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1.
Chem Rev ; 124(4): 1992-2079, 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38335114

ABSTRACT

Twisted van der Waals (vdW) quantum materials have emerged as a rapidly developing field of two-dimensional (2D) semiconductors. These materials establish a new central research area and provide a promising platform for studying quantum phenomena and investigating the engineering of novel optoelectronic properties such as single photon emission, nonlinear optical response, magnon physics, and topological superconductivity. These captivating electronic and optical properties result from, and can be tailored by, the interlayer coupling using moiré patterns formed by vertically stacking atomic layers with controlled angle misorientation or lattice mismatch. Their outstanding properties and the high degree of tunability position them as compelling building blocks for both compact quantum-enabled devices and classical optoelectronics. This paper offers a comprehensive review of recent advancements in the understanding and manipulation of twisted van der Waals structures and presents a survey of the state-of-the-art research on moiré superlattices, encompassing interdisciplinary interests. It delves into fundamental theories, synthesis and fabrication, and visualization techniques, and the wide range of novel physical phenomena exhibited by these structures, with a focus on their potential for practical device integration in applications ranging from quantum information to biosensors, and including classical optoelectronics such as modulators, light emitting diodes, lasers, and photodetectors. It highlights the unique ability of moiré superlattices to connect multiple disciplines, covering chemistry, electronics, optics, photonics, magnetism, topological and quantum physics. This comprehensive review provides a valuable resource for researchers interested in moiré superlattices, shedding light on their fundamental characteristics and their potential for transformative applications in various fields.

3.
Nanoscale ; 15(48): 19533-19545, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-37937449

ABSTRACT

Excitonic complexes, bound states of electrons and holes, provide a promising platform in monolayer transition-metal dichalcogenide (TMDC) semiconductors for investigating diverse many-body interaction phenomena. The surrounding dielectric environment has been found to strongly influence the excitonic properties of the TMDC monolayers. While the impact of different dielectric surroundings on two-dimensional semiconductor materials and their strong correlations have been well studied, the effects on exciton formation and its properties resulting from a further reduction in dielectric screening remain elusive. In this study, we examined free-standing tungsten disulfide (WS2) monolayers, where the efficient generation of higher-order correlated excitonic complexes is readily observed. This phenomenon arises from the effective mutual interactions among excitons and internal carriers, attributed to the modulated exciton dynamics generated by the further reduced dielectric screening effect in the freestanding structure. The formation efficiency of excitonic complexes is enhanced and the multiple biexciton species (five particles such as charged biexcitons and acceptor/donor-bound biexcitons) are successfully induced under low excitation intensity and moderate temperature conditions. Our findings offer valuable insights into the influence of the dielectric environment on exciton interactions and enable a productive avenue for exploring fundamental many-body interactions, providing new possibilities for dielectric engineering of atomic thin semiconductors.

4.
Sci Total Environ ; 903: 166159, 2023 Dec 10.
Article in English | MEDLINE | ID: mdl-37572910

ABSTRACT

Controlling ammonia nitrogen is very important in intensive aquaculture. This study evaluated how different management strategies, i.e., chemoautotrophic (control), heterotrophic bacterial enhancement using carbon in glucose or polyhydroxy butyrate-hydroxy valerate (PHBV), and mature biofloc application, affect water quality and microbial community structure and composition. The management strategies were examined during the domestication and fish culture stages. In the domestication stage, the average NO2--N concentration, pH, and DO in the glucose-added groups were significantly lower than those in the control and PHBV groups. All water quality parameters differed significantly among treatment groups in the culture stage. Carbon additions decreased both bacterial richness and diversity in the fish culture stage. Both principal coordinate analysis and hierarchical cluster analysis grouped the 33 bacteria community samples from the two stages into four clusters, which were closely related to management strategy. The dominant taxa of the clusters were identified using linear discriminant analysis effect size (LEfSe). The biomarkers of Cluster I included Marinomonas, Photobacterium, and Vibrio. Porticoccus and Clade-1a were identified as the biomarkers of Cluster II. Marivia, Leucothrix, and Phaeodactylibacter were identified as the biomarkers of Cluster IV. The Cluster I biomarkers were positively correlated with NO2--N, while those of Cluster IV were positively correlated with NO3--N. The redundancy analysis showed that the bacterial communities and biomarkers were influenced by water quality parameters. Quantitative real-time PCR analysis revealed significant differences in the abundances of the amoA and nxrB genes among treatments and between the two stages. The abundance of the amoA gene was higher in the control group than in the carton-added treatments at the ends of both stages. This study provides an important theoretical basis for the selection of efficient ammonia nitrogen control strategies in aquaculture systems.

