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1.
Plant Cell ; 35(9): 3522-3543, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37352123

ABSTRACT

Uridine diphosphate (UDP)-sugars are important metabolites involved in the biosynthesis of polysaccharides and may be important signaling molecules. UDP-glucose 4-epimerase (UGE) catalyzes the interconversion between UDP-Glc and UDP-Gal, whose biological function in rice (Oryza sativa) fertility is poorly understood. Here, we identify and characterize the botryoid pollen 1 (bp1) mutant and show that BP1 encodes a UGE that regulates UDP-sugar homeostasis, thereby controlling the development of rice anthers. The loss of BP1 function led to massive accumulation of UDP-Glc and imbalance of other UDP-sugars. We determined that the higher levels of UDP-Glc and its derivatives in bp1 may induce the expression of NADPH oxidase genes, resulting in a premature accumulation of reactive oxygen species (ROS), thereby advancing programmed cell death (PCD) of anther walls but delaying the end of tapetal degradation. The accumulation of UDP-Glc as metabolites resulted in an abnormal degradation of callose, producing an adhesive microspore. Furthermore, the UDP-sugar metabolism pathway is not only involved in the formation of intine but also in the formation of the initial framework for extine. Our results reveal how UDP-sugars regulate anther development and provide new clues for cellular ROS accumulation and PCD triggered by UDP-Glc as a signaling molecule.


Subject(s)
Oryza , Oryza/metabolism , Reactive Oxygen Species/metabolism , Apoptosis , Pollen/metabolism , Homeostasis , Sugars/metabolism , Uridine Diphosphate/metabolism , Gene Expression Regulation, Plant , Plant Proteins/genetics , Plant Proteins/metabolism
2.
Nature ; 577(7791): 492-496, 2020 01.
Article in English | MEDLINE | ID: mdl-31969724

ABSTRACT

Although two-dimensional (2D) atomic layers, such as transition-metal chalcogenides, have been widely synthesized using techniques such as exfoliation1-3 and vapour-phase growth4,5, it is still challenging to obtain phase-controlled 2D structures6-8. Here we demonstrate an effective synthesis strategy via the progressive transformation of non-van der Waals (non-vdW) solids to 2D vdW transition-metal chalcogenide layers with identified 2H (trigonal prismatic)/1T (octahedral) phases. The transformation, achieved by exposing non-vdW solids to chalcogen vapours, can be controlled using the enthalpies and vapour pressures of the reaction products. Heteroatom-substituted (such as yttrium and phosphorus) transition-metal chalcogenides can also be synthesized in this way, thus enabling a generic synthesis approach to engineering phase-selected 2D transition-metal chalcogenide structures with good stability at high temperatures (up to 1,373 kelvin) and achieving high-throughput production of monolayers. We anticipate that these 2D transition-metal chalcogenides will have broad applications for electronics, catalysis and energy storage.

3.
Small ; : e2309656, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38686693

ABSTRACT

Bi/CeO2 (BC-x) photocatalysts are successfully prepared by solvothermal loading Bi nanoparticles and Bi-doped CeO2 derived by Ce-MOF (Ce-BTC). Formaldehyde gas (HCHO) and tetracycline hydrochloride (HTC) are used to evaluate the photocatalytic activity of the synthesized Bi/CeO2. For BC-1000 photocatalyst, the degradation of HTC by 420 nm < λ < 780 nm light reaches 91.89% for 90 min, and HCHO by 350 nm < λ < 780 nm light reaches 94.66% for 120 min. The photocatalytic cycle experiments prove that BC-1000 has good cyclic stability and repeatability. The results of photoluminescence spectra, fluorescence lifetime, photocurrent response, and electrochemical impedance spectroscopy showed that the SPR (Surface Plasmon Resonance) effect of Bi nanoparticles acted as a bridge and promoted electron transfer and enhanced the response-ability of Bi/CeO2 to visible light. Bi-doping produced more oxygen vacancies to provide adsorption sites for adsorbing oxygen and generated more ·O2 - thus promoting photocatalytic reactions. The mechanism of photocatalytic degradation is analyzed in detail utilizing active free radical capture experiments and electron paramagnetic resonance (EPR) characterization. The experimental results indicate that ·O2 - and h+ active free radicals significantly promote the degradation of pollutants.

