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1.
Opt Express ; 31(20): 31982-31992, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37859011

ABSTRACT

Nitrite ion (NO2-) is a common contaminant that can significantly threaten human health and the environment. In this study, we demonstrate a chemical sensing platform to monitor the nitrite concentration using a fiber optofluidic laser (FOFL). An optical fiber, integrated into a microchannel, is used both as an optical micro-cavity and the sensing element. Rhodamine 6 G (Rh6G) in an aqueous micellar solution is used as the laser gain medium. The light intensity change of the lasing spectra is employed as an indicator for the NO2- ion concentration sensing. The lasing properties under different NO2- ion concentrations are experimentally and theoretically investigated to examine the sensing performance of the FOFL. The results show that the limit detection of the FOFL sensor is 0.54 µM, which is 2-order-of-magnitude lower than fluorescence measurement. The sensing mechanism of Rh6G for NO2- detection is studied by using density functional theory (DFT). The calculation results indicate that nitrite influences the electronic distribution of Rh6G based on the heavy atom effect, which leads to the fluorescence quenching of Rh6G in the excited state. In addition, the detection system exhibits favorable selectivity for NO2- ions.

2.
Analyst ; 148(20): 5050-5059, 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37668015

ABSTRACT

We report a fiber optofluidic laser (FOFL) using an RhB-doped ionic liquid (BmimPF6) as the gain medium and explore its application for large dynamic range highly sensitive pH sensing. Due to the high Q-factor of the FOFL and the unique merits of BmimPF6, lasing emission presents a threshold of only 0.61 µJ mm-1. Particularly, lasing emission behaviors are strongly dependent on the pH value of the gain medium, i.e., in the pH range 4.28-6.37, the lasing central wavelength blue-shifts monotonically with a sensitivity as high as 5.02 nm per pH unit, which we attribute to the conversion of the cationic form of RhB to the zwitterionic form caused by the deprotonation of the COOH group. Under alkaline conditions (pH 7.20-11.17), the lasing emission intensity exhibits a significant decrease and the corresponding lasing central wavelength is also blue-shifted due to the solvent effect. The sensitivity based on the wavelength shift is 3.03 nm per pH unit, which is 4-fold higher than that of fluorescence-based sensing, while the sensitivity based on the variation of the lasing emission intensity is almost three orders of magnitude higher than that of fluorescence-based sensing. Our work presents a novel dual sensing paradigm in response to different pH conditions, which can greatly improve the reliability and discrimination of pH sensing.

3.
Clin Lab ; 69(8)2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37560856

ABSTRACT

BACKGROUND: Regenerating gene (REG) family proteins play a pivotal role in cell proliferation, tissue regeneration, and tumor metastasis. Recent studies have concentrated on the role of REG proteins in pancreatic cancer, but the results remain controversial. In this study, a meta-analysis was performed to evaluate the precise diagnostic value of REG proteins in pancreatic cancer. METHODS: A search was conducted in PubMed, Medline, Embase, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Biomedical Literature Database (CBM), and WANFANG Data up to May 5, 2021. The QUADAS-2 tool was used to evaluate the quality of the included studies. The statistical analysis of the diagnostic tests was conducted using RevMan5 and Meta-Disc 1.4. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and their 95% confidence intervals (95% CIs) were calculated from each eligible study. RESULTS: The meta-analysis included 15 articles containing 796 patients and 584 controls. The pooled sensitivity was 0.71 (95% CI: 0.67 - 0.74), the pooled specificity was 0.73 (95% CI: 0.70 - 0.76), and the pooled DOR was 11.35 (95% CI: 5.92 - 21.77), respectively. The overall area under the receiver operating characteristic curve (AUC) was 0.84. Spearman's correlation coefficient was 0.34 (p = 0.221). For the subgroup analysis, the REG4 protein showed higher diagnostic accuracy compared with the other REG proteins. CONCLUSIONS: REG proteins have moderate diagnostic accuracy in pancreatic cancer. Further well-designed studies with larger sample sizes and clinical application are needed to validate the results of this meta-analysis.