5.
ACS Nano ; 16(12): 21505-21517, 2022 Dec 27.
Article in English | MEDLINE | ID: mdl-36441581

ABSTRACT

Twisted van der Waals heterostructures are known to induce surprisingly diverse and intriguing phenomena, such as correlated electronic phase and unconventional optical properties. This can be realized by controlled rotation of adjacent atomic planes, which provides an uncommon way to manipulate inelastic light-matter interactions. Here, we discover an extraordinary blue shift of 5-6 wavenumbers for high-frequency phonon modes in WS2/WSe2 twisted heterobilayers, captured meticulously using Raman spectroscopy. Phonon spectra displace rapidly over a subtle change in interlayer twist angle owing to heterostrain and atomic reconstruction from the Moiré pattern. First-order linear coefficients of the phonon modes in twisted heterostructures are further found to increase largely compared to their monolayer counterpart and vary immensely with the twist angle. Exceptional and extravagant enhancement of up to 50-fold is observed in the Raman vibrational intensity at a specific twist angle; this is largely influenced by the resonance process derived from a simple critical twist angle model. In addition, we depict how the resonance can be modulated by changing the thermal conditions and also the stacking angle. Therefore, our work further highlights the twist-driven phonon dynamics in pristine two-dimensional heterostructures, adding vital insight into Moiré physics and promoting comprehensive understanding of structural and optical properties in Moiré superlattices.

6.
Nature ; 610(7932): 478-484, 2022 10.
Article in English | MEDLINE | ID: mdl-36224395

ABSTRACT

Strong, long-range dipole-dipole interactions between interlayer excitons (IXs) can lead to new multiparticle correlation regimes1,2, which drive the system into distinct quantum and classical phases2-5, including dipolar liquids, crystals and superfluids. Both repulsive and attractive dipole-dipole interactions have been theoretically predicted between IXs in a semiconductor bilayer2,6-8, but only repulsive interactions have been reported experimentally so far3,9-16. This study investigated free-standing, twisted (51°, 53°, 45°) tungsten diselenide/tungsten disulfide (WSe2/WS2) heterobilayers, in which we observed a transition in the nature of dipolar interactions among IXs, from repulsive to attractive. This was caused by quantum-exchange-correlation effects, leading to the appearance of a robust interlayer biexciton phase (formed by two IXs), which has been theoretically predicted6-8 but never observed before in experiments. The reduced dielectric screening in a free-standing heterobilayer not only resulted in a much higher formation efficiency of IXs, but also led to strongly enhanced dipole-dipole interactions, which enabled us to observe the many-body correlations of pristine IXs at the two-dimensional quantum limit. In addition, we firstly observed several emission peaks from moiré-trapped IXs at room temperature in a well-aligned, free-standing WSe2/WS2 heterobilayer. Our findings open avenues for exploring new quantum phases with potential for applications in non-linear optics.

