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1.
Int J Biol Macromol ; 209(Pt B): 1665-1675, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35487373

RESUMO

Current hydrogel strain sensors have met assorted essential requirements of wearing comfort, mechanical toughness, and strain sensitivity. However, an increment in the toughness of a hydrogel usually leads to an increase in elastic moduli that could be unfavorable for wearing comfort. In addition, traits of biofriendly and sustainability require synthesis of the hydrogels from natural polymer-based networks. We propose a novel strategy to fabricate an ionic conductive organohydrogel from natural biological macromolecule "gelatin" and polyacid "tannic acid" to resolve these challenges. Tannic acid modified the structure of the gelatin network in the ionic conductive organohydrogels, that not only led to an increase in toughness accompanying a decrease in elastic moduli but also headed to higher strain sensitivity and tunability. The proposed methodology exhibited tunable tensile modulus from 27 to 13 kPa, tensile strength from 287 to 325 kPa, elongation at fracture from 510 to 620%, toughness from 500 to 550 kJ/m3, conductivity from 0.29 to 0.8 S/m, and strain sensitivity (GF = 1.4-6.5). Moreover, the proposed organohydrogel exhibited excellent freezing tolerance. This study provides a facile yet powerful strategy to tune the mechanical and electrical properties of organohydrogels which can be adapted to various wearable sensors.


Assuntos
Gelatina , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Hidrogéis/química , Íons , Taninos
2.
ACS Appl Mater Interfaces ; 13(2): 3463-3470, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33416317

RESUMO

With rapid advances in flexible electronics, transparent conductive electrodes (TCEs) have also been significantly developed as alternatives to the conventional indium tin oxide (ITO)-based material systems that exhibit low mechanical flexibility. Nanomaterial-based alternating materials, such as graphene, nanowire, and nanomesh, exhibit remarkable properties for TCE-based applications, such as high electrical conductivity, high optical transparency, and high mechanical stability. However, these nanomaterial-based systems lack scalability, which is a key requirement for practical applications, and exhibit a size-dependent property variation and inhomogeneous surface uniformity that limit reliable properties over a large area. Here, we exploited a conventional ITO-based material platform; however, we incorporated a transparent molecular adhesive, 4-aminopyridine (4-AP), to improve mechanical flexibility. While the presence of 4-AP barely affected optical transmittance and sheet resistance, it improved interfacial adhesion between the substrate and ITO as well as formed a wavy surface, which could improve the mechanical flexibility. Under various mechanical tests, ITO/4-AP/poly(ethylene terephthalate) (PET) exhibited remarkably improved mechanical flexibility as compared with that of ITO/PET. Furthermore, ITO/4-AP/PET was utilized for a flexible Joule heater application having spatial uniformity of heat generation, voltage-dependent temperature control, and mechanical flexibility under repeated bending tests. This molecular adhesive could overcome the current limitations of material systems for flexible electronics.

3.
Biomater Sci ; 8(19): 5427-5440, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32996919

RESUMO

Fibroblast-derived extracellular matrix (fECM)-supported scaffolds made up of poly(lactic-co-glycolic acid) were prepared with the enhanced preservation of ECM components by composites with magnesium hydroxide nanoparticles (MH NPs), and were applied for the renal tissue regeneration. MH NP utilization resulted in an increased ECM protein amount, decreased scaffold degradation, and surface hydrophilic modification. These effects were correlated with the improved adhesion and viability of renal proximal tubule epithelial cells on the scaffold. In vivo experiments demonstrated effects of fECM and MH NPs on renal regeneration. The number of glomeruli was the largest in the ECM scaffold with MH NPs as compared to the pristine scaffold and ECM scaffold without MH NPs. Quantitative PCR analysis exhibited less inflammation (IL-1ß, TNF-α, and IL-6) and fibrosis-related (vimentin, collagen I, and α-SMA) markers, whereas opposite results were found in regeneration-related markers (Pax2, vWf, Wt1, and Emx2). The concentration of renal function-related molecules, creatinine and blood urea nitrogen diminished in the ECM scaffold with MH NPs. All results indicate that MH NPs utilization for the renal regenerative scaffold is effective for in vitro and in vivo environments and is, therefore, a good model for regeneration of kidneys and other tissues, and organs.