4.
Brain Behav Immun ; 123: 193-210, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39277023

ABSTRACT

The long-term high-fat, high-sugar diet exacerbates type 2 diabetes mellitus (T2DM)-related cognitive impairments. Phlorizin, a well-studied natural compound found in apples and other plants, is recognized for its bioactive properties, including modulation of glucose and lipid metabolism. Despite its established role in mitigating metabolic disorders, the neuroprotective effects of phlorizin, particularly against diabetes-related cognitive dysfunction, have not been fully elucidated. Therefore, the present study aimed to investigate the effect of dietary supplementation of phlorizin on high-fat and high-fructose diet (HFFD)-induced cognitive dysfunction and evaluate the crucial role of the microbiota-gut-brain axis. We found that dietary supplementation of phlorizin for 14 weeks effectively prevented glucolipid metabolism disorder, spatial learning impairment, and memory impairment in HFFD mice. In addition, phlorizin improved the HFFD-induced decrease in synaptic plasticity, neuroinflammation, and excessive activation of microglia in the hippocampus. Transcriptomics analysis shows that the protective effect of phlorizin on cognitive impairment was associated with increased expression of neurotransmitters and synapse-related genes in the hippocampus. Phlorizin treatment alleviated colon microbiota disturbance, mainly manifested by an increase in gut microbiota diversity and the abundance of short-chain fatty acid (SCFA)-producing bacteria. The level of microbial metabolites, including SCFA, inosine 5'-monophosphate (IMP), and D (-)-beta-hydroxybutyric acid (BHB) were also significantly increased after phlorizin treatment. Integrating multiomics analysis observed tight connections between phlorizin-regulated genes, microbiota, and metabolites. Furthermore, removal of the gut microbiota via antibiotics treatment diminished the protective effect of phlorizin against HFFD-induced cognitive impairment, underscoring the critical role of the gut microbiota in mediating cognitive behavior. Importantly, supplementation with SCFA and BHB alone mimicked the regulatory effects of phlorizin on cognitive function. Therefore, phlorizin shows promise as a potential nutritional therapy for addressing cognitive impairment associated with metabolic disorders. Further research is needed to explore its effectiveness in preventing and alleviating neurodegenerative diseases.

5.
Langmuir ; 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39150881

ABSTRACT

In this research, we used sum frequency generation vibrational spectroscopy to investigate the buried interface of a thiol-epoxy model aerospace sealant in contact with a silane-based adhesion promoter (6111) following exposures to 3% saltwater at elevated temperatures and elevated temperatures alone. The results suggest that the saltwater caused a change at the interface between the adhesion promoter and sealant, while an elevated temperature of 60 °C itself did not affect the interfacial structure noticeably. Model hydrolyzed and nonhydrolyzed silanes were also used in the study to compare with the adhesion promoter 6111 to understand the interfacial behavior of main silane components in 6111 as well as their potential role in adhesion. The amino silane in 6111 likely segregates more at the sealant/adhesion promoter interface and interacts with the sealant compared to the vinyl silane. The results imply that the saltwater immersion process led to the disordering of the adhesion promoter/sealant interface (caused by interfacial structural randomization), which could potentially have implications for adhesion.

6.
J Immunol ; 209(10): 2012-2021, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36426941

ABSTRACT

Germline-encoded pattern recognition receptors (PRRs) recognize molecules frequently found in pathogens (pathogen-associated molecular patterns [PAMPs]) during viral infection. This process induces production of IFNs, leading to expression of IFN-stimulated genes to establish a cellular antiviral state against viral infection. However, aberrant activation of the IFN system may cause immunopathological damage and systemic autoimmune diseases such as systemic lupus erythematosus. Stringent control of IFN signaling activation is critical for maintaining homoeostasis of the immune system; yet, the mechanisms responsible for its precise regulation remain to be elucidated. In this study, we identified that ring finger protein 215 (RNF215), a zinc finger protein, was upregulated by viral infection in human macrophages. In addition, we demonstrated that RNF215 inhibited the production of type I IFNs at least in part via interacting with p65, a subunit of NF-κB, and repressed the accumulation of NF-κB in the promoter region of IFNB1. Moreover, we found that the expression of RNF215 negatively correlated with type I IFNs in patients with systemic lupus erythematosus, indicating that RNF215 plays an important role in the pathogenesis of autoimmune diseases. Collectively, our data identified RNF215 as a key negative regulator of type I IFNs and suggested RNF215 as a potential target for intervention in diseases with aberrant IFN production.


