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1.
J Nutr Biochem ; 118: 109360, 2023 08.
Article in English | MEDLINE | ID: mdl-37087072

ABSTRACT

Vitamin D (VD) deficiency, as indicated by the main circulating form of VD metabolite 25-hydrovitamin D3 (25(OH)D3), in patients with Crohn's disease (CD) has been well documented, but the reasons for this remain unclear. In this study, 367 patients with CD and 57 healthy individuals who were enrolled, and the association between 25 (OH)D3 level and clinical biochemical characteristics including hepatic and renal functions, inflammatory response was analyzed with binary logistic regression models. VD metabolic enzymes and transporters were screened with bioinformatical analysis and identified with qRT-PCR and western blot. Compared to the healthy controls, serum 25(OH)D3 was significantly reduced in patients with CD, but the protein level of adenosine triphosphate (ATP)-binding cassette efflux transporter G2 (ABCG2) was evidently increased in the ileum and colon. Meanwhile, in lipopolysaccharide (LPS)-treated CaCO2 cells, the mRNA and protein levels of ABCG2 were significantly increased, and the overexpression of ABCG2 obviously promoted 25(OH)D3 efflux, but, Ko143, an ABCG2 inhibitors, substantially prevented the efflux of 25(OH)D3. In addition, in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced CD model mice, the ABCG2 protein levels were significantly increased in the ileum, colon, kidney and liver, and administration of Ko143 significantly inhibited the efflux of 25 (OH) D3in vivo. All of these findings suggest that VD deficiency in patients with CD may be associated with an abnormal increase in ABCG2 expression, but not directly implicated in hepatic and renal function, and inflammatory response in patients with CD.


Subject(s)
Crohn Disease , Vitamin D Deficiency , Humans , Mice , Animals , Caco-2 Cells , Liver/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics , ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , Neoplasm Proteins/metabolism
2.
Phytomedicine ; 112: 154679, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36791628

ABSTRACT

BACKGROUND: Although macrophage-mediated low-grade chronic inflammation and liver dysfunction have been found to be associated with the development of non-alcoholic fatty (NAFLD) and widely reported, but strategies and drugs targeting macrophages for the treatment of NAFLD are limited. HYPOTHESIS/PURPOSE: Garlic-derived exosomes (GDE) can be useful for NAFLD due to its anti-inflammatory activity. Clarify whether GDE improves liver dysfunction through macrophage-hepatocyte crosstalk. METHODS: GDE was isolated with PEG precipitation and ultracentrifuge. Inflammatory cytokines were detected by qRT-PCR and ELISA. Expression of 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3 (PFKFB3) was determined using qRT-PCR and western blot. Crosstalk between macrophages and hepatocytes was identified through a co-culture experiment. Small RNA sequencing and bioinformatic analysis were used to identify the key element of GDE regulating the expression of PFKFB3 gene. RESULTS: GDE regulated the expression of PFKFB3 to reduce the inflammatory response in LPS-treated differentiated THP-1 macrophages. Data from small RNA sequencing and bioinformatics analysis reveal that miR-396e, one of the most abundant miRNAs of GDE, is the key component to regulate PFKFB3 expression. Mechanistically, miR-396e-mediating PFKFB3 expression plays a crucial role in GDE inhibiting inflammatory response and enhancing lipid metabolism in hepatocytes via the macrophage-hepatocyte crosstalk. Notably, GDE supplementation reduced the inflammatory response and improved liver dysfunction in high-fat diet-fed mice. CONCLUSION: GDE may be useful for improving the symptoms of NAFLD via macrophage-hepatocyte crosstalk and its role in PFKFB3 expression.