7.
ACS Appl Mater Interfaces ; 14(36): 41165-41177, 2022 Sep 14.
Article in English | MEDLINE | ID: mdl-36048513

ABSTRACT

The study of transport and diffusion dynamics of quasi-particles such as excitons, trions, and biexcitons in two-dimensional (2D) semiconductors has opened avenues for their application in high-speed excitonic and optoelectronic devices. However, long-range transport and fast diffusion of these quasi-particles have not been reported for 2D systems such as transition metal dichalcogenides (TMDCs). The reported diffusion coefficients from TMDCs are low, limiting their use in high-speed excitonic devices and other optoelectronic applications. Here, we report the highest exciton diffusion coefficient value in monolayer WS2 achieved via engineering the radiative lifetime and diffusion lengths using static back-gate voltage and substrate engineering. Electrostatic doping is observed to modulate the radiative lifetime and in turn the diffusion coefficient of excitons by ∼three times at room temperature. By combining electrostatic doping and substrate engineering, we push the diffusion coefficient to an extremely high value of 86.5 cm2/s, which has not been reported before in TMDCs and is even higher than the values in some 1D systems. At low temperatures, we further report the control of dynamic and spatial diffusion of excitons, trions, and biexcitons from WS2. The electrostatic control of dynamics and transport of these quasi-particles in monolayers establishes monolayer TMDCs as ideal candidates for high-speed excitonic circuits, optoelectronic, and photonic device applications.

8.
Nanoscale ; 14(23): 8260-8270, 2022 Jun 16.
Article in English | MEDLINE | ID: mdl-35660824

ABSTRACT

Monolayer transition metal dichalcogenides (mTMDs) possess a direct band gap and strong PL emission that is highly sensitive to doping level and interfaces, laying the foundation for investigating the contact between mTMD and metal via PL spectroscopy. Currently, electrical methods have been utilized to measure the contact resistance (RC), but they are complicated, time-consuming, high-cost and suffer from inevitable chemical disorders and Fermi level pinning. In addition, previously reported contact resistances comprise both Schottky barrier and tunnel barrier components. Here, we report a simple, rapid and low-cost method to study the tunnel barrier dominated contact resistance of mTMD based junctions through PL spectroscopy. These junctions are free from chemical disorders and Fermi level pinning. Excluding the Schottky barrier component, solely tunnel barrier dominated contact resistances of 1 L MoSe2/Au and 1 L MoSe2/graphene junctions were estimated to be 147.8 Ω µm and 54.9 Ω µm, respectively. Density functional theory (DFT) simulations revealed that the larger RC of the former was possibly due to the existence of intrinsic effective potential difference (Φbarrier) between mTMD and metal. Both junctions exhibit an increasing tendency of RC as temperature decreases, which is probably attributed to the thermal expansion coefficient (TEC) mismatch-triggered interlayer spacing (d) increase and temperature-induced doping. Remarkably, a significant change of RC was observed in 1 L MoSe2/Au junctions, which is possibly ascribed to the changes of their orbital overlaps. Our results open new avenues for exploring fundamental metal-semiconductor contact principles and constructing high-performance devices.

9.
Ecotoxicol Environ Saf ; 237: 113535, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35461028

ABSTRACT

Foodborne mycotoxins are toxic metabolites that are produced by fungi. The widespread contamination of food and its by-products by mycotoxins is a global food safety problem that potentially threatens public health and other exposed animals. Most foodborne mycotoxins induce hepatotoxicity. However, only few studies have investigated the regulatory mechanisms of mitochondrial calcium transport monomers in mycotoxin-induced hepatotoxicity. Therefore, according to relevant studies and reports, this review suggests that intracellular Ca(2 +) homeostasis and mitochondrial Ca(2 +) uniporter are involved in the regulation of mycotoxin-induced hepatotoxicity. This review provides some ideas for future research involving mitochondrial Ca(2 +) uniporter in the molecular targets of mycotoxin-induced hepatotoxicity, as well as a reference for the research and development of related drugs and the treatment of related diseases.


