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1.
J Am Chem Soc ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602882

RESUMEN

Hydrogen peroxide (H2O2) holds significance as a vital chemical with the potential to serve as an energy carrier. Compared with the conventional anthraquinone process, photocatalytic H2O2 production has emerged as an appealing alternative because of its energy efficiency and environmental sustainability. However, the existing photocatalysts suffer from low catalytic efficiency, limited tunability of optical properties, and reliance on sacrificial agents due to high energy loss caused by inefficient charge separation. Therefore, developing catalysts with tunable optical properties and efficient charge separation is desirable. In this work, we introduce postsynthetic functionalization into an electrically conductive metal-organic framework, namely, DPT-MOF. Leveraging DPT (3,6-di(4-pyridyl)-1,2,4,5-tetrazine) as a pillar ligand, we exploited click-type chemistry to manipulate band position and charge separation efficiency, allowing for photocatalytic nonsacrificial H2O2 production. Notably, the fluorine-functionalized MOF exhibited the highest H2O2 production rate of 1676 µmol g-1 h-1 under visible light in O2-saturated water among our other samples. This high production rate is attributed to the tuned electronic structure and prolonged charge lifetime facilitated by the fluorine groups. This work highlights the effectiveness of postsynthetic methodology in tuning optical properties, opening a promising avenue for advancing the field of semiconductive MOF-based photocatalysis.

2.
Acc Chem Res ; 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38294773

RESUMEN

ConspectusElectrically conductive metal-organic frameworks (EC-MOFs) have emerged as a compelling class of materials, drawing increasing attention due to their unique properties facilitating charge transport within porous structures. The synergy between electrical conductivity and porosity has opened a wide range of applications, including electrocatalysis, energy storage, chemiresistive sensing, and electronic devices that have been underexplored for their insulating counterparts. Despite these promising prospects, a prevalent challenge arises from the predominant adoption of two-dimensional (2D) structures by most EC-MOFs. These 2D frameworks often show modest surface areas and short interlayer distances, hindering molecular accessibility, which deviates from the inherent characteristics of conventional MOFs. Furthermore, the quest for efficient charge transport imposes design constraints, leading to a restricted selection of functional building blocks. Additionally, there is a lack of established functionalization methods within EC-MOFs, limiting their functional diversity. Thus, these challenges have impeded EC-MOFs from reaching their full potential.In this Account, we summarize and discuss our group's efforts aimed at enhancing molecular accessibility and deploying the functional diversity of EC-MOFs. Our focus on enhancing molecular accessibility involves several strategies. First, we employed macrocyclic ligands with intrinsic pockets as the building blocks for EC-MOFs. The integrated intrinsic pockets in the frameworks supplement surface areas and additional pores to enhance molecular accessibility. The resulting macrocyclic ligand-based EC-MOFs exhibit exceptionally high surface areas and confer advantages in electrochemical performances. Second, our efforts extend to addressing the structural limitations, frequently associated with EC-MOFs' 2D structures. Through the pillar insertion strategy, we transformed a 2D EC-MOF platform into a three-dimensional (3D) structure, thereby achieving higher porosity and enhanced molecular accessibility. In pursuing functional diversity, we have delved into molecular-level tuning of EC-MOF building blocks. We demonstrated that electron-rich alkyne-based pockets in the macrocyclic ligands can host transition metals and alkali ions, enabling ion selectivity and showcasing diverse use of EC-MOFs. We utilized a postsynthetic approach to further functionalize metal nodes on the molecular level within an EC-MOF framework, introducing a proton-conducting pathway while preserving its electrical conductivity.We aspire for this Account to provide practical insights and strategies to surmount structural and functional diversity limitations in the realm of EC-MOFs. By integrating enhanced molecular accessibility and diverse functionality, our endeavor to propel the utility of these materials will inspire further rational development for future EC-MOFs and unlock their full potential.

