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1.
J Obes Metab Syndr ; 33(1): 54-63, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38204191

RESUMO

Background: Pre-diabetes can develop into type 2 diabetes mellitus, but can prevented by regular exercise. However, the outcomes when combining unsupervised Kinect-based mixed-reality (KMR) exercise with continuous glucose monitoring (CGM) remain unclear. Therefore, this single-arm pilot trial examined changes in blood glucose (BG) concentrations over 672 hours (4 weeks), including a 2-week period of KMR exercise and CGM in individuals with pre-diabetes. Methods: This was a pre-and post-treatment case-control study with nine participants. General questionnaires were administered and body composition, fasting BG concentrations, and 2-hour oral glucose tolerance test (2-OGTT) results were measured pre-and post-treatment. Weekly average glucose concentrations, hyperglycemia rate, hypoglycemia rate, average glucose concentration over time, amount of physical activity, amount of food intake, and pre- and postprandial BG (immediately and 30, 60, 90, and 120 minutes after lunch) were measured over 4 weeks (pre-test, exercise, and post -test weeks). Glucose concentrations were measured before exercising, between sets, and 30 and 60 minutes after exercise during the 2 weeks of unsupervised exercise (3 days/week). Results: In all participants, body mass index (27.16±2.92 kg/m2), fasting BG (108.00±7.19 mg/dL), 2-OGTT (162.56±18.12 mg/dL), hyperglycemia rate (P=0.040), and 90-minute postprandial BG (P=0.035) were significantly reduced during the 2 exercise weeks, and the 2-OGTT result (P=0.044) and diastolic blood pressure (DBP) (P=0.046) were significantly reduced at the post -test as compared with the pre-test. Conclusion: This study found that 2 weeks of unsupervised KMR exercise reduced 2-OGTT, DBP, hyperglycemia rate, and 90-minute postprandial BG concentration. We believed this effect could be identified more clearly in studies involving a larger number of participants and longer durations of exercise.

2.
J Phys Chem C Nanomater Interfaces ; 127(42): 20700-20709, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37908742

RESUMO

Alloys of gallium with transition metals have recently received considerable attention for their applications in microelectronics and catalysis. Here, we investigated the initial stages of the Ga-Cu alloy formation on Cu(111) and Cu(001) surfaces using scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and low energy electron diffraction (LEED). The results show that Ga atoms deposited using physical vapor deposition readily intermix with the Cu surface, leading to a random distribution of the Ga and Cu atoms within the surface layer, on both terraces and monolayer-thick islands formed thereon. However, as the Ga coverage increases, several ordered structures are formed. The (√3×√3)R30° structure is found to be thermodynamically most stable on Cu(111). This structure remains after vacuum annealing at 600 K, independent of the initial Ga coverage (varied between 0.5 and 3 monolayers), indicating a self-limited growth of the Ga-Cu alloy layer, with the rest of the Ga atoms migrating into the Cu crystal. For Ga deposited on Cu(001), we observed a (1 × 5)-reconstructed surface, which has never been observed for surface alloys on Cu(001). The experimental findings were rationalized on the basis of density functional theory (DFT) calculations, which provided structural models for the most stable surface Ga-Cu alloys on Cu(111) and Cu(001). The study sheds light on the complex interaction of Ga with transition metal surfaces and the interfaces formed thereon that will aid in a better understanding of surface alloying and chemical reactions on the Ga-based alloys.

3.
Nat Commun ; 14(1): 4649, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532720

RESUMO

Gallium-containing alloys have recently been reported to hydrogenate CO2 to methanol at ambient pressures. However, a full understanding of the Ga-promoted catalysts is still missing due to the lack of information about the surface structures formed under reaction conditions. Here, we employed near ambient pressure scanning tunneling microscopy and x-ray photoelectron spectroscopy to monitor the evolution of well-defined Cu-Ga surfaces during CO2 hydrogenation. We show the formation of two-dimensional Ga(III) oxide islands embedded into the Cu surface in the reaction atmosphere. The islands are a few atomic layers in thickness and considerably differ from bulk Ga2O3 polymorphs. Such a complex structure, which could not be determined with conventional characterization methods on powder catalysts, should be used for elucidating the reaction mechanism on the Ga-promoted metal catalysts.