Subject(s)
Pancreatic Neoplasms , Proteins , Humans , Pancreatic Neoplasms/diagnosis , ROC Curve , Biomarkers , Pancreatic Neoplasms
4.
Opt Express ; 30(13): 23295-23304, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-36225013

ABSTRACT

We report a whispering gallery mode (WGM)-based fiber optofluidic laser (FOFL), in which rhodamine B (RhB) in an aqueous surfactant solution of sodium dodecylbenzene sulfonate (SDBS) is used as the laser gain medium. Here, the role of SDBS is to scatter the RhB dye molecules to effectively prevent its self-association in the aqueous solution. Therefore, the fluorescence quantum yield of the used RhB dye is improved due to the enhanced solubilization, which results in a low lasing threshold of ∼2.2 µJ/mm2 when the concentration of SDBS aqueous solution reaches up to 20 mM, on par with or even better than most of the optofluidic dye lasers using RhB as the gain medium in an organic solution. We then establish a model of solubilization capacity of SDBS micelles, which successfully addresses the mechanisms of dye-surfactant interactions in the proposed FOFL system. We further apply this FOFL platform to the case of concentration sensing of the used SDBS, which exhibits a 2-order-of-magnitude improvement in sensitivity compared to the fluorescence measurement due to the signal amplification inherent to the lasing process. The proposed FOFL platform in combination with surfactant solubilization gain medium in an aqueous solution promises to enable chip-scale coherent light sources for various environmental and bio-chemical sensing applications.

5.
Nat Prod Res ; : 1-8, 2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36287603

ABSTRACT

Two new monoterpene esters, illigerates H and I (1 and 2), and six known compounds actinodaphine (3), bulbocupnine (4), stephanine (5), hypserpanine B (6), betulinic acid (7) and gallic acid (8) were obtained from the root of Illigera paviflora Dunn. Their structures were elucidated by spectroscopic analysis. Anti-inflammatory and α-glucosidase inhibitory activity of some isolated compounds were assessed. Two monoterpenes 1 and 2 exhibited weak in vitro anti-inflammatory activity (IC50 64.5 ± 5.3 and 79.2 ± 7.5 µM) while compounds 3-6 showed inhibition of α-glucosidase with IC50 values ranged from 87.17 to 118.74 µM.

6.
Opt Express ; 30(3): 4106-4116, 2022 Jan 31.
Article in English | MEDLINE | ID: mdl-35209655

ABSTRACT

We present a chip-scale integrated pH sensor with high sensitivity by using an optofluidic ring resonator (OFRR) laser. An optical fiber with a high refractive index (RI) is employed both as an optical cavity and the sensing reactor along a microchannel, while disodium fluorescein (DSF) aqueous solution with a low RI is served as the cladding gain medium and fluorescent probes. The pump light is introduced along the fiber axis and guided by the total internal reflection at the fiber/cladding interface. The evanescent field of the pump light extends out of the fiber surface and efficiently excites the dye molecules residing in the evanescent field region of the Whispering Gallery Modes (WGMs) of the OFRRs to produce lasing emission. This pumping scheme provides a uniform excitation to the gain medium and significantly increases the signal-to-noise ratio, ensuring a low lasing threshold and highly sensitive sensing. The lasing threshold property under different pH conditions is experimentally and theoretically conducted to evaluate the sensing performance, which shows that the lasing threshold highly depends on the pH value of the cladding solution due to the increasing deprotonation process. We further verify that the intensity of the lasing emission and the pH value shows good linearity in the pH range 6.51-8.13, with a 2-order-of-magnitude sensitivity enhancement compared to fluorescence measurement. The proposed OFRR lasing platform shows excellent robustness and low sample consumption, providing a powerful sensing strategy in medicine, and hazardous/toxic/volatile sensing, which require label-free, real-time, and in situ detection.

