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1.
J Pharmacol Sci ; 148(4): 377-386, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35300813

RESUMO

Metabolic syndrome is increasingly common, and closely related with overweight or obesity. In the obese state, macrophages infiltrate to the adipose tissue (AT), resulting in chronic inflammation and insulin resistance in the AT cells. Recently, attention has been paid to the role of AT macrophages in metabolic disorders should be applied to the initial drug screening step, but it was difficult to mimic the inflammatory adipocytes using the traditional 2-dimensional (2D) culture. In this study, we developed the 3-dimensional (3D) culture system to overcome this limitation. After adipogenic differentiation, lipid droplets were highly accumulated in cells, and differentiation of preadipocytes was not declined by macrophage co-culture. However, only co-cultured cells expressed the insulin resistance features. Compare to mono-cultured adipocytes, co-cultured adipocytes showed reduced glucose uptake and GLUT4 did not translocated to cell membrane even though treatment of high concentration of insulin. Using 3D co-culture model, we develop a microwell-scale drug screening protocol to test anti-obesity effect. 3D cultured cells reacted more sensitive to drugs, and PPARγ antagonist GW9662 (10, 20 µM) repressed adipogenic differentiation in a concentration-dependent manner in 3D co-cultured cells.


Assuntos
Síndrome Metabólica , Adipócitos , Adipogenia , Avaliação Pré-Clínica de Medicamentos , Humanos , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Obesidade/tratamento farmacológico
2.
Diabetes Obes Metab ; 22(8): 1302-1315, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32173999

RESUMO

AIM: Insulin resistance is a metabolic state where insulin sensitivity is lower than normal condition and strongly related to type 2 diabetes. However, an in vitro model mimicking insulin resistance is rare and thus screening drugs for insulin resistance severely depends on an in vivo model. Here, to increase anti-diabetic drug selectivity for humans, 3D ADMSCs and macrophages were co-cultured with in-house fabricated co-culture plates. MATERIAL AND METHODS: 3D co-culture plates were designed to load ADMSCs and RAW264.7 cells containing hydrogels in separate wells while allowing cell-cell interaction with co-culturing media. Hydrogels were constructed using a 3D cell-printing system containing 20 mg/ml alginate, 0.5 mg/ml gelatin and 0.5 mg/ml type I collagen. Cells containing hydrogels in 3D co-culture plates were incubated for 10 min to allow stabilization before the experiment. 3D co-culture plates were incubated with the CaCl2 solution for 5 min to complete the cross linking of alginate hydrogel. Cells in 3D co-culture plates were cultured for up to 12 days depending on the experiment and wells containing adipocytes and macrophages were separated and used for assays. RESULTS: KR-1, KR-2 and KR-3 compounds were applied during differentiation (12 days) in 3D co-cultured mouse 3T3-L1 adipocytes and 3D co-cultured human ADMSCs. Glucose uptake assay using 2-DG6P and 2-NBDG and western blot analysis were performed to investigate changes of insulin resistance in the 3D co-cultured model for interspecies selectivity of drug screening. KR-1 (mouse potent enantiomer) and KR-3 (racemic mixture) showed improvement of 2-DG and 2-NBDG uptake compared with KR-2 (human potent enantiomer) in 3D co-cultured 3T3-L1 adipocytes. In connection with insulin resistance in a 3D 3T3-L1 co-cultured model, KR-1 and KR-3 showed improvement of insulin sensitivity compared to KR-2 by markedly increasing GLUT4 expression. In contrast to the result of 3D co-cultured 3T3-L1 adipocytes, KR-1 failed to significantly improve 2-DG and 2-NBDG uptake in 3D co-cultured ADMSC adipocytes. Results of 2-NBDG accumulation and western blot analysis also showed that KR-2 and KR-3 improved insulin sensitivity relatively better than KR-1. CONCLUSIONS: Our 3D co-culture model with/without 3D co-culture plates can successfully mimic insulin resistance while allowing investigation of the effects of anti-obesity or anti-diabetic drugs on human or mouse co-culturing cell type. This 3D co-culture system may accelerate screening of drugs for insulin resistance depending on species.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Preparações Farmacêuticas , Células 3T3-L1 , Adipócitos , Animais , Técnicas de Cocultura , Glucose , Humanos , Insulina , Camundongos
3.
Transfus Apher Sci ; 59(1): 102631, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31585831