4.
Nat Sci Sleep ; 15: 59-67, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36879665

RESUMO

Purpose: The commercialization of sleep activity tracking devices has made it possible to manage sleep quality at home. However, it is necessary to verify the reliability and accuracy of wearable devices through comparison with polysomnography (PSG), which is the standard for tracking sleep activity. This study aimed to monitor overall sleep activity using Fitbit Inspire 2™ (FBI2) and to evaluate its performance and effectiveness through PSG under the same conditions. Patients and Methods: We compared the FBI2 and PSG data of nine participants (four male and five female participants; average age, 39 years) without severe sleeping problems. The participants wore FBI2 continuously for 14 days, considering the period of adaptation to the device. FBI2 and PSG sleep data were compared using paired t-tests, Bland-Altman plots, and epoch-by-epoch analysis for 18 samples by pooling data from two replicates. Results: The average values for each sleep stage obtained from FBI2 and PSG showed significant differences in the total sleep time (TST), deep sleep, and rapid eye motion (REM). In the Bland-Altman analysis, TST (P = 0.02), deep sleep (P = 0.05), and REM (P = 0.03) were significantly overstated in FBI2 compared to PSG. In addition, time in bed, sleep efficiency, and wake after sleep onset were overestimated, while light sleep was underestimated. However, these differences were not statistically significant. FBI2 showed a high sensitivity (93.9%) and low specificity (13.1%), with an accuracy of 76%. The sensitivity and specificity of each sleep stage was 54.3% and 62.3%, respectively, for light sleep, 84.8% and 50.1%, respectively, for deep sleep, and 86.4% and 59.1%, respectively for REM sleep. Conclusion: The use of FBI2 as an objective tool for measuring sleep in daily life can be considered appropriate. However, further research is warranted on its application in participants with sleep-wake problems.

5.
Nano Lett ; 23(11): 5373-5380, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-36930862

RESUMO

Excitation of hot electrons by energy dissipation under exothermic chemical reactions on metal catalyst surfaces occurs at both solid-gas and solid-liquid interfaces. Despite extensive studies, a comparative operando study directly comparing electronic excitation by electronically nonadiabatic interactions at solid-gas and solid-liquid interfaces has not been reported. Herein, on the basis of our in situ techniques for monitoring energy dissipation as a chemicurrent using a Pt/n-Si nanodiode sensor, we observed the generation of hot electrons in both gas and liquid phases during H2O2 decomposition. As a result of comparing the current signal and oxygen evolution rate in the two phases, surprisingly, the efficiency of reaction-induced excitation of hot electrons increased by ∼100 times at the solid-liquid interface compared to the solid-gas interface. The boost of hot electron excitation in the liquid phase is due to the presence of an ionic layer lowering the potential barrier at the junction for transferring hot electrons.

6.
J Phys Chem Lett ; 13(40): 9435-9448, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36194546

RESUMO

Understanding the role of energy dissipation and charge transfer under exothermic chemical reactions on metal catalyst surfaces is important for elucidating the fundamental phenomena at solid-gas and solid-liquid interfaces. Recently, many surface chemistry studies have been conducted on the solid-liquid interface, so correlating electronic excitation in the liquid-phase with the reaction mechanism plays a crucial role in heterogeneous catalysis. In this review, we introduce the detection principle of electron transfer at the solid-liquid interface by developing cutting-edge technologies with metal-semiconductor Schottky nanodiodes. The kinetics of hot electron excitation are well correlated with the reaction rates, demonstrating that the operando method for understanding nonadiabatic interactions is helpful in studying the reaction mechanism of surface molecular processes. In addition to the detection of hot electrons excited by a catalytic reaction, we highlight recent results on how the transfer of the hot electrons influences surface chemical and photoelectrochemical reactions.