7.
J Microbiol Biotechnol ; 32(1): 91-98, 2022 Jan 28.
Article in English | MEDLINE | ID: mdl-34818665

ABSTRACT

Tetanus is a potentially fatal public health illness resulted from the neurotoxins generated by Clostridium tetani. C. tetani is not easily culturable and culturing the relevant bacteria from infected wounds has rarely been useful in diagnosis; PCR-based assays can only be conducted at highly sophisticated laboratories. Therefore, a real-time recombinase polymerase amplification assay (Exo-RPA) was constructed to identify the fragments of the neurotoxin gene of C. tetani. Primers and the exo probe targeting the conserved region were designed, and the resulting amplicons could be detected in less than 20 min, with a detection limit of 20 copies/reaction. The RPA assay displayed good selectivity, and there were no cross-reactions with other infectious bacteria common in penetrating wounds. Tests of target-spiked serum and pus extract revealed that RPA is robust to interfering factors and has great potential for further development for biological sample analysis. This method has been confirmed to be reliable for discriminating between toxic and nontoxic C. tetani strains. The RPA assay dramatically improves the diagnostic efficacy with simplified device architecture and is a promising alternative to real-time PCR for tetanus detection.


Subject(s)
Bacteriological Techniques/methods , Clostridium tetani/isolation & purification , Nucleic Acid Amplification Techniques/methods , Recombinases , Animals , Clostridium tetani/genetics , DNA Primers , Humans , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity , Tetanus/diagnosis , Tetanus/microbiology
8.
Org Lett ; 23(23): 9246-9250, 2021 12 03.
Article in English | MEDLINE | ID: mdl-34806895

ABSTRACT

The copper-catalyzed enantioselective C-H arylation between 2-arylindoles and hypervalent iodine reagents has been successfully developed, which provides a convenient and economical route to the highly atroposelective synthesis of axially chiral indole derivatives with a 2-aryl structure (up to 99% ee). Density functional theory calculations and wave function analysis show that the key "sandwich" intermediate leads to high enantioselectivity of the reaction.

9.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(2): 127-134, 2021 Feb 28.
Article in English, Chinese | MEDLINE | ID: mdl-33678648

ABSTRACT

OBJECTIVES: To explore the correlation between cytosine-phosphoric-guanylic (CpG) site of Septin 9 gene and colorectal cancer, and to develop a real-time PCR detection system in plasma in patients with colorectal cancer. METHODS: The methylation of training samples was detected by high-throughput sequencing technology, and the sites highly consistent with the clinical information of colorectal cancer were identified. Then the detection system of real-time PCR was designed to analyze the consistency of plasma and tissue based on methylationa sensitive enzyme digestion. Finally, 100 clinical trials were conducted to evaluate the performance of the detection system with the methylation sensitive enzyme digestion-real-time PCR. RESULTS: The highly consistent sites, which were selected by high-throughput sequencing from 71 training set samples, was the 38th CpG. Based on the detection region, the screened methylation sensitive enzymes were BstU1, HhaI and HinP1I. The limit for the detection of methylation sensitive enzyme digestion-real-time PCR was 0.5%, and the Ct value was 38.5. The sensitivity was 87.27%, the specificity was 91.49%, the positive predictive value was 92.31%, and the negative predictive value was 86.00%. CONCLUSIONS: The 38th CpG site of Septin 9 detected by the detection system of methylation sensitive enzyme digestion-real-time PCR can highly predict the occurrence of colorectal cancer with great clinical application value.


Subject(s)
Colorectal Neoplasms , Septins , Colorectal Neoplasms/genetics , CpG Islands/genetics , DNA , DNA Methylation , Humans , Plasma/metabolism , Septins/genetics , Septins/metabolism
10.
Nat Prod Res ; 35(6): 960-966, 2021 Mar.
Article in English | MEDLINE | ID: mdl-31135220

ABSTRACT

Two new monoterpene esters illigerates F and G (1 and 2) together with 5 know compounds illigerate A (3), illigerate C (4), actinodaphnine (5), N-methylactinodaphnine(6) and N-methyllaurotetanine(7) were isolated from Illigera aromatica S. Z. Huang et S. L. Mo. Their structures were identified by extensive NMR data and by comparing with the known compounds. The anti-inflammatory activity of four monoterpenes (1 - 4) was evaluated by inhibiting nitric oxide (NO) production in lipopolysaccharide-activated murine macrophage RAW 264.7 cells and four monoterpenoids exhibited inhibitory effect with IC50 values of 71.5 ± 7.3, 74.7 ± 5.6, 48.0 ± 7.4 and 65.1 ± 3.7 µM, respectively.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Esters/pharmacology , Hernandiaceae/chemistry , Monoterpenes/pharmacology , Plant Stems/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Aporphines/chemistry , Aporphines/isolation & purification , Aporphines/pharmacology , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Magnetic Resonance Spectroscopy , Mice , Monoterpenes/chemistry , Nitric Oxide/biosynthesis , RAW 264.7 Cells
11.
Anal Chem ; 92(22): 14983-14989, 2020 Nov 17.
Article in English | MEDLINE | ID: mdl-33108157

