357960

RESUMO

BACKGROUND: The purpose of this study was to evaluate the mitigating effect of the use of interdental brushes on periodontal health inequality. METHODS: This study was based on the data acquired in the Sixth Korea National Health and Nutrition Examination Survey (KNHANES VI; 2013-2015). A total of 17,583 participants (7,633 males and 9,950 females)) aged 19 years or older completed the KNHANES VI between 2013 and 2015. Multivariable logistic regression analysis was performed using socioeconomic characteristics (sex, age, level of education, individual income), personal health practice (smoking, toothbrushing, dental flossing, interdental brushing, dental clinic visiting), systematic medical factors (diabetes mellitus, hypercholesterolemia, hypertension, obesity) and the community periodontal index. We confirmed differences in the prevalence of periodontal disease with the use of an interdental brushes stratified according to individual income. RESULTS: Three logistic regression models adjusted for covariates hierarchically. In all models, individuals who used an interdental brush were not significantly different from individuals who did not use an interdental brush. The adjusted odds ratio (OR) for interdental brushing was 0.918 with a 95% confidence intervals (CIs) of 0.797-1.057. When periodontal disease was the outcome of the model, the lowest income group had 1.266 (95% CIs 1.066 to 1.502) times the odds of having periodontal disease than the highest income group. In interdental brush nonusers, the lowest income group had 1.276 (95% CI 1.061-1.533) times the odds of having periodontal diseases than the highest income group. However, in the interdental brush users, there were no significant differences in periodontal disease prevalence among income groups. CONCLUSIONS: The results suggest that the use of interdental brushes could alleviate periodontal health inequality.


Assuntos
Povo Asiático/estatística & dados numéricos , Cárie Dentária/prevenção & controle , Dispositivos para o Cuidado Bucal Domiciliar , Disparidades nos Níveis de Saúde , Higiene Bucal/métodos , Periodontite/prevenção & controle , Escovação Dentária/métodos , Adulto , Idoso , Dispositivos para o Cuidado Bucal Domiciliar/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Higiene Bucal/instrumentação , Periodontite/epidemiologia , República da Coreia/epidemiologia , Escovação Dentária/instrumentação , Adulto Jovem
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