RESUMO

BACKGROUND: Massive transfusion protocol (MTP) has been used to provide plasma and packed red blood cells (pRBCs) rapidly. MTP also has been adapted for non-traumatic patients. The effects of hospital-wide MTP implementation on clinical outcomes were reviewed. METHODS: This was a retrospective study of patients who received massive transfusion before and after MTP implementation, between August 2010 and May 2018. Massive transfusion was defined as 10 or more units of pRBCs within 24 h. Recipients of massive transfusion were divided into periods before and after MTP implementation. The 24 -h death rate, thirty-day death rate and several laboratory findings were investigated. RESULTS: Eighty patients whose massive transfusion occurred before MTP implementation and 63 patients whose massive transfusion occurred after MTP implementation were compared. No statistically significant difference was found in 24 -h death rate (15.0% vs. 23.8%, p = 0.181), or 30-day death rate (43.8% vs. 36.5%, p = 0.381). Use of an anti-fibrinolytic agent was more frequent in patients after the MTP implementation (31.3% vs. 55.6%, p = 0.003). A statistically significant difference was found in the lowest body temperature of the two groups during the 24 -h period (34.7 °C vs. 35.6 °C, p < 0.001). Transfusion ratio of plasma to pRBC was numerically improved after the MTP implementation (1:1.91 vs. 1:1.58, p = 0.173). Earlier initiation of pRBC transfusion was achieved after implementation (51 min vs. 40 min, p = 0.042). CONCLUSIONS: MTP implementation showed improved coagulation profiles, but did not show a statistically significant death-rate reduction in non-traumatic patients.


Assuntos
Transfusão de Sangue/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
J Korean Med Sci ; 35(23): e168, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32537949

RESUMO

Philadelphia-negative (Ph-) classical myeloproliferative neoplasms (MPNs) include polycythemia vera, essential thrombocythemia (ET), and primary myelofibrosis. Somatic driver mutations in the JAK2, CALR, and MPL genes serve as major diagnostic criteria of the Ph- MPNs and these mutations occur in a mutually exclusive manner. In this report, we describe the first case of ET harboring double mutations in JAK2 V617F and MPL. For MPL, the patient had multiple clones of MPL mutations: c.1543_1546delinsAGGG (p.Trp515_Gln516delinsArgGlu) and c.1546C>G (p.Gln516Glu). The JAK2 V617F allele burden in our patient is very low (4%) compared to the relatively high (17%-78%) allele frequency of MPL mutations. The low JAK2 mutant burden might be explained by preexisting clonal hematopoiesis before overt signs of MPNs, followed by the acquisition of a second oncogenic mutation of CALR or MPL leading to the MPN phenotype. This highlights that screening for a second driver mutation should be considered in patients with a low JAK2 mutant burden by reporting a 57-year-old Korean man with ET.


Assuntos
Janus Quinase 2/genética , Receptores de Trombopoetina/genética , Trombocitemia Essencial/diagnóstico , Sequência de Bases , Medula Óssea/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Trombocitemia Essencial/genética
5.
Nano Lett ; 19(2): 971-976, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30608699

RESUMO

Organic-inorganic hybrid perovskites have been investigated extensively for use in perovskite-based solar cells and light-emitting diodes (LEDs) because of their excellent electrical and optical properties. Although the flexibility of perovskite LEDs has been studied through empirical methods such as cyclic bending tests, the flexibility of the perovskite layer has not been investigated systemically. Here, flexible and semitransparent perovskite LEDs are fabricated: a PEDOT:PSS anode and Ag nanowire cathode allow for flexible and semitransparent devices, while the use of a conjugated polyelectrolyte as an interfacial layer reduces the electron injection barrier between the cathode and the electron transport layer (SPW-111), resulting in enhanced device efficiency. Cyclic bending tests performed on the electrodes and in situ hole-nanoindentation tests performed on the constituent materials suggest that mechanical failure occurs in the perovskite MAPbBr3 layer during cyclic bending, leading to a decrease in the luminance. Tensile properties of the MAPbBr3 layer explain the critical bending radius ( rb) of the perovskite LEDs on the order of 1 mm.