Assuntos
Nanopartículas , Alicerces Teciduais , Matriz Extracelular , Rim , Hidróxido de Magnésio , Engenharia Tecidual
4.
Korean J Women Health Nurs ; 25(3): 285-298, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37679920

RESUMO

PURPOSE: The purpose of this study was to identify the impacts of human papillomavirus (HPV) vaccination-related health belief, attitudes toward HPV vaccination, and subjective norms on HPV vaccination intent targeting mothers of elementary school daughters. METHODS: The study use a correlative survey design. The subjects of the study were 121 mothers of elementary school daughters located in metropolitan city B. All subjects agreed to participate in the study. The data were collected from September 1 to October 18, 2018, and were analyzed using descriptive statistics, Independent t-test, ANOVA with a post hoc Scheffé test, Pearson's correlation coefficients, and stepwise multiple regression. RESULTS: Attitude toward HPV vaccination, subjective norms, vaccination plans for their children, and mother's vaccination status were significant factors influencing HPV vaccination intention. These factors accounted for 72% of the HPV vaccination intention. CONCLUSIONS: This study showed that factors affecting the intention of mothers of elementary school daughters to vaccinate against HPV were HPV vaccination attitudes, subjective norms, vaccination plans for their children, and mother's vaccination status. The biggest influencing factor was HPV vaccination attitudes. Therefore, in order to encourage mothers of elementary school daughters to vaccinate against HPVs, national-level policies should be implemented to create a social atmosphere of positive attitudes toward HPV vaccinations that also emphasizes how easy it is to get vaccinated against HPV. Based on this, mothers of elementary school daughters should be encouraged to have them vaccinated against HPV, thus contributing to improving the HPV vaccination rates of elementary school girls.

5.
Korean J Women Health Nurs ; 25(1): 86-98, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37679932

RESUMO

PURPOSE: The purpose of the study was to determine effect of incivility, resilience, and social support experienced by nursing students on burnout in clinical practice. METHODS: Subjects were 140 nursing students who agreed to participate in this study. Collected data were analyzed using descriptive statistics, t-test, analysis of variance, Pearson's correlation and stepwise multiple regression with SPSS WIN 23.0 program. RESULTS: Burnout showed significantly positive correlation with incivility but significantly negative correlations with resilience and social support. Factors affecting burnout were satisfaction with major-dissatisfaction, satisfaction with major-average, social support, grade, and relationship with peers. Satisfaction with major (dissatisfaction) had the greatest effect on burnout, explaining 41% of the total variance. CONCLUSION: According to this study, dissatisfaction with major was identified as the most significant factor influencing burnout of nursing students in clinical practice. Therefore, it is important to develop and implement programs that can reduce dissatisfaction with major and increase social support and relationship with peers in order to lower burnout of nursing students. In addition, a systemic management of fourth-grade students with a high level of clinical practice is necessary to reduce the level of clinical practice. The authors declared no conflict of interest.

6.
Org Lett ; 20(24): 7869-7874, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30511868

RESUMO

Regio- and stereoselective synthesis of ( E)-3-arylmethyleneisoindolin-1-ones via Pd(II)/Cu(II)-catalyzed one-pot C-C/C-N bond forming sequence between amides and styrenes is reported. This method provides facile and rapid access to a diverse range of such compounds using readily available starting materials under mild aerobic conditions with good functional group tolerance and high selectivity and efficiency. Further elaboration of the products obtained from this process enabled very short and efficient syntheses of aristolactam and indoloisoquinolinone alkaloids.

