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1.
Nano Lett ; 24(21): 6417-6424, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38710072

RESUMO

The functional properties of complex oxides, including magnetism and ferroelectricity, are closely linked to subtle structural distortions. Ultrafast optical excitations provide the means to manipulate structural features and ultimately to affect the functional properties of complex oxides with picosecond-scale precision. We report that the lattice expansion of multiferroic BiFeO3 following above-bandgap optical excitation leads to distortion of the oxygen octahedral rotation (OOR) pattern. The continuous coupling between OOR and strain was probed using time-resolved X-ray free-electron laser diffraction with femtosecond time resolution. Density functional theory calculations predict a relationship between the OOR and the elastic strain consistent with the experiment, demonstrating a route to employing this approach in a wider range of systems. Ultrafast control of the functional properties of BiFeO3 thin films is enabled by this approach because the OOR phenomena are related to ferroelectricity, and via the Fe-O-Fe bond angles, the superexchange interaction between Fe atoms.

2.
Int Arch Occup Environ Health ; 97(5): 537-543, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38564018

RESUMO

PURPOSE: This study aimed to reveal the relationship of the days of experiencing sickness presentism and depressive symptoms among Korean workers. Sickness presenteeism which defined as the act of going to work despite being feeling unhealthy triggers various adverse effects on mental health, including increased risks of depression. Furthermore, Sickness presenteeism is a major social issue causing substantial socioeconomic costs. METHODS: The data of 25120 participants from sixth Korean Working Condition Survey was utilized in this cross-sectional study. Sickness presenteeism was defined using a self-reported questionnaire and depressive symptoms were assessed by WHO well-being index. Multivariate logistic regression analysis was conducted to calculate the odd ratios for depressive symptoms regarding the number of days experiencing sickness presenteeism. We calculated odds ratios (ORs) and 95% confidence interval (95% CI) for depressive symptoms after categorizing participants into three groups based on the duration of experiencing sickness presenteeism, using cut-off values of 3 and 5 days. RESULTS: Workers who have experienced sickness presenteeism for more than 5 days were at highest risk for depressive symptoms than referent group (OR 2.87; 95% CI 2.17-3.76 in male, OR 3.86; 95% CI 3.02-4.91 in female). Furthermore, there was a trend of increasing risk for depressive symptom as the duration of experiencing sickness presenteeism extended. CONCLUSION: This study presents the association between experiencing sickness presenteeism in the previous 12 months and depressive symptoms. Based on the results, we provide individual and organizational strategies of reducing sickness presenteeism. Also, screening for workers who have experienced sickness presenteeism are needed to ensure good mental health.


Assuntos
Depressão , Presenteísmo , Humanos , Masculino , Feminino , Presenteísmo/estatística & dados numéricos , Estudos Transversais , Depressão/epidemiologia , Adulto , República da Coreia/epidemiologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Licença Médica/estatística & dados numéricos , Adulto Jovem , Fatores de Risco , Condições de Trabalho
3.
Nano Lett ; 23(19): 8914-8922, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37722002

RESUMO

Transition-metal dichalcogenides (TMDs) and metal halide perovskites (MHPs) have been investigated for various applications, owing to their unique physical properties and excellent optoelectronic functionalities. TMD monolayers synthesized via chemical vapor deposition (CVD), which are advantageous for large-area synthesis, exhibit low mobility and prominent hysteresis in the electrical signals of field-effect transistors (FETs) because of their native defects. In this study, we demonstrate an increase in electrical mobility by ∼170 times and reduced hysteresis in the current-bias curves of MoS2 FETs hybridized with CsPbBr3 for charge transfer doping, which is implemented via solution-based CsPbBr3-nanocluster precipitation on CVD-grown MoS2 monolayer FETs. Electrons injected from CsPbBr3 into MoS2 induce heavy n-doping and heal point defects in the MoS2 channel layer, thus significantly increasing mobility and reducing hysteresis in the hybrid FETs. Our results provide a foundation for improving the reliability and performance of TMD-based FETs by hybridizing them with solution-based perovskites.