6.
Int J Mol Sci ; 21(10)2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32466320

RESUMO

Dry eye syndrome is the most common eye disease and it is caused by various reasons. As the balance of the tear film that protects the eyes is broken due to various causes, it becomes impossible to properly protect the eyes. In this study, the protective effects and underlying mechanisms of topical (E)-4-(2-(6-(2,6-dichloro-4-(trifluoromethyl)phenyl)-4-methyl-1,1-dioxido-1,2,6-thiadiazinan-2-yl)acetamido)adamantan-1-carboxamide (KR-67607), a novel selective 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) inhibitor, were investigated in benzalkonium chloride (BAC)-induced dry eye syndrome. BAC-treated rat eyes induced significant increases in ocular surface damage, decreased corneal thickness, corneal basement membrane destruction in the conjunctival epithelium, and expression of pro-inflammatory cytokines tumor necrosis factor-α and 11ß-HSD1. These effects of BAC were reversed by topical KR-67607 treatment. Furthermore, KR-67607 decreased 4-hydroxynonenal expression and increased antioxidant and mucus secretion in BAC-treated rat eyes. Taken together, a novel selective 11ß-HSD1 inhibitor can prevent BAC-induced dry eye syndrome by inhibiting pro-inflammatory cytokine and reactive oxygen species expression via the inhibition of both 11ß-HSD1 activity and expression.


Assuntos
Adamantano/análogos & derivados , Antioxidantes/uso terapêutico , Síndromes do Olho Seco/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Tiadiazinas/uso terapêutico , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adamantano/farmacologia , Adamantano/uso terapêutico , Animais , Antioxidantes/farmacologia , Compostos de Benzalcônio/toxicidade , Túnica Conjuntiva/efeitos dos fármacos , Túnica Conjuntiva/metabolismo , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/prevenção & controle , Inibidores Enzimáticos/farmacologia , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Tiadiazinas/farmacologia
7.
Apoptosis ; 22(11): 1441-1453, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28887719

RESUMO

Dry eye syndrome (DES) is a disorder of the eye due to tear deficiency or excessive evaporation that causes damage to the eye and is associated with discomfort and dryness. 11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) is an enzyme that converts inactive cortisone to active cortisol. Recently, 11ß-HSD1 has been expressed in human and rodent eyes and has been recognized as a target of glaucoma. In this study, the therapeutic effects and underlying mechanisms of topical carbenoxolone, an 11ß-HSD1 inhibitor, were investigated in benzalkonium chloride (BAC)-treated human conjunctival epithelial cells and a rat DES model. In the in vitro study, carbenoxolone dose-dependently inhibited cell death and 11ß-HSD1 activity in BAC-treated human conjunctival epithelial cells. For the in vivo study, carbenoxolone or a solvent was administered to the BAC-induced DES model twice daily. BAC-treated rat eyes showed significant increases in ocular surface damage, a reduction of tears, decrease corneal thickness, corneal basement membrane destruction, apoptosis in the conjunctival epithelium, and expression of pro-inflammatory cytokines (TNF-α and IL-6) and 11ß-HSD1. These effects of BAC were reversed by topical carbenoxolone treatment. These results demonstrate that carbenoxolone can prevent DES by inhibiting pro-inflammatory cytokine expression and cell death of the corneal and conjunctival epithelium via inhibition of both 11ß-HSD1 activity and expression in the eyes of BAC-treated rats. It is suggested that topical 11ß-HSD1 inhibitors may provide a new therapeutic window in the prevention and/or treatment of DES.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Carbenoxolona/farmacologia , Túnica Conjuntiva/efeitos dos fármacos , Síndromes do Olho Seco/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Soluções Oftálmicas/farmacologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Compostos de Benzalcônio/administração & dosagem , Linhagem Celular , Túnica Conjuntiva/citologia , Túnica Conjuntiva/metabolismo , Relação Dose-Resposta a Droga , Síndromes do Olho Seco/induzido quimicamente , Síndromes do Olho Seco/genética , Síndromes do Olho Seco/patologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Small ; 13(37)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28834195