ABSTRACT

In this paper, we present the design and operation of a solid-core/liquid-cladding (SL) waveguide excited by an evanescent wave. To do this, an optical fiber is integrated into a microfluidic channel and pumped along the fiber axis, ensuring the cladding solution is excited by the evanescent field of the guided mode at the core/cladding interface. The pump beam is guided by the total internal reflection in the fiber, providing a uniform excitation along the microfluidic channel. The evanescent wave provides precise excitation to the dye molecules in close proximity to the core/cladding interface, which significantly reduces the background fluorescence and increases the signal-to-noise ratio. Fluorescence intensity measurements of different dye concentrations and refractive indices of the cladding solution are conducted to evaluate their influences on the propagation loss, which shows that the peak intensity propagation loss can be as low as about 0.1 dB/cm. We further exemplify that the intensity of the fluorescence emission and the dye concentration show good linearity when the dye is in the low concentration region (<250 µM). A broad-band and simultaneous light source with a single pump light is also demonstrated by employing cascade SL waveguide segments through fluorescence resonance energy transfer. The proposed SL waveguide demonstrates excellent robustness and is easy to fabricate and use, providing a versatile platform for a variety of applications, such as high-sensitivity detection of low-concentration samples, multiband on-chip light sources, and simultaneous measurement of multiplexed parameters.

12.
J Agric Food Chem ; 68(30): 7850-7860, 2020 Jul 29.
Article in English | MEDLINE | ID: mdl-32631058

ABSTRACT

Three new flavonoids, quercetin-3-O-6-[methyl-(S)-3-hydroxy-3-methylglutaroyl(1→6]-ß-d-glucopyranoside (1), kaempferol-3-O-[methyl-(S)-3-hydroxy-3-methylglutaroyl(1→6)]-ß-d-glucopyranoside (2), and quercetin-3-O-6-[(E)-4-methoxy-5-methylhexa-2,4-dienoatyl(1→6)]-ß-d-glucopyranoside (3), and two new alkaloids, 5-dehydroxymethyl-pyrrolemarumine 4″-O-α-l-rhamnopyranoside (4) and N1-methyl-N2-((4-O-α-l-rhamnopyranoside)benzyl) oxalamide (5), together with 45 known compounds (6-50) were isolated from the leaves of Moringa oleifera Lam. Among those compounds, 1-octacosanol (50), a straight-chain 28-carbon alcohol, exhibited good activity against diphenoxylate-induced constipation in mice, which is obtained as a laxative constituent from the plant for the first time. In order to have an accurate understanding of the content of compound 50, a quantification with gas chromatography-tandem mass spectrometry (GC-MS/MS) was carried out. The anti-inflammatory and α-glucosidase inhibitory activity of some compounds also was assessed.


Subject(s)
Laxatives/chemistry , Moringa oleifera/metabolism , Plant Extracts/chemistry , Plant Leaves/chemistry , Plant Leaves/metabolism , Flavonoids/chemistry , Flavonoids/metabolism , Gas Chromatography-Mass Spectrometry , Laxatives/metabolism , Moringa oleifera/chemistry , Plant Extracts/metabolism
13.
Opt Express ; 28(5): 6806-6819, 2020 Mar 02.
Article in English | MEDLINE | ID: mdl-32225920