7.
Diabetes Metab J ; 46(2): 337-348, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35052026

RESUMO

BACKGROUND: We investigated the antidiabetic effects of DA-1241, a novel G protein-coupled receptor (GPR) 119 agonist, in vitro and in vivo. METHODS: DA-1241 was administrated to high-fat diet (HFD)-fed C57BL/6J mice for 12 weeks after hyperglycaemia developed. Oral/intraperitoneal glucose tolerance test and insulin tolerance test were performed. Serum insulin and glucagon-like peptide-1 (GLP-1) levels were measured during oral glucose tolerance test. Insulinoma cell line (INS-1E) cells and mouse islets were used to find whether DA-1241 directly stimulate insulin secretion in beta cell. HepG2 cells were used to evaluate the gluconeogenesis and autophagic process. Autophagic flux was evaluated by transfecting microtubule-associated protein 1 light chain 3-fused to green fluorescent protein and monomeric red fluorescent (mRFP-GFP-LC3) expression vector to HepG2 cells. RESULTS: Although DA-1241 treatment did not affect body weight gain and amount of food intake, fasting blood glucose level decreased along with increase in GLP-1 level. DA-1241 improved only oral glucose tolerance test and showed no effect in intraperitoneal glucose tolerance test. No significant effect was observed in insulin tolerance test. DA-1241 did not increase insulin secretion in INS-1E cell and mouse islets. DA-1241 reduced triglyceride content in the liver thereby improved fatty liver. Additionally, DA-1241 reduced gluconeogenic enzyme expression in HepG2 cells and mouse liver. DA-1241 reduced autophagic flow in HepG2 cells. CONCLUSION: These findings suggested that DA-1241 augmented glucose-dependent insulin release via stimulation of GLP-1 secretion, and reduced hepatic gluconeogenesis, which might be associated with autophagic blockage, leading to improved glycaemic control.


Assuntos
Diabetes Mellitus Experimental , Hiperglicemia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Peptídeo 1 Semelhante ao Glucagon , Gluconeogênese , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Insulina , Secreção de Insulina , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
8.
Arch Craniofac Surg ; 22(5): 239-246, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34732035

RESUMO

BACKGROUND: Bone grafts can provide an optimal environment for permanent tooth to erupt and enhance the stability of the alveolar maxilla. Although autologous bone is an optimal source for osteogenesis, its inevitable donor site morbidity has led to active research on bone substitutes. This study was designed to evaluate the safety and feasibility of using biphasic calcium phosphate (BCP; Osteon) as a bone substitute in dogs. METHODS: Bilateral third and fourth premolars of four 15-week-old mongrel dogs were used. All teeth were extracted except the third premolar of the right mandible, which was used as a control. After extraction of the premolars, each dog was administered BCP (Osteon), demineralized bone matrix (DBM; DBX), and no graft in the hollow sockets of the right fourth premolar, left fourth premolar, and left third premolar, respectively. Radiographs were taken at 2-week intervals to check for tooth eruption. After 8 weeks, each dog was sacrificed, and tooth and bone biopsies were performed to check for the presence of tooth and bone substitute particle remnants. RESULTS: Four weeks after the operation, permanent tooth eruptions had started at all the extraction sites in each dog. Eight weeks after the operation, all teeth had normally erupted, and histological examination revealed BCP particles at the right fourth premolar. CONCLUSION: In all four dogs, no delay in the eruption of the teeth or shape disfigurement of permanent teeth was observed on gross inspection and radiologic evaluation. On histological examination, most of the BCP and DBM were replaced by new bone. Bone substitutes can be used as graft materials in patients with alveolar clefts.

9.
Nat Commun ; 12(1): 40, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397946

RESUMO

Interaction between metal and oxides is an important molecular-level factor that influences the selectivity of a desirable reaction. Therefore, designing a heterogeneous catalyst where metal-oxide interfaces are well-formed is important for understanding selectivity and surface electronic excitation at the interface. Here, we utilized a nanoscale catalytic Schottky diode from Pt nanowire arrays on TiO2 that forms a nanoscale Pt-TiO2 interface to determine the influence of the metal-oxide interface on catalytic selectivity, thereby affecting hot electron excitation; this demonstrated the real-time detection of hot electron flow generated under an exothermic methanol oxidation reaction. The selectivity to methyl formate and hot electron generation was obtained on nanoscale Pt nanowires/TiO2, which exhibited ~2 times higher partial oxidation selectivity and ~3 times higher chemicurrent yield compared to a diode based on Pt film. By utilizing various Pt/TiO2 nanostructures, we found that the ratio of interface to metal sites significantly affects the selectivity, thereby enhancing chemicurrent yield in methanol oxidation. Density function theory (DFT) calculations show that formation of the Pt-TiO2 interface showed that selectivity to methyl formate formation was much larger in Pt nanowire arrays than in Pt films because of the different reaction mechanism.