7.
Korean J Women Health Nurs ; 21(3): 197-206, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37684824

RESUMO

PURPOSE: The purpose of this study was to examine the effects of light therapy on sleep disturbance and depression in climacteric women with menopausal symptoms. METHODS: The research design was a nonequivalent control group pre test-post test design. Data were collected from September 29, 2013 to November 11, 2013. Participants included 17 climacteric women in an artificial light therapy group, 17 climacteric women in a sun light therapy group and 16 climacteric women in a control group. Measures consisted of the sleep disturbance, depression, melatonin, and serotonin. RESULTS: There was a statistically significant difference of Korean Sleep Scale A (F=53.87, p<.001), and melatonin (F=31.19, p<.001) among three groups. There was a statistically significant difference of Self-Rating Depression Scale (F=121.86, p<.001), and serotonin (F=102.37, p<.001) among three groups. CONCLUSION: Artificial and sun light therapy can be applied as a supportive nursing intervention to subjects with sleep disturbance and depression in climacteric women with menopausal symptoms. Artificial and sun light therapy is expected to be a complementary alternative intervention for health management of the subjects with sleep disturbance and depression in climacteric women with menopausal symptoms.

8.
Korean J Women Health Nurs ; 20(2): 126-136, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37684788

RESUMO

PURPOSE: The purpose of this study was to examine the effects of aroma hand massage on anxiety and immune function in patients who had gynecology surgery under local anesthesia. METHODS: The research design was a nonequivalent control group with pre- and posttest design. Data were collected from June 5 to October 6, 2010. Participants included 20 patients in the aroma hand massage group, 20 patients in a hand massage group, and 20 in a control group. As an experimental treatment, hand massage was carried out following the hand massage protocol. Measures consisted of the State Trait Anxiety, Numeric Rating Scale (NRS) for anxiety, vital signs (systolic and diastolic blood pressure, pulse rate), and salivary cortisol for anxiety, and immunoglobulin A for immune function. RESULTS: Aroma hand massage and hand massage group showed lower levels in NRS for anxiety, systolic and diastolic blood pressure, and pulse rate (p<.001) compared to controls. No group differences were found for state anxiety, salivary cortisol and immunoglobulin A. CONCLUSION: The results indicate that aroma hand massage and hand massage are effective in reducing anxiety and can be complementary alternative interventions for women having gynecology surgery under local anesthesia.

9.
Korean J Parasitol ; 48(3): 267-70, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20877509

RESUMO

The principal objective of this study was to investigate the prevalence of toxoplasmosis in household and stray cats in Seoul, Republic of Korea. We collected blood samples from 72 stray and 80 household cats, and all samples were examined by ELISA and nested PCR. The overall positive rates of Toxoplasma gondii in stray cats were 38.9% (28/72), with 15.3% (11/72) in ELISA and 30.6% (22/72) in PCR. The positive rate in male stray cats was slightly higher than that of female stray cats. The highest positive rate of T. gondii infection was noted in Gangnam and Songpa populations in ELISA and in Gwangjin population in PCR. In household cats, however, we could not detect any specific antibodies or DNA for T. gondii. In conclusion, we recognized that the infection rate of toxoplasmosis in stray cats in Seoul was considerably high but household cats were free from infection.


Assuntos
Doenças do Gato/epidemiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Animais Domésticos/parasitologia , Anticorpos Antiprotozoários/sangue , Doenças do Gato/imunologia , Doenças do Gato/parasitologia , Gatos , Feminino , Masculino , Prevalência , República da Coreia/epidemiologia , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/parasitologia
10.
Korean J Parasitol ; 48(1): 9-13, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20333280

RESUMO

Pentatrichomonas hominis is considered a commensal protozoan in the large intestine of a number of mammalian hosts, such as cats, dogs, and non-human primates. The resulting infections, which can induce diarrhea, have been attributed to opportunistic overgrowth of P. hominis. This study was performed to confirm the P. hominis infection and its molecular characterization from the feces of puppies with diarrhea. Fecal samples were obtained from 14 German shepherd puppies with diarrhea over 1 week (7 females and 7 males, 2-9 months of age) residing on a dog farm in August 2007. Species-specific PCR assay identified P. hominis 18S rRNA genes in 3 of the 14 puppies (1 female and 2 males; 1 aged 2 months and 2 aged 9 months). This phylogenetic analysis established that P. hominis belonged to the 1st clade, which is comprised of Bos taurus and Felines.