Subject(s)
Autoimmune Diseases , Lupus Erythematosus, Systemic , Humans , Interferon Type I/biosynthesis , NF-kappa B , Pathogen-Associated Molecular Pattern Molecules , Signal Transduction
7.
BMC Pediatr ; 24(1): 437, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982398

ABSTRACT

BACKGROUND: Pilomatricoma (PM) is a cutaneous benign neoplasm derived from the hair matrix. It clinically presents as a solitary and firm nodule overlying normal epidermis and is usually not easy to be noticed at early stage. Nevertheless, when special bullous lesion occurs in a short time or even ulcerates, preoperative diagnosis by a dermatologist is often challenging especially when the pediatric patients refuse biopsy. CASE PRESENTATION: We present six bullous PM cases and particularly conduct correlation analysis on the dermotoscopy and histopathology detection data. The basic information, medical history, symptoms and lesion morphology results of the patients were also provided. We found that the incidence of bullous PM was higher in females than in males, and most patients were adolescents and the predilection location seem to be consistent in the vaccine injection site. The dermatoscopic features of bullous PM reported were luminous yellow structure below, with gray-blue homogeneous areas and branched capillary. The histological features were consistent with PM, and evident epidermis bullae were above the tumor with extraordinary dilation of lymphangion in the upper dermis. The patients described in this study were Chinese patients in Han population included 4 females and 2 males, coincidentally, they are almost teen-age, respectively are 5,11,17,19,21,22 year-old. CONCLUSIONS: This study reported and analyzed the dermotoscopy and clinical characteristics of bullous PM, dermotoscopy may guide as a rapid and reliable technique in bullous PM diagnosis.


Subject(s)
Dermoscopy , Hair Diseases , Pilomatrixoma , Skin Neoplasms , Humans , Male , Female , Adolescent , Pilomatrixoma/pathology , Pilomatrixoma/diagnosis , Skin Neoplasms/diagnosis , Skin Neoplasms/pathology , Hair Diseases/diagnosis , Hair Diseases/pathology , Child , Young Adult
8.
Planta ; 258(3): 66, 2023 Aug 17.
Article in English | MEDLINE | ID: mdl-37592053

ABSTRACT

MAIN CONCLUSION: Taxodium 703 leaves activate fermentation, amino acids metabolism and ROS detoxification, and reduce TCA cycle and ABA biosynthesis in acclimation to prolonged partial submergence stress. Taxodium hybrid 'Zhongshanshan 703' (T. mucronatum × T. distichum; Taxodium 703) is a highly flooding-tolerant woody plant. To investigate the physiological and transcriptional regulatory mechanisms underlying its leaves in acclimation to long-term flooding, we exposed cuttings of Taxodium 703 to either non-flooding (control) or partial submergence for 2 months. The leaf tissues above (AL) and below (BL) flooding-water were separately harvested. Partial submergence decreased concentrations of chlorophyll (a + b) and dehydroascorbate (DHA) and lactate dehydrogenase (LDH) activity in AL, and reduced biomass, concentrations of succinic acid, fumaric acid and malic acid, and transcript levels of genes involved in tricarboxylic acid (TCA) cycle in BL. Under partial submergence, concentrations of starch, malondialdehyde and abscisic acid (ABA) decreased, and also mRNA levels of nine-cis-epoxycarotenoid dioxygenases that are involved in ABA biosynthesis in AL and BL of Taxodium 703. Partial submergence increased O2- content in AL, and improved concentrations of pyruvate and soluble sugars and activities of LDH and peroxidase in BL. In addition, partial submergence increased concentrations of ethanol, lactate, alanine, γ-aminobutyric acid, total amino acids and ascorbic acid (ASA), and ASA/DHA, activities of alcohol dehydrogenases (ADH) and ascorbate peroxidase, as well as transcript levels of ADH1A, ADH1B and genes involved in alanine biosynthesis and starch degradation in AL and BL of Taxodium 703. Overall, these results suggest that Taxodium 703 leaves activate fermentation, amino acids metabolism and reactive oxygen species detoxification, and maintain a steady supply of sugars, and reduce TCA cycle and ABA biosynthesis in acclimation to prolonged partial submergence stress.