4.
Small ; 19(1): e2204617, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36354165

RESUMO

A variety of wound healing platforms have been proposed to alleviate the hypoxic condition and/or to modulate the immune responses for the treatment of chronic wounds in diabetes. However, these platforms with the passive diffusion of therapeutic agents through the blood clot result in the relatively low delivery efficiency into the deep wound site. Here, a microalgae-based biohybrid microrobot for accelerated diabetic wound healing is developed. The biohybrid microrobot autonomously moves at velocity of 33.3 µm s-1 and generates oxygen for the alleviation of hypoxic condition. In addition, the microrobot efficiently bound with inflammatory chemokines of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) for modulating the immune responses. The enhanced penetration of microrobot is corroborated by measuring fibrin clots in biomimetic wound using microfluidic devices and the enhanced retention of microrobot is confirmed in the real wounded mouse skin tissue. After deposition on the chronic wound in diabetic mice without wound dressing, the wounds treated with microrobots are completely healed after 9 days with the significant decrease of inflammatory cytokines below 31% of the control level and the upregulated angiogenesis above 20 times of CD31+ cells. These results confirm the feasibility of microrobots as a next-generation platform for diabetic wound healing.


Assuntos
Diabetes Mellitus Experimental , Microalgas , Camundongos , Animais , Microalgas/metabolismo , Cicatrização/fisiologia , Pele/metabolismo , Citocinas/metabolismo
5.
Nano Lett ; 22(11): 4294-4300, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35612522

RESUMO

Optical excitation leads to ultrafast stress generation in the prototypical multiferroic BiFeO3. The time scales of stress generation are set by the dynamics of the population of excited electronic states and the coupling of the electronic configuration to the structure. X-ray free-electron laser diffraction reveals high-wavevector subpicosecond-time scale stress generation following ultraviolet excitation of a BiFeO3 thin film. Stress generation includes a fast component with a 1/e rise time with an upper limit of 300 fs and longer-rise time components extending to 1.5 ps. The contributions of the fast and delayed components vary as a function of optical fluence, with a reduced a fast-component contribution at high fluence. The results provide insight into stress-generation mechanisms linked to the population of excited electrons and point to new directions in the application of nanoscale multiferroics and related ferroic complex oxides. The fast component of the stress indicates that structural parameters and properties of ferroelectric thin film materials can be optically modulated with 3 dB bandwidths of at least 0.5 THz.

6.
Biochem Biophys Res Commun ; 592: 119-124, 2022 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-35051687

RESUMO

Several natural substances including protein produce sweet taste. Brazzein, derived from the plant Pentadipladra brazzeana, is one of the sweet proteins that bind to the taste receptor with stronger sweetness than sugar. Mutations of this protein affect its flavour, yielding higher sweetness in D29K and lower sweetness in R43A. To elucidate its sweet mechanism in the taste receptor, we determined the structures of two variants, D29K and R43A, to a resolution of 1.5 Å and 1.3 Å, respectively. Structures of the brazzein exhibit two α-helix and three ß-sheets connected by four disulfide bonds with a significantly altered electrostatic distribution on the surface. Using the high-resolution structure data and models of the taste receptors T1R2 and T1R3 in the AlphaFold Protein Structure Database, we performed a docking calculation on the receptors and report that brazzein is bound between the two cysteine rich domains (CRDs) of the heterodimer protein complex. Substitution to lysine in D29K resulted in an increased number of hydrogen bonds in the T1R2 receptor, while substitution to alanine in R43A ablated a polar interaction in the T1R3 receptor. The significantly altered interaction of the variants at the interface is consistent with a change of the sweetness. The high-resolution structure and the docking model in this study may provide a structural basis to understand the flavour mechanism induced by the sweet protein.


Assuntos
Cristalografia por Raios X , Simulação de Acoplamento Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Ligação de Hidrogênio , Ligação Proteica , Multimerização Proteica , Receptores Acoplados a Proteínas G/química , Paladar
7.
Biochem Biophys Res Commun ; 593: 79-83, 2022 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-35063773

RESUMO

mCardinal2 is a red fluorescent protein developed through the designs of mKate, mNeptune and mCardinal. Fluorescence spectrums of mCardinal2 and its five mutants (T143C, T143G, C158A, C158D and M160E) were measured with their quantum yields. C158A and C158D increased brightness with slight changes in fluorescence spectrums while T143C, T143G and M160E decreased brightness with blue shift in fluorescence spectrums, which resulted in green, cyan and green fluorescent proteins respectively. Crystal structures of all six variants were analyzed and compared together with those of mKate, LSS-mKate1, LSS-mKate2 and mCardinal. Around the Cα-Cß bond of Tyr64 in the MYG chromophores, only C158A and C158D were in the trans conformation while all others were mostly in the cis conformation. Blue-shift brightness-decreased variants (T143C, T143G and M160E) showed the diminished hydrogen bonds while large-Stoke-shift brightness-increased variant C158D showed the enhanced hydrogen bonds around the chromophore.