3.
Fish Shellfish Immunol ; 144: 109277, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38072138

RESUMEN

Along with environmental pollution caused by rapid economic development and industrialization, plastic waste is emerging as a global concern in relation to marine ecosystems and human health. Among the microplastics, fiber-type microfibers (MF) and bisphenol A (BPA), which are widely used as plasticizers, do not decompose well in the ocean, and tend to accumulate in organisms, generating an increased oxidative stress response. This study investigated the abalones' antioxidant and cell death responses following exposure to the environmental pollutants MF and BPA. Levels of malondialdehyde (MDA) and DNA damage increased over time, demonstrating the degree of lipid peroxidation and DNA damage in abalones exposed to individual and combined environmental conditions of MF and BPA. Compared to the single MF and BPA exposure groups, the combined exposure group showed a higher expression of antioxidant enzymes. A similar pattern was seen in the expression of the apoptosis enzyme caspase-3. Both MF and BPA caused oxidative stress and antioxidant enzymes were expressed to alleviate it, but it is believed that cell damage occurred because the stress level exceeded the allowed range.


Asunto(s)
Antioxidantes , Gastrópodos , Humanos , Animales , Antioxidantes/metabolismo , Microplásticos , Plásticos/toxicidad , Bioacumulación , Ecosistema , Estrés Oxidativo , Gastrópodos/genética , Gastrópodos/metabolismo
4.
Medicine (Baltimore) ; 102(47): e36122, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38013289

RESUMEN

BACKGROUND: We compared the efficacy and safety of low-intensity atorvastatin and ezetimibe combination therapy with moderate-intensity atorvastatin monotherapy in patients requiring cholesterol-lowering therapy. METHODS: At 19 centers in Korea, 290 patients were randomized to 4 groups: atorvastatin 5 mg and ezetimibe 10 mg (A5E), ezetimibe 10 mg (E), atorvastatin 5 mg (A5), and atorvastatin 10 mg (A10). Clinical and laboratory examinations were performed at baseline, and at 4-week and 8-week follow-ups. The primary endpoint was percentage change from baseline in low-density lipoprotein (LDL) cholesterol levels at the 8-week follow-up. Secondary endpoints included percentage changes from baseline in additional lipid parameters. RESULTS: Baseline characteristics were similar among the study groups. At the 8-week follow-up, percentage changes in LDL cholesterol levels were significantly greater in the A5E group (49.2%) than in the E (18.7%), A5 (27.9%), and A10 (36.4%) groups. Similar findings were observed regarding the percentage changes in total cholesterol, non-high-density lipoprotein cholesterol, and apolipoprotein B levels. Triglyceride levels were also significantly decreased in the A5E group than in the E group, whereas high-density lipoprotein levels substantially increased in the A5E group than in the E group. In patients with low- and intermediate-cardiovascular risk, 93.3% achieved the target LDL cholesterol levels in the A5E group, 40.0% in the E group, 66.7% in the A5 group, and 92.9% in the A10 group. In addition, 31.4% of patients in the A5E group, 8.1% in E, 9.7% in A5, and 7.3% in the A10 group reached the target levels of both LDL cholesterol < 70 mg/dL and reduction of LDL ≥ 50% from baseline. CONCLUSIONS: The addition of ezetimibe to low-intensity atorvastatin had a greater effect on lowering LDL cholesterol than moderate-intensity atorvastatin alone, offering an effective treatment option for cholesterol management, especially in patients with low and intermediate risks.


Asunto(s)
Anticolesterolemiantes , Azetidinas , Ácidos Heptanoicos , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Hipercolesterolemia , Humanos , Atorvastatina/uso terapéutico , Anticolesterolemiantes/uso terapéutico , LDL-Colesterol , Hipercolesterolemia/tratamiento farmacológico , Azetidinas/uso terapéutico , Ácidos Heptanoicos/efectos adversos , Pirroles/uso terapéutico , Quimioterapia Combinada , Ezetimiba/uso terapéutico , Colesterol , Resultado del Tratamiento , Método Doble Ciego , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico
5.
J Clin Hypertens (Greenwich) ; 25(9): 828-844, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37584254