RESUMO

The performance of plasmonic Au nanostructure/metal oxide heterointerface shows great promise in enhancing photoactivity, due to its ability to confine light to the small volume inside the semiconductor and modify the interfacial electronic band structure. While the shape control of Au nanoparticles (NPs) is crucial for moderate bandgap semiconductors, because plasmonic resonance by interband excitations overlaps above the absorption edge of semiconductors, its critical role in water splitting is still not fully understood. Here, first, the plasmonic effects of shape-controlled Au NPs on bismuth vanadate (BiVO4 ) are studied, and a largely enhanced photoactivity of BiVO4 is reported by introducing the octahedral Au NPs. The octahedral Au NP/BiVO4 achieves 2.4 mA cm-2 at the 1.23 V versus reversible hydrogen electrode, which is the threefold enhancement compared to BiVO4 . It is the highest value among the previously reported plasmonic Au NPs/BiVO4 . Improved photoactivity is attributed to the localized surface plasmon resonance; direct electron transfer (DET), plasmonic resonant energy transfer (PRET). The PRET can be stressed over DET when considering the moderate bandgap semiconductor. Enhanced water oxidation induced by the shape-controlled Au NPs is applicable to moderate semiconductors, and shows a systematic study to explore new efficient plasmonic solar water splitting cells.

9.
Pharmacol Res ; 123: 62-72, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28687341

RESUMO

Glaucoma is one of the leading causes of preventable blindness diseases, affecting more than 2 million people in the United States. Recently, 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) inhibitors were found to exert preventive effects against glaucoma. Therefore, we investigated whether carbenoxolone (CBX), an 11ß-HSD1 inhibitor, prevents chemical ischemia-reperfusion-induced cell death in human trabecular meshwork (HTM) cells. The present study demonstrated that CBX inhibited cell death caused by iodoacetic acid (IAA)-induced ischemia-reperfusion, and its effect was associated with the inhibition of 11ß-HSD1 expression and activity. Furthermore, CBX reversed the IAA-induced structural damage on filamentous actin in HTM cells. In IAA-treated cells, the levels of 11ß-HSD1 and the apoptosis-related factors Bax and FASL were increased throughout the reperfusion period, and CBX was able to attenuate the expression of 11ß-HSD1 and the apoptosis-related factors. CBX also effectively suppressed IAA-induced intracellular ROS formation and cytochrome c release, which are involved in the mitochondrial apoptosis pathway. In addition, IAA-induced chemical ischemia-reperfusion stimulated TNF-α expression and NF-κB p65 phosphorylation, and these effects were attenuated by CBX. 11ß-HSD1 RNAi also suppressed IAA-induced cell apoptosis via reduction of oxidative stress and inhibition of the pro-inflammatory pathway. Taken together, the present study demonstrated that the inhibition of 11ß-HSD1 protected the TM against chemical ischemia-reperfusion injury, suggesting that the use of 11ß-HSD1 inhibitors could be a useful strategy for glaucoma therapy.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Carbenoxolona/farmacologia , Traumatismos Oculares/prevenção & controle , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/prevenção & controle , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocromos c/metabolismo , Traumatismos Oculares/induzido quimicamente , Traumatismos Oculares/metabolismo , Humanos , Ácido Iodoacético , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/induzido quimicamente , Traumatismo por Reperfusão/metabolismo , Malha Trabecular/citologia , Fator de Necrose Tumoral alfa/metabolismo
10.
Nanotechnology ; 28(39): 395402, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28699921