Subject(s)
Exosomes , Garlic , MicroRNAs , Non-alcoholic Fatty Liver Disease , Animals , Mice , Diet, High-Fat , Exosomes/metabolism , Hepatocytes/metabolism , Macrophages/metabolism , Mice, Inbred C57BL , MicroRNAs/metabolism , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/metabolism
3.
Front Psychol ; 13: 919993, 2022.
Article in English | MEDLINE | ID: mdl-35814052

ABSTRACT

Based on the social exchange theory, this paper discusses the impact of high-performance work system (HPWS) on employee innovation behavior, constructs the mediating model of challenge stress and the moderated mediation model, and explores the influence mechanism of HPWS on employee innovation behavior under the management mode of combining strictness and love formed by "strictness" under the effect of challenge stress and "love" given by perceived organizational support. Through hierarchical regression analysis of 227 employees' survey data, the results show that HPWS positively influences employee innovation behavior. Challenge stress partially mediates the above relationship, and perceived organizational support positively moderates the mediating effect of challenge stress between HPWS and employee innovation behavior.

4.
Ann Palliat Med ; 11(3): 1135-1146, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35365044

ABSTRACT

Data in 2020 show that lung cancer is the second most common cancer with the highest morbidity and mortality in the world, among which small cell lung cancer (SCLC) accounts for about 15% of the total number of lung cancers, but the number of deaths accounts for 25% of lung cancers. SCLC is an aggressive malignancy disease with a high recurrence rate and poor prognosis. The survival rate of small cell lung cancer is lower than other types of lung cancer and the prognosis is very poor. At present, there is still a lack of effective therapeutic options for SCLC after the failure of second-line treatment. However, studies have shown that anti-vascular therapy and programmed death-1 (PD-1) inhibitors are effective in SCLC. In the present case, a combination therapy of camrelizumab, a PD-1 inhibitor, and anlotinib (an anti-angiogenic drug) was administered to treat a 58-year-old male patient with programmed cell death-Ligand 1 (PD-L1) negative metastatic SCLC accompanied by primary tongue cancer. A total of 28 cycles were used from March 2020 to November 2021. Until November 2021, the survival time of the patient is 31 months; he has survived for 19 months with no disease progression, and is currently classified as complete response (CR). Our study demonstrates that camrelizumab plus anlotinib may be a promising treatment option for patients with metastatic SCLC.


Subject(s)
Lung Neoplasms , Small Cell Lung Carcinoma , Antibodies, Monoclonal, Humanized/therapeutic use , Humans , Indoles , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Male , Middle Aged , Quinolines , Small Cell Lung Carcinoma/drug therapy
5.
Appl Biochem Biotechnol ; 180(7): 1446-1455, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27380420

ABSTRACT

Glutathione (γ-glutamyl-L-cysteinylglycine, GSH) is a pharmaceutical compound often used in food additives and the cosmetics industry. GSH can be produced biologically from L-glutamic acid, L-cysteine, and glycine through an enzymatic process traditionally involving two sequential adenosine triphosphate (ATP)-dependent reactions catalyzed by γ-glutamylcysteine synthetase (γ-GCS or GSHI, EC 6.3.2.2) and GSH synthetase (GS or GSHII, EC 6.3.2.3). Here, we report the enzymatic production of GSH by recombinant cell-free bifunctional γ-glutamylcysteine synthetase/glutathione synthetase (γ-GCS-GS or GshF) coupled with in vitro acetate kinase-based ATP generation. GSH production by an acetate kinase-integrated Escherichia coli Rosetta(DE3) mutant expressing Streptococcus thermophilus GshF reached 18.3 ± 0.1 g l-1 (59.5 ± 0.3 mM) within 3 h, with a molar yield of 0.75 ± 0.00 mol mol-1 added cysteine and a productivity of 6.1 ± 0.0 g l-1 h-1. This is the highest GSH titer reported to date. This newly developed biocatalytic process offers a promising approach for meeting the industrial requirements for GSH production.


