Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 56
Filter
Add more filters

Country/Region as subject
Affiliation country
Publication year range
1.
Cereb Cortex ; 34(4)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38615239

ABSTRACT

How to achieve a high-precision suicide attempt classifier based on the three-dimensional psychological pain model is a valuable issue in suicide research. The aim of the present study is to explore the importance of pain avoidance and its related neural features in suicide attempt classification models among patients with major depressive disorder. By recursive feature elimination with cross-validation and support-vector-machine algorithms, scores from the measurements and the task-based EEG signals were chosen to achieve a suicide attempt classification model. In the multimodal suicide attempt classifier with an accuracy of 83.91% and an area under the curve of 0.90, pain avoidance ranked as the top one in the optimal feature set. Theta (reward positive feedback minus neutral positive feedback) was the shared neural representation ranking as the top one of event-related potential features in pain avoidance and suicide attempt classifiers. In conclusion, the suicide attempt classifier based on pain avoidance and its related affective processing neural features has excellent accuracy among patients with major depressive disorder. Pain avoidance is a stable and strong indicator for identifying suicide risks in both traditional analyses and machine-learning approaches. A novel methodology is needed to clarify the relationship between cognitive and affective processing evoked by punishment stimuli and pain avoidance.


Subject(s)
Depressive Disorder, Major , Humans , Suicide, Attempted , Pain , Evoked Potentials , Machine Learning
2.
Appl Opt ; 62(23): 6171-6179, 2023 Aug 10.
Article in English | MEDLINE | ID: mdl-37707086

ABSTRACT

With the development of computational imaging, the integration of optical system design and digital algorithms has made more imaging tasks easier to perform. Wavefront coding (WFC) is a typical computational imaging technique that is used to address the constraints of optical aperture and depth of field. In this paper, we demonstrated a low-cost and simple optical system based on WFC and deep learning. We constructed an optimized encoding method for the phase plate under the framework of deep learning, which reduces the requirement for aberration correction in the full field of view. Optical coding was achieved with just a double-bonded lens and a simple cubic phase mask, and digital decoding used the deep residual UNet++ network framework. The final image obtained has good resolution, whereas the depth of field of the system expanded by a factor of 13, which is of great significance for the high-precision inspection and attaching of small parts of machine vision.

3.
Molecules ; 28(15)2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37570750

ABSTRACT

Matrine is a quinoline alkaloid extracted and separated from the dried root, fruit, and other parts of the plant Sophora flavescens using an organic solvent. Matrine exhibits a variety of biological activities and is widely used in pharmacy, agronomy, and other fields. Due to its low bioavailability, poor chemical stability, and toxicity to the central nervous system, a large number of researchers have searched for matrine derivatives with higher biological activity and safety by modifying its structure. In this review article, the research progress of matrine derivatives obtained using two methods (extraction from Sophora flavescens and structural modifications) from 2018 to 2022 in terms of pharmacological activity, mechanism of action, and structure-activity relationship are presented. The modification of matrine over the past five years has been mainly on the D-ring. Many new matrine alkaloids have been extracted from natural products, some of which have good pharmacological activity, which broadens the strategy for matrine structural modification in the future.


Subject(s)
Biological Products , Matrines , Sophora flavescens , Matrines/chemical synthesis , Matrines/chemistry , Matrines/isolation & purification , Matrines/pharmacology , Biological Products/chemical synthesis , Biological Products/chemistry , Biological Products/isolation & purification , Biological Products/pharmacology , Sophora flavescens/chemistry , Plant Roots/chemistry , Fruit/chemistry , Structure-Activity Relationship , Humans , Animals , Cell Line
4.
Entropy (Basel) ; 25(1)2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36673202

ABSTRACT

Solving the eigenproblems of Hermitian matrices is a significant problem in many fields. The quantum resonant transition (QRT) algorithm has been proposed and demonstrated to solve this problem using quantum devices. To better realize the capabilities of the QRT with recent quantum devices, we improve this algorithm and develop a new procedure to reduce the time complexity. Compared with the original algorithm, it saves one qubit and reduces the complexity with error ϵ from O(1/ϵ2) to O(1/ϵ). Thanks to these optimizations, we can obtain the energy spectrum and ground state of the effective Hamiltonian of the water molecule more accurately and in only 20 percent of the time in a four-qubit processor compared to previous work. More generally, for non-Hermitian matrices, a singular-value decomposition has essential applications in more areas, such as recommendation systems and principal component analysis. The QRT has also been used to prepare singular vectors corresponding to the largest singular values, demonstrating its potential for applications in quantum machine learning.