10.
ACS Nano ; 14(12): 16392-16413, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33210917

RESUMO

Modern surface science faces two major challenges, a materials gap and a pressure gap. While studies on single crystal surface in ultrahigh vacuum have uncovered the atomic and electronic structures of the surface, the materials and environmental conditions of commercial catalysis are much more complicated, both in the structure of the materials and in the accessible pressure range of analysis instruments. Model systems and operando surface techniques have been developed to bridge these gaps. In this Review, we highlight the current trends in the development of the surface characterization techniques and methodologies in more realistic environments, with emphasis on recent research efforts at the Korea Advanced Institute of Science and Technology. We show principles and applications of the microscopic and spectroscopic surface techniques at ambient pressure that were used for the characterization of atomic structure, electronic structure, charge transport, and the mechanical properties of catalytic and energy materials. Ambient pressure scanning tunneling microscopy and X-ray photoelectron spectroscopy allow us to observe the surface restructuring that occurs during oxidation, reduction, and catalytic processes. In addition, we introduce the ambient pressure atomic force microscopy that revealed the morphological, mechanical, and charge transport properties that occur during the catalytic and energy conversion processes. Hot electron detection enables the monitoring of catalytic reactions and electronic excitations on the surface. Overall, the information on the nature of catalytic reactions obtained with operando spectroscopic and microscopic techniques may bring breakthroughs in some of the global energy and environmental problems the world is facing.

11.
ACS Nano ; 14(7): 8335-8342, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32539337

RESUMO

The interfacial effect between a metal catalyst and its various supporting transition metal oxides on the catalytic activity of heterogeneous catalysis has been extensively explored; engineering interfacial sites of metal supported on metal oxide has been found to influence catalytic performance. Here, we investigate the interfacial effect of Pt nanowires (NWs) vertically and alternatingly stacked with titanium dioxide (TiO2) or cobalt monoxide (CoO) NWs, which exhibit a strong metal-support interaction under carbon monoxide (CO) oxidation. High-resolution nanotransfer printing based on nanoscale pattern replication and e-beam evaporation were utilized to obtain the Pt NWs cross-stacked on the CoO or TiO2 NW on the silicon dioxide (SiO2) substrate with varying numbers of nanowires. The morphology and interfacial area were precisely determined by means of atomic force microscopy and scanning electron microscopy. The cross-stacked Pt/TiO2 NW and Pt/CoO NW catalysts were estimated with CO oxidation under 40 Torr CO and 100 Torr O2 from 200 to 240 °C. Higher catalytic activity was found on the Pt/CoO NW catalyst than on Pt/TiO2 NWs and Pt NWs, which indicates the significance of nanoscale metal-oxide interfaces. As the number of nanowire layers increased, the catalytic activity became saturated. Our study demonstrates the interfacial role of nanoscale metal-oxide interfaces under CO oxidation, which has intriguing applications in the smart design of catalytic materials.

12.
Cells ; 9(5)2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403252

RESUMO

Chromatin remodeling, including histone modification, chromatin (un)folding, and nucleosome remodeling, is a significant transcriptional regulation mechanism. By these epigenetic modifications, transcription factors and their regulators are recruited to the promoters of target genes, and thus gene expression is controlled through either transcriptional activation or repression. The Mat1-mediated transcriptional repressor (MMTR)/DNA methyltransferase 1 (DNMT1)-associated protein (Dmap1) is a transcription corepressor involved in chromatin remodeling, cell cycle regulation, DNA double-strand break repair, and tumor suppression. The Tip60-p400 complex proteins, including MMTR/Dmap1, interact with the oncogene Myc in embryonic stem cells (ESCs). These proteins interplay with the stem cell-related proteome networks and regulate gene expressions. However, the detailed mechanisms of their functions are unknown. Here, we show that MMTR/Dmap1, along with other Tip60-p400 complex proteins, bind the promoters of differentiation commitment genes in mouse ESCs. Hence, MMTR/Dmap1 controls gene expression alterations during differentiation. Furthermore, we propose a novel mechanism of MMTR/Dmap1 function in early stage lineage commitment of mouse ESCs by crosstalk with the polycomb group (PcG) proteins. The complex controls histone mark bivalency and transcriptional poising of commitment genes. Taken together, our comprehensive findings will help better understand the MMTR/Dmap1-mediated transcriptional regulation in ESCs and other cell types.


