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1.
Int J Biol Macromol ; 261(Pt 1): 129670, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280697

RESUMO

The oxidative microenvironment in fibrotic livers often diminishes the effectiveness of mesenchymal stem cells (MSCs)-based therapy. Recent research suggests that pharmacological pre-treatment could enhance the therapeutic performance of MSCs. In this study, we assessed the impact of Arctium lappa L. polysaccharides (ALP) on the biological properties of nasal ectomesenchymal stem cells (EMSCs) and investigated the augmenting effect of ALP pretreatment on EMSCs (ALP-EMSCs) for the treatment of liver fibrosis. ALP treatment demonstrated multiple biological impacts on EMSC functions regarding liver fibrosis: firstly, it maintained the stemness of the cells while boosting the EMSCs' paracrine effects; secondly, it increased the expression of anti-inflammatory and antioxidant factors; thirdly, it inhibited the activation of hepatic stellate cells (HSCs) and liver collagen build-up by modulating the Wnt/ß-catenin signaling pathways. Collectively, these effects helped to halt the progression of liver fibrosis. Therefore, the use of ALP-EMSCs presents an innovative and promising approach for treating hepatic fibrosis in clinical scenarios.


Assuntos
Arctium , Células-Tronco Mesenquimais , Humanos , beta Catenina/metabolismo , Via de Sinalização Wnt , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo
2.
Br J Nutr ; 131(8): 1342-1351, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38149470

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a prevalent liver disorder, affecting approximately 25 % of the population. Coffee-drinking obese smokers exhibit lower body weights and decreased NAFLD rates, but the reasons behind this remain unclear. Additionally, the effect of nicotine, the main component of tobacco, on the development of NAFLD is still controversial. Our study aimed to explore the possible reasons that drinking coffee could alleviate NAFLD and gain weight and identify the real role of nicotine in NAFLD of obese smokers. A NAFLD model in mice was induced by administering nicotine and a high-fat diet (HFD). We recorded changes in body weight and daily food intake, measured the weights of the liver and visceral fat, and observed liver and adipose tissue histopathology. Lipid levels, liver function, liver malondialdehyde (MDA), superoxide dismutase (SOD), serum inflammatory cytokine levels and the expression of hepatic genes involved in lipid metabolism were determined. Our results demonstrated that nicotine exacerbated the development of NAFLD and caffeine had a hepatoprotective effect on NAFLD. The administration of caffeine could ameliorate nicotine-plus-HFD-induced NAFLD by reducing lipid accumulation, regulating hepatic lipid metabolism, alleviating oxidative stress, attenuating inflammatory response and restoring hepatic functions. These results might explain why obese smokers with high coffee consumption exhibit the lower incidence rate of NAFLD and tend to be leaner. It is essential to emphasise that the detrimental impact of smoking on health is multifaceted. Smoking cessation remains the sole practical and effective strategy for averting the tobacco-related complications and reducing the risk of mortality.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Humanos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/genética , Café , Cafeína , Nicotina/metabolismo , Nicotina/farmacologia , Dieta Hiperlipídica/efeitos adversos , Fumantes , Fígado/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Aumento de Peso , Metabolismo dos Lipídeos , Lipídeos/farmacologia , Camundongos Endogâmicos C57BL
3.
Nutrients ; 15(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38068804

RESUMO

The objective of this study was to investigate the preventive effects of polysaccharides extracted from the roots of Arctium lappa (ALP) against acute lung injury (ALI) models induced by lipopolysaccharide (LPS). The polysaccharides were extracted and characterized, and their anti-inflammatory and antioxidant capacities were assessed. The findings demonstrated that ALP could mitigate the infiltration of inflammatory cells and reduce alveolar collapse in LPS-induced ALI in mice. The expression levels of the pro-inflammatory factor TNF-α decreased, while the anti-inflammatory factor IL-10 increased. Furthermore, the administration of ALP improved the activities of lung antioxidant enzymes, including SOD, GSH, and CAT, and lowered MDA levels. These results suggest that ALP exhibits a preventive effect on ALI and has potential as an alternative treatment for lung injury.