ABSTRACT

A systematic design idea for liquid-filled cylindrical zoom lenses with ideal imaging quality over a wide focal length range is introduced in detail. The PWC method is used to calculate the initial structure parameters of the zoom lenses, and the optical design software ZEMAX is used to eliminate the spherical aberration at different focal lengths. Lenses named SLCL-Doublet are finally designed, which are formed by a symmetric liquid-core cylindrical lens (SLCL) filled with variable refractive index (RI) liquid and a doublet cylindrical lens capable of significantly weakening the spherical aberration. The focal length of the SLCL-Doublet continuously decreases from 101.406 mm to 54.162 mm as the liquid RI changes from 1.3300 to 1.5000. Calculated over 75% of the full aperture, the root mean square (RMS) spot radius of the SLCL-Doublet is always less than 7 µm over the whole focal length range, and the peak-to-valley wavefront error remains below the λ/4 limit when the focal length ranges from 62.373 mm to 65.814 mm, within which the lenses approach the diffraction limit, demonstrating improvement in the optical performance over that of previously designed liquid-core cylindrical lenses. The sources of potential fabrication and installation errors in the practical implementation of the SLCL-Doublet are also analyzed in detail. The SLCL-Doublet is demonstrated to be characterized by high imaging quality and easy installation, which enriches the types of core optical element for measuring the liquid RI and liquid diffusion coefficient and provides guarantee for improving the measurement accuracy.

14.
Anal Biochem ; 588: 113468, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31585097

ABSTRACT

Interleukin 6 (IL-6) is an interleukin that acts as both a proinflammatory and anti-inflammatory cytokine. It can be used as a potential diagnostic biomarker for sepsis. The aim of this study was to establish an easy-to-use detection kit for rapid, quantitative and on-site detection of IL-6. To develop the new IL-6 quantitative detecting kit, a double-antibody sandwich immunofluorescent assay was employed based on europium nanoparticles (Eu-np) combined with lateral flow immunoassay (LFIA). The performance of the new developed kit was evaluated in the aspects of parallel analysis, linearity, sensitivity, precision, accuracy, specificity and clinical sample analysis. Two-hundred and fourteen serum samples were used to carry out the clinical sample analysis. The new IL-6 quantitative detecting kit exhibited a wide linear range (2-500 pg/mL) and a good sensitivity (0.37 pg/mL). The intra-assay coefficient of variation (CV) and the inter-assay CV were 5.92%-8.87% and 7.59%-9.04%, respectively. The recovery rates ranged from 102% to 106%. Furthermore, a high correlation (n = 214, r = 0.9756, p < 0.01) was obtained when compared with SIEMENS CLIA IL-6 kit. Thus, the new quantitative method for detecting IL-6 has been successfully established. The results indicated that the newly-developed strip based on Eu-np combined with LFIA was a facile, fast, highly sensitive, low-cost, reliable biosensor and suitable for rapid and point-of-care test (POCT) for IL-6 in serum.


Subject(s)
Biosensing Techniques/methods , Fluorescent Antibody Technique, Direct/methods , Interleukin-6/blood , Europium/chemistry , Humans , Luminescent Agents/chemistry , Metal Nanoparticles/chemistry , Point-of-Care Testing , Sensitivity and Specificity
15.
J Biol Eng ; 13: 21, 2019.
Article in English | MEDLINE | ID: mdl-30886644

ABSTRACT

ABSTRACT: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a long non coding RNA (lncRNA) present in serum, is an important biomarker for detecting hepatocellular carcinoma (HCC). However, there are some shortcomings in current detection methods. So developing other novel MALAT1 detection methods is necessary. Electrochemical biosensors using different types of nanomaterials with various advantages may provide a suitable method for detection. Here, a new strategy for MALAT1 detection was proposed based on polyhedral nanogold-polyamide-amine dendrimers (PNG-PAMAMs). The SWCNH/Au composite was used as a capture probe immobilization matrix, and PNG-PAMAM was used as a trace label for the detection probe (DP). The strategy takes advantage of the ability of the surface of PNG to bind a capture probe whose sequence contains (GGG)3 trimer that can bind DNAzyme hemin. Moreover, PNG may carry abundant horseradish peroxidases (HRPs) to block excess nonspecific adsorption sites, with synergistic hemin catalysis. The results show that the biosensor provides ultrasensitive detection of MALAT1 with a remarkable catalytic effect. The enhanced biosensor has a detection limit of 0.22 fmol·mL- 1 for MALAT1, and the linear calibration of the biosensor ranged from 1 fmol·mL- 1 to 100 pmol·mL- 1. In addition, the electrochemical biosensor has desirable qualities compared to other detectors; for instance, it is inexpensive, highly stable, and sensitive and has good reproducibility. This assay was also successfully applied to the detection of MALAT1 in serum samples, demonstrating that the technology has potential application in the detection of MALAT1 for clinical HCC diagnosis. GRAPHICAL ABSTRACT: The schematic presentation ilustrates MALATI detection by biosensor with differential pulse stripping voltammetry. Polyhedral nanogold-PAMAM/horseradish peroxidases (PNG-PAMAM/HRP) detection probe with DNAzyme (hemin) sites was applied to determine MALATI. Signal was amplified by hemin/HRP/H2O2 catalytic system.