Assuntos
Linhagem da Célula , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas do Grupo Polycomb/metabolismo , Proteínas Repressoras/metabolismo , Animais , Diferenciação Celular , Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Histonas/metabolismo , Humanos , Lisina/metabolismo , Lisina Acetiltransferase 5/metabolismo , Metilação , Camundongos , Camundongos SCID , Modelos Biológicos , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Repressoras/química , Transativadores/metabolismo
13.
J Transl Med ; 18(1): 100, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093722

RESUMO

BACKGROUND: Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) has been emerging as a significant health issue worldwide. This study aimed to systemically assess the prevalence of CFS/ME in various aspects of analyses for precise assessment. METHODS: We systematically searched prevalence of CFS/ME from public databases from 1980 to December 2018. Data were extracted according to 7 categories for analysis: study participants, gender and age of the participants, case definition, diagnostic method, publication year, and country of the study conducted. Prevalence data were collected and counted individually for studies adopted various case definitions. We analyzed and estimated prevalence rates in various angles: average prevalence, pooled prevalence and meta-analysis of all studies. RESULTS: A total of 1291 articles were initially identified, and 45 articles (46 studies, 56 prevalence data) were selected for this study. Total 1085,976 participants were enrolled from community-based survey (540,901) and primary care sites (545,075). The total average prevalence was 1.40 ± 1.57%, pooled prevalence 0.39%, and meta-analysis 0.68% [95% CI 0.48-0.97]. The prevalence rates were varied by enrolled participants (gender, study participants, and population group), case definitions and diagnostic methods. For example, in the meta-analysis; women (1.36% [95% CI 0.48-0.97]) vs. men (0.86% [95% CI 0.48-0.97]), community-based samples (0.76% [95% CI 0.53-1.10]) vs. primary care sites (0.63% [95% CI 0.37-1.10]), adults ≥ 18 years (0.65% [95% CI 0.43-0.99]) vs. children and adolescents < 18 years (0.55% [95% CI 0.22-1.35]), CDC-1994 (0.89% [95% CI 0.60-1.33]) vs. Holmes (0.17% [95% CI 0.06-0.49]), and interviews (1.14% [95% CI 0.76-1.72]) vs. physician diagnosis (0.09% [95% CI 0.05-0.13]), respectively. CONCLUSIONS: This study comprehensively estimated the prevalence of CFS/ME; 0.89% according to the most commonly used case definition CDC-1994, with women approximately 1.5 to 2 folds higher than men in all categories. However, we observed the prevalence rates are widely varied particularly by case definitions and diagnostic methods. An objective diagnostic tool is urgently required for rigorous assessment of the prevalence of CFS/ME.


Assuntos
Síndrome de Fadiga Crônica , Adolescente , Adulto , Criança , Síndrome de Fadiga Crônica/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Inquéritos e Questionários
14.
Asia Pac J Clin Nutr ; 28(4): 837-844, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826382

RESUMO

BACKGROUND AND OBJECTIVES: Several studies have suggested that abnormal levels of serum cholesterol may be a major risk factor for osteoarthritis. However, no studies have been conducted to prevent osteoarthritis under controlled conditions of serum cholesterol. This study aimed to examine the relationship of sociodemographic and anthropometric characteristics, and nutrient and food intakes with osteoarthritis prevalence in Korean elderly subjects with controlled dyslipidaemia. METHODS AND STUDY DESIGN: This study included 314 subjects aged ≥65 years who were diagnosed and treated for dyslipidaemia (data from the Seventh Korea National Health and Nutrition Examination Survey, 2016). Among them, 108 were also diagnosed with osteoarthritis. Sociodemographic, health, and nutritional data were analysed. RESULTS: Osteoarthritis prevalence was higher in females, highereducated subjects, unmarried subjects, non-smokers, and subjects with high body mass index (p<0.05). After adjusting for the multiple variables, the non-osteoarthritis group had significantly higher vitamin C intake (132±11.0 vs 93.1±11.1 mg/day), fish intake (172±30.0 vs 79.0±12.9 g/day), and seaweed intake (93.7±19.3 vs 38.3±13.4 mg/day) than the osteoarthritis group. Furthermore, the lowest vitamin C, fish, seaweed intake group (quartile 1) each had 3.20, 2.76, 9.93 times higher risk of osteoarthritis than the highest vitamin C, fish, seaweed intake group (quartile 4) (p<0.05). CONCLUSIONS: Among Korean elderly subjects with controlled dyslipidaemia, those with osteoarthritis had lower vitamin C, fish, seaweed intakes than those without osteoarthritis. Although our results do not prove that low vitamin C, fish, seaweed intakes cause osteoarthritis, such relationship is worth exploring for a preventive perspective.