5.
Opt Lett ; 46(18): 4538-4541, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34525044

ABSTRACT

Speckle correlation imaging (SCI) has found tremendous versatility compared with other scattering imaging approaches due to its single-shot data acquisition strategy, relatively simple optical setup, and high-fidelity reconstruction performance. However, this simplicity requires SCI experiments to be performed strictly in a darkroom condition. As background noise increases, the speckle contrast rapidly decreases, making precise interpretation of the data extremely difficult. Here, we demonstrate a method by refining the speckle in the autocorrelation domain to achieve high-performance single-shot imaging. Experiment results prove that our method is adapted to estimate objects in a low signal-to-background ratio (SBR) circumstance even if the SBR is about -23dB. Laboratory and outdoor SCI experiments are performed.

6.
Heart Surg Forum ; 24(3): E496-E501, 2021 Jun 10.
Article in English | MEDLINE | ID: mdl-34173737

ABSTRACT

BACKGROUND: Reducing the leg wound morbidity is crucial for the patients undergoing coronary artery bypass grafting (CABG) with great saphenous vein (SV) grafts harvested by no-touch (NT) technique. This study was to summarize the experience of skin bridging technique for reducing wound morbidity and the influence of it on one-year bypass graft patency. METHODS: According to skin bridging or not, harvesting times, graft length, number of bleeding branches, postoperative subjective perception assessment scale (ASEPSIS) scores and one-year patency rate were analyzed. RESULTS: From June 2018 to February 2019, 60 patients underwent CABG with SV grafts either with open-incision NT or skin bridging NT (30 in each group). There were no significant differences in age (71.4 ± 5.1 years vs. 68.9 ± 5.5 years) or graft length (23.3 ± 1.1 cm vs. 23.9 ± 1.3 cm) between the two groups. The bridging/NT group had a significantly longer harvest time (38.5 ± 4.9 min vs. 18.5 ± 2.6 min; P < 0.001) and a significantly greater number of bleeding branches (1.9 ± 1.2 vs. 0.8 ± 0.8; P < 0.001) than the open NT group. The open NT group had a significantly higher ASEPSIS score (23.8 ± 2.0 vs. 15.7 ± 2.6; P < 0.001). There was no significant difference in patency rate at one-year follow-up. CONCLUSION: Obtaining the SV by the combined NT/discontinuous skin bridging technique is a satisfactory method for patients who underwent CABG. This method has important clinical significance in reducing wound morbidity in the harvest of NT grafts.


Subject(s)
Coronary Artery Bypass/methods , Saphenous Vein/transplantation , Surgical Wound/epidemiology , Tissue and Organ Harvesting/methods , Vascular Patency/physiology , Wound Healing/physiology , Aged , China/epidemiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Morbidity/trends , Retrospective Studies , Saphenous Vein/physiopathology , Surgical Wound/prevention & control , Treatment Outcome , Vascular Surgical Procedures/methods
7.
J Environ Manage ; 292: 112717, 2021 Aug 15.
Article in English | MEDLINE | ID: mdl-34015611

ABSTRACT

As an effective emission reduction approach, CO2 capture and storage (CCS) combined with enhanced water recovery (EWR) technology can not only reduce CO2 emissions, but can also recover deep saline water resources to relieve pressure on regional water resources, and can ensure the energy supply and both social and economic development. However, the environmental benefits and application costs of CCS-EWR are uncertain, and are determined by the technology level, geological conditions, and other physical factors. In this study, an optimal source-sink matching model and a techno-economic assessment model were developed to evaluate the contributions of CCS-EWR to carbon emission reduction and the increase of the water supply by considering various uncertain factors, as well as the corresponding costs. In addition, the Yellow River Basin (YRB) in China was selected as the research region because, while there are abundant coal-fired power plants (CFPPs) in the YRB, the water resources are scarce. The results revealed the following. (1) The maximum CO2 capture capacity of the 236 CFPPs in the YRB is about 738.77 Mt/a, and nearly 13.14 Gt of fresh water could be provided until the 236 CFPPs in the YRB retire, which can partially relieve the pressure on the supply of water resources. (2) With the consideration of the CCS-EWR benefits, the average cost of the 236 CFPPs in the YRB in their residual lifetime to reduce their CO2 emissions by 90% will be no more than 180 CNY/t. (3) The incentive effect of the increase of the industrial water price on the profits of CCS-EWR projects is not significant. CCS-EWR technology has better application prospects in China under the dual constraints of carbon-neutral targets and water shortages, and more policy support is required for its deployment.