16.
EBioMedicine ; 44: 665-674, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30922964

ABSTRACT

BACKGROUND: Increasing evidence indicates that the gut microbiota contributes to the occurrence and development of metabolic diseases. However, little is known about the effects of commonly used antidiabetic agents on the gut microbiota. In this study, we investigated the roles of dipeptidyl peptidase-4 inhibitors (DPP-4i) and α-glucosidase inhibitor in modulating the gut microbiota. METHODS: 16S-rDNA sequencing was performed to analyse the effects of DPP-4i and acarbose on the gut microbiota in mice fed a high-fat diet (HFD). Fecal microbiota transplantation (FMT) from type 2 diabetes patients to germ-free mice was performed to investigate the contribution of the altered microbiome to antidiabetic effects of the drugs. Fecal metabolomics was also analysed by untargeted and targeted GC-MS systems. FINDINGS: Although DPP-4i and α-glucosidase inhibitor both altered the gut microbial composition, only the microbiome modulation of DPP-4i contributed to its hypoglycemic effect. Specifically, the changes of 68.6% genera induced by HFD were rescued by DPP-4i. FMT showed that the DPP-4i-altered microbiome improved glucose tolerance in colonized mice, while acarbose did not. Moreover, DPP-4i increased the abundance of Bacteroidetes, and also promoted a functional shift in the gut microbiome, especially increasing the production of succinate. INTERPRETATION: Our findings demonstrate an important effect of DPP-4i on the gut microbiota, revealing a new hypoglycemic mechanism and an additional benefit of it. Furthermore, modulating the microbial composition, and the functional shift arising from changes in the microbiome, might be a potential strategy for improving glucose homeostasis. FUND: This work was supported by grants from the National Natural Science Foundation of China (No. 81700757, No. 81471039, No. 81700714 and No. 81770434), the National Key R&D Program of China (No. 2017YFC1309602, No. 2016YFC1101100, No. 2017YFD0500503 and No. 2017YFD0501001), and the Natural Science Foundation of Chongqing (No. cstc2014jcyjjq10006, No. cstc2016jcyjA0093 and No. cstc2016jcyjA0518).


Subject(s)
Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Gastrointestinal Microbiome/drug effects , Glucose/metabolism , Homeostasis/drug effects , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Blood Glucose , Diabetes Mellitus, Type 2/metabolism , Diet, High-Fat , Disease Models, Animal , Glucose Tolerance Test , Humans , Insulin/metabolism , Male , Metagenome , Metagenomics/methods , Mice
17.
Planta Med ; 85(2): 112-117, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30278472

ABSTRACT

Four new coumestans dolichosins A - D (1: -4: ) were isolated from the roots of Dolichos trilobus, together with four known compounds: isosojagol (5: ), phaseol (6: ), psoralidin (7: ), and 4″,5″-dehydroisopsoralidin (8: ). Their structures were elucidated on the basis of spectroscopic data interpretation, mass spectrometric analyses, and the comparison with literature data of related compounds. The anti-inflammatory activity of these compounds (1: -8: ) was evaluated through the inhibition of nitric oxide production in lipopolysaccharide-activated murine macrophage RAW 264.7 cells, in which compounds 1: and 6: displayed moderate inhibitory activity and no cytotoxic effects. In a α-glucosidase inhibitory assay, compounds 1: and 5: -8: exhibited appreciable inhibition on α-glucosidase. Especially compounds 1, 7: , and 8: showed IC50 values lower than 20.0 µM.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Coumarins/pharmacology , Dolichos/chemistry , Glycoside Hydrolase Inhibitors/pharmacology , Plant Roots/chemistry , Animals , Anti-Inflammatory Agents/isolation & purification , Coumarins/isolation & purification , Glycoside Hydrolase Inhibitors/isolation & purification , Magnetic Resonance Spectroscopy , Mass Spectrometry , Mice , RAW 264.7 Cells/drug effects , alpha-Glucosidases/metabolism
18.
J Asian Nat Prod Res ; 21(6): 551-558, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30415578