Assuntos
Antropometria , Dislipidemias/tratamento farmacológico , Ingestão de Alimentos , Estado Nutricional , Osteoartrite/epidemiologia , Osteoartrite/etiologia , Idoso , Estudos Transversais , Feminino , Humanos , Hipolipemiantes/uso terapêutico , Masculino , Inquéritos Nutricionais , Fatores Socioeconômicos
15.
Chem Commun (Camb) ; 55(64): 9503-9506, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31328745

RESUMO

The strong metal-oxide interaction of platinum nanoparticles (PtNPs) deposited on two types of cobalt oxides, CoO and Co3O4, was investigated using CO oxidation. Two different sizes of PtNPs as well as arc-plasma-deposited (APD) PtNPs without a capping layer were used to reveal the effect of metal-oxide interfaces on catalytic activity. An enhanced catalytic activity was observed on the PtNPs on the Co3O4 substrate, which was ascribed to the reducible support and to the interfacial sites.

16.
Biomater Sci ; 7(7): 2907-2919, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31089612

RESUMO

Although the design of more biocompatible polymeric implants has been studied for decades, their intended functionality continues to be impaired by the response of the host tissue to foreign bodies at the tissue-implant interface. In particular, the formation and contracture of fibrous capsules prevent the intimate integration of an implant with surrounding tissues, which leads to structural deformation of the implants and persistent discomfort and pain. We report a new surface nano-engineered silicone implant that reduces fibrous capsule formation and improves the biocompatibility of it via sputtering-based plasma immersion ion implantation (S-PIII). This technique can introduce biologically compatible tantalum (Ta) on the silicone surface to produce a Ta-implanted skin layer (<60 nm thick) as well as generate either smooth (Smooth/Ta silicone) or nano-textured (Nano/Ta silicone) surface morphologies. The biologically inert chemical structure and strong hydrophobic surface characteristics of bare silicone are substantially ameliorated after Ta ion implantation. In particular, the Nano/Ta silicone implant's combination of surface nano-texturing as a physical cue and the Ta-implanted layer as a chemical cue was found to be very effective at achieving outstanding hydrophilicity and fibroblast affinity compared to the bare and Smooth/Ta silicone implants. In a mouse in vivo study conducted for 8 weeks, the Nano/Ta silicone implant inhibited fibrous capsule formation and contracture on its surface better than the bare silicone based on an analysis of the number of macrophages, myofibroblast differentiation and activation, collagen density, and thickness of fibrous capsules.


Assuntos
Engenharia , Nanotecnologia , Próteses e Implantes , Silicones/química , Tantálio/química , Animais , Fibroblastos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fenômenos Mecânicos , Ativação Plaquetária/efeitos dos fármacos , Adesividade Plaquetária/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Silicones/farmacologia , Propriedades de Superfície
17.
Artigo em Inglês | MEDLINE | ID: mdl-31118964

RESUMO

AIM: We investigated the distribution of cold hypersensitivity in the hands and feet (CHHF) and examined the association between CHHF and health-related quality of life (HRQOL) among Koreans. METHODS: Stratified multistage sampling was used for random selection of 2,201 adults. HRQOL was assessed using the Short-Form 12-Item Health Survey (SF-12). Cold hypersensitivity was measured using a new self-report questionnaire to score the extent of cold sensation in their hands, feet, and abdomen using a 7-point scale. The correlation between CHHF and HRQOL was analysed using multiple regression analysis. RESULTS: Cold hypersensitivity was present in the hands of 21.6%, the feet of 23.0%, and the abdomen in 22.5% of participants. Cold hypersensitivity in the hands and feet was observed in 17.9%, at least one body part (hands, feet, or abdomen) in 34.2%, and all three body regions in 12.3% of participants. The prevalence of cold hypersensitivity was significantly higher among women than among men, irrespective of the involved body part. Cold hypersensitivity scores in the hands and feet correlated negatively with body mass index, but not with age. The physical component summary (PCS) and mental component summary (MCS) of the SF-12 were both significantly lower in women with than in those without CHHF. Among men, only the PCS was significantly lower in the CHHF group. Multiple regression analysis, adjusted for sociodemographic variables, age, sex, and body mass index (BMI), confirmed that CHHF had negative effects on PCS and MCS. CONCLUSIONS: CHHF is more common in women and in individuals with a lower BMI. CHHF has an independent negative effect on HRQOL.