Assuntos
Lesão Pulmonar Aguda , Arctium , Animais , Camundongos , Antioxidantes/metabolismo , Lipopolissacarídeos/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/prevenção & controle , Lesão Pulmonar Aguda/induzido quimicamente , Anti-Inflamatórios/uso terapêutico , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/metabolismo , Pulmão
4.
ACS Appl Mater Interfaces ; 15(48): 56014-56021, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37994881

RESUMO

Two-dimensional (2D) organic-inorganic hybrid perovskites (OIPs) have exhibited ideal prospects for perovskite photodetectors (PDs) owing to their remarkable environmental stability, tunable band gap, and structural diversity. However, most perovskites face the great challenge of a narrow spectral response. Integrating 2D OIPs with a suitable wide band gap semiconductor gives opportunities to broaden the response spectra. Here, a photodetector based on the BA2PbI4/GaN heterostructure with a broadband photoresponse covering from the ultraviolet (UV) to visible band is designed. We demonstrate that the device is capable of detecting in the UV region by p-GaN being integrated with BA2PbI4. The morphology and material optical properties of BA2PbI4 are characterized by transmission electron microscopy (TEM) and photoluminescence (PL). Additionally, the current-voltage (I-V) characteristics and photoresponses of the BA2PbI4/GaN heterojunction photodetector are investigated. The response spectrum of the photodetector is broadened from the visible to UV region, exhibiting good rectifying behavior in the dark conditions and a broadband photoresponse from the UV to the visible region. Additionally, the energy band is used to analyze the current mechanism of the BA2PbI4/GaN heterojunction PD. This study is expected to provide a new insight of optoelectronic devices by integrating 2D OIPs such as BA2PbI4 and wide-band-gap semiconductors such as GaN to broaden the response spectra.

5.
Nat Prod Res ; : 1-6, 2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37867310

RESUMO

In this study, water-soluble polysaccharides purified from burdock root were used to intervene in carbon tetrachloride (CCl4)-induced acute liver injury (ALI) of BRL3A hepatocytes and rats. Our results indicated that CCl4 significantly inhibited hepatocyte viability and upregulated the expression of reactive oxygen species (ROS), malondialdehyde (MDA), pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6), and the pro-apoptotic protein Bax. However, Arctium lappa L. root polysaccharides (ALP) could effectively ameliorate liver function and histopathology, oxidative stress, and inflammatory markers. In addition, ALP reduced the expression of apoptotic markers and promoted the proliferation of damaged hepatocytes. In conclusion, ALP possesses a hepatoprotective effect mediated by attenuating oxidative damage, inflammation and apoptosis in ALI.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37694794

RESUMO

BACKGROUND: Transplantation of stem cells/scaffold is an efficient approach for treating tissue injury including full-thickness skin defects. However, the application of stem cells is limited by preservation issues, ethical restriction, low viability, and immune rejection in vivo. The mesenchymal stem cell conditioned medium is abundant in bioactive functional factors, making it a viable alternative to living cells in regeneration medicine. METHODS: Nasal mucosa-derived ecto-mesenchymal stem cells (EMSCs) of rats were identified and grown in suspension sphere-forming 3D culture. The EMSCs-conditioned medium (EMSCs-CM) was collected, lyophilized, and analyzed for its bioactive components. Next, fibrinogen and chitosan were further mixed and cross-linked with the lyophilized powder to obtain functional skin patches. Their capacity to gradually release bioactive substances and biocompatibility with epidermal cells were assessed in vitro. Finally, a full-thickness skin defect model was established to evaluate the therapeutic efficacy of the skin patch. RESULTS: The EMSCs-CM contains abundant bioactive proteins including VEGF, KGF, EGF, bFGF, SHH, IL-10, and fibronectin. The bioactive functional composite skin patch containing EMSCs-CM lyophilized powder showed the network-like microstructure could continuously release the bioactive proteins, and possessed ideal biocompatibility with rat epidermal cells in vitro. Transplantation of the composite skin patch could expedite the healing of the full-thickness skin defect by promoting endogenous epidermal stem cell proliferation and skin appendage regeneration in rats. CONCLUSION: In summary, the bioactive functional composite skin patch containing EMSCs-CM lyophilized powder can effectively accelerate skin repair, which has promising application prospects in the treatment of skin defects.