Subject(s)
Chemical and Drug Induced Liver Injury , Mycotoxins , Animals , Calcium , Calcium Channels , Chemical and Drug Induced Liver Injury/etiology , Food Contamination/analysis , Mycotoxins/toxicity
10.
Gen Physiol Biophys ; 41(2): 151-158, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35416178

ABSTRACT

Lupus nephritis (LN) occurs with inflammatory lesion in patients suffering from systemic lupus erythematosus (SLE). Tumor necrosis factor (TNF) receptor associated factor 3 (TRAF3) is an important mediator in inflammation. To explore the roles of TRAF3 in LN, the LN mouse model was firstly established with intraperitoneal (i.p.) injection of pristine. Our results found that the amount of urinary protein was increased evidently at day 28, and renal damage occurred in the LN mouse model, but the TRAF3 knockdown reduced the urinary protein and alleviated the inflammatory lesion. The proinflammatory cytokines TNF-α, IL-1ß, IL-17a, IFN-γ and IgM, IgG antibody were enriched, but there was little amount of IL-10 in the LN mouse model. Moreover, the amount of CD40+ B cells, CD4+ T cells sub-type, Th17 cells were abundant, and the proteins TRAF3, TRAF2, NF-κBp52, IKKα, ICAM1 in the kidney were highly expressed in the LN mouse model. However, TRAF3 knockdown enhanced the production of IL-10 and reduced the amount of pro-inflammatory cytokines, immunoglobulin, and the protein expressions of TRAF3, TRAF2, NF-κBp52, IKKα, ICAM1. In conclusion, TRAF3 plays a role in LN by regulating Th17 cell and Treg cell balance as well as NF-κB signaling pathway in mice.


Subject(s)
Lupus Nephritis , NF-kappa B , Animals , Cytokines/metabolism , I-kappa B Kinase/metabolism , Interleukin-10/metabolism , Lupus Nephritis/metabolism , Lupus Nephritis/pathology , Mice , NF-kappa B/metabolism , Signal Transduction , T-Lymphocytes, Regulatory , TNF Receptor-Associated Factor 2/metabolism , TNF Receptor-Associated Factor 3/metabolism , Th17 Cells
11.
Nutr J ; 20(1): 83, 2021 10 03.
Article in English | MEDLINE | ID: mdl-34602079

ABSTRACT

BACKGROUND: A growing number of researches supported that dietary fructose was associated with most of the key features of metabolic syndrome (MetS). However, there was no related epidemiological studies among Chinese population, despite the sharp increase in MetS cases. This study explores the relationship between dietary fructose and MetS among Chinese residents aged 45 and above. METHODS: A total of 25,528 participants (11,574 males and 13,954 females) were included in this nationwide representative cross-sectional study of China National Nutrition and Health Survey. Dietary fructose intake was assessed by 3-day 24-h dietary records. MetS was defined by the International Diabetes Federation and Chinese Diabetes Society criteria. RESULTS: The consumption of dietary fructose was 11.6 g/day for urban residents and 7.6 g/day for rural residents. Fruits and vegetables as well as their products were the main sources of fructose intake. There was no association between dietary fructose intake and the odds of having MetS in both urban (P = 0.315) and rural residents (P = 0.230) after adjustment for confounding factors. Moreover, for urban residents participating physical activities, the odds of having MetS in the fourth quartiles (OR: 0.67; 95%CI: 0.52-0.87) was lower than that in the first quartile. In the sensitivity analysis, a significant reduction in the odds of having MetS was also found in the fourth quartiles (OR, 95%CI: 0.68, 0.51-0.90; 0.67, 0.49-0.91; 0.74, 0.56-0.99) compared with the first quartile when excluding smokers, alcohol users, and underweight/obesity, respectively. And there was no association between dietary fructose intake and the odds of having MetS after multivariate adjustment stratified by gender, smoking and alcohol use. CONCLUSIONS: Under the current dietary fructose intake status, there was no association between dietary fructose intake and the odds of having MetS among Chinese residents aged 45 and above. Physical activity and relatively low fructose intake may have a beneficial synergistic effect on MetS.