Assuntos
Diarreia/veterinária , Doenças do Cão/parasitologia , Fezes/parasitologia , Infecções Protozoárias em Animais/parasitologia , Trichomonadida/classificação , Trichomonadida/isolamento & purificação , Animais , Sequência de Bases , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Diarreia/parasitologia , Cães , Feminino , Genes de RNAr , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , República da Coreia , Análise de Sequência de DNA , Homologia de Sequência , Trichomonadida/genética
11.
Korean J Parasitol ; 47(4): 413-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19967093

RESUMO

Genotyping of Toxoplasma gondii has been performed in 23 PCR positive blood samples from stray cats in Korea. We used 2 separate PCR-restriction fragment length polymorphism (RFLP) patterns of SAG2 gene, amplifying the 5' and 3' ends of the locus. The results revealed that all samples belonged to the type I clonal lineage. Although T. gondii organisms were not isolated from the samples, the results of the present study represent that stray cats with T. gondii infection should be seriously concerned in our environment. Adequate and continuous control programs of stray cats are needed to reduce the risk of transmission of T. gondii as a zoonotic infection threatening the public health.


Assuntos
Sangue/parasitologia , Doenças do Gato/parasitologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Animais , Antígenos de Protozoários/genética , Gatos , Análise por Conglomerados , Impressões Digitais de DNA/métodos , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Genótipo , Coreia (Geográfico) , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Proteínas de Protozoários/genética , Toxoplasma/isolamento & purificação
12.
Korean J Parasitol ; 46(3): 199-201, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18830064

RESUMO

Toxoplasma gondii is an obligate intracellular zoonotic protozoan with a worldwide distribution. It infects humans as well as a broad spectrum of vertebrate hosts. Cats and wild felidae play crucial roles in the epidemiology of toxoplasmosis. This study was performed to survey the prevalence of T. gondii infection among stray cats in the Gyeonggi-do, Republic of Korea. A total of 174 stray cat blood samples were collected from Gwacheon-si (n=20), Bucheon-si (82), and Yangju-si (72). Positive sera for T. gondii were identified in 14 samples (8.1%) exclusively via the latex agglutination test, 28 (16.1%) via ELISA, and 23 (13.2%) via PCR analysis. The overall infection rate of female stray cats (29.2%) presented as higher than that of male cats (24.0%). This study suggests that T. gondii is widespread in the stray cat population of Gyeonggi-do, Korea. It is urgently needed to control urban stray cat population and to reduce the risk of zoonotic transmission of toxoplasmosis to other animal hosts and humans.


Assuntos
Doenças do Gato/epidemiologia , Toxoplasmose Animal/epidemiologia , Animais , Doenças do Gato/parasitologia , Gatos , Feminino , Coreia (Geográfico)/epidemiologia , Masculino , Estudos Soroepidemiológicos
13.
Exp Biol Med (Maywood) ; 229(1): 65-71, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14709778

RESUMO

This study investigated whether high-salt intake influences atrial natriuretic peptide (ANP) system, atrial content, and release rate of ANP as well as receptor density in the kidney were measured in salt intake rats. Male Sprague-Dawley rats received either 0.9% or 2% salt in their drinking water for 10 days. The stretch-induced ANP secretion from isolated perfused non-beating left atria was accentuated, and the production of cGMP by ANP in renal cortical tissue membranes were pronounced in rats exposed to 0.9% salt for 10 days but not in rats exposed to 2% salt. The levels of ANP receptor density and expression in renal cortex were decreased in 2% salt intake rats but not in 0.9% salt intake rats. No significant differences in atrial and plasma concentrations of ANP and water balance were observed in both salt intakes. Therefore, these results suggest that atrial ANP secretion and its binding sites in the kidney may respond differently to ingested salt concentrations in rats.


Assuntos
Fator Natriurético Atrial/metabolismo , Receptores do Fator Natriurético Atrial/metabolismo , Cloreto de Sódio/farmacologia , Animais , Função Atrial/efeitos dos fármacos , Fator Natriurético Atrial/farmacologia , Pressão Sanguínea/efeitos dos fármacos , GMP Cíclico/biossíntese , Relação Dose-Resposta a Droga , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Espaço Extracelular/metabolismo , Córtex Renal/metabolismo , Glomérulos Renais/metabolismo , Medula Renal/metabolismo , Medula Renal/ultraestrutura , Masculino , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Cloreto de Sódio/urina , Fatores de Tempo , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
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