7.
Biosensors (Basel) ; 13(8)2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37622917

RESUMO

Schistosomiasis, typically characterized by chronic infection in endemic regions, has the potential to affect liver tissue and pose a serious threat to human health. Detecting and screening for this disease early on is crucial for its prevention and control. However, existing methods encounter challenges such as low sensitivity, time-consuming processes, and complex sample handling. To address these challenges, we report a soluble egg antigen (SEA)-based functionalized gridless and meander-type AlGaN/GaN high electron mobility transistors (HEMT) sensor for the highly sensitive detection of antibodies to Schistosoma japonicum. Immobilization of the self-assembled membrane on the gate surface was verified using a semiconductor parameter analyzer, scanning electron microscope (SEM), and atomic force microscopy (AFM). The developed biosensor demonstrates remarkable performance in detecting anti-SEA, exhibiting a linear concentration range of 10 ng/mL to 100 µg/mL and a sensitivity of 0.058 mA/log (ng/mL). It also exhibits similar excellent performance in serum systems. With advantages such as rapid detection, high sensitivity, miniaturization, and label-free operation, this biosensor can fulfill the requirements for blood defense.


Assuntos
Schistosoma japonicum , Humanos , Animais , Anticorpos , Elétrons , Fígado , Microscopia de Força Atômica
8.
Nutrients ; 15(15)2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37571396

RESUMO

This innovative study investigates the effects of high-protein diets (milk protein) on the circadian rhythm of hepatic lipid metabolism. We aimed to understand how high-protein interventions regulate biological clock genes, maintain lipid metabolism balance, and affect the circadian rhythm of antioxidant levels in vivo. We divided 120 SPF-class C57BL/6J mice into the control, high-fat/low-protein (HF-LP), and high-fat/high-protein (HF-HP) groups. Mice were sacrificed during active (2 a.m. and 8 a.m.) and rest periods (2 p.m. and 8 p.m.). In the HF-LP group, hepatic lipid anabolic enzymes were consistently expressed at high levels, while key lipolytic enzymes slowly increased after feeding with no significant diurnal differences. This led to an abnormal elevation in blood lipid levels, a slow increase in and low levels of superoxide dismutase, and a rapid increase in malondialdehyde levels, deviating from the diurnal trend observed in the control group. However, high-protein interventions in the HF-HP group restored lipid synthase activity and the expression of key catabolic enzymes, exhibiting a precise circadian rhythm. It also improved the lipid-metabolism rhythm, which was disrupted by the high-fat diet. Overall, high-protein interventions restored the expression of key enzymes involved in lipid metabolism, improving the lipid-metabolism rhythm, which was disrupted by the high-fat diet.


Assuntos
Transtornos Cronobiológicos , Dieta Rica em Proteínas , Camundongos , Animais , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Dieta Hiperlipídica/efeitos adversos , Metabolismo dos Lipídeos , Ritmo Circadiano/fisiologia , Lipídeos
9.
Nanotechnology ; 34(31)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37137294

RESUMO

Carcinoembryonic antigen (CEA) is a well-known biomarker and validated serum biomarker for lung cancer. We introduce a simple label-free method for CEA detection. Specific recognition of CEA was made possible by immobilizing CEA antibodies in the sensing region of AlGaN/GaN high-electron-mobility transistors. The biosensors have a detection limit of 1 fg ml-1in phosphate buffer solution. This approach has advantages of integration, miniaturization, low cost, and rapid detection compared to other testing methods for lung cancer and could be used in future medical diagnostics.


Assuntos
Antígeno Carcinoembrionário , Gálio , Elétrons , Compostos de Alumínio
10.
Mol Nutr Food Res ; 67(12): e2200674, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36987812

RESUMO

SCOPE: Dityrosine (DT) is a protein oxidation marker present in many high-protein foods, such as dairy and meat products. Chronic dietary intake of DT induces oxidative stress damage in the liver and impairs energy metabolism. This study aims to investigate the mechanisms underlying the effects of DT on disrupted hepatic energy metabolism. METHODS AND RESULTS: The study investigates hepatic lipid accumulation, redox status imbalance, mitochondrial dysfunction, and energy metabolism disorders in 4-week-old C57BL/6J mice after 35 days of DT (420 µg kg-1 body weight) treatment. Transcriptome sequencing and quantitative real-time PCR in HepG2 cells show that DT mainly acted via miR-144-3p. miR-144-3p targets immune responsive gene 1 (IRG1) and decreases the fumaric acid level in the tricarboxylic acid (TCA) cycle, thereby decreasing nuclear factor erythroid 2-related factor 2 (Nrf2) expression and antioxidant activity. CONCLUSION: Administration of lycopene, a strong antioxidant, alleviates DT-induced damage in mice, confirming the involvement of the Nrf2 pathway in DT-induced abnormal hepatic lipid metabolism and energy homeostasis.