Assuntos
Fluorescência , Proteínas Luminescentes/química , Proteínas Luminescentes/metabolismo , Mutação , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Proteínas Luminescentes/genética , Modelos Moleculares , Conformação Proteica , Engenharia de Proteínas , Proteína Vermelha Fluorescente
8.
Biochem Biophys Res Commun ; 635: 169-178, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36274367

RESUMO

OBJECTIVE: There are no effective treatments for relieving neuronal dysfunction after mild traumatic brain injury (TBI). Here, we evaluated therapeutic efficacy of human embryonic stem cell-derived cerebral organoids (hCOs) in a mild TBI model, in terms of repair of damaged cortical regions, neurogenesis, and improved cognitive function. METHODS: Male C57BL/6 J mice were randomly divided into sham-operated, mild TBI, and mild TBI with hCO groups. hCOs cultured at 8 weeks were used for transplantation. Mice were sacrificed at 7 and 14 days after transplantation followed by immunofluorescence staining, cytokine profile microarray, and novel object recognition test. RESULTS: 8W-hCOs transplantation significantly reduced neuronal cell death, recovered microvessel density, and promoted neurogenesis in the ipsilateral subventricular zone and dentate gyrus of hippocampus after mild TBI. In addition, increased angiogenesis into the engrafted hCOs was observed. Microarray results of hCOs revealed neuronal differentiation potential and higher expression of early brain development proteins associated with neurogenesis, angiogenesis and extracellular matrix remodeling. Ultimately, 8W-hCO transplantation resulted in reconstruction of damaged cortex and improvement in cognitive function after mild TBI. CONCLUSION: hCO transplantation may be feasible for treating mild TBI-related neuronal dysfunction via reconstruction of damaged cortex and neurogenesis in the hippocampus.


Assuntos
Concussão Encefálica , Lesões Encefálicas Traumáticas , Células-Tronco Embrionárias Humanas , Animais , Humanos , Masculino , Camundongos , Concussão Encefálica/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Neurogênese/fisiologia , Organoides
9.
Dysphagia ; 37(1): 183-191, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33586044

RESUMO

This study aimed to measure the validity and reliability of the Korean version of the Dysphagia Handicap Index (K-DHI) and evaluate its diagnostic efficacy for predicting aspiration. We enrolled 104 patients with dysphagia symptoms (D group) and 88 controls (ND group). Among controls, there were 43 patients without dysphagia symptoms (ND patient group). All subjects completed the K-DHI survey. The D and ND group patients underwent the Gugging Swallowing Screen (GUSS) and videofluoroscopic swallowing study (VFSS). Two weeks later, the D group completed the second session of the K-DHI survey. The internal consistency of the K-DHI was good to excellent (Cronbach's α: 0.79-0.95). The test-retest reliability of the K-DHI survey was also high (interclass correlation coefficient = 0.88). There were moderate correlations between the K-DHI and GUSS (r = - 0.65, p < 0.001) as well as findings of VFSS-videofluoroscopic dysphagia scale (r = 0.55, p < 0.001) and American Speech-Language-Hearing Association National Outcome Measurement System swallowing scale (r = - 0.55, p < 0.001). For predicting aspiration, the K-DHI cutoff value was 11 (sensitivity, 0.82; specificity, 0.72; positive predictive value, 0.34; and negative predictive value, 0.96). K-DHI ≥ 11 [odds ratio (OR), 6.43; 95% Confidence Interval (CI) (1.87-22.16); p = 0.003] and GUSS ≤ 15 [OR 4.73; 95% CI (1.59-14.07); p = 0.005] were independent risk factors for aspiration on VFSS. The K-DHI is a reliable and valid self-reporting instrument for evaluating patient's quality of life associated with dysphagia among the Korean language population. It is also useful for the screening of aspiration.