Subject(s)
Taxodium , Acclimatization , Fermentation , Alanine , Amino Acids , Ascorbic Acid
9.
Appl Opt ; 62(23): 6234-6240, 2023 Aug 10.
Article in English | MEDLINE | ID: mdl-37707092

ABSTRACT

A low F-number and 100% cold stop efficiency are beneficial for improving the performance of optical systems and have a wide range of applications in various thermal imaging scenarios. The cooled infrared coaxial four-mirror system can meet these two requirements, improve system integration, and reduce adjustment costs and difficulties. However, the secondary obstruction caused by the central hole of the third mirror will generate potential stray light. A structure model is proposed in which the primary mirror and the quaternary mirror are processed on the same mirror blank. In this model, a method is given to calculate system parameters using the obstruction ratio and magnification of each mirror. To evaluate the performance of the method, two design examples with different F-numbers (1.4, 1.0) were constructed. The influence of initial structural constraints on the exit pupil position and secondary obstruction was analyzed based on the design objectives of the examples. The aberrations were optimized by targeting the spot. In the optimization process, the incident coordinates and directions of the restricted edge field rays in the tertiary mirror and the quaternary mirror were limited to achieve control of the obstruction caused by the holes in the center of the mirrors. In the results, the RMS spot radius of the two design examples is smaller than the Airy disk radius, and the axial beam wavefront deviation RMS values are 0.026λ and 0.024λ, respectively. Moreover, the obstruction caused by the central holes of the mirrors is controlled within the given field of view. The results show that the proposed model and method can be used to design a low F-number cooled infrared coaxial four-mirror system and have good application prospects.

10.
Proc Natl Acad Sci U S A ; 117(38): 23869-23878, 2020 09 22.
Article in English | MEDLINE | ID: mdl-32907937

ABSTRACT

Mounting evidence has associated Zika virus (ZIKV) infection with congenital malformations, including microcephaly, which raises global alarm. Nonetheless, mechanisms by which ZIKV disrupts neurogenesis and causes microcephaly are far from being understood. In this study, we discovered direct effects of ZIKV on neural progenitor cell development by inducing caspase-1- and gasdermin D (GSDMD)-mediated pyroptotic cell death, linking ZIKV infection with the development of microcephaly. Importantly, caspase-1 depletion or its inhibitor VX-765 treatment reduced ZIKV-induced inflammatory responses and pyroptosis, and substantially attenuated neuropathology and brain atrophy in vivo. Collectively, our data identify caspase-1- and GSDMD-mediated pyroptosis in neural progenitor cells as a previously unrecognized mechanism for ZIKV-related pathological effects during neural development, and also provide treatment options for ZIKV-associated diseases.


Subject(s)
Brain Diseases , Neural Stem Cells , Pyroptosis/physiology , Zika Virus Infection , Zika Virus , Animals , Brain/cytology , Brain/metabolism , Brain/virology , Brain Diseases/metabolism , Brain Diseases/virology , Cells, Cultured , Humans , Mice , Microcephaly/metabolism , Microcephaly/virology , Neural Stem Cells/metabolism , Neural Stem Cells/virology , Zika Virus Infection/metabolism , Zika Virus Infection/virology
11.
Chaos ; 33(1): 013135, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36725626

ABSTRACT

In this paper, reverse transition entropy (RTE) is proposed and combined with refined composite multi-scale analysis and generalized fractional-order entropy to construct the refined composite multi-scale reverse transition generalized fractional-order complexity-entropy curve (RCMS-RT-GFOCEC). This measure aims to characterize and identify different complex time series. First, RTE is used to extract the static and dynamic transition probabilities of the temporal structure. Then, the distribution area and variation law of the visualization curves are adopted to characterize different time series. Finally, the time series are identified by the multi-scale curves of RTE, Hα min, and Cα max. The characteristic curves ( Hq min and Cq max) of the refined composite multi-scale q complexity-entropy curves (RCMS-q-CECs) for the comparative analysis are irregular. The experimental results indicate that the RCMS-RT-GFOCEC method could effectively characterize both artificial and empirical temporal series. Moreover, this method can effectively track the dynamical changes of rolling bearing and turbine gearbox time series. The accuracies of the proposed method reach 99.3% and 98.8%, while the recognition rates based on the RCMS-q-CEC method are only 95.7% and 97.8%, suggesting that the proposed method can effectively characterize and identify different complex temporal systems.