Assuntos
MicroRNAs , Fator 2 Relacionado a NF-E2 , Camundongos , Animais , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Regulação para Baixo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Lipídeos/farmacologia , Mitocôndrias
11.
Stem Cells Int ; 2023: 6890299, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655034

RESUMO

Background: Liver transplantation is limited by the insufficiency of liver organ donors when treating end-stage liver disease or acute liver failure (ALF). Ectodermal mesenchymal stem cells (EMSCs) derived from nasal mucosa have emerged as an alternative cell-based therapy. However, the role of EMSCs in acute liver failure remains unclear. Methods: EMSCs were obtained from the nasal mucosa tissue of rats. First, EMSCs were seeded on the gelatin-chitosan scaffolds, and the biocompatibility was evaluated. Next, the protective effects of EMSCs were investigated in carbon tetrachloride- (CCl4-) induced ALF rats. Finally, we applied an indirect coculture system to analyze the paracrine effects of EMSCs on damaged hepatocytes. A three-step nontransgenic technique was performed to transform EMSCs into hepatocyte-like cells (HLCs) in vitro. Results: EMSCs exhibited a similar phenotype to other mesenchymal stem cells along with self-renewal and multilineage differentiation capabilities. EMSC-seeded gelatin-chitosan scaffolds can increase survival rates and ameliorate liver function and pathology of ALF rat models. Moreover, transplanted EMSCs can secrete paracrine factors to promote hepatocyte regeneration, targeted migration, and transdifferentiate into HLCs in response to the liver's microenvironment, which will then repair or replace the damaged hepatocytes. Similar to mature hepatocytes, HLCs generated from EMSCs possess functions of expressing specific hepatic markers, storing glycogen, and producing urea. Conclusions: These results confirmed the feasibility of EMSCs in acute hepatic failure treatment. To our knowledge, this is the first time that EMSCs are used in the therapy of liver diseases. EMSCs are expected to be a novel and promising cell source in liver tissue engineering.

12.
Phys Chem Chem Phys ; 24(11): 6616-6626, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35234236

RESUMO

The high carrier mobility, appropriate band gap and good environmental stability of two-dimensional (2D) MoSi2N4 enable it to be an appropriate channel material for transistors with excellent performance. Therefore, we predict the performance of double-gate (DG) metal-oxide-semiconductor field-effect transistors (MOSFETs) based on monolayer (ML) MoSi2N4 by ab initio quantum-transport calculations. The results show that the on-state current of the p-type device is remarkable when the gate length is greater than 4 nm, which can meet the high performance requirements of the International Technology Roadmap for Semiconductors (ITRS), 2013 version. Moreover, the gate length can be reduced to 3 nm when an underlap (UL) structure is employed in the MOSFET, and the sub-threshold swing, intrinsic delay time and power consumption also perform well. The calculation results reveal that ML MoSi2N4 will be a promising alternative for transistor channel materials in the post-silicon era.

13.
Langmuir ; 38(2): 856-862, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34990133

RESUMO

Bacterial residue is one of the main causes of diseases and economic losses. In recent years, microfabrication technology has inspired the introduction of microstructures on the surfaces of relevant materials to provide antibacterial effects. This antibacterial method has become a popular research topic due to its safety, effectiveness, and stability. However, its exact mechanism is still under debate. In this study, normal force was introduced to bacteria on GaN nanopillars to investigate the mechanical sterilization effects and a computer simulation was conducted. The results show that the normal force induces highly efficient mechanical sterilization of the nanopillars, and their surfaces impede the attachment of bacteria. This study provides insights into the antibacterial effect of nanopillars and offers a potential antibacterial tool with high efficiency.