Assuntos
Transtornos de Deglutição , Deglutição , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Humanos , Qualidade de Vida , Reprodutibilidade dos Testes , República da Coreia , Inquéritos e Questionários
10.
Int J Mol Sci ; 23(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35897746

RESUMO

Exposure to particulate matter (PM) has been linked with the severity of various diseases. To date, there is no study on the relationship between PM exposure and tendon healing. Open Achilles tenotomy of 20 rats was performed. The animals were divided into two groups according to exposure to PM: a PM group and a non-PM group. After 6 weeks of PM exposure, the harvest and investigations of lungs, blood samples, and Achilles tendons were performed. Compared to the non-PM group, the white blood cell count and tumor necrosis factor-alpha expression in the PM group were significantly higher. The Achilles tendons in PM group showed significantly increased inflammatory outcomes. A TEM analysis showed reduced collagen fibrils in the PM group. A biomechanical analysis demonstrated that the load to failure value was lower in the PM group. An upregulation of the gene encoding cyclic AMP response element-binding protein (CREB) was detected in the PM group by an integrated analysis of DNA methylation and RNA sequencing data, as confirmed via a Western blot analysis showing significantly elevated levels of phosphorylated CREB. In summary, PM exposure caused a deleterious effect on tendon healing. The molecular data indicate that the action mechanism of PM may be associated with upregulated CREB signaling.


Assuntos
Tendão do Calcâneo , Material Particulado , Tendão do Calcâneo/metabolismo , Animais , Fenômenos Biomecânicos , Metilação de DNA , Material Particulado/toxicidade , RNA/metabolismo , Ratos , Ratos Sprague-Dawley , Análise de Sequência de RNA
11.
Biochem Biophys Res Commun ; 557: 33-39, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33862457

RESUMO

Cell death and differentiation are closely related at the molecular level. Differentiation of skeletal muscle cells attenuates susceptibility to apoptosis. Necroptosis has recently been recognized as a form of regulated cell death but its role in myogenesis has not been studied. This study aimed to compare the sensitivity to TNF-induced necroptosis in skeletal muscle at the undifferentiated (myoblasts) and differentiated (myotubes) stages. Surprisingly, our results showed that TNF-induced necroptosis was blunted during myoblast differentiation. Moreover, our data revealed that the key molecules involved in necroptosis, including receptor-interacting serine/threonine protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like protein (MLKL), were significantly down-regulated during myogenic differentiation, resulting in suppression of necroptosis signal transduction in differentiated myotubes. In addition, RIPK1, RIPK3, and MLKL expression levels were significantly lower in the skeletal muscle of adult mice than in newborn mice, suggesting that the susceptibility to necroptosis might be attenuated in differentiated muscle tissue. In conclusion, this study revealed that expression of key molecules involved in necroptosis is down-regulated during muscle differentiation, which results in the differentiation of muscles becoming insensitive to necroptotic cell death.


Assuntos
Desenvolvimento Muscular/fisiologia , Necroptose/fisiologia , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Regulação para Baixo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Fosforilação , Transdução de Sinais
12.
Int Urogynecol J ; 32(6): 1481-1486, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32358625

RESUMO

INTRODUCTION AND HYPOTHESIS: The aim of this study was to report the long-term outcomes after sacrocolpopexy (SCP) with or without transobturator tape (TOT). METHODS: We conducted a planned secondary analysis of a prospective, observational study comparing urinary outcomes in women who underwent SCP with or without TOT based on the results of a prolapse-reduction stress test. Patients were enrolled between November 2008 and December 2011 and were followed up 5 years after surgery. The primary outcomes were 5-year success rates for stress urinary incontinence (SUI) and pelvic organ prolapse (POP) estimated using the Kaplan-Meier method. SUI success was defined as a negative cough stress test, no bothersome SUI symptoms, and no additional anti-incontinence surgery. POP success was defined as no vaginal bulge symptoms, no apical descent greater than one-third of the total vaginal length or anterior or posterior vaginal wall prolapse beyond the hymen, and no retreatment for prolapse. RESULTS: Of 240 women enrolled, 175 (73%) completed 5 years of follow-up. The estimated SUI success rate was 91.1% in the TOT group and 56.5% in the no TOT group (difference, 34.6%; 95% confidence interval, 24.1 to 45.1). The estimated POP success rate was 90.0% in the TOT group and 92.9% in the no TOT group (difference, -2.9%; 95% confidence interval, -10.7 to 4.9). CONCLUSIONS: The advantage of concomitant TOT for SUI after SCP that was seen at 2 years remained at 5 years. Long-term POP failure rates after SCP are low and not affected by concomitant TOT.


Assuntos
Prolapso de Órgão Pélvico , Slings Suburetrais , Incontinência Urinária por Estresse , Feminino , Humanos , Estudos Prospectivos , Resultado do Tratamento
13.
J Asthma ; 57(10): 1071-1082, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31274042

RESUMO

Objective: Asthma self-management depends partly on access to inhalers; for children, this includes independent inhaler carry and use at school ("self-carry"). Although laws and policies support self-carry, little is known about practices within schools. This study aimed to identify factors associated with inhaler self-carry among children and examine barriers and facilitators to self-carry.Methods: This mixed-methods observational study included child-parent dyads and nurses from four Chicago schools. Children and parents answered questions about asthma care and morbidity, confidence in self-carry skills, and facilitators and barriers to self-carry. Nurses reported asthma documentation on file and their confidence in children's self-carry skills. Analysis utilized logistic regression. Thematic analysis was performed for open-ended questions.Results: Of 65 children enrolled (mean = 10.66 years), 45 (69.2%) reported having quick-relief medication at school, primarily inhalers, and 35 (53.8%) reported self-carry. Inhaler self-carry was associated with controller medication use and parent confidence in child's self-carry skills. Children and parents identified several facilitators to self-carry: child's asthma knowledge, inhaler characteristics, and need for easy inhaler access. Barriers included child's limited understanding of asthma and inhalers, perception that inhaler is not needed, and limited inhaler access. Children also emphasized social relationships as facilitators and barriers, while parents described children's responsibility as a facilitator and inconsistent policy implementation as a barrier.Conclusions: Efforts to improve inhaler self-carry at school should focus on educating children about asthma and inhaler use, creating supportive environments for self-carry among peers and teachers, and fostering consistent implementation and communication about asthma policy among schools and families.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Nebulizadores e Vaporizadores , Serviços de Saúde Escolar/normas , Administração por Inalação , Adolescente , Negro ou Afro-Americano , Antiasmáticos/administração & dosagem , Chicago , Criança , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Modelos Logísticos , Masculino , Pais/psicologia , Pobreza , Serviços de Enfermagem Escolar/normas , Autoimagem
14.
BMC Nephrol ; 21(1): 301, 2020 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-32711448

RESUMO

BACKGROUND: For chronic kidney disease (CKD) patients, management of nutritional status is critical for delaying progression to end-stage renal disease. The purpose of this study is to provide the basis for personalized nutritional intervention in pre-dialysis patients by comparing the foods contributing to nutrients intake, nutritional status and potential dietary inflammation of CKD patients according to the diabetes mellitus (DM) comorbidity and CKD stage. METHODS: Two hundred fifty-six outpatients referred to the Department of Nephrology at SNUH from Feb 2016 to Jan 2017 were included. Subjects on dialysis and those who had undergone kidney transplantation were excluded. Bioelectrical impedance analysis (BIA), subjective global assessment (SGA), dietary intake, and biochemical parameters were collected. Subjects were classified into 4 groups according to DM comorbidity (DM or Non-DM) and CKD stage (Early or Late) by kidney function. Two-way analysis of variance and multinomial logistic regression analysis were performed for statistical analysis. RESULTS: Total number of malnourished patients was 31 (12.1%), and all of them were moderately malnourished according to SGA. The body mass index (BMI) of the DM-CKD group was significantly higher than the Non-DM-CKD group. The contribution of whole grains and legumes to protein intake in the DM-CKD group was greater than that in the Non-DM-CKD group. The DM- Early-CKD group consumed more whole grains and legumes compared with the Non-DM-Early-CKD group. The subjects in the lowest tertile for protein intake had lower phase angle, SGA score and serum albumin levels than those in the highest tertile. The potential for diet-induced inflammation did not differ among the groups. CONCLUSIONS: Significant differences in intakes of whole grains and legumes between CKD patients with or without DM were observed. Since contribution of whole grains and legumes to phosphorus and potassium intake were significant, advice regarding whole grains and legumes may be needed in DM-CKD patients if phosphorus and potassium intake levels should be controlled. The nutritional status determined by BIA, SGA and serum albumin was found to be different depending on the protein intake. Understanding the characteristics of food sources can provide a basis for individualized nutritional intervention for CKD patients depending on the presence of diabetes.