12.
Environ Monit Assess ; 195(10): 1163, 2023 Sep 07.
Article in English | MEDLINE | ID: mdl-37676307

ABSTRACT

Territorial space exhibits multiple functional attributes, which comprise production, living, and ecological functions usually. Optimizing the production-living-ecological space (PLES) has become the key to territorial and spatial planning; the scientific identification of the PLES lays a foundation for space optimization and has important guiding significance in territorial spatial zoning. To achieve the integration of macro-scale and micro-scale PLES, with the Urban Agglomeration in Central Yunnan as the research area in this study, the PLES functional identification systems from the administrative unit scale and the grid scale are constructed. The types of PLES are determined by integrating qualitative and quantitative evaluation results and using an improved primacy index model from a composite spatial perspective. On that basis, the division of comprehensive zoning is achieved for land use functions through kernel density analysis. As indicated by the results, the model is capable of reflecting the macro background of the PLES functions in administrative regions while characterizing the micro differences at the grid level in administrative units. There are significant differences in the production, living, and ecological functional spaces in the Urban Agglomeration. Production functions are concentrated in the central and northeastern, living functions are concentrated in the central, and ecological functions are concentrated in the western and northeastern, with significantly consistent or complementary spatial distributions of each other. The PLES of Urban Agglomeration includes production space (PS), ecological space (ES), production-living space (P-LS), production-ecological space (P-ES), living-ecological space (L-ES), and production-living-ecological space (P-L-ES), placing a focus on ES, P-ES, and P-L-ES, which marks significant differences in spatial distribution among different spatial types. The study area is divided into 24 functional zones, which are classified into 6 categories, and optimization paths are proposed. This study will provide a reference for territorial and spatial planning in spatial functional zoning, spatial pattern optimization, and land management applications.


Subject(s)
City Planning , Environmental Monitoring , China , Ecosystem
13.
Langmuir ; 37(43): 12705-12713, 2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34668715

ABSTRACT

A primer coating is engineered to facilitate compatibility between products like adhesives, sealants, and potting compounds and targeted substrates. Prolonged exposure of isocyanate-based primer surfaces to the environment is known to negatively affect the interfacial adhesion between itself and the products subsequently applied on top of it. However, the molecular behavior behind this observed phenomenon remained to be further investigated. In this study, sum frequency generation (SFG) vibrational spectroscopy, a nonlinear optical spectroscopic technique, was applied to study the surface of an isocyanate-based primer exposed to different environments at the molecular level. Atmospheric moisture was considered to be a potential factor in impairing the adhesion performance of the primer, and thus, time- and humidity-dependent experiments were executed to monitor the molecular behavior at the primer surface using SFG. In addition, 180° peel testing experiments were conducted to measure the adhesion properties of primers after being exposed to the corresponding conditions to correlate to SFG results and establish a chemical structure-macroscopic performance relationship. This study on the changes at the primer surface in different environments with varied humidity levels as a function of time aims to provide an in-depth understanding of the moisture effect on isocyanate-based primers. These learnings may also be helpful toward exploring a broader range of coatings and surface layers and improving customer product use guidelines.

14.
Org Biomol Chem ; 19(5): 988-992, 2021 02 07.
Article in English | MEDLINE | ID: mdl-33459332

ABSTRACT

A copper-catalyzed one-pot amine-alkylation of quinones with amines and alkanes in the presence of di-tert-butyl peroxide (DTBP) was developed via a radical reaction process. Various alkanes and aromatic or aliphatic amines with diverse structures and electronic properties are suitable substrates, and the chirality of amines can be maintained for the transformation. This method has high step and atom economy for straightforward access to aminated and alkylated quinones from readily available starting materials.