Subject(s)
Acetate Kinase/metabolism , Adenosine Triphosphate/biosynthesis , Biotechnology/methods , Dipeptides/metabolism , Glutamate-Cysteine Ligase/metabolism , Glutathione Synthase/metabolism , Glutathione/biosynthesis , Escherichia coli/metabolism , Mutation/genetics , Streptococcus/enzymology
6.
Nanotechnology ; 25(18): 185705, 2014 May 09.
Article in English | MEDLINE | ID: mdl-24739789

ABSTRACT

This paper addresses a novel 3D reconstruction method for nanostructures based on the scanning electron microscopy (SEM) imaging principle. In this method, the shape from shading (SFS) technique is employed, to analyze the gray-scale information of a single top-view SEM image which contains all the visible surface information, and finally to reconstruct the 3D surface morphology. It offers not only unobstructed observation from various angles but also the exact physical dimensions of nanostructures. A convenient and commercially available tool (NanoViewer) is developed based on this method for nanostructure analysis and characterization of properties. The reconstruction result coincides well with the SEM nanostructure image and is verified in different ways. With the extracted structure information, subsequent research of the nanostructure can be carried out, such as roughness analysis, optimizing properties by structure improvement and performance simulation with a reconstruction model. Efficient, practical and non-destructive, the method will become a powerful tool for nanostructure surface observation and characterization.


Subject(s)
Imaging, Three-Dimensional/methods , Microscopy, Electron, Scanning/methods , Nanostructures , Humans , Models, Theoretical , Silicon
7.
Planta Med ; 80(5): 399-408, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24619838

ABSTRACT

Retinoic acid resistance results in refractory disease, and recovery in acute promyelocytic leukemia remains a challenge in clinical practice, with no ideal chemotherapeutic drug currently available. Here we report on the effect of an active compound of Sophora flavescens called matrine (0.1 mmol/L) combined with all-trans retinoic acid (1 µmol/L) in alleviating retinoic acid resistance in acute promyelocytic leukemia-derived NB4-LR1 cells by differentiation induction, as can be seen by an induced morphology change, increased CD11b expression, and nitro blue tetrazolium reduction activity, and a decreased expression of the promyelocytic leukemia-retinoic acid receptor α fusion gene and protein product. We further explored the probable mechanism of how matrine promotes the recovery of differentiation ability in NB4-LR1 cells when exposed to all-trans retinoic acid. We observed that the combination of all-trans retinoic acid and matrine can increase the level of cyclic adenosine monophosphate and protein kinase A activity, reduce telomerase activity, and downregulate the protein expression of topoisomerase II beta in NB4-LR1 cells. The results of this study suggest the possible clinical utility of matrine in the treatment of retinoic acid-resistant acute promyelocytic leukemia.


Subject(s)
Alkaloids/pharmacology , Cell Differentiation/drug effects , Leukemia, Promyelocytic, Acute/pathology , Quinolizines/pharmacology , Tretinoin/pharmacology , Base Sequence , Cell Line, Tumor , DNA Primers , Drug Synergism , Humans , Polymerase Chain Reaction , Matrines
8.
Biotechnol Lett ; 36(4): 835-41, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24322776

ABSTRACT

L-2-Aminobutyric acid (L-ABA) is an unnatural amino acid that is a key intermediate for the synthesis of several important drugs. It can be produced by transaminase or dehydrogenase from α-ketobutyric acid, which can be synthesized enzymatically from the bulk amino acid, L-threonine. Deamination of L-threonine followed by a hydrogenation reaction gave almost the theoretical yield and was estimated to be more cost-effective than the established chemical process. L-Threonine deaminase from Escherichia coli, L-leucine dehydrogenase from Bacillus cereus, and formate dehydrogenase from Pseudomonas sp. were over-expressed in E. coli and used for one-pot production of L-ABA with formate as a co-substrate for NADH regeneration. 30 mol L-threonine were converted to 29.2 mol L-ABA at 97.3 % of theoretical yield and with productivity of 6.37 g l(-1) h(-1) at 50 l. This process offers a promising approach to fulfil industrial requirements for L-ABA.