Assuntos
Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/metabolismo , Dieta , Inflamação/metabolismo , Estado Nutricional , Insuficiência Renal Crônica/metabolismo , Idoso , Composição Corporal , Estudos Transversais , Progressão da Doença , Impedância Elétrica , Fabaceae , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fósforo na Dieta , Potássio na Dieta , Índice de Gravidade de Doença , Grãos Integrais
15.
Proc Natl Acad Sci U S A ; 114(39): 10479-10484, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28894008

RESUMO

Genome-wide association studies have implicated the ANK3 locus in bipolar disorder, a major human psychotic illness. ANK3 encodes ankyrin-G, which organizes the neuronal axon initial segment (AIS). We generated a mouse model with conditional disruption of ANK3 in pyramidal neurons of the adult forebrain (Ank-G cKO). This resulted in the expected loss of pyramidal neuron AIS voltage-gated sodium and potassium channels. There was also dramatic loss of markers of afferent GABAergic cartridge synapses, resembling the cortical microcircuitry changes in brains from psychotic patients, and suggesting disinhibition. Expression of c-fos was increased in cortical pyramidal neurons, consistent with increased neuronal activity due to disinhibition. The mice showed robust behavioral phenotypes reminiscent of aspects of human mania, ameliorated by antimania drugs lithium and valproate. Repeated social defeat stress resulted in repeated episodes of dramatic behavioral changes from hyperactivity to "depression-like" behavior, suggestive of some aspects of human bipolar disorder. Overall, we suggest that this Ank-G cKO mouse model recapitulates some of the core features of human bipolar disorder and indicates that cortical microcircuitry alterations during adulthood may be involved in pathogenesis. The model may be useful for studying disease pathophysiology and for developing experimental therapeutics.


Assuntos
Anquirinas/genética , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/genética , Prosencéfalo/fisiopatologia , Sinapses/patologia , Animais , Transtorno Bipolar/fisiopatologia , Modelos Animais de Doenças , Neurônios GABAérgicos/patologia , Lítio/farmacologia , Metilfenidato/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Proteínas Proto-Oncogênicas c-fyn/biossíntese , Ácido Valproico/farmacologia , Canais de Sódio Disparados por Voltagem/genética
16.
J Korean Med Sci ; 35(23): e181, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32537952

RESUMO

BACKGROUND: Dietary intervention at the early stage of chronic kidney disease (CKD) is important for preventing progression to the end-stage renal disease (ESRD). However, few studies have investigated dietary intake of CKD patients in non-dialysis stage. Therefore, we investigated the dietary intake of Korean non-dialysis CKD patients and aimed to establish baseline data for the development of dietary education and intervention strategies for CKD patients. METHODS: Three hundred fifty CKD patients who visited Seoul National University Hospital outpatient clinic from February 2016 to January 2017 were recruited for this cross-sectional study. Subjects on dialysis and those who had undergone kidney transplantation were excluded. Dietary intake, demographic information, and biochemical characteristics of 256 subjects who completed three-day dietary records were analyzed. Subjects were divided into four groups based on diabetes mellitus (DM) (DM-CKD and Non-DM-CKD groups) and kidney function (Early-CKD and Late-CKD groups). RESULTS: Total energy intake was lower in the Late-CKD group compared with the Early-CKD group. In men, carbohydrate intake was higher and protein and fat intakes tended to be lower in the Late-CKD group compared with the Early-CKD group. In women, carbohydrate intake tended to be lower in the DM-CKD group than the Non-DM-CKD group. Protein intake tended to be higher in the DM-CKD groups. Phosphorus and sodium intakes were higher in the DM-CKD groups compared with the Non-DM-CKD groups in women, and tended to be higher in the DM-CKD groups in men. CONCLUSION: DM and kidney function affected energy and nutrient intakes. Subjects in the Late-CKD group consumed less energy than those in the Early-CKD group. Non-DM subjects seemed to restrict protein intake starting from the Early-CKD stage than subjects with DM. Subjects in this study had low energy and high sodium intakes compared with recommended levels. Protein intake was lower in advanced CKD patients, but their intake level was still higher than the recommendation. Dietary intervention strategies for non-dialysis CKD patients need to be customized depending on the presence of DM and kidney function.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Avaliação Nutricional , Insuficiência Renal Crônica/diagnóstico , Idoso , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Ingestão de Energia , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Insuficiência Renal Crônica/complicações , República da Coreia
17.
Phys Rev Lett ; 123(21): 217601, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31809179