Subject(s)
Metabolic Syndrome , China/epidemiology , Cross-Sectional Studies , Female , Fructose , Health Surveys , Humans , Male , Metabolic Syndrome/epidemiology , Risk Factors
12.
Appl Opt ; 59(8): 2298-2307, 2020 Mar 10.
Article in English | MEDLINE | ID: mdl-32225761

ABSTRACT

Herein we propose a polarimetric imaging system that uses a microgrid polarizer placed on the conjugate point of two telecentric optical paths, matching large polarizers with small sensors and thus effectively decreasing optical crosstalk and increasing imaging accuracy. We define a new parameter used to construct the high-precision polarization vector transfer model under crosstalk. Using the equivalent surface of the detector, we establish the relationship between focal shift and crosstalk ratio and obtain a multi-physical coupling mathematical model that accounts for the crosstalk ratio, extinction ratio, sensor error, target vector, and imaging accuracy of the system. The relayed-microgrid polarimetric imaging system is anticipated to be able to help identify objects of interest for remote sensing and military applications.

14.
Int Immunopharmacol ; 74: 105634, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31254959

ABSTRACT

OBJECTIVE: Heme oxygenase-1 (HO-1) plays a critical protective role in various insults-induced acute lung injury (ALI) through its strong anti-inflammatory, anti-oxidant, and anti-apoptotic properties, but its protective role and mechanism on seawater aspiration-induced acute lung injury remains unclear. This study aimed to explore the therapeutic potential and mechanism of HO-1 to attenuate seawater aspiration-induced ALI in vivo and in vitro. METHODS: The viability and invasion of A549 cell were analyzed through cell counting kit-8 and lactate dehydrogenase release assay; the transcriptional level of inflammatory cytokines (TNF-α, IL-6, IL-8 and MCP-1) and cell proliferation-related cytokines (FoxM1, Ccnb1 and Cdc25C) in seawater-treated A549 cell were tested by qPCR; apoptotic cells were analyzed by flow cytometryd; HO-1mRNA and protein were determined by qPCR and western blotting; the fluorescent indicators (DCFH-DA, dihydroethidium, MitoSox Red and Fluo-4) were used to monitor generation of ROS and mitochondrial function. The lung wet/dry weight radio and lactate dehydrogenase activity, Sirius red staining, TUNEL assay and immunohistochemical staining with anti-pan Cytokeratin antibody were analyzed in seawater-drowning mice. The role of HO-1 on seawater-drowning pulmonary injury was explored via HO-1 activity inhibitors (Zinc protoporphyrin) in vitro and in vivo. RESULTS: Seawater exposure decreased the cellular viability, increased the production of pro-inflammatory cytokines (IL-6, IL-8 and TNF-α), induced cellular apoptosis and inhibited the expression of cell proliferation-related cytokines (FoxM1, Ccnb1 and Cdc25C). Moreover, seawater exposure led to mitochondrial dysfunction in A549 cells. Supplement of HO-1 sepcific inducer (heme) or its catalytic product (biliverdin) significantly attenuated seawater-induced A549 damage and promoted cell proliferation. However, Zinc protoporphyrin abolished the beneficial effects of HO-1 on seawater drowning-induced pulmonary tissue injury. CONCLUSION: HO-1 attenuates seawater drowning-induced lung injury by its anti-inflammatory, anti-oxidative, and anti-apoptosis function.


Subject(s)
Acute Lung Injury/metabolism , Drowning/metabolism , Heme Oxygenase-1/metabolism , A549 Cells , Animals , Biliverdine/metabolism , Cell Proliferation , Cytokines/genetics , Humans , Inflammation/metabolism , Male , Mice, Inbred BALB C , Oxidative Stress , Seawater
15.
ACS Nano ; 13(5): 5335-5343, 2019 May 28.
Article in English | MEDLINE | ID: mdl-31017755