RESUMEN

The authors performed this study to investigate the efficacy and safety of a rosuvastatin (RSV)/amlodipine (AML) polypill compared with those of atorvastatin (ATV)/AML polypill. We included 259 patients from 21 institutions in Korea. Patients were randomly assigned to 1 of 3 treatment groups: RSV 10 mg/AML 5 mg, RSV 20 mg/AML 5 mg, or ATV 20 mg /AML 5 mg. The primary endpoint was the efficacy of the RSV 10.20 mg/AML 5 mg via percentage changes in LDL-C after 8 weeks of treatment, compared with the ATV 20 mg /AML 5 mg. There was a significant difference in the mean percentage change of LDL-C at 8 weeks between the RSV 10 mg/AML 5 mg and the ATV 20 mg/AML 5 mg (full analysis set [FAS]: -7.08%, 95% CI: -11.79 to -2.38, p = .0034, per-protocol analysis set [PPS]: -6.97%, 95% CI: -11.76 to -2.19, p = .0046). Also, there was a significant difference in the mean percentage change of LDL-C at 8 weeks between the RSV 20 mg/AML 5 mg and the ATV 20 mg/AML 5 mg (FAS: -10.13%, 95% CI: -15.41 to -4.84, p = .0002, PPS: -10.96%, 95% CI: -15.98 to -5.93, p < .0001). There was no significant difference in the adverse events rates between RSV 10 mg/AML 5 mg, RSV 20 mg/AML 5 mg, and ATV 20 mg/AML 5 mg. In conclusion, while maintaining safety, RSV 10 mg/AML 5 mg and the RSV 20 mg/AML 5 mg more effectively reduced LDL-C compared with the ATV 20 mg /AML 5 mg (Clinical trial: NCT03951207).


Asunto(s)
Dislipidemias , Hipertensión , Leucemia Mieloide Aguda , Humanos , Rosuvastatina Cálcica/efectos adversos , Atorvastatina/efectos adversos , Amlodipino/efectos adversos , Hipertensión/tratamiento farmacológico , Hipertensión/inducido químicamente , LDL-Colesterol , Dislipidemias/tratamiento farmacológico , Leucemia Mieloide Aguda/inducido químicamente , Método Doble Ciego , Resultado del Tratamiento
6.
Chem Sci ; 14(27): 7553-7558, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37449064

RESUMEN

In photocatalysis, metal-semiconductor hybrid structures have been proposed for ideal photocatalytic systems. In this study, we investigate the effect of morphology and surface nature of Pt cocatalysts on photocatalytic hydrogen evolution activity in Pt-tipped CdSe nanorods. Three distinct morphologies of Pt cocatalysts were synthesized and employed as visible light photocatalysts. The rough tips exhibit the highest activity, followed by the round and cubic tips. Kinetic investigations using transient absorption spectroscopy reveal that the cubic tips exhibit lower charge-separated states feasible for reacting with water and water reduction rates due to their defectless surface facets. In contrast, the rough tips show a similar charge-separation value but a two-fold higher surface reaction rate than the round tips, resulting in a significant enhancement of hydrogen evolution. These findings highlight the importance of rational design on metal cocatalysts in addition to the main semiconductor bodies for maximizing photocatalytic activities.

7.
Environ Pollut ; 329: 121582, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37062407

RESUMEN

The hazardous effects of air pollution on the human body are of grave concern, particularly the rising levels of 2.5 µm-particulate matter. Children are more susceptible to the lethal effects of particulate matter (PM) than adults. In this study, a case study of architectural renovation (ARCH-R) and facility renovation (FAC-R) was conducted in a school by focusing on the exit and entrance gates. In addition, the PM influx rate was evaluated. To evaluate the influx rate of PM, opening/closing recognition equipment and particle sensors were utilized. Following the renovation, the result was evaluated. During the daytime, the air curtain led to a reduction in the influx rate of PM of approximately 8% when the door was open. During the nighttime, it was confirmed that the fine dust influx rate was reduced through reinforcement of the door. However, regarding using these two measures in combination, it was confirmed that the concentration of PM increased in the corridor when the air curtain was operated while the door was closed. It was confirmed that both ARCH-R and FAC-R are necessary for controlling the influx of fine dust from the outdoor air. Appropriate operating guidelines should be provided for school operators.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Niño , Humanos , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Tamaño de la Partícula , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente , Polvo , Instituciones Académicas
8.
Angew Chem Int Ed Engl ; 62(22): e202303538, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-36997343

RESUMEN

Two covalent organic frameworks consisting of carbazolylene-ethynylene shape-persistent macrocycles with azine (MC-COF-1) or imine (MC-COF-2) linkages were synthesized via imine condensation. The obtained 2D frameworks are fully conjugated which imparts semiconducting properties. In addition, the frameworks showed high porosity with aligned accessible porous channels along the z axis, serving as an ideal platform for post-synthetic incorporation of I2 into the channels to enable electrical conductivity. The resulting MC-COF-1 showed an electrical conductivity up to 7.8×10-4  S cm-1 at room temperature upon I2 doping with the activation energy as low as 0.09 eV. Furthermore, we demonstrated that the electrical properties of both MC-COFs are switchable between electron-conducting and insulating states by simply implementing doping-regenerating cycles. The knowledge gained in this study opens new possibilities for the future development of tunable conductive 2D organic materials.