RESUMO

Epitaxial oxide ferroelectric films exhibit emerging phenomena arising from complex domain configurations even at pseudoequilibrium, including the creation of domain states unfavored in nature and abrupt piezoelectric coefficients around morphotropic phase boundaries. The nanometer-sized domain configurations and their domain switching dynamics under external stimuli are directly linked to the ultrafast manipulation of ferroelectric thin films; however, complex domain switching dynamics under homogeneous electric fields has not been fully explored, especially at the nanosecond timescale. This Letter reports the nanosecond dynamics of ferroelastic-domain switching from the 90° to 180° direction using time-resolved x-ray microdiffraction under homogeneous electric fields onto an epitaxial Pb(Zr_{0.35},Ti_{0.65})O_{3} film capacitor. It is found that the application of electric fields induces spatially heterogeneous domain switching processes via intermediate domain structures with rotated polarization vectors. In addition, the domain switching time is shown to be inversely proportional to the magnitude of the applied electric field, and electric fields higher than 480 kV/cm are found to complete the ferroelastic switching within nanoseconds.

18.
BMC Nephrol ; 21(1): 2, 2019 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-31892319

RESUMO

BACKGROUND: Online haemodiafiltration (OL-HDF) may improve middle molecular clearance in contrast to conventional haemodialysis (HD). However, OL-HDF requires higher convective flows and cannot sufficiently remove large middle molecules. This study evaluated the efficacy of a medium cut-off (MCO) dialyser in removing large middle molecular uraemic toxins and compared it with that of conventional high-flux (HF) dialysers in HD and predilution OL-HDF. METHODS: Six clinically stable HD patients without residual renal function were investigated. Dialyser and treatment efficacies were examined during a single midweek treatment in three consecutive periods: 1) conventional HD using an HF dialyser, 2) OL-HDF using the same HF dialyser, and 3) conventional HD using an MCO dialyser. Treatment efficacy was assessed by calculating the reduction ratio (RR) for ß2-microglobulin (ß2M), myoglobin, κ and λ free light chains (FLCs), and fibroblast growth factor (FGF)-23 and measuring clearance for FLCs. RESULTS: All three treatments showed comparable RRs for urea, phosphate, creatinine, and uric acid. MCO HD showed greater RRs for myoglobin and λFLC than did HF HD and predilution OL-HDF (myoglobin: 63.1 ± 5.3% vs. 43.5 ± 8.9% and 49.8 ± 7.3%; λFLC: 43.2 ± 5.6% vs. 26.8 ± 4.4% and 33.0 ± 9.2%, respectively; P <  0.001). Conversely, predilution OL-HDF showed the greatest RR for ß2M, whereas MCO HD and HF HD showed comparable RRs for ß2M (predilution OL-HDF vs. MCO HD: 80.1 ± 4.9% vs. 72.6 ± 3.8%, P = 0.01). There was no significant difference among MCO HD, HF HD, and predilution OL-HDF in the RRs for κFLC (63.2 ± 6.0%, 53.6 ± 15.5%, and 61.5 ± 7.0%, respectively; P = 0.37), and FGF-23 (55.5 ± 20.3%, 34.6 ± 13.1%, and 35.8 ± 23.2%, respectively; P = 0.13). Notably, MCO HD showed improved clearances for FLCs when compared to HF HD or OL-HDF. CONCLUSIONS: MCO HD showed significantly greater RR of large middle molecules and achieved improved clearance for FLCs than conventional HD and OL-HDF, without the need for large convection volumes or high blood flow rates. This would pose as an advantage for elderly HD patients with poor vascular access and HD patients without access to OL-HDF. TRIAL REGISTRATION: Clinical Research Information Service (CRIS): KCT 0003009. The trial was prospectively registered on the 21 Jul 2018.


Assuntos
Hemodiafiltração , Membranas Artificiais , Diálise Renal/métodos , Idoso , Fator de Crescimento de Fibroblastos 23 , Hemodiafiltração/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Diálise Renal/instrumentação , Urina/química
19.
Phys Chem Chem Phys ; 20(23): 16176-16183, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29862403

RESUMO

In ferroelectric (FE) polymer-semiconducting polymer blend based organic resistive random access memory devices (ReRAM), the carriers are injected into the semiconductor region of the blend because of the polarization originated internal electric field in the FE polymer. A higher concentration of semiconducting polymer in the FE polymer-semiconducting polymer blends usually generate a high leakage current and degrades the FE characteristics of the FE polymer resulting in a high OFF current and consequently a low ON/OFF ratio. In order to achieve a high ON/OFF ratio in the FE polymer/semiconducting polymer blends, the FE properties of the FE polymer should be preserved. In this study, organic ReRAMs based on ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) and ZnO nanoparticle (NPs) blends exhibiting bipolar resistive switching and a high ON/OFF ratio were realized using a low-cost solution process. Unlike conventional ferroelectric polymer-semiconducting polymer blend systems where FE characteristics are suppressed in ReRAMs, our Au/P(VDF-TrFE)_ZnO NPs/n++Si devices retain the FE characteristics of the P(VDF-TrFE) polymers. Our devices switch between bi-stable resistance states via the ferroelectric-assisted filamentary conduction mechanism. Based on ex situ transmission electron microscopy and elemental mapping analyses, we found that the resistive switching occurs through the formation of conduction paths consisting of Zn-rich/F-deficient regions. The device fabricated at a blend ratio of 20 wt% ZnO NPs in P(VDF-TrFE) matrix exhibited optimal stable resistive switching behavior with an ON/OFF ratio of up to 2 × 107 and a retention time of 104 s.

20.
Molecules ; 23(11)2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30400632

RESUMO

Necroptosis, or caspase-independent programmed cell death, is known to be involved in various pathological conditions, such as ischemia/reperfusion injury, myocardial infarction, atherosclerosis, and inflammatory bowel diseases. Although several inhibitors of necroptosis have been identified, none of them are currently in clinical use. In the present study, we identified a new compound, 4-({[5-(4-aminophenyl)-4-ethyl-4H-1,2,4-triazol-3-yl]sulfanyl}methyl)-N-(1,3-thiazol-2-yl) benzamide (NTB451), with significant inhibitory activity on the necroptosis induced by various triggers, such as tumor necrosis factor-α (TNF-α) and toll-like receptor (TLR) agonists. Mechanistic studies revealed that NTB451 inhibited phosphorylation and oligomerization of mixed lineage kinase domain like (MLKL), and this activity was linked to its inhibitory effect on the formation of the receptor interacting serine/threonine-protein kinase 1 (RIPK1)-RIPK3 complex. Small interfering RNA (siRNA)-mediated RIPK1 knockdown, drug affinity responsive target stability assay, and molecular dynamics (MD) simulation study illustrated that RIPK1 is a specific target of NTB451. Moreover, MD simulation showed a direct interaction of NTB451 and RIPK1. Further experiments to ensure that the inhibitory effect of NTB451 was restricted to necroptosis and NTB451 had no effect on nuclear factor-κB (NF-κB) activation or apoptotic cell death upon triggering with TNF-α were also performed. Considering the data obtained, our study confirmed the potential of NTB451 as a new necroptosis inhibitor, suggesting its therapeutic implications for pathological conditions induced by necroptotic cell death.


Assuntos
Apoptose/efeitos dos fármacos , Imidazóis/farmacologia , Necrose/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imidazóis/química , Modelos Moleculares , Estrutura Molecular , NF-kappa B/metabolismo , Necrose/tratamento farmacológico , Fosforilação/efeitos dos fármacos , Conformação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Receptor 3 Toll-Like/química , Receptor 3 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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