15.
Sensors (Basel) ; 21(8)2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33917254

ABSTRACT

To address the problem that the faults in axial piston pumps are complex and difficult to effectively diagnose, an integrated hydraulic pump fault diagnosis method based on the modified ensemble empirical mode decomposition (MEEMD), autoregressive (AR) spectrum energy, and wavelet kernel extreme learning machine (WKELM) methods is presented in this paper. First, the non-linear and non-stationary hydraulic pump vibration signals are decomposed into several intrinsic mode function (IMF) components by the MEEMD method. Next, AR spectrum analysis is performed for each IMF component, in order to extract the AR spectrum energy of each component as fault characteristics. Then, a hydraulic pump fault diagnosis model based on WKELM is built, in order to extract the features and diagnose faults of hydraulic pump vibration signals, for which the recognition accuracy reached 100%. Finally, the fault diagnosis effect of the hydraulic pump fault diagnosis method proposed in this paper is compared with BP neural network, support vector machine (SVM), and extreme learning machine (ELM) methods. The hydraulic pump fault diagnosis method presented in this paper can diagnose faults of single slipper wear, single slipper loosing and center spring wear type with 100% accuracy, and the fault diagnosis time is only 0.002 s. The results demonstrate that the integrated hydraulic pump fault diagnosis method based on MEEMD, AR spectrum, and WKELM methods has higher fault recognition accuracy and faster speed than existing alternatives.

16.
Small ; 16(35): e2003357, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32743967

ABSTRACT

Monolayer transition metal dichalcogenides are 2D materials with many potential applications. Chemical vapor deposition (CVD) is a promising method to synthesize these materials. However, CVD-grown materials generally have poorer quality than mechanically exfoliated ones and contain more defects due to the difficulties in controlling precursors' distribution and concentration during growth where solid precursors are used. Here, thiol is proposed to be used as a liquid precursor for CVD growth of high quality and uniform 2D MoS2 . Atomic-resolved structure characterizations indicate that the concentration of sulfur vacancies in the MoS2 grown from thiol is the lowest among all reported CVD samples. Low temperature spectroscopic characterization further reveals the ultrahigh optical quality of the grown MoS2 . Density functional theory simulations indicate that thiol molecules could interact with sulfur vacancies in MoS2 and repair these defects during the growth of MoS2 , resulting in high-quality MoS2 . This work provides a facile and controllable method for the growth of high-quality 2D materials with ultralow sulfur vacancies and high optical quality, which will benefit their optoelectronic applications.

17.
Pharmacol Res ; 161: 105131, 2020 11.
Article in English | MEDLINE | ID: mdl-32810628

ABSTRACT

Besides acting as principle cellular building blocks and energy reservoirs, lipids also carry important signals associated with many fundamental cell biological processes, such as proliferation, differentiation, migration, stress responses and cell demise. Hyperactive lipid metabolism is closely associated with cancer progression and unfavorable outcomes. The underlying mechanisms are being gradually deciphered. In this review, we aim to summarize recent advances on how reprogrammed lipid metabolism and accompanying signaling cascades directly modulate cancer cells, as well as influencing stromal cells and immune cells within the tumor microenvironment. For future studies, special attention should be paid to lipid-mediated crosstalk among cancer cells, their neighboring stromal cells, and immune cells, plus how these multi-level communications determine anti-tumor immunity and bring novel immunotherapeutic opportunities.


Subject(s)
Lipid Metabolism , Neoplasms/metabolism , Signal Transduction , Animals , Cell Communication , Humans , Neoplasms/immunology , Tumor Microenvironment
18.
Int J Neurosci ; 130(7): 700-707, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31902262