9.
Small ; 19(11): e2206988, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36642807

RESUMEN

Herein, the synthesis of Cu3 (HAB)x (TATHB)2-x (HAB: hexaaminobenzene, TATHB: triaminotrihydroxybenzene) is reported. Synthetic improvement of Cu3 (TATHB)2 leads to a more crystalline framework with higher electrical conductivity value than previously reported. The improved crystallinity and analogous structure between TATHB and HAB enable the synthesis of Cu3 (HAB)x (TATHB)2-x with ligand compositions precisely controlled by precursor ratios. The electrical conductivity is tuned from 4.2 × 10-8 to 2.9 × 10-5  S cm-1 by simply increasing the nitrogen content in the crystal lattice. Furthermore, computational calculation supports that the solid solution facilitates the band structure tuning. It is envisioned that the findings not only shed light on the ligand-dependent structure-property relationship but create new prospects in synthesizing multicomponent electrically conductive metal-organic frameworks (MOFs) for tailoring optoelectronic device applications.

10.
Fish Shellfish Immunol ; 131: 559-569, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36241004

RESUMEN

Peptidoglycan recognition proteins (PGRPs) belong to the pattern recognition receptor (PRR) family and are conserved from insects to mammals. PGRPs show specific binding abilities to peptidoglycans (PGNs) in various microbes. In this study, molecular and functional analyses of PGRP-SC2 from Amphiprion clarkii (AcPGRP-SC2) were conducted. The 492 bp ORF of AcPGRP-SC2 encoded a protein of 164 amino acids with a molecular weight of 17.58 kDa and pI of 8.9. The PGRP superfamily domain was identified from the protein sequence of AcPGRP-SC2 and sequence similarities were observed with homologous proteins. Quantitative polymerase chain reaction (qPCR) analysis revealed that AcPGRP-SC2 transcripts were ubiquitously expressed in all tested tissues, with high levels in the skin, and transcript expression was significantly modulated by immune stimulation with lipopolysaccharide (LPS), Polyinosinic:polycytidylic acid (poly I:C), and Vibrio harveyi post-immune challenge. Recombinant AcPGRP-SC2 with the maltose-binding protein fusion (rAcPGRP-SC2) was used to evaluate LPS-, PGN-, and bacterial-binding activities and to conduct bacterial agglutination assays, and the results demonstrated that AcPGRP-SC2 exhibited bacterial recognition, binding, and colonization abilities to a range of Gram-positive and Gram-negative bacterial strains. Moreover, rAcPGRP-SC2-pre-treated Fat Head Minnow (FHM) cells exhibited significant upregulation in NF-ĸB1, NF-ĸB2, and stat3 expression upon treatment with killed bacteria. Taken together, our findings suggest that AcPGRP-SC2 plays an important role in the immune response against microbial pathogens in A. clarkii.


Asunto(s)
Lipopolisacáridos , Perciformes , Animales , Estructura Molecular , Inmunidad Innata/genética , Proteínas Portadoras , Peptidoglicano/farmacología , Peptidoglicano/metabolismo , Mamíferos/metabolismo
11.
J Am Chem Soc ; 144(23): 10615-10621, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35653721

RESUMEN

The development of 2D electrically conductive metal-organic frameworks (EC-MOFs) has significantly expanded the scope of MOFs' applications into energy storage, electrocatalysis, and sensors. Despite growing interest in EC-MOFs, they often show low surface area and lack functionality due to the limited ligand motifs available. Herein we present a new EC-MOF using 2,3,8,9,14,15-hexahydroxyltribenzocyclyne (HHTC) linker and Cu nodes, featuring a large surface area. The MOF exhibits an electrical conductivity up to 3.02 × 10-3 S/cm and a surface area up to 1196 m2/g, unprecedentedly high for 2D EC-MOFs. We also demonstrate the utilization of alkyne functionality in the framework by postsynthetically hosting heterometal ions (e.g., Ni2+, Co2+). Additionally, we investigated particle size tunability, facilitating the study of size-property relationships. We believe that these results not only contribute to expanding the library of EC-MOFs but shed light on the new opportunities to explore electronic applications.