RESUMO

Well-ordered nanostructure arrays with controlled densities can potentially improve material properties; however, their fabrication typically involves the use of complicated processing techniques. In this work, we demonstrate a uniaxial alignment procedure for fabricating poly(vinylidene fluoride) (PVDF) electrospun nanofibers (NFs) by introducing collectors with additional steps. The mechanism of the observed NF alignment, which occurs due to the concentration of lateral electric field lines around collector steps, has been elucidated via finite-difference time-domain simulations. The membranes composed of well-aligned PVDF NFs are characterized by a higher content of the PVDF ß-phase, as compared to those manufactured from randomly orientated fibers. The piezoelectric energy harvester, which was fabricated by transferring well-aligned PVDF NFs onto flexible substrates with Ag electrodes attached to both sides, exhibited a 2-fold increase in the output voltage and a 3-fold increase in the output current as compared to the corresponding values obtained for the device manufactured from randomly oriented NFs. The enhanced piezoresponse observed for the aligned PVDF NFs is due to their higher ß-phase content, denser structure, smaller effective radius of curvature during bending, greater applied strain, and higher fraction of contributing NFs.

11.
J Pharmacol Sci ; 131(4): 241-50, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27523796

RESUMO

11ß-Hydroxysteroid dehydrogenase type 1 (11ß-HSD1) converts inactive cortisone to the active cortisol. 11ß-HSD1 may be involved in the resolution of inflammation. In the present study, we investigate the anti-inflammatory effects of 2-(3-benzoyl)-4-hydroxy-1,1-dioxo-2H-1,2-benzothiazine-2-yl-1-phenylethanone (KR-66344), a selective 11ß-HSD1 inhibitor, in lipopolysaccharide (LPS)-activated C57BL/6J mice and macrophages. LPS increased 11ß-HSD1 activity and expression in macrophages, which was inhibited by KR-66344. In addition, KR-66344 increased survival rate in LPS treated C57BL/6J mice. HO-1 mRNA expression level was increased by KR-66344, and this effect was reversed by the HO competitive inhibitor, ZnPP, in macrophages. Moreover, ZnPP reversed the suppression of ROS formation and cell death induced by KR-66344. ZnPP also suppressed animal survival rate in LPS plus KR-66344 treated C57BL/6J mice. In the spleen of LPS-treated mice, KR-66344 prevented cell death via suppression of inflammation, followed by inhibition of ROS, iNOS and COX-2 expression. Furthermore, LPS increased NFκB-p65 and MAPK phosphorylation, and these effects were abolished by pretreatment with KR-66344. Taken together, KR-66344 protects against LPS-induced animal death and spleen injury by inhibition of inflammation via induction of HO-1 and inhibition of 11ß-HSD1 activity. Thus, we concluded that the selective 11ß-HSD1 inhibitor may provide a novel strategy in the prevention/treatment of inflammatory disorders in patients.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Anti-Inflamatórios/farmacologia , Óxidos S-Cíclicos/farmacologia , Heme Oxigenase-1/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Tiazinas/farmacologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Óxidos S-Cíclicos/antagonistas & inibidores , Ciclo-Oxigenase 2/biossíntese , Interações Medicamentosas , Heme Oxigenase-1/biossíntese , Inflamação/induzido quimicamente , Camundongos , Óxido Nítrico Sintase Tipo II/biossíntese , Fosforilação/efeitos dos fármacos , Protoporfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Taxa de Sobrevida , Tiazinas/antagonistas & inibidores
12.
Nano Lett ; 15(10): 6658-64, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26359631

RESUMO

Managing interfacial instability is crucial for enhancing cyclability in lithium-ion batteries (LIBs), yet little attention has been devoted to this issue until recently. Here, we introduce graphene as an interfacial layer between the current collector and the anode composed of Si nanowires (SiNWs) to improve the cycling capability of LIBs. The atomically thin graphene lessened the stress accumulated by volumetric mismatch and inhibited interfacial reactions that would accelerate the fatigue of Si anodes. By simply incorporating graphene at the interface, we demonstrated significantly enhanced cycling stability for SiNW-based LIB anodes, with retentions of more than 2400 mAh/g specific charge capacity over 200 cycles, 2.7 times that of SiNWs on a bare current collector.