18.
Chem Commun (Camb) ; 54(97): 13734-13737, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30456410

RESUMO

We present a straightforward approach for fabricating AuPd nanocatalysts based on self-assembled block copolymer nanopatterning. CO oxidation was carried out on AuPd alloy nanoparticles and the activity increased with increasing Pd content; this synergistic activity can be precisely tuned by varying the chemical composition. Theoretical calculations suggest that Pd clusters are required to bind and dissociate O2 for oxidation of coadsorbed CO molecules. Our results suggest that the geometric configuration of the Pd atoms on the surface are a key factor in the catalytic activity.

19.
Sci Adv ; 4(7): eaat3151, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30027118

RESUMO

The origin of the synergistic catalytic effect between metal catalysts and reducible oxides has been debated for decades. Clarification of this effect, namely, the strong metal-support interaction (SMSI), requires an understanding of the geometric and electronic structures of metal-metal oxide interfaces under operando conditions. We show that the inherent lattice mismatch of bimetallic materials selectively creates surface segregation of subsurface metal atoms. Interfacial metal-metal oxide nanostructures are then formed under chemical reaction environments at ambient pressure, which thus increases the catalytic activity for the CO oxidation reaction. Our in situ surface characterizations using ambient-pressure scanning tunneling microscopy and ambient-pressure x-ray photoelectron spectroscopy exhibit (i) a Pt-skin layer on the Pt-Ni alloyed surface under ultrahigh vacuum, (ii) selective Ni segregation followed by the formation of NiO1-x clusters under oxygen gas, and (iii) the coexistence of NiO1-x clusters on the Pt-skin during the CO oxidation reaction. The formation of interfacial Pt-NiO1-x nanostructures is responsible for a highly efficient step in the CO oxidation reaction. Density functional theory calculations of the Pt3Ni(111) surface demonstrate that a CO molecule adsorbed on an exposed Pt atom with an interfacial oxygen from a segregated NiO1-x cluster has a low surface energy barrier of 0.37 eV, compared with 0.86 eV for the Pt(111) surface.

20.
BMC Genomics ; 19(1): 481, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921221

RESUMO

BACKGROUND: Face morphology is strongly determined by genetic factors. However, only a small number of genes related to face morphology have been identified to date. Here, we performed a two-stage genome-wide association study (GWAS) of 85 face morphological traits in 7569 Koreans (5643 in the discovery set and 1926 in the replication set). RESULTS: In this study, we analyzed 85 facial traits, including facial angles. After discovery GWAS, 128 single nucleotide polymorphisms (SNPs) showing an association of P < 5 × 10- 6 were selected to determine the replication of the associations, and meta-analysis of discovery GWAS and the replication analysis resulted in five genome-wide significant loci. The OSR1-WDR35 [rs7567283, G allele, beta (se) = -0.536 (0.096), P = 2.75 × 10- 8] locus was associated with the facial frontal contour; the HOXD1-MTX2 [rs970797, A allele, beta (se) = 0.015 (0.003), P = 3.97 × 10- 9] and WDR27 [rs3736712, C allele, beta (se) = 0.293 (0.048), P = 8.44 × 10- 10] loci were associated with eye shape; and the SOX9 [rs2193054, C allele, beta (se) (ln-transformed) = -0.007 (0.001), P = 6.17 × 10- 17] and DHX35 [rs2206437, A allele, beta (se) = -0.283 (0.047), P = 1.61 × 10- 9] loci were associated with nose shape. WDR35 and SOX9 were related to known craniofacial malformations, i.e., cranioectodermal dysplasia 2 and campomelic dysplasia, respectively. In addition, we found three independent association signals in the SOX9 locus, and six known loci for nose size and shape were replicated in this study population. Interestingly, four SNPs within these five face morphology-related loci showed discrepancies in allele frequencies among ethnic groups. CONCLUSIONS: We identified five novel face morphology loci that were associated with facial frontal contour, nose shape, and eye shape. Our findings provide useful genetic information for the determination of face morphology.


Assuntos
Loci Gênicos/genética , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único/genética , Idoso , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Proteínas de Homeodomínio/genética , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Fatores de Transcrição SOX9/genética
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