Asunto(s)
Estructuras Metalorgánicas , Alquinos , Conductividad Eléctrica , Electrónica
12.
Sci Rep ; 12(1): 8620, 2022 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-35597800

RESUMEN

Stem cells are attractive candidates for the regeneration of tissue and organ. Mesenchymal stem cells (MSCs) have been extensively investigated for their potential applications in regenerative medicine and cell therapy. For developing effective stem cell therapy, the mass production of consistent quality cells is required. The cell culture medium is the most critical aspect of the mass production of qualified stem cells. Classically, fetal bovine serum (FBS) has been used as a culture supplement for MSCs. Due to the undefined and heterologous composition of animal origin components in FBS, efforts to replace animal-derived components with non-animal-derived substances led to safe serum free media (SFM). Adipose derived mesenchymal stem cells (ADSCs) cultivated in SFM provided a more stable population doubling time (PDT) to later passage and more cells in a shorter time compared to FBS containing media. ADSCs cultivated in SFM had lower cellular senescence, lower immunogenicity, and higher genetic stability than ADSCs cultivated in FBS containing media. Differential expression analysis of mRNAs and proteins showed that the expression of genes related with apoptosis, immune response, and inflammatory response were significantly up-regulated in ADSCs cultivated in FBS containing media. ADSCs cultivated in SFM showed similar therapeutic efficacy in an acute pancreatitis mouse model to ADSCs cultivated in FBS containing media. Consideration of clinical trials, not only pre-clinical trial, suggests that cultivation of MSCs using SFM might offer more safe cell therapeutics as well as repeated administration due to low immunogenicity.


Asunto(s)
Células Madre Mesenquimatosas , Pancreatitis , Enfermedad Aguda , Animales , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Medios de Cultivo , Medio de Cultivo Libre de Suero , Ratones , Suero
13.
ACS Nano ; 16(2): 3145-3151, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35119816

RESUMEN

The emergence of 2D electrically conductive metal-organic frameworks (MOFs) has significantly expanded the scope of metal-organic framework applications from electrochemical energy storage to electronic devices. However, their potentials are not fully exploited due to limited accessibility to internal pores in stacked 2D structures. Herein we transform a 2D conjugated MOF into a 3D framework via postsynthetic pillar-ligand insertion. Cu-THQ was chosen due to its ability to adopt additional ligands at the axial positions at the copper nodes. Cu-THQ demonstrates that structural augmentation increases ion accessibility into internal pores, resulting in an increased gravimetric capacitance up to double that of the pristine counterpart. Beyond this, we believe that our findings can further be used to functionalize the existing 2D conductive MOFs to offer more opportunities in sensing, electronic, and energy-related applications by utilizing additional functions and increased accessibility from the pillars.

14.
Environ Pollut ; 294: 118616, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34883143

RESUMEN

As the demand for coffee has increased, by-product disposal has become a challenge to solve. Many studies are being conducted on how to use coffee waste as building materials to recycle it. In this study, the thermal performance and acoustic performance of a composite developed using bio-based microencapsulated phase change material (MPCM) and coffee waste were evaluated, and the composite was applied as building material. The coffee waste was successfully degreased with ethanol to produce composites, and removal of contaminants and oils was confirmed via scanning electron microscopy. In the phase change process of MPCM, an appropriate amount of thermal energy is absorbed and stored, and the temperature is maintained. MPCM was used in the mixture and the improved thermal performance was evaluated via differential scanning calorimetry analysis, revealing a latent heat of 3.8 J/g for MPCM content of 10%. Further, thermal imaging cameras revealed that an increase in the proportion of MPCM leads to a slower decrease in temperature because of the heat preserved by MPCM over time. In an acoustic performance evaluation, impedance tube test results showed different aspects depending on low, mid, and high-frequency bands. Specifically, at medium frequencies, which correspond to the range of noise generated in cafes, specimens fabricated using MPCM were confirmed to exhibit a higher sound absorption coefficient and an improved acoustic performance. Hence, the composite can be considered an eco-friendly building material with promising thermal and acoustic performance.