Subject(s)
Coal , Water , Carbon Dioxide/analysis , China , Coal/analysis , Power Plants , Rivers , Technology
8.
Entropy (Basel) ; 23(12)2021 Dec 08.
Article in English | MEDLINE | ID: mdl-34945955

ABSTRACT

The quantum search algorithm is one of the milestones of quantum algorithms. Compared with classical algorithms, it shows quadratic speed-up when searching marked states in an unsorted database. However, the success rates of quantum search algorithms are sensitive to the number of marked states. In this paper, we study the relation between the success rate and the number of iterations in a quantum search algorithm of given λ=M/N, where M is the number of marked state and N is the number of items in the dataset. We develop a robust quantum search algorithm based on Grover-Long algorithm with some uncertainty in the number of marked states. The proposed algorithm has the same query complexity ON as the Grover's algorithm, and shows high tolerance of the uncertainty in the ratio M/N. In particular, for a database with an uncertainty in the ratio M±MN, our algorithm will find the target states with a success rate no less than 96%.

9.
Can J Microbiol ; 66(5): 359-367, 2020 May.
Article in English | MEDLINE | ID: mdl-32053399

ABSTRACT

The magnitude of the impact of altitude gradient on microbial community and diversity has been studied in recent decades. Whereas bacteria have been the focus of most studies, fungi have been given relatively less attention. As a vital part of the macro- and microscopic ecosystem, rhizosphere fungi play a key role in organic matter decomposition and relative abundance of plant species and have an impact on plant growth and development. Using Duchesnea indica as the host plant, we examined the rhizosphere soil fungal community patterns across the altitude gradient in 15 sites of Yunnan province by sequencing the fungal ITS2 region with the Illumina MiSeq platform. We determined the fungal community composition and structure. We found that, surprisingly, rhizosphere soil fungal diversity of D. indica increased with altitudinal gradient. There was a slight difference in diversity between samples from high- and medium-altitude sites, with medium-altitude sites having the greater diversity. Furthermore, the rhizosphere soil fungal community composition and structure kept changing along the altitudinal gradient. Taxonomic results showed that the extent of phylum diversity was greatest at high-altitude sites, with Ascomycota, Basidiomycota, Zygomycota, and Glomeromycota as the most dominant fungal phyla.


Subject(s)
Altitude , Fungi/isolation & purification , Plant Roots/microbiology , Rosaceae/microbiology , Soil Microbiology , Biodiversity , China , Ecosystem , Mycobiome , Rhizosphere , Soil/chemistry , Temperature
10.
Curr Microbiol ; 77(8): 1724-1736, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32314037

ABSTRACT

The aim of this study was to compare the microbial community structure and diversity in powdery mildew-infected and noninfected strawberry plant rhizosphere soils in the greenhouse based on variations in the 16S rRNA gene V3-V4 and fungal ITS2 regions by Illumina amplicon sequencing. Powdery mildew infection reduced the number of operational taxonomic units (OTUs) and prokaryotic and fungal community richness/diversity indexes in the rhizosphere soils compared with those in healthy plant soils. Furthermore, 3543 prokaryotic and 581 fungal OTUs were obtained at the 97% similarity level. Proteobacteria, Actinobacteria, Bacteroidetes, Acidobacteria, and Chloroflexi were the dominant bacterial phyla; Woesearchaeota_DHVEG-6, Bathyarchaeota, and Thaumarchaeota were the dominant archaea; and Ascomycota, Basidiomycota, unclassified_fungi, and Zygomycota were the dominant fungal phyla. Their proportions differed significantly among samples. Wolbachia, Devosia, Pseudolabrys, Streptomyces, and Rhizomicrobium were the most abundant bacterial genera; their proportions differed significantly among samples. Most Pseudomonas, Streptomyces, and 'norank' group members might be potential antagonistic microorganisms of powdery mildew pathogens, and Wolbachia and Rickettsia might be pathogen-transmitting vectors. Microascus, Clitopilus, and Ciliophora were the dominant fungi, and their community structures and abundances significantly differed among samples. Microascus, Talaromyces, Zopfiella, and Cryptococcus were relatively more abundant in the powdery mildew-infected strawberry plant rhizosphere soils. Fusarium, Trichoderma, Clitopilus, and 'unclassified' group members may be potential antagonistic populations. The results suggested that powdery mildew-infected strawberry fruits and plants cannot be consumed. This report is the first study to illustrate differences in the rhizosphