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1.
Nature ; 593(7857): 67-73, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953412

RESUMO

Transition metal (oxy)hydroxides are promising electrocatalysts for the oxygen evolution reaction1-3. The properties of these materials evolve dynamically and heterogeneously4 with applied voltage through ion insertion redox reactions, converting materials that are inactive under open circuit conditions into active electrocatalysts during operation5. The catalytic state is thus inherently far from equilibrium, which complicates its direct observation. Here, using a suite of correlative operando scanning probe and X-ray microscopy techniques, we establish a link between the oxygen evolution activity and the local operational chemical, physical and electronic nanoscale structure of single-crystalline ß-Co(OH)2 platelet particles. At pre-catalytic voltages, the particles swell to form an α-CoO2H1.5·0.5H2O-like structure-produced through hydroxide intercalation-in which the oxidation state of cobalt is +2.5. Upon increasing the voltage to drive oxygen evolution, interlayer water and protons de-intercalate to form contracted ß-CoOOH particles that contain Co3+ species. Although these transformations manifest heterogeneously through the bulk of the particles, the electrochemical current is primarily restricted to their edge facets. The observed Tafel behaviour is correlated with the local concentration of Co3+ at these reactive edge sites, demonstrating the link between bulk ion-insertion and surface catalytic activity.

2.
Analyst ; 149(9): 2542-2555, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38632960

RESUMO

Scanning electrochemical cell microscopy (SECCM) has emerged as a transformative technology for electrochemical materials characterisation and the study of single entities, garnering global adoption by numerous research groups. While details on the instrumentation and operational principles of SECCM are readily available, the growing need for practical guidelines, troubleshooting strategies, and a systematic overview of applications and trends has become increasingly evident. This tutorial review addresses this gap by offering a comprehensive guide to the practical application of SECCM. The review begins with a discussion of recent developments and trends in the application of SECCM, before providing systematic approaches to (and the associated troubleshooting associated with) instrumental set up, probe fabrication, substrate preparation and the deployment of environmental (e.g., atmosphere and humidity) control. Serving as an invaluable resource, this tutorial review aims to equip researchers and practitioners entering the field with a comprehensive guide to essential considerations for conducting successful SECCM experiments.

3.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34782464

RESUMO

Regulatory B cells (Breg cells) that secrete IL-10 or IL-35 (i35-Breg) play key roles in regulating immunity in tumor microenvironment or during autoimmune and infectious diseases. Thus, loss of Breg function is implicated in development of autoimmune diseases while aberrant elevation of Breg prevents sterilizing immunity, exacerbates infectious diseases, and promotes cancer metastasis. Breg cells identified thus far are largely antigen-specific and derive mainly from B2-lymphocyte lineage. Here, we describe an innate-like IL-27-producing natural regulatory B-1a cell (i27-Breg) in peritoneal cavity and human umbilical cord blood. i27-Bregs accumulate in CNS and lymphoid tissues during neuroinflammation and confers protection against CNS autoimmune disease. i27-Breg immunotherapy ameliorated encephalomyelitis and uveitis through up-regulation of inhibitory receptors (Lag3, PD-1), suppression of Th17/Th1 responses, and propagating inhibitory signals that convert conventional B cells to regulatory lymphocytes that secrete IL-10 and/or IL-35 in eye, brain, or spinal cord. Furthermore, i27-Breg proliferates in vivo and sustains IL-27 secretion in CNS and lymphoid tissues, a therapeutic advantage over administering biologics (IL-10, IL-35) that are rapidly cleared in vivo. Mutant mice lacking irf4 in B cells exhibit exaggerated increase of i27-Bregs with few i35-Bregs, while mice with loss of irf8 in B cells have abundance of i35-Bregs but defective in generating i27-Bregs, identifying IRF8/BATF and IRF4/BATF axis in skewing B cell differentiation toward i27-Breg and i35-Breg developmental programs, respectively. Consistent with its developmental origin, disease suppression by innate i27-Bregs is neither antigen-specific nor disease-specific, suggesting that i27-Breg would be effective immunotherapy for a wide spectrum of autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Doenças do Sistema Nervoso Central/imunologia , Interleucina-27/metabolismo , Doenças Neuroinflamatórias/imunologia , Animais , Linfócitos B Reguladores/imunologia , Diferenciação Celular , Encefalite , Fatores Reguladores de Interferon , Interleucina-10 , Camundongos , Uveíte/imunologia
4.
J Korean Med Sci ; 39(3): e27, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38258362

RESUMO

BACKGROUND: Coronary artery disease patients undergoing percutaneous coronary intervention (PCI) often exhibit reduced left ventricular ejection fraction (LVEF). However, the impact of LV dysfunction status in conjunction with platelet reactivity on clinical outcomes has not been previously investigated. METHODS: From the multicenter PTRG-DES (Platelet function and genoType-Related long-term prognosis in DES-treated patients) consortium, the patients were classified as preserved-EF (PEF: LVEF ≥ 50%) and reduced-EF (REF: LVEF< 5 0%) group by echocardiography. Platelet reactivity was measured using VerifyNow P2Y12 assay and high platelet reactivity (HPR) was defined as PRU ≥ 252. The major adverse cardiac and cerebrovascular events (MACCEs) were a composite of death, myocardial infarction, stent thrombosis and stroke at 5 years after PCI. Major bleeding was defined as Bleeding Academic Research Consortium bleeding types 3-5. RESULTS: A total of 13,160 patients from PTRG-DES, 9,319 (79.6%) patients with the results of both PRU and LVEF were analyzed. The incidence of MACCE and major bleeding was higher in REF group as compared with PEF group (MACCEs: hazard ratio [HR] 2.17, P < 0.001, 95% confidence interval [CI] 1.85-2.55; major bleeding: HR 1.78, P < 0.001, 95% CI 1.39-2.78). The highest rate of MACCEs was found in patients with REF and HPR, and the difference between the groups was statistically significant (HR 3.14 in REF(+)/HPR(+) vs. PEF(+)/HPR(-) group, P < 0.01, 95% CI 2.51-3.91). The frequency of major bleeding was not associated with the HPR in either group. CONCLUSION: LV dysfunction was associated with an increased incidence of MACCEs and major bleeding in patients who underwent PCI. The HPR status further exhibited significant increase of MACCEs in patients with LV dysfunction in a large, real-world registry. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04734028.


Assuntos
Stents Farmacológicos , Intervenção Coronária Percutânea , Disfunção Ventricular Esquerda , Humanos , Volume Sistólico , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Função Ventricular Esquerda , Hemorragia/etiologia
5.
Nurs Crit Care ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38516768

RESUMO

BACKGROUND: Delirium commonly occurs in paediatric patients with acute critical illness and negatively affects clinical outcomes. Variations in delirium knowledge levels and its management have been noted among nurses. AIMS: This study investigated nurses' experiences and knowledge levels regarding paediatric delirium. Additionally, we aimed to assess the gap between knowledge levels and practical experiences with paediatric delirium. STUDY DESIGN: This cross-sectional descriptive study conveniently sampled paediatric nurses from a university hospital in South Korea between September 2022 and March 2023. Nursing experiences with paediatric delirium and delirium knowledge levels were measured using structured survey questionnaires. Delirium knowledge was scored 0 to 47, and higher scores indicated higher levels of delirium-related knowledge. Data were analysed using descriptive statistics and presented as mean, standard deviation, frequency and percentage. RESULTS: A total of 127 paediatric nurses participated in this study; 40.2% had experience with 1-5 delirium cases in the previous year, and 86.6% (n = 110) had never used assessment tools for paediatric delirium assessment. The mean total delirium knowledge score was 34.45 ± 5.4; the mean scores of knowledge regarding aetiology, signs and symptoms and nursing management of delirium were 8.93 ± 1.31, 13.24 ± 2.81 and 12.3 ± 2.7, respectively. Interventions associated with a lower level of delirium-related knowledge and a lower performance rate included avoiding restraint use and maintaining hydration and electrolyte levels. Interventions associated with a higher level of delirium-related knowledge but a lower rate of performance comprised providing orientation, offering emotional support, allowing participants to stay with family members and administering medications to manage delirium. CONCLUSIONS: Although nurses working in paediatric units exhibited high rate of delirium nursing care, there was the gap between their delirium-related knowledge and practice. Nurses need to be aware of the insufficient part of delirium care, and paediatric delirium education should be reinforced. RELEVANCE TO CLINICAL PRACTICE: Preventing, assessing and systematically managing paediatric delirium is crucial, and considering the study results, delirium education among nurses is needed.

6.
Small ; 19(40): e2303442, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37269212

RESUMO

Understanding the solid electrolyte interphase (SEI) formation and (de)lithiation phenomena at silicon (Si) electrodes is key to improving the performance and lifetime of Si-based lithium-ion batteries. However, these processes remain somewhat elusive, and, in particular, the role of Si surface termination merits further consideration. Here, scanning electrochemical cell microscopy (SECCM) is used in a glovebox, followed by secondary ion mass spectrometry (SIMS) at identical locations to study the local electrochemical behavior and associated SEI formation, comparing Si (100) with a native oxide layer (SiOx /Si) and etched with hydrofluoric acid (HF-Si). HF-Si shows greater spatial electrochemical heterogeneity and inferior lithiation reversibility than SiOx /Si. This is attributed to a weakly passivating SEI and irreversible lithium trapping at the Si surface. Combinatorial screening of charge/discharge cycling by SECCM with co-located SIMS reveals SEI chemistry as a function of depth. While the SEI thickness is relatively independent of the cycle number, the chemistry - particularly in the intermediate layers - depends on the number of cycles, revealing the SEI to be dynamic during cycling. This work serves as a foundation for the use of correlative SECCM/SIMS as a powerful approach to gain fundamental insights on complex battery processes at the nano- and microscales.

7.
Acc Chem Res ; 55(3): 241-251, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35020363

RESUMO

ConspectusElectrochemical reduction of the greenhouse gas CO2 offers prospects for the sustainable generation of fuels and industrially useful chemicals when powered by renewable electricity. However, this electrochemical process requires the use of highly stable, selective, and active catalysts. The development of such catalysts should be based on a detailed kinetic and mechanistic understanding of the electrochemical CO2 reduction reaction (eCO2RR), ideally through the resolution of active catalytic sites in both time (i.e., temporally) and space (i.e., spatially). In this Account, we highlight two advanced spatiotemporal voltammetric techniques for electrocatalytic studies and describe the considerable insights they provide on the eCO2RR. First, Fourier transformed large-amplitude alternating current voltammetry (FT ac voltammetry), as applied by the Monash Electrochemistry Group, enables the resolution of rapid underlying electron-transfer processes in complex reactions, free from competing processes, such as the background double-layer charging current, slow catalytic reactions, and solvent/electrolyte electrolysis, which often mask conventional voltammetric measurements of the eCO2RR. Crucially, FT ac voltammetry allows details of the catalytically active sites or the rate-determining step to be revealed under catalytic turnover conditions. This is well illustrated in investigations of the eCO2RR catalyzed by Bi where formate is the main product. Second, developments in scanning electrochemical cell microscopy (SECCM) by the Warwick Electrochemistry and Interfaces Group provide powerful methods for obtaining high-resolution activity maps and potentiodynamic movies of the heterogeneous surface of a catalyst. For example, by coupling SECCM data with colocated microscopy from electron backscatter diffraction (EBSD) or atomic force microscopy, it is possible to develop compelling correlations of (precatalyst) structure-activity at the nanoscale level. This correlative electrochemical multimicroscopy strategy allows the catalytically more active region of a catalyst, such as the edge plane of two-dimensional materials and the grain boundaries between facets in a polycrystalline metal, to be highlighted. The attributes of SECCM-EBSD are well-illustrated by detailed studies of the eCO2RR on polycrystalline gold, where carbon monoxide is the main product. Comparing SECCM maps and movies with EBSD images of the same region reveals unambiguously that the eCO2RR is enhanced at surface-terminating dislocations, which accumulate at grain boundaries and slip bands. Both FT ac voltammetry and SECCM techniques greatly enhance our understanding of the eCO2RR, significantly boosting the electrochemical toolbox and the information available for the development and testing of theoretical models and rational catalyst design. In the future, it may be possible to further enhance insights provided by both techniques through their integration with in situ and in operando spectroscopy and microscopy methods.

8.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675135

RESUMO

Osteoporosis is evident in postmenopausal women and is an osteolytic disease characterized by bone loss that further increases the susceptibility to bone fractures and frailty. The use of complementary therapies to alleviate postmenopausal osteoporosis is fairly widespread among women. Edible Cirsium setidens contains various polyphenols of linarin, pectolinarin, and apigenin with antioxidant and hepatoprotective effects. This study aimed to determine whether Cirsium setidens water extracts (CSEs), the component linarin, and its aglycone acacetin blocked ovariectomy (OVX)-induced bone loss. This study employed OVX C57BL/6 female mice as a model for postmenopausal osteoporosis. CSEs, acacetin, or linarin was orally administrated to OVX mice at a dose of 20 mg/kg for 8 weeks. Surgical estrogen loss in mice for 8 weeks reduced bone mineral density (BMD) of mouse femur and serum 17ß-estradiol level and enhanced the serum receptor activator of NF-κB ligand/osteoprotegerin ratio with uterine atrophy. CSEs and linarin reversed such adverse effects and enhanced femoral BMD in OVX mice. Oral administration of CSEs and linarin attenuated tartrate-resistant acid phosphate activity and the induction of αvß3 integrins and proton suppliers in resorption lacunae in femoral bone tissue of OVX mice. In addition, CSEs and linarin curtailed the bone levels of cathepsin K and matrix metalloproteinase-9 responsible for osteoclastic bone resorption. On the other hand, CSEs and linarin enhanced the formation of trabecular bones in estrogen-deficient femur with increased induction of osteocalcin and osteopontin. Further, treatment with CSEs and linarin enhanced the collagen formation-responsive propeptide levels in the circulation along with the increase in the tissue non-specific alkaline phosphatase level in bone exposed to OVX. Supplementing CSEs, acacetin, or linarin to OVX mice elevated the formation of collagen fibers in OVX trabecular bone, evidenced using Picrosirius red staining. Accordingly, CSEs and linarin were effective in retarding osteoclastic bone resorption and promoting osteoblastic bone matrix mineralization under OVX conditions. Therefore, linarin, which is abundant in CSEs, may be a natural compound for targeting postmenopausal osteoporosis and pathological osteoresorptive disorders.


Assuntos
Reabsorção Óssea , Cirsium , Osteoporose Pós-Menopausa , Animais , Feminino , Camundongos , Densidade Óssea , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/etiologia , Colágeno/farmacologia , Estrogênios/farmacologia , Camundongos Endogâmicos C57BL , Osteoporose Pós-Menopausa/tratamento farmacológico , Ovariectomia/efeitos adversos
9.
Glia ; 70(3): 414-429, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34773273

RESUMO

Oligodendrocytes are the cells that myelinate axons and provide trophic support to neurons in the CNS. Their dysfunction has been associated with a group of disorders known as demyelinating diseases, such as multiple sclerosis. Oligodendrocytes are derived from oligodendrocyte precursor cells, which differentiate into premyelinating oligodendrocytes and eventually mature oligodendrocytes. The development and function of oligodendrocytes are tightly regulated by a variety of molecules, including laminin, a major protein of the extracellular matrix. Accumulating evidence suggests that laminin actively regulates every aspect of oligodendrocyte biology, including survival, migration, proliferation, differentiation, and myelination. How can laminin exert such diverse functions in oligodendrocytes? It is speculated that the distinct laminin isoforms, laminin receptors, and/or key signaling molecules expressed in oligodendrocytes at different developmental stages are the reasons. Understanding molecular targets and signaling pathways unique to each aspect of oligodendrocyte biology will enable more accurate manipulation of oligodendrocyte development and function, which may have implications in the therapies of demyelinating diseases. Here in this review, we first introduce oligodendrocyte biology, followed by the expression of laminin and laminin receptors in oligodendrocytes and other CNS cells. Next, the functions of laminin in oligodendrocyte biology, including survival, migration, proliferation, differentiation, and myelination, are discussed in detail. Last, key questions and challenges in the field are discussed. By providing a comprehensive review on laminin's roles in OL lineage cells, we hope to stimulate novel hypotheses and encourage new research in the field.


Assuntos
Bainha de Mielina , Células Precursoras de Oligodendrócitos , Diferenciação Celular/fisiologia , Laminina/metabolismo , Bainha de Mielina/metabolismo , Neurogênese , Oligodendroglia/metabolismo
10.
Anal Chem ; 94(11): 4729-4736, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35255211

RESUMO

Indium tin oxide (ITO) is a popular electrode choice, with diverse applications in (photo)electrocatalysis, organic photovoltaics, spectroelectrochemistry and sensing, and as a support for cell biology studies. Although ITO surfaces exhibit heterogeneous local electrical conductivity, little is known as to how this translates to electrochemistry at the same scale. This work investigates nanoscale electrochemistry at ITO electrodes using high-resolution scanning electrochemical cell microscopy (SECCM). The nominally fast outer-sphere one-electron oxidation of 1,1'-ferrocenedimethanol (FcDM) is used as an electron transfer (ET) kinetic marker to reveal the charge transfer properties of the ITO/electrolyte interface. SECCM measures spatially resolved linear sweep voltammetry at an array of points across the ITO surface, with the topography measured synchronously. Presentation of SECCM data as current maps as a function of potential reveals that, while the entire surface of ITO is electroactive, the ET activity is highly spatially heterogeneous. Kinetic parameters (standard rate constant, k0, and transfer coefficient, α) for FcDM0/+ are assigned from 7200 measurements at sites across the ITO surface using finite element method modeling. Differences of 3 orders of magnitude in k0 are revealed, and the average k0 is about 20 times larger than that measured at the macroscale. This is attributed to macroscale ET being largely limited by lateral conductivity of the ITO electrode under electrochemical operation, rather than ET kinetics at the ITO/electrolyte interface, as measured by SECCM. This study further demonstrates the considerable power of SECCM for direct nanoscale characterization of electrochemical processes at complex electrode surfaces.


Assuntos
Compostos de Estanho , Eletroquímica , Eletrodos , Oxirredução , Compostos de Estanho/química
11.
Nat Mater ; 20(7): 1000-1006, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33737727

RESUMO

Understanding how the bulk structure of a material affects catalysis on its surface is critical to the development of actionable catalyst design principles. Bulk defects have been shown to affect electrocatalytic materials that are important for energy conversion systems, but the structural origins of these effects have not been fully elucidated. Here we use a combination of high-resolution scanning electrochemical cell microscopy and electron backscatter diffraction to visualize the potential-dependent electrocatalytic carbon dioxide [Formula: see text] electroreduction and hydrogen [Formula: see text] evolution activity on Au electrodes and probe the effects of bulk defects. Comparing colocated activity maps and videos to the underlying microstructure and lattice deformation supports a model in which CO2 electroreduction is selectively enhanced by surface-terminating dislocations, which can accumulate at grain boundaries and slip bands. Our results suggest that the deliberate introduction of dislocations into materials is a promising strategy for improving catalytic properties.

12.
J Pathol ; 253(1): 55-67, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918742

RESUMO

Nonalcoholic fatty liver disease is a chronic condition involving steatosis, steatohepatitis and fibrosis, and its progression remains unclear. Although the tetraspanin transmembrane 4 L six family member 5 (TM4SF5) is involved in hepatic fibrosis and cancer, its role in nonalcoholic steatohepatitis (NASH) progression is unknown. We investigated the contribution of TM4SF5 to liver pathology using transgenic and KO mice, diet- or drug-treated mice, in vitro primary cells, and in human tissue. TM4SF5-overexpressing mice exhibited nonalcoholic steatosis and NASH in an age-dependent manner. Initially, TM4SF5-positive hepatocytes and liver tissue exhibited lipid accumulation, decreased Sirtuin 1 (SIRT1), increased sterol regulatory-element binding proteins (SREBPs) and inactive STAT3 via suppressor of cytokine signaling (SOCS)1/3 upregulation. In older mice, TM4SF5 promoted inflammatory factor induction, SIRT1 expression and STAT3 activity, but did not change SOCS or SREBP levels, leading to active STAT3-mediated ECM production for NASH progression. A TM4SF5-associated increase in chemokines promoted SIRT1 expression and progression to NASH with fibrosis. Suppression of the chemokine CCL20 reduced immune cell infiltration and ECM production. Liver tissue from high-fat diet- or CCl4 -treated mice and human patients exhibited TM4SF5-dependent steatotic or steatohepatitic livers with links between TM4SF5-mediated SIRT1 modulation and SREBP or SOCS/STAT3 signaling axes. TM4SF5-mediated STAT3 activation in fibrotic NASH livers increased collagen I and laminin γ2. Both collagen I α1 and laminin γ2 suppression resulted in reduced SIRT1 and active STAT3, but no change in SREBP1 or SOCS, and abolished CCl4 -mediated mouse liver damage. TM4SF5-mediated signaling pathways that involve SIRT1, SREBPs and SOCS/STAT3 promoted progression to NASH. Therefore, TM4SF5 and its downstream effectors may be promising therapeutic targets to treat nonalcoholic fatty liver disease. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Matriz Extracelular/enzimologia , Metabolismo dos Lipídeos , Cirrose Hepática Experimental/enzimologia , Fígado/enzimologia , Proteínas de Membrana/metabolismo , Hepatopatia Gordurosa não Alcoólica/enzimologia , Sirtuína 1/metabolismo , Animais , Tetracloreto de Carbono , Linhagem Celular Tumoral , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Dieta Hiperlipídica , Progressão da Doença , Matriz Extracelular/patologia , Humanos , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/patologia , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais
13.
J Pediatr Nurs ; 65: e93-e98, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422366

RESUMO

PURPOSE: Depressive symptoms among adolescents are a major concern for increased risk of adverse health condition outcomes later in life. Specifically, previous studies have reported that multicultural adolescents experience more depressive symptoms than non-multicultural ones. Using the Korean Children and Youth Panel Survey, this study examined the relationships between ego-resilience, social support, and depression among multicultural adolescents in South Korea, as well as the moderating effect of social support on the association between ego-resilience and depression. DESIGN AND METHODS: A total of 1500 multicultural adolescents were included in the analyses, where generalized estimating equation models were employed. RESULTS: Depression scores increased slightly from 2012 to 2015. Higher levels of ego-resilience, family support, and friend support were associated with lower levels of depression, while teacher support was not a significant predictor. The moderating effect of friends and family support on the association between ego-resilience and depression was not statistically significant. CONCLUSIONS: To reduce the level of depression among multicultural adolescents, future research should develop interventions that enhance ego-resilience ability, as well as necessary social systems that strengthen family and friend support. PRACTICE IMPLICATIONS: Supportive interventions, such as enhancing ego-resilience to reduce depression should be provided to multicultural adolescents. It is recommended to include family and friends to develop effective intervention programs for multicultural adolescents who are suffering from depression.


Assuntos
Amigos , Apoio Social , Adolescente , Criança , Ego , Humanos , República da Coreia , Inquéritos e Questionários
14.
Int J Mol Sci ; 23(15)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35897732

RESUMO

Interleukin-27 is constitutively secreted by microglia in the retina or brain, and upregulation of IL-27 during neuroinflammation suppresses encephalomyelitis and autoimmune uveitis. However, while IL-35 is structurally and functionally similar to IL-27, the intrinsic roles of IL-35 in CNS tissues are unknown. Thus, we generated IL-35/YFP-knock-in reporter mice (p35-KI) and demonstrated that photoreceptor neurons constitutively secrete IL-35, which might protect the retina from persistent low-grade inflammation that can impair photoreceptor functions. Furthermore, the p35-KI mouse, which is hemizygous at the il12a locus, develops more severe uveitis because of reduced IL-35 expression. Interestingly, onset and exacerbation of uveitis in p35-KI mice caused by extravasation of proinflammatory Th1/Th17 lymphocytes into the retina were preceded by a dramatic decrease of IL-35, attributable to massive death of photoreceptor cells. Thus, while inflammation-induced death of photoreceptors and loss of protective effects of IL-35 exacerbated uveitis, our data also suggest that constitutive production of IL-35 in the retina might have housekeeping functions that promote sterilization immunity in the neuroretina and maintain ocular immune privilege.


Assuntos
Doenças Autoimunes , Interleucinas , Uveíte , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Privilégio Imunológico , Inflamação/metabolismo , Interleucina-27/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Fotorreceptoras/metabolismo , Retina/metabolismo , Células Th17 , Uveíte/metabolismo
15.
J Nurs Manag ; 30(7): 2811-2824, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35593655

RESUMO

AIMS: This study aimed to estimate the overall presenteeism prevalence in the nursing workforce. BACKGROUND: Nurses are more prone to presenteeism, which is associated with adverse outcomes for both nurses and patients. However, comprehensive information on the global prevalence of presenteeism in nursing workforce is lacking. EVALUATION: Seven databases were systematically searched without year or language restrictions in July 2021. Studies that reported the prevalence rate of presenteeism among nurses were included. A meta-analysis was performed using a random-effects model. KEY ISSUES: A total of 28 studies from 14 countries were included. The overall pooled estimate of presenteeism prevalence among nursing workforce was 49.2% (95% CI: 0.411, 0.574). Subgroup analyses showed that the prevalence of presenteeism was higher when the reporting time frame was >1 month and <1 year compared with ≤1 month or ≥1 year. CONCLUSION: The results of this meta-analysis showed the substantial prevalence of presenteeism in the nursing workforce with variations across different reporting time frames. IMPLICATION FOR NURSING MANAGEMENT: The findings can be used to support nurse managers, administrators and policymakers in recognizing the prevalence of presenteeism and developing relevant prevention strategies against presenteeism among global nursing workforce.


Assuntos
Recursos Humanos de Enfermagem , Presenteísmo , Humanos , Prevalência , Recursos Humanos
16.
Medicina (Kaunas) ; 58(9)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36143949

RESUMO

BACKGROUND AND OBJECTIVES: Bacterial antibiotics have had several side effects. Therefore, interest in natural substances with less side effects is increasing these days. Paeonia lactiflora, the root of Paeonia lactiflora, is used as a raw material for medicines. In this study, we investigated the antibacterial effect and the cytotoxicity of Paeonia lactiflora extract. MATERIALS AND METHODS: For cytotoxicity, MTT analysis according to ISO 10993-5 was performed. The antibacterial test of the Paeonia lactiflora was determined from bacterial viability, Inhibition zone test, CFU (colony forming unit) and SEM (scanning electron microscope). To confirm the antibacterial component of Paeonia lactiflora, the content of flavonoids and polyphenols was analyzed. RESULTS: Our results showed that Paeonia lactiflora extract contained flavonoids and polyphenols, which exhibited antimicrobial activity against Streptococcus mutans (S. mutans) and Candida albicans (C. ablicans). Further, the cytotoxicity of Paeonia lactiflora extract was low. CONCLUSIONS: We believe that our study makes a significant contribution to the literature because it demonstrates that Paeonia lactiflora extract can be used as an antibiotic.


Assuntos
Anti-Infecciosos , Antineoplásicos , Paeonia , Antibacterianos/farmacologia , Humanos , Metanol , Extratos Vegetais/farmacologia , Polifenóis
17.
Medicina (Kaunas) ; 58(11)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36363513

RESUMO

Background and Objectives The antimicrobial efficacy of a nonthermal atmospheric-pressure plasma jet (NAPPJ) on dental impression materials was investigated. Materials and Methods Type 3 polyvinyl siloxane was used as the impression material, and air and nitrogen NAPPJ were applied. The antibacterial effect of the NAPPJ was measured using the number of colony-forming units (CFUs) and scanning electron microscopy (SEM) images of Streptococcus mutans. Surface chemical characteristics of the impression material were examined using X-ray photoelectron spectroscopy (XPS) and contact angle measurement. Additionally, physical properties were analyzed through surface roughness measurement, detail reproduction, and strain-in-compression test. Results Compared with the control group, the plasma treatment group showed ruptured bacteria membranes, destroyed bacteria structures, a significant reduction in the number of CFUs, and a significantly reduced contact angle. Further, XPS analysis showed that their surface was significantly richer in hydroxyl groups. The surface roughness, detail reproduction, and strain-in-compression results indicated no significant differences between the plasma treatment and control groups. NAPPJ treatment could remove bacteria from polyvinyl siloxane dental impression materials without changing the surface's physical properties. Conclusion Therefore, it is considered a promising method for disinfection.


Assuntos
Gases em Plasma , Humanos , Gases em Plasma/farmacologia , Gases em Plasma/química , Propriedades de Superfície , Teste de Materiais , Materiais para Moldagem Odontológica
18.
Cardiovasc Ultrasound ; 19(1): 20, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090472