Asunto(s)
Café , Materiales de Construcción , Acústica , Reciclaje , Temperatura
15.
Fish Physiol Biochem ; 46(4): 1219-1227, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32146552

RESUMEN

Vertebrate ancient long (VAL)-opsin is a green-sensitive photoreceptor that shows high sequence similarity to vertebrate ancient opsin, which is considered to play a role in sexual maturation via gonadotropin-releasing hormone (GnRH); however, the role of VAL-opsin in vertebrate sexual maturity remains unclear. Therefore, we investigated the possible role of VAL-opsin in reproduction in the goldfish Carassius auratus under a state of GnRH inhibition. Goldfish were injected with recombinant VAL-opsin protein (0.5 µg/g body mass) and/or the GnRH antagonist cetrorelix (0.5 µg/fish), and changes in the mRNA expression levels of genes associated with goldfish reproduction were measured by quantitative polymerase chain reaction, including those involved in the hypothalamus-pituitary-gonad (HPG) axis, VAL-opsin, GnRH, the gonadotropins (GTHs) luteinizing hormone and follicle-stimulating hormone, and estrogen receptor (ER). Moreover, the fish were irradiated with a green light-emitting diode (520 nm) to observe the synergistic effect on the HPG axis with VAL-opsin. Green LED exposure significantly and slightly increased the VAL-opsin and GnRH levels, respectively; however, these effects were blocked in groups injected with cetrorelix at all time points. Cetrorelix significantly decreased the mRNA levels of GTHs and ER, whereas these hormones recovered by co-treatment with VAL-opsin. These results indicate that green LED is an effective light source to promote the expression of sex hormones in fish. Moreover, VAL-opsin not only affects activity of the HPG axis but also appears to act on the pituitary gland directly to stimulate a new sexual maturation pathway that promotes the secretion of GTHs independent of GnRH.


Asunto(s)
Opsinas de los Conos/fisiología , Carpa Dorada/fisiología , Hormona Liberadora de Gonadotropina/fisiología , Redes y Vías Metabólicas/fisiología , Reproducción/fisiología , Animales , Encéfalo/metabolismo , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Gónadas/fisiología , Antagonistas de Hormonas/administración & dosificación , Hipotálamo/fisiología , Fotoperiodo , Hipófisis/fisiología , ARN Mensajero/metabolismo , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Proteínas Recombinantes
16.
Cells ; 9(12)2020 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-33419308

RESUMEN

Immune complexes containing citrullinated fibrinogen are present in the sera and synovium of rheumatoid arthritis patients and potentially contribute to synovitis. However, fibrinogen can inhibit the osteoclastogenesis of precursor cells. We investigated the direct effect of citrullinated fibrinogen on osteoclastogenesis to understand the role of citrullination on bone erosion of rheumatoid arthritis patients. We evaluated the fibrinogen citrullination sites using mass spectrometry and quantified osteoclast-related protein and gene expression levels by Western blotting, microarray, and real-time polymerase chain reaction. Differences in spectral peaks were noted between fibrinogen and citrullinated fibrinogen at five sites in α-chains, two sites in ß-chains, and one site in a γ-chain. Transcriptome changes induced by fibrinogen and citrullinated fibrinogen were identified and differentially expressed genes grouped into three distinctive modules. Fibrinogen was then citrullinated in vitro using peptidylarginine deiminase. When increasing doses of soluble fibrinogen and citrullinated fibrinogen were applied to human CD14+ monocytes, citrullination restored osteoclastogenesis-associated changes, including NF-ATc1 and ß3-integrin. Finally, citrullination rescued the number of osteoclasts by restoring fibrinogen-induced suppression of osteoclastogenesis. Taken together, the results indicate that the inhibitory function of fibrinogen on osteoclastogenesis is reversed by citrullination and suggest that citrullinated fibrinogen may contribute to erosive bone destruction in rheumatoid arthritis.