Subject(s)
Aminobutyrates/metabolism , Formate Dehydrogenases/metabolism , Leucine Dehydrogenase/metabolism , NAD/metabolism , Threonine Dehydratase/metabolism , Threonine/metabolism , Bacillus cereus/enzymology , Bacillus cereus/genetics , Escherichia coli/enzymology , Escherichia coli/genetics , Formate Dehydrogenases/genetics , Gene Expression , Leucine Dehydrogenase/genetics , Pseudomonas/enzymology , Pseudomonas/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Threonine Dehydratase/genetics
9.
Langmuir ; 29(34): 10769-75, 2013 Aug 27.
Article in English | MEDLINE | ID: mdl-23906343

ABSTRACT

This paper reports a novel single-step wafer-level fabrication of superhydrophobic micro/nano dual-scale (MNDS) poly(dimethylsiloxane) (PDMS) films. The MNDS PDMS films were replicated directly from an ultralow-surface-energy silicon substrate at high temperature without any surfactant coating, achieving high precision. An improved deep reactive ion etching (DRIE) process with enhanced passivation steps was proposed to easily realize the ultralow-surface-energy MNDS silicon substrate and also utilized as a post-treatment process to strengthen the hydrophobicity of the MNDS PDMS film. The chemical modification of this enhanced passivation step to the surface energy has been studied by density functional theory, which is also the first investigation of C4F8 plasma treatment at molecular level by using first-principle calculations. From the results of a systematic study on the effect of key process parameters (i.e., baking temperature and time) on PDMS replication, insight into the interaction of hierarchical multiscale structures of polymeric materials during the micro/nano integrated fabrication process is experimentally obtained for the first time. Finite element simulation has been employed to illustrate this new phenomenon. Additionally, hierarchical PDMS pyramid arrays and V-shaped grooves have been developed and are intended for applications as functional structures for a light-absorption coating layer and directional transport of liquid droplets, respectively. This stable, self-cleaning PDMS film with functional micro/nano hierarchical structures, which is fabricated through a wafer-level single-step fabrication process using a reusable silicon mold, shows attractive potential for future applications in micro/nanodevices, especially in micro/nanofluidics.


Subject(s)
Nanostructures/chemistry , Polymers/chemistry , Dimethylpolysiloxanes/chemistry , Microscopy, Electrochemical, Scanning , Nanostructures/ultrastructure , Surface Properties
10.
J Nanosci Nanotechnol ; 13(2): 1539-42, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23646678

ABSTRACT

In this paper, we present superhydrophobic micro/nano dual structures (MNDS). By KOH-etching of silicon, well-designed microstructures, including inverted pyramids and V-shape grooves, are first fabricated with certain geometry sizes. Nanostructures made of high-compact high-aspect-ratio nanopillars are then formed atop microstructures by an improved controllable deep reactive ion etching (DRIE) process without masks, thus forming MNDS. Resulting from both the minimized liquid-solid contact area and the fluorocarbon layer atop deposited during the DRIE process, the MNDS show a reliable superhydrophobicity. The contact angle and contact angle hysteresis are -165 degrees and less than 1 degrees, respectively. This superhydrophobicity of MNDS is very stable according to squeezing and dropping test, even in high voltage conditions with the electrowetting threshold voltage of -300 V. Therefore, this micro/nano dual-scale structure has strong potential applications to the self-cleaning surface and superhydrophobic micro/nano fluidics.

11.
Nano Lett ; 13(3): 1168-72, 2013 Mar 13.
Article in English | MEDLINE | ID: mdl-23384278

ABSTRACT

An attractive method to response the current energy crisis and produce sustainable nonpolluting power source is harvesting energy from our living environment. However, the energy in our living environment always exists in low-frequency form, which is very difficult to be utilized directly. Here, we demonstrated a novel sandwich-shape triboelectric nanogenerator to convert low-frequency mechanical energy to electric energy with double frequency. An aluminum film was placed between two polydimethylsiloxane (PDMS) membranes to realize frequency multiplication by twice contact electrifications within one cycle of external force. The working mechanism was studied by finite element simulation. Additionally, the well-designed micro/nano dual-scale structures (i.e., pyramids and V-shape grooves) fabricated atop PDMS surface was employed to enhance the device performance. The output peak voltage, current density, and energy volume density achieved 465 V, 13.4 µA/cm(2), and 53.4 mW/cm(3), respectively. This novel nanogenerator was systematically investigated and also demonstrated as a reliable power source, which can be directly used to not only lighten five commercial light-emitting diodes (LEDs) but also drive an implantable 3-D microelectrode array for neural prosthesis without any energy storage unit or rectification circuit. This is the first demonstration of the nanogenerator for directly driving biomedical microsystems, which extends the application fields of the nanogenerator and drives it closer to practical applications.