13.
ACS Nano ; 18(27): 17764-17773, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38935840

RESUMO

Vacuum deposition of perovskites is a promising method for scale-up fabrication and uniform film growth. However, improvements in the photovoltaic performance of perovskites are limited by the fabrication of perovskite films, which are not optimized for high device efficiency in the vacuum evaporation process. Herein, we fabricate CsPbI2Br perovskite with high crystallinity and larger grain size by controlling the deposition sequence between PbI2 and CsBr. The nucleation barrier for perovskite formation is significantly lowered by first evaporating CsBr and then PbI2 (CsBr-PbI2), followed by the sequential evaporation of multiple layers. The results show that the reduced Gibbs free energy of CsBr-PbI2, compared with that of PbI2-CsBr, accelerates perovskite formation, resulting in larger grain size and reduced defect density. Furthermore, surface-modified homojunction perovskites are fabricated to efficiently extract charge carriers and enhance the efficiency of perovskite solar cells (PeSCs) by modulating the final PbI2 thickness before thermal annealing. Using these strategies, the best PeSC exhibits a power conversion efficiency of 13.41% for a small area (0.135 cm2), the highest value among sequential thermal deposition inorganic PeSCs, and 11.10% for a large area PeSC (1 cm2). This study presents an effective way to understand the crystal growth of thermally deposited perovskites and improve their performance in optoelectronic devices.

14.
ACS Nano ; 18(10): 7558-7569, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38420914

RESUMO

Water electrolysis is emerging as a promising renewable-energy technology for the green production of hydrogen, which is a representative and reliable clean energy source. From economical and industrial perspectives, the development of earth-abundant non-noble metal-based and bifunctional catalysts, which can simultaneously exhibit high catalytic activities and stabilities for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), is critical; however, to date, these types of catalysts have not been constructed, particularly, for high-current-density water electrolysis at the industrial level. This study developed a heterostructured zero-dimensional (0D)-one-dimensional (1D) PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF)-Ni3S2 as a self-supported catalytic electrode via interface and morphology engineering. This unique heterodimensional nanostructure of the PBSCF-Ni3S2 system demonstrates superaerophobic/superhydrophilic features and maximizes the exposure of the highly active heterointerface, endowing the PBSCF-Ni3S2 electrode with outstanding electrocatalytic performances in both HER and OER and exceptional operational stability during the overall water electrolysis at high current densities (500 h at 500 mA cm-2). This study provides important insights into the development of catalytic electrodes for efficient and stable large-scale hydrogen production systems.

15.
J Nanosci Nanotechnol ; 13(5): 3511-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23858890

RESUMO

We have characterized the structural properties of the ternary In(x)Ga(1-x)As nanowires (NWs) grown on silicon (Si) substrates using metalorganic chemical vapor deposition (MOCVD). Au catalyzed vapor-liquid-solid (VLS) mode was used for the NW growth. The density of the In(x)Ga(1-x)As NW array grown under optimized condition exceeds 1 x 10(8)/cm2. X-ray diffraction (XRD) spectra confirm the In composition (x = 0.9-0.3) of the In(x)Ga(1-x)As nanowires which bandgap energy can cover the entire near-infrared (NIR) range. Massive stacking faults and twin planes were observed but no misfit dislocation was found along the NWs as confirmed by transmission electron microscopy (TEM). The energy-dispersive X-ray spectroscopy (EDS) analysis shows the gradual variation of In composition along the NW.