ABSTRACT

Background: Chlorogenic acid (CGA) has anti-oxidant and anti-inflammatory effects, but the study on its role in Alzheimer's disease (AD) models remains rare. Here, the effects of CGA on ß-amyloid protein (Aß)-induced cell models were investigated, aiming to provide a direction for Aß-induced AD.Material and methods: Hippocampal neurons were separated from newborn Sprague-Dawley (SD) rats and identified by immumofluorescence method. Hippocampal neurons were processed with Aß25-35 after pre-treatment CGA. MTT assay was used for detecting viability of treated cells. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and lactate dehydrogenase (LDH) of treated hippocampal neurons were determined by corresponding kits. Flow cytometry analysis assessed the apoptosis and mitochondrial membrane potential (MMP) in hippocampal neurons after treatment. The expressions of proteins related to apoptosis and endoplasmic reticulum stress (ERS) were measured by western blot (WB) analysis.Results: Immumofluorescence method showed that the Aß25-35 induction models were successfully constructed. CGA increased the viability and decreased the apoptosis rate of Aß25-35-induced hippocampal neurons. Decreasing activities of LDH and MDA, and raised contents of SOD and GSH-Px were appeared in Aß25-35-induced cells that pre-treated with CGA. Moreover, CGA also enhanced MMP intensity of hippocampal neurons induced by Aß25-35. In WB analysis, CGA reversed the promoting effect of Aß25-35 on the expressions of proteins related to pro-ERS and pro-apoptosis.Conclusion: CGA restrained the apoptosis of Aß25-35-induced hippocampal neurons via improving the anti-oxidant capacity, mitochondrial injury and ERS state of cells, which may provide a direction for AD.


Subject(s)
Amyloid beta-Peptides/toxicity , Antioxidants/administration & dosage , Apoptosis/drug effects , Chlorogenic Acid/administration & dosage , Hippocampus/drug effects , Hippocampus/metabolism , Neurons/drug effects , Neurons/metabolism , Peptide Fragments/toxicity , Animals , Cells, Cultured , Endoplasmic Reticulum Stress/drug effects , Female , Hippocampus/pathology , Male , Neurons/pathology , Rats, Sprague-Dawley
19.
Nano Lett ; 19(2): 1124-1130, 2019 02 13.
Article in English | MEDLINE | ID: mdl-30676030

ABSTRACT

Understanding the charge interaction between molecules and two-dimensional (2D) materials is essential for the design of functional devices. Here, we report the bifacial Raman enhancement of molecules on monolayer graphene and hexagonal boron nitride ( h-BN). Taking advantage of the atomically thick layered structure, we show that both surfaces of 2D materials can interact with molecules and simultaneously enhance their Raman scattering. Different enhancement features were observed for monolayer graphene and h-BN. The intensity decrease of particular Raman modes of copper phthalocyanine (CuPc) on both surfaces of h-BN suggests that z-dipoles exist and are partially canceled out between the two interfaces, while the twice Raman intensities of the characteristic Raman modes of CuPc on both surfaces of graphene compared to that on one surface evidenced the charge transfer process. These results provide an approach to modify 2D materials by bifacial adsorption of molecules, and the findings can inspire the design of functional 2D material-based devices.

20.
J Xray Sci Technol ; 28(2): 333-344, 2020.
Article in English | MEDLINE | ID: mdl-32083610

ABSTRACT

OBJECTIVE: To investigate the measurement reproducibility of the maximum diameter on MRI routine sequence (T1WI, T2WI, DWI) and CT in peripheral and central lung cancer, and to provide reference standard for evaluating treatment responses for lung cancer. METHODS: 53 patients with lung cancer underwent CT and 3.0T MR scanning. The maximum diameter was measured according to the RECIST1.1 standard on images of CT (lung and enhanced mediastinal window), MRI T2-BLADE, axial T1-VIBE and DWIb0, DWIb300, DWIb800, respectively. The reproducibility of the diameters was analyzed with intraclass correlation coefficient (ICC), and the distribution of measurement points with the Bland-Altman method. The difference analysis was assessed by paired samples t-test and nonparametric rank sum test, P < 0.05 is considered statistically significant. RESULTS: Reproducibility of diameters derived from routine MRI and CT was good (ICC > 0.75). For peripheral lung cancer, there was no significant difference in diameters between CT and MRI. While for central lung cancer, there was significant difference in diameters measured between using CT and each MRI sequence. However, the diameters derived from T1-VIBE and T2-BLADE were not significantly different from all DWI sequences. CONCLUSIONS: For peripheral lung cancer, the measurement on CT and routine MRI sequences can potentially replace each other after comprehensive consideration of examination purposes, but for central lung cancer, alternative use of CT and MRI in evaluating treatment responses for lung cancer should needs extra attention. The diameter measurement of lung cancer on DWI is consistent with that on T1WI and T2WI, suggesting that DWI can provide functional and morphological information.


Subject(s)
Lung Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Female , Humans , Lung/diagnostic imaging , Male , Middle Aged , Reproducibility of Results
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