Assuntos
Antibacterianos , Bactérias , Antibacterianos/farmacologia , Simulação por Computador , Esterilização , Propriedades de Superfície
14.
Nanoscale Res Lett ; 16(1): 154, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34637014

RESUMO

At bio-safe concentrations, black phosphorus nanoparticles activated TG2, and promote the expression of ECM, which further promoted osteogenic differentiation of EMSCs. From these results, we can conclude that black phosphorus nanoparticles are suitable as biological factors in bone tissue engineering. Black phosphorus nanoparticles (BPs) present excellent biocompatibility and good biodegradability, which have been rigorously studied and proven. However, its utilization in bone tissue engineering fields is still in its infancy. Thus, the main purpose of the present study was to investigate the effects of BPs on osteogenic differentiation of ectodermal mesenchymal stem cell (EMSC) in vitro. Biocompatible BPs with high yield were prepared with a simple and efficient ultrasonication technique. EMSCs were isolated from adult rat nasal respiratory mucosa. Then, we treated EMSCs with BPs at different concentrations in vitro and examined the effect of BPs on osteogenic differentiation of EMSCs. In addition, inhibitor of transglutaminase 2 (TG2) and western blot were used to clarify the mechanism of the promoting effect of BPs on osteogenesis. Our results indicated that BPs could significantly enhance osteogenic differentiation of EMSCs in vitro. Nevertheless, BPs had no effect on EMSCs proliferation. Mechanistically, BPs promoted osteogenesis differentiation of EMSCs through upregulating TG2 expression. These results highlight the advantage of using chemical materials for novel engineering strategies of these highly promising small molecules for bone-tissue regeneration.

15.
Opt Express ; 29(4): 5466-5474, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726082

RESUMO

A metal electrode modification process for AlGaN-based metal-semiconductor-metal (MSM) photodetectors have been introduced to enhance the response of solar-blind ultraviolet (UV) light detection. The hexadecanethiol organic molecules are chemically adsorbed on the electrodes of high-Al-content Al0.6Ga0.4N MSM solar-blind UV photodetectors, which can reduce the work function of the metal electrode and change the height of the Schottky barrier. This modification process significantly increases the photocurrent and responsivity of the device compared with the referential photodetector without modification. Additionally, the adverse effects caused by the surface state and polarization of the AlGaN materials are effectively reduced, which can be beneficial for improving the electrical performances of III-nitride-based UV photodetectors.

16.
Amino Acids ; 53(1): 11-22, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33245424

RESUMO

As a promising cell therapy, neural crest-derived ectoderm mesenchymal stem cells (EMSCs) secrete high amounts of extracellular matrix (ECM) and neurotrophic factors, promoting neural stem cell (NSC) differentiation into neuronal lineages and aiding tissue regeneration. Additionally, the forced overexpression of secreted proteins can increase the therapeutic efficacy of the secretome. Tissue transglutaminase (TG2) is a ubiquitously expressed member of the transglutaminase family of calcium-dependent crosslinking enzymes, which can stabilize the ECM, inducing smart or living biomaterial to stimulate differentiation and enhance the neurogenesis of NSCs. In this study, we examined the neuronal differentiation of NSCs induced by TG2 gene-modified EMSCs (TG2-EMSCs) in a co-culture model directly. Two weeks after initiating differentiation, levels of the neuronal markers, tubulin beta 3 class III and growth-associated protein 43, were higher in NSCs in the TG2-EMSC co-culture group and those of the astrocytic marker glial fibrillary acidic protein were lower, compared with the control group. These results were confirmed by immunofluorescence, and laminin, fibronectin and sonic hedgehog (Shh) contributed to this effect. The results of western blot analysis and the enzyme-linked immunoassay showed that after TG2-EMSCs were co-cultured for 2 weeks, they expressed much higher levels of Shh than the control group. Moreover, the sustained release of Shh was observed in the TG2-EMSC co-culture group. Overall, our findings indicate that EMSCs can induce the differentiation of NSCs, of which TG2-EMSCs can promote the differentiation of NSCs compared with EMSCs.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Proteínas Hedgehog/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neurais/citologia , Transglutaminases/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Fibronectinas/metabolismo , Proteínas de Ligação ao GTP/genética , Laminina/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Neurais/metabolismo , Proteína 2 Glutamina gama-Glutamiltransferase , Ratos , Transglutaminases/genética
17.
Nanoscale Adv ; 3(9): 2649-2656, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-36134155