Assuntos
Cristalização/métodos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Nanotubos/química , Nanotubos/ultraestrutura , Silício/química , Catálise , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
16.
Sci Rep ; 13(1): 14668, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37674003

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as Non-Alcoholic Fatty Liver Disease, is a widespread liver condition characterized by excessive fat buildup in hepatocytes without significant alcohol consumption. Manipulation of the gut microbiome has been considered to prevent and improve the occurrence and progression of MASLD, particularly through the gut-liver axis. This study aimed to investigate the correlation between the gut microbiome and liver function and determine whether the gut microbiome can ameliorate MASLD. We comparatively analyzed the gut microbiome composition between mice fed normal chow and those fed a high-fat diet and observed that the abundance of Kineothrix alysoides decreased in the high-fat group. Further analysis showed that treatment with K. alysoides in the high-fat diet group led to decreased weight loss, and MASLD attenuation. Importantly, K. alysoides treatment attenuated MASLD in mice fed a high-fat, high-fructose diet (HFHF), which can cause advanced liver damage. Furthermore, administration of K. alysoides altered the gut microbial composition in the HFHF diet group and improved MASLD. Overall, these findings demonstrate the potential of K. alysoides in restoring gut health and facilitating lipid metabolism to prevent and treat MASLD.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Metabolismo dos Lipídeos , Clostridiales
17.
Tissue Eng Regen Med ; 20(1): 49-58, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36374371

RESUMO

BACKGROUND: Microplastics (MPs) are small fragments from any type of plastic formed from various sources, including plastic waste and microfibers from clothing. MPs degrades slowly, resulting in a high probability of human inhalation, ingestion and accumulation in bodies and tissues. As its impact on humans is a prolonged event, the evaluation of its toxicity and influence on human health are critical. In particular, MPs can enter the human digestive system through food and beverage consumption, and its effect on the human colon needs to be carefully examined. METHODS: We monitored the influence of small MPs (50 and 100 nm) on human colon cells, human colon organoids and also examined their toxicity and changes in gene expression in vivo in a mouse model. RESULTS: The data suggested that 5 mg/mL concentrations of 50 and 100 nm MPs induced a > 20% decrease in colon organoid viability and an increase in the expression of inflammatory-, apoptosis- and immunity-related genes. In addition, in vivo data suggested that 50 nm MPs accumulate in various mouse organs, including the colon, liver, pancreas and testicles after 7 d of exposure. CONCLUSION: Taken together, our data suggest that smaller MPs can induce more toxic effects in the human colon and that human colon organoids have the potential to be used as a predictive tool for colon toxicity.


Assuntos
Microplásticos , Plásticos , Humanos , Camundongos , Animais , Microplásticos/toxicidade , Plásticos/toxicidade , Colo , Apoptose , Organoides
18.
J Microbiol ; 60(7): 715-726, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35781626

RESUMO

Nitric oxide (NO) is a reactive nitrogen species (RNS) that plays a vital role in regulating inflammatory processes. Under abnormal conditions, excessive NO levels can promote the oxidation of cellular components, which may cause or exacerbate diseases such as hypertension, cardiovascular dysfunction, and inflammatory bowel disease (IBD). Previous studies have shown that reducing NO levels in the lumen can attenuate the clinical symptoms of IBD. Thus, we aimed to identify bacteria that can reduce RNS and that can be used as valuable probiotics. In this study, we isolated bacteria resistant to nitrite stress from human feces and used 16S and whole-genome sequencing to identify them as Lactiplantibacillus plantarum LP7 (LP7). The ability to survive at high nitrite levels and to decrease them was greater in the LP7 strain than in the reference strain L. plantarum ATCC14917 (ATCC14917). To characterize the LP7 genome in more detail, we performed a comparative genome analysis. However, the unique genes that directly confer the ability to withstand nitrite stress were not present in the LP7 genome. Furthermore, we performed transcriptomic analysis of LP7 and ATCC14917 cells treated with nitrite. We found that the expression levels of genes involved in the cell division process were induced in LP7, which showed a more regular rod-shape than ATCC14917. This could explain why LP7 can survive better than ATCC14917 under nitrite stress. Based on its ability to survive better in nitrite stress and decrease nitrite concentration, we suggest that LP7 could be a valuable probiotic strain.