ABSTRACT

Phytochemical investigation on Hemiphragma heterophyllum led to the isolation of two new compounds, heterophyllumin A (1) and heterophylliol (3), along with nine known compounds, (‒)-sibiricumin A (2), iridolactone (4), jatamanin A (5), dihydrocatalpolgenin (6), 25-hydroperoxycycloart-23-en-3ß-ol (7), 24-methylenecycloartanol (8), (+)-pinoresinol (9), hexadec-(4Z)-enoic acid (10), and 9,12, 15-octadecatrienoic acid (11). Their structures were elucidated on the basis of detailed spectroscopic analyses and by comparison with literature data. Further, the structure of compound 3 was unambiguously confirmed by single-crystal X-ray analysis. Some of those compounds showed moderate activity in the α-glucosidase inhibition assay.


Subject(s)
Iridoids/chemistry , Lignans/chemistry , Scrophulariaceae/chemistry , Spiro Compounds/chemistry , Drugs, Chinese Herbal , Glycoside Hydrolase Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/pharmacology , Iridoids/pharmacology , Lignans/pharmacology , Models, Molecular , Molecular Structure , Plant Extracts/chemistry , Spiro Compounds/pharmacology , X-Ray Diffraction
19.
Sci Rep ; 8(1): 12610, 2018 Aug 22.
Article in English | MEDLINE | ID: mdl-30135503

ABSTRACT

The mutual diffusion coefficient of heavy water in normal water is measured over a temperature range of 20 to 40 °C using a novel method called the shift of equivalent refractive index slice (SERIS). The measured values range from 1.9086 × 10-5 to 3.0860 × 10-5 cm2/s and fit the Arrhenius equation well, and the calculated data from the equation are consistent with the literature values obtained by the interference method. The SERIS method is based on a double liquid-core cylindrical lens (DLCL); the front liquid core of the DLCL is used as both a liquid diffusion cell and a key imaging lens, and the resolvable minimum of liquid refractive index is δn = 6.15 × 10-5. The rear liquid core is used as an aplanatic lens, and the transversal spherical aberration is less than 1 µm. The SERIS method provides a new way to measure mutual diffusion coefficients of liquid and has the following advantages: visual measurement, use of a simplified device, and easy operation.

20.
Opt Express ; 25(5): 5626-5640, 2017 Mar 06.
Article in English | MEDLINE | ID: mdl-28380819

ABSTRACT

We design and fabricate an aplanatic double liquid-core cylindrical lens (DLCL), which is used to measure the binary liquid diffusion coefficient (D). The front lens of the DLCL is used as both a diffusion cell and a key imaging element; the refractive index (RI) of liquid filled in its core can be measured in the way of spatial resolution. The rear lens of the DLCL is used as an aplanatic component, and either the RI position of spherical aberration (SA) or the SA in a range of RI caused by the front lens can be regulated by selecting the liquid, of which RI is pre-prepared and filled in the rear liquid core. Equipped with the aplanatic DLCL, two methods have been applied to measure the D value of 0.33mol/L KCL aqueous solution at temperature 298.15K. The first method derives D value precisely from the drift rate of diffusion image and the measured D is 1.8508 × 10-5 cm2/s. Meanwhile, the second method obtains the D value rapidly by analyzing an instantaneous diffusion image and the measured D is 1.8619 × 10-5 cm2/s. The measured values are in good agreement with the literature value, demonstrating that the designed DLCL works well in measuring liquid diffusion coefficients.

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