ABSTRACT

In this work, we show how domain-engineered lithium niobate can be used to selectively dope monolayer molybdenum selenide (MoSe2) and tungsten selenide (WSe2) and demonstrate that these ferroelectric domains can significantly enhance or inhibit photoluminescence (PL), with the most dramatic modulation occurring at the heterojunction interface between two domains. A micro-PL and Raman system is used to obtain spatially resolved images of the differently doped transition metal dichalcogenides (TMDs). The domain-inverted lithium niobate causes changes in the TMDs due to electrostatic doping as a result of the remnant polarization from the substrate. Moreover, the differently doped TMDs (n-type MoSe2 and p-type WSe2) exhibit opposite PL modulation. Distinct oppositely charged domains were obtained with a 9-fold PL enhancement for the same single MoSe2 sheet when adhered to the positive (P+) and negative (P-) domains. This sharp PL modulation on the ferroelectric domain results from different free electron or hole concentrations in the material's conduction band or valence band. Moreover, excitons dissociate rapidly at the interface between the P+ and P- domains due to the built-in electric field. We are able to adjust the charge on the P+ and P- domains using temperature via the pyroelectric effect and observe rapid PL quenching over a narrow temperature range, illustrating the observed PL modulation is electronic in nature. This observation creates an opportunity to harness the direct bandgap TMD 2D materials as an active optical component for the lithium niobate platform using domain engineering of the lithium niobate substrate to create optically active heterostructures that could be used for photodetectors or even electrically driven optical sources on-chip.

16.
Medicine (Baltimore) ; 98(8): e14619, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30813192

ABSTRACT

BACKGROUND: Previous clinical studies reported low molecular weight heparin (LMWH) monotherpay has been utilized for the treatment of recurrent abortion (RCA) with antiphospholipid system (APS). However, its efficacy is still inconclusive. This systematic review aims to assess its efficacy and safety for patients with RCA and APS. METHODS: A systematic literature search for article up to February 2019 will be conducted in 9 databases: Cochrane Library, EMBASE, MEDILINE, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Information, and Wanfang Data. Inclusion criteria are randomized control trials of LMWH monotherpay for patients with RCA and APS. The Cochrane risk of bias tool will be used to evaluate the methodological quality for each qualified study. The summary results will be showed by using fixed-effects and random-effects models for pooling the data based on the heterogeneity of included studies. RESULTS: This systematic review will assess the clinical efficacy and safety of LMWH monotherpay in treating RCA with APS. The primary outcome is pregnancy loss. The secondary outcomes include frequency of preterm delivery, live birth rates, maternal and fetal complications, as well as adverse events. CONCLUSION: The findings of this study will summarize the present evidence to judge whether LMWH monotherpay is an effective therapy for patients with RCA and APS. DISSEMINATION AND ETHICS: The findings of this study will be published by through peer-reviewed journals. This study does not needs ethic documents, because it will not analyze individual patient data. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019121064.


Subject(s)
Abortion, Habitual/drug therapy , Anticoagulants/therapeutic use , Antiphospholipid Syndrome/drug therapy , Heparin, Low-Molecular-Weight/therapeutic use , Abortion, Habitual/etiology , Anticoagulants/adverse effects , Antiphospholipid Syndrome/complications , Female , Heparin, Low-Molecular-Weight/adverse effects , Humans , Pregnancy , Pregnancy Outcome/epidemiology , Research Design , Treatment Outcome
17.
Nanoscale ; 11(2): 418-425, 2019 Jan 03.
Article in English | MEDLINE | ID: mdl-30543239

ABSTRACT

The performance of optoelectronic devices based on monolayer transition-metal dichalcogenide (mTMD) semiconductors is significantly affected by the contact at the mTMD-metal interface, which is dependent on interlayer interactions and coupling. Here, we report a systematic optical method to investigate the interlayer charge transfer and coupling in a mTMD-metal heterojunction. Giant photoluminescence (PL) quenching was observed in a monolayer MoS2/Pd (1L MoS2/Pd) junction which is mainly due to the efficient interlayer charge transfer between Pd and MoS2. 1L MoS2/Pd also exhibits an increase in the PL quenching factor (η) as the temperature decreases, due to a reduction of the interlayer spacing. Annealing experiments were also performed which supported interlayer charge transfer as the main mechanism for the increase of η. Moreover, a monolayer MoS2/Au (1L MoS2/Au) junction was fabricated for engineering the interlayer charge transfer. Interestingly, a narrowing effect of the full width at half maximum (FWHM) was encountered as the junctions changed from 1L MoS2/SiO2 → 1L MoS2/Au → 1L MoS2/Pd, possibly originating from a change of the doping level induced weakening of exciton-carrier scattering. Our results deepen the understanding of metal-semiconductor junctions for further exploring fundamental phenomena and enabling high-performance devices using mTMD-metal junctions.

18.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(5): 468-472, 2019 Sep.
Article in Chinese | MEDLINE | ID: mdl-31894682

ABSTRACT

OBJECTIVE: To investigate the protective effects of curcumin on bile duct ligation(BDL)-induced liver cholestasis in mice, so as to provide a new treatment strategy for liver fibrosis. METHODS: Forty-two healthy adult male BALB/c mice were randomly divided into sham group (n =6), sham+curcumin group (n=6), BDL treatment group (n=10), BDL+curcumin group(n=10), BDL+curcumin+ZnPP group (n=10). Seven days after BDL operation, the sham operation + curcumin group and the BDL+ curcumin group were treated with curcumin at the dose of 30 mg/kg by intraperitoneal injection once a day for 7 days.The mice in BDL+ curcumin +ZnPP group were treated with curcumin (30 mg/kg) and ZnPP (50 µmol/kg) by intraperitoneal injection once a day for 7 days. For the sham group and the BDL group, mice were treated with equal-volume saline daily by intraperitoneal injection. After 14 days of BDL, the plasma and liver tissues were collected, the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. The pathological changes of liver tissue and liver fibrosis were observed, and the protein expression of HO-1 in liver tissue was detected. RESULTS: Compared with the sham group, mice in the BDL group had enlarged liver gallbladder and the serum levels of ALT and AST were increased significantly (P<0.05). Meanwhile, the results of Sirius red staining and qRT-PCR of pro-fibrosis related genes showed collagen deposition in the liver, and immunohistochemistry of macrophages and neutrophils showed inflammatory cell infiltration in the liver. Compared with the BDL group, the serum levels of ALT and AST in the curcumin treatment group were decreased significantly (P<0.05), collagen deposition and inflammatory cell infiltration were improved, and HO-1 expression was increased (P<0.05) after curcumin treatement. In the curcumin treatment group, the protective effect of curcumin on liver injury could be reversed by HO-1 active inhibitor ZnPP. CONCLUSION: Curcumin can improve liver inflammation and fibrosis caused by BDL, and this protective effect is related to the regulation of HO-1 activity by curcumin.


Subject(s)
Cholestasis , Curcumin , Liver Cirrhosis , Animals , Curcumin/pharmacology , Curcumin/therapeutic use , Liver/drug effects , Liver Cirrhosis/drug therapy , Liver Cirrhosis/prevention & control , Male , Mice , Mice, Inbred BALB C , Treatment Outcome
19.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 30(9): 855-860, 2018 Sep.
Article in Chinese | MEDLINE | ID: mdl-30309411