Asunto(s)
Artritis Reumatoide/metabolismo , Huesos/metabolismo , Citrulinación , Fibrinógeno/química , Osteogénesis , Animales , Resorción Ósea , Bovinos , Diferenciación Celular , Citrulina/química , Fibrinógeno/metabolismo , Humanos , Inflamación , Integrina beta3/metabolismo , Leucocitos Mononucleares/citología , Receptores de Lipopolisacáridos/metabolismo , Factores de Transcripción NFATC/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteoclastos/metabolismo , Líquido Sinovial/metabolismo
17.
Chem Asian J ; 15(2): 253-265, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31823512

RESUMEN

Conversion of carbon dioxide (CO2 ) into value-added chemicals has attracted much attention because it can not only resolve global warming issues by reducing CO2 accumulation in the atmosphere, but also produce renewable hydrocarbon fuels that are important feedstocks for the chemical industry. Among the diverse approaches reported, CO2 reduction via electro- and photocatalytic methods is at the center of topics due to potential engineering of reaction performance through rational design of catalyst features. In this Minireview, we highlight recent strategies for designing nanoparticles to maximize the reaction efficiency and selectivity; from a materials viewpoint, these strategies can provide critical information to guide future research directions.

19.
Int J Rheum Dis ; 22(5): 905-912, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30860673

RESUMEN

AIM: To investigate the clinical implications of a genetic polymorphism in glycoprotein 96 (GP96), by analyzing the association between the genotype and haplotype of GP96 with systemic lupus erythematosus (SLE). METHOD: We analyzed cell-surface expression of GP96 in peripheral blood mononuclear cells (PBMCs) and serum titer of anti-GP96 antibody of SLE patients. Single nucleotide polymorphisms and deletion mutants of GP96 were detected by two-dimensional gene scanning (TDGS). Odds ratios with 95% confidence intervals (CI) were determined for each genotype and haplotype through the chi-square test. RESULTS: In total, 216 Korean SLE patients and 215 age- and sex-matched healthy controls were enrolled. In SLE patients, as opposed to healthy controls, cell-surface expression of GP96 among human leukocyte antigen-DR+ PBMCs (76.4% vs 45.5%, respectively, P < 0.001) and serum anti-GP96 antibody titers (0.98 vs 0.50, respectively, P = 0.012) increased. TDGS revealed six polymorphic sites in GP96, two of which were significantly associated with SLE (exon 1, g.-7C>G, odds ratio [OR] 1.78, 95% CI 1.16-2.75, P = 0.009; exon 17, g.17009_17011del, OR 1.76, 95% CI 1.18-2.64, P = 0.006). Two haplotypes (121111, 211212) were strongly associated with SLE (OR 8.92, 95% CI 1.10-72.6, P = 0.041; OR 3.03, 95% CI 1.22-7.50, P = 0.017, respectively) and specific clinical manifestations (discoid rash, arthritis, renal disorder, neurologic disorder, and hematologic disorder). Haplotype-based analysis revealed a stronger association between GP96 and SLE than did genotype-based analysis. CONCLUSION: The two polymorphisms, each in exons 1 and 17 of GP96 are potential genetic risk factors of SLE. Two haplotypes 121111 and 211212 are related to not only SLE but also specific clinical manifestations.


Asunto(s)
Lupus Eritematoso Sistémico/genética , Glicoproteínas de Membrana/genética , Polimorfismo de Nucleótido Simple , Eliminación de Secuencia , Adulto , Estudios de Casos y Controles , Exones , Femenino , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Persona de Mediana Edad , Fenotipo , Medición de Riesgo , Factores de Riesgo , Adulto Joven
20.
Nanoscale Adv ; 1(10): 3948-3956, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-36132117

RESUMEN

Recently, quantum dots (QDs) have often garnered significant attention and have been employed for various applications. Nevertheless, most conventional devices utilize a glass substrate and/or brittle substrate, which is not compatible with next-generation wearable electronics. A suitable method for devising conductive and flexible free-standing platforms that can be combined with various kinds of QDs is thus in great need for next-generation wearable electronics. In this work, we introduce a universal and simple method to coat QDs on carbon nanofibers (CNFs) by a dip-coating process, where many kinds of QDs can be well decorated on the surface of CNFs. As one potential application among many, QD-coated CNFs were examined for their photocatalytic applications and characterization. As a result, it was found that the best performance of CdSe QD-coated CNFs for hydrogen production was 3.8 times higher than that of only QDs with the same 1 mg of QDs. This is an early report on fabricating various kinds of QD-coated CNFs, which can be extended to a myriad set of applications.

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