RESUMO

A nanostructure of In0.18Ga0.82N/GaN multiple quantum well (MQW) nanorods (NRs) was fabricated using top-down etching with self-organized nickel (Ni) nanoparticles as masks on the wafer. The optical properties of In0.18Ga0.82N/GaN MQW NRs were discussed by experiment and theory from a light absorption perspective. Three-dimensional (3D) optical images of NRs were successfully obtained by confocal laser scanning microscopy (CLSM) for physical observation of the optical phenomenon of InGaN/GaN MQW NRs. Moreover, optical simulations were performed by COMSOL Multiphysics via the three-dimensional finite-element method to explore the influences of NR geometrical parameters on optical absorption. The simulated results demonstrate that the absorption of NRs is higher than that of the film due to the waveguide properties of NRs resulting from their higher refractive index than embedding medium and higher aspect ratio than bulk. In addition, an increase in the diameter results in a red-shift of the absorption peak position of In0.18Ga0.82N/GaN MQW NRs. The smaller pitch enhances the near-field coupling of the nanorods and broadens the absorption peak. These results clearly illustrate the optical properties of In0.18Ga0.82N/GaN MQW NRs from the perspective of 3D confocal laser scanning microscopy. This work is promising for the applications of III-V optoelectronic devices.

18.
ACS Appl Mater Interfaces ; 11(8): 8453-8460, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30742412

RESUMO

Vertically oriented multilayered MoS2 nanosheets were successfully grown on p-GaN nanorod substrate using chemical vapor deposition (CVD) method. The p-GaN nanorod substrate was fabricated by dry etching employing self-assembled nickel (Ni) nanopartical as mask. Photoluminescence (PL) and Raman characterizations demonstrate the multilayered structure of MoS2 nanosheet growth on p-GaN nanorods as compared with the referential monolayer MoS2 on GaN wafer substrate under the same growth procedure. The growth model of vertical MoS2 nanosheet formed on GaN nanorods is evidently proposed according to the first-principle calculations. More importantly, it is demonstrated here that the as-grown vertical MoS2 nanosheets/p-GaN nanorod heterostructure holds promising applications in photodetector device, where high optical gain and broad spectral response in the visible range have been obtained.

19.
RSC Adv ; 8(58): 33193-33197, 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-35548113

RESUMO

Two-dimensional (2D) transition-metal dichalcogenides (TMDCs) on semiconductor substrates are important for next-generation electronics and optoelectronics. In this study, we demonstrate the growth of monolayer MoS2 on a lattice-matched gallium nitride (GaN) semiconductor substrate by chemical vapor deposition (CVD). The monolayer MoS2 triangles exhibit optical properties similar to that of typical single-crystal MoS2 sheets, as verified by the Raman, photoluminescence, and morphological characterizations. The Raman and PL features and their intensity mappings suggest that the as-grown MoS2 on GaN substrate can achieve high quality and uniformity, demonstrating that GaN substrate is favorable for 2D MoS2 growth. Moreover, the interfacial property and stacking structure were investigated by first-principles density functional theory (DFT) calculations to confirm the interlayer interactions of monolayer MoS2 on GaN. Accordingly, the ability to grow high quality monolayer MoS2 on semiconductor GaN substrate would open a new route toward the synthesis of hetero and composite structures for promising electronic and optoelectronic device applications.

20.
Food Chem ; 197(Pt A): 891-9, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26617031

RESUMO

This study investigated the effects of dephosphorylation extent on infant in vitro gastric clotting property and gastrointestinal digestibility of milk protein concentrate. Dephosphorylation was affected by phosphatase type and incubation pH. A series of milk protein concentrate with 0-69% dephosphorylation were obtained by incubation with calf intestinal alkaline phosphatase at pH 6.5 for 0-420 min. Both ß- and αs1-caseins in the modified milk protein concentrate showed multiply dephosphorylated isoforms with different numbers of phosphate groups depending on the extent of dephosphorylation. With increased dephosphorylation of milk protein concentrate, the gastric clotting extent decreased and the gastrointestinal digestibility increased under infant in vitro conditions. These results suggested the potential of developing a dephosphorylated milk protein concentrate, with improved gastric clotting property and gastrointestinal digestibility, to simulate the multiply phosphorylated patterns of human casein and hence to further the humanization of infant formula on a molecular level.


Assuntos
Fosfatase Alcalina/química , Fórmulas Infantis/química , Proteínas do Leite/química , Modelos Biológicos , Fosfatos/análise , Proteólise , Animais , Fenômenos Bioquímicos , Caseínas/química , Bovinos , Suco Gástrico/química , Humanos , Lactente
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