Assuntos
Doenças Inflamatórias Intestinais , Lactobacillus plantarum , Probióticos , Perfilação da Expressão Gênica , Humanos , Lactobacillus plantarum/metabolismo , Nitritos
19.
Adv Sci (Weinh) ; 9(12): e2104915, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35199951

RESUMO

A wearable thermoelectric generator (WTEG) that utilizes human body heat can be a promising candidate for the wearable power generators. The temperature difference (ΔT) between the body and the environment is a stable source driving the WTEG, but this driving force is limited by the ambient temperature itself at the same time. Here, a novel WTEG that can be operated using the dual source of body heat and light with exceptionally high driving force is fabricated. The printable solar absorbing layer attached to the bottom of the WTEG absorbs ≈95% of the light from ultraviolet to far infrared and converts it into heat. To optimize the power density of WTEGs, the fill factor of the thermoelectric (TE) leg/electrode is considered through finite-difference time-domain (FDTD) simulation. When operated by the dual sources, the WTEG exhibits a power density of 15.33 µW cm-2 , which is the highest under "actual operating conditions" among all kinds of WTEGs. In addition, unlike conventional WTEGs, the WTEG retains 83.1% of its output power at an ambient temperature of 35 °C compared to its output power at room temperature. This study will accelerate the commercialization of WTEGs by introducing a novel method to overcome their limitations.


Assuntos
Temperatura Alta , Dispositivos Eletrônicos Vestíveis , Fontes de Energia Elétrica , Eletrodos , Humanos , Luz Solar
20.
PLoS One ; 17(12): e0279196, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36534676

RESUMO

BACKGROUND: Non-occlusive mesenteric ischemia (NOMI) is a life-threatening acute condition that has an overall in-hospital mortality rate of up to 75%. Critically ill patients are often admitted to intensive care units (ICUs) due to shock, and these patients are frequently at risk of developing NOMI. The objective of this study was to determine the clinical features of critically ill patients with NOMI and evaluate the risk factors for in-hospital mortality among these patients. METHODS: We reviewed the electronic medical records of 7,346 patients who underwent abdominal contrast-enhanced computed tomography during their ICU stay at Samsung Medical Center (Seoul, Korea) between January 1, 2010 and December 31, 2019. After reviewing each patient's computed tomography (CT) scans, 60 patients were diagnosed with NOMI and included in this analysis. The patients were divided into survivor (n = 23) and non-survivor (n = 37) groups according to the in-hospital mortality. RESULTS: The overall sequential organ failure assessment (SOFA) score for the included patients upon admission to the ICU was 8.6 ± 3.1, and medical ICU admissions were most common (66.7%) among the patients. The SOFA score upon admission to the ICU was higher for the non-survivors than for the survivors (9.4 vs. 7.4; p = 0.017). Non-survivors were more often observed in the medical ICU admissions (39.1% vs. 83.8%) than in the surgical ICU admissions (47.8% vs. 10.8%) or the cardiac ICU admissions (13.0% vs. 5.4%). Laboratory test results, abdominal CT findings, and the use of vasopressors and inotropes did not differ between the two groups. In a multivariable analysis, SOFA scores >8 upon admission to the ICU (odds ratio [OR] 4.51; 95% 1.12-18.13; p = 0.034), patients admitted to the ICU with medical problems (OR 7.99; 95% 1.73-36.94; p = 0.008), and abdominal pain (OR 4.26; 95% 1.05-17.35; p = 0.043) were significant prognostic predictors for in-hospital mortality. CONCLUSIONS: The SOFA score >8 upon admission to the ICU, admission to the ICU for medical problems, and abdominal pain at diagnosis are associated with increased mortality among patients with NOMI.


Assuntos
Estado Terminal , Isquemia Mesentérica , Humanos , Mortalidade Hospitalar , Hospitalização , Unidades de Terapia Intensiva , Escores de Disfunção Orgânica , Prognóstico , Estudos Retrospectivos
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