ABSTRACT

OBJECTIVE: To investigate the effect of caveolin-1 scaffolding domain (CSD) peptides on heme oxygenase-1 (HO-1) activity increasing and M1/M2 phenotype polarization in rat alveolar macrophages (AMs) induced by lipopolysaccharide (LPS). METHODS: Bioinformatics was used to analyze the binding of full-length wild-type CSD polypeptide and 101 amino acid deleted truncated mutant CSD polypeptide (Δ101CSD) to HO-1. Primary AMs were isolated from rats, when cell fusion reached 80%, they were synchronized with serum-free medium and divided into five groups: no treatment was given to the blank control group; LPS group was treated with 100 µg/L LPS for 16 hours; LPS + hemin group was treated with 100 µg/L LPS and 20 µmol/L hemin for 16 hours; wild-type CSD polypeptide + LPS + hemin group was pretreated with 10 µmol/L wild-type CSD polypeptide 6 hours before LPS treatment; Δ101CSD + LPS + hemin group was pretreated with 10 µmol/L Δ101CSD polypeptide 6 hours before LPS treatment. After treatment for 16 hours, the co-localization between caveolin-1 (Cav-1) and HO-1 was displayed by confocal microscope; the mRNA expressions of inflammatory cytokines interleukin-1ß (IL-1ß) and monocyte chemoattractant protein-1 (MCP-1) and M1/M2 polarization cytokines tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), leukocyte differentiation antigen 206 (CD206) and IL-10 were determined by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-qPCR); the HO-1 activity and nitric oxide (NO) production were determined by spectrophotometry. RESULTS: Bioinformatics analysis showed: both wild-type CSD and Δ101CSD peptides could bind to HO-1, and there was no significant difference in the binding ability between the two peptides, but the deletion of 101 Arg resulted in the disappearance of part of the binding region between Δ101CSD and HO-1. The results of laser confocal microscopy showed: the expressions of Cav-1 and HO-1 were lowed in the blank control group, and Cav-1 was bound to HO-1 in LPS group and LPS + hemin group. Both wild-type CSD and Δ101CSD peptides pretreatment could significantly reduce the binding of HO-1 to Cav-1 induced by LPS. HO-1 activity analysis showed: after LPS stimulation, the activity of HO-1 was significantly higher than that of the blank control group; the activity of HO-1 induced by LPS was increased by hemin; after pretreatment with two kinds of CSD peptides, the activity of HO-1 was further increased, and the effect of wild-type CSD peptide was more significant, which showed a statistically significant difference as compared with that of LPS + hemin group (pmol×mg-1×h-1: 3 683±266 vs. 2 408±132, P < 0.05). RT-qPCR results showed: LPS could induce elevation of cytokines and M1 markers and decrease of M2 markers, while hemin could inhibit LPS-induced inflammatory response and M1/M2 phenotypic polarization. Compared with LPS + hemin group, after pretreatment with wild-type CSD peptide, the levels of inflammatory factors in AMs were decreased, and the mRNA expression levels of TNF-α and iNOS, M1 markers, were decreased [TNF-α mRNA (2-ΔΔCt): 6.82±0.05 vs. 8.70±0.24, iNOS mRNA (2-ΔΔCt): 331.50±32.05 vs. 506.70±0.10, both P < 0.05], and IL-10 mRNA expression level was increased (2-ΔΔCt: 269.09±6.54 vs. 119.05±3.30, P < 0.05). The deletion of 101 site partially weakened the inhibitory effect of CSD peptides on inflammatory factors and only reduced the expression of iNOS mRNA (2-ΔΔCt: 429.11±8.92 vs. 506.70±0.10, P < 0.05), indicating that its ability to transform AMs from M1 phenotype to M2 phenotype was poor. The two peptides had no effect on the expression of CD206. CONCLUSIONS: Wild-type CSD had beneficial effects of anti-inflammation by reducing Cav-1 binding to HO-1 induced by LPS, restoring the HO-1 activity and driving M2 phenotype in alveolar macrophages.


Subject(s)
Caveolin 1/metabolism , Cell Polarity , Heme Oxygenase-1/metabolism , Macrophages, Alveolar , Peptide Fragments/metabolism , Animals , Lipopolysaccharides/metabolism , Phenotype , Rats
20.
Appl Opt ; 57(25): 7344-7351, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-30182954

ABSTRACT

High-sensor SNR and high extinction ratio (ER), which are often contradictory requirements for nanowire-filter-based polarimetric imaging systems, aid in attenuating polarimetric imaging system errors. Expressions were derived to analyze their attenuation effects and then simplified using photoelectronic numbers received by superpixels (PNRS). The first-derivative ratios of PNRS and ER were calculated to compare their attenuation effects. Mathematical models and experiments conducted using polarimetric imaging systems with various ERs and PNRSs indicate that systems with low PNRS and high ER exhibit a polarization error affected more by the attenuation effect of the PNRS than that of the ER. When the system ER is higher than 28, the attenuation effect of the PNRS is higher than that of the ER. Thus, system error attenuation is a trade-off between sensor SNR and ER.

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