12.
Appl Microbiol Biotechnol ; 90(4): 1361-71, 2011 May.
Article in English | MEDLINE | ID: mdl-21360152

ABSTRACT

To further enhance repeated batch reactions with immobilized N-carbamoyl-D-amino acid amidohydrolase (DCase), which can be used for the industrial production of D-amino acids, the stability of high soluble mutant DCase-M3 from Ralstonia pickettii CGMCC1596 was improved by step-wise evolution. In our previous report, six thermostability-related sites were identified by error-prone PCR. Based on the above result, an improved mutant B5 (Q12L/Q23L/H248Q/T262A/T263S) was obtained through two rounds of DNA shuffling, showing a 10°C increase in the T (50) (defined as the temperature at which heat treatment for 15 min reduced the initial activity by 50%) compared with the parental enzyme DCase-M3. Furthermore, several thermostability-related sites (Met(31), Asn(93), Gln(207), Asn(242), Glu(266), Thr(271), Ala(273)) on B5 were identified using amino acid consensus approach based on sequence alignment of homologous DCases. These sites were further investigated by iterative saturation mutagenesis (ISM), and a combinational mutant D1 (Q12L/Q23L/Q207E/N242G/H248Q/T262A/T263S/E266D/T271I/A273P) that enhanced the T(50) by about 16°C over DCase-M3 was obtained. Oxidative stability assay showed that the most heat-resisting mutant displayed only a slight increase in resistance to hydrogen peroxide. Comparative characterization showed that D1 not only maintained its characteristic high solubility but also shared similar k(cat) and K(m) values and optimum reaction pHs with the parental enzyme. The significantly improved mutants in the immobilized form are expected to be applied in the industrial production of D-p-hydroxyphenylglycine.


Subject(s)
Amidohydrolases/chemistry , Amidohydrolases/genetics , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Mutation , Ralstonia pickettii/enzymology , Amidohydrolases/metabolism , Amino Acid Sequence , Amino Acid Substitution , Bacterial Proteins/metabolism , Enzyme Stability , Hot Temperature , Kinetics , Models, Molecular , Molecular Sequence Data , Mutagenesis, Site-Directed , Ralstonia pickettii/chemistry , Ralstonia pickettii/genetics
13.
Phys Chem Chem Phys ; 8(23): 2720-6, 2006 Jun 21.
Article in English | MEDLINE | ID: mdl-16763704

ABSTRACT

PtRu/Ti anodes with varying Pt ratio Ru ratio were prepared by electrodeposition of a thin PtRu catalyst layer onto Ti mesh for a direct methanol fuel cell (DMFC). The morphology and structure of the catalyst layers were analyzed by SEM, EDX and XRD. The catalyst coating layer shows an alloy character. The relative activities of the PtRu/Ti electrodes were assessed and compared in half cell and single DMFC experiments. The results show that these electrodes are very active for the methanol oxidation and that the optimum Ru surface coverage was ca. 9 at.% for DMFC operating at 20 degrees C and 11 at.% at 60 degrees C. The PtRu/Ti anode shows a performance comparable to that of the conventional carbon-based anode in a DMFC operating with 0.25 M or 0.5 M methanol solution and atmosphere oxygen gas at 90 degrees C.


Subject(s)
Electric Power Supplies , Methanol/chemistry , Platinum/chemistry , Ruthenium/chemistry , Titanium/chemistry , Electrodes , Electroplating , Surface Properties
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