RESUMO

AIMS: The purpose of this study were to identify the usefulness of screening for PFO using agitated saline echocardiography (ASE) and characteristics and prognosis of patients with suggestive of patent foramen ovale (PFO). METHODS: Three hundred three patients (mean age, 53 ± 9 years; 199 [66%] men) admitted with acute stroke or suspicion of stroke were included. Patients were classified into those with and without right-to-left shunt (RLS) according to the ASE results (positive ASE [n = 92] vs. negative ASE [n = 211]). Fifty-one out of ninety-two patients with positive ASE and twenty-one out of two hundred eleven patients with negative ASE underwent TEE with ASE to confirm PFO. RESULTS: Ninety-two were positive for ASE and thirty-six of the fifty-one patients who underwent TEE were confirmed as having PFO. Of the patients with RLS grade 1, 50% were diagnosed with PFO and all patients with RLS grade ≥ 2 were diagnosed with PFO. All patients with negative ASE had no PFO (sensitivity of 100% and specificity of 58%). Patients with positive ASE were younger, had a lower body mass, and a lower prevalence of hypertension. The positive ASE patients had a higher mean S' velocity and better diastolic function. Four of ninety-one patients with positive ASE and thirteen of one hundred seventy-seven showed recurrence of stroke and suspicion of stroke. CONCLUSION: Transthoracic ASE is a good method to screen for PFO. Patients with suggestive of PFO had lower risk factors, less atherosclerosis, and better cardiac performance.


Assuntos
Forame Oval Patente , AVC Isquêmico , Acidente Vascular Cerebral , Adulto , Ecocardiografia , Ecocardiografia Transesofagiana , Forame Oval Patente/diagnóstico , Forame Oval Patente/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia
19.
J Nurs Scholarsh ; 53(1): 126-136, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33205904

RESUMO

PURPOSE: This study aimed to examine the effects of work environments and occupational fatigue on care left undone in rotating shift nurses, and to identify the indirect (mediation) effect of work environments on care left undone through nurses' occupational fatigue in South Korean acute care hospitals. DESIGN: This study employed a cross-sectional design using an online survey to collect data from 488 rotating shift nurses of acute care hospitals in Korea between November and December 2018. METHODS: A mobile schedule management application for shift nurses was used to advertise the study and to send a link to the online survey. The survey included questions on the nurses' work environment characteristics, care left undone activities, and the Korean version of the Occupational Fatigue Exhaustion/Recovery scale. Poisson regression was used to explore the relationships among work environments, occupational fatigue, and care left undone. Hayes' Model 4 and a bootstrapping analysis were used to identify the mediating effect of occupational fatigue on the relationship between work environments and care left undone. FINDINGS: The average number of tasks left undone was 3.45 (SD = 2.19). The higher the acute and chronic fatigue levels noted among nurses, the higher were the occurrences of care left undone. Conversely, the higher the intershift recovery level, the lower were the occurrences of care left undone. The results showed a positive relationship between care left undone and overtime hours and the number of patients per nurse. Moreover, nurses' occupational fatigue mediated the relationship between work environments and care left undone. Night shifts per month and the number of consecutive days off had an indirect effect on care left undone through occupational fatigue. CONCLUSIONS: High levels of occupational fatigue and poor intershift recovery among nurses can lead to care left undone. Nurses' occupational fatigue mediates the effect of work environment on care left undone. CLINICAL RELEVANCE: It is crucial for healthcare administrators and leaders to develop policies and mandatory regulations to facilitate better working conditions for nurses, consequently reducing their occupational fatigue and decreasing the occurrence of care left undone in acute care hospitals.


Assuntos
Fadiga/epidemiologia , Cuidados de Enfermagem/normas , Recursos Humanos de Enfermagem Hospitalar/psicologia , Doenças Profissionais/epidemiologia , Jornada de Trabalho em Turnos/psicologia , Local de Trabalho , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Recursos Humanos de Enfermagem Hospitalar/estatística & dados numéricos , República da Coreia/epidemiologia , Inquéritos e Questionários
20.
Nano Lett ; 20(3): 2012-2019, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32053383

RESUMO

The fine-tuning of molecular transport is a ubiquitous problem of single-molecule methods. The latter is evident even in powerful single-molecule techniques such as nanopore sensing, where the quest for resolving more detailed biomolecular features is often limited by insufficient control of the dynamics of individual molecules within the detection volume of the nanopore. In this work, we introduce and characterize a reconfigurable multi-nanopore architecture that enables additional channels to manipulate the dynamics of DNA molecules in a nanopore. We show that the fabrication process of this device, consisting of four adjacent, individually addressable nanopores located at the tip of a quartz nanopipette, is fast and highly reproducible. By individually tuning the electric field across each nanopore, these devices can operate in several unique cooperative detection modes that allow moving, sensing, and trapping of DNA molecules with high efficiency and increased temporal resolution.


Assuntos
Técnicas Biossensoriais , DNA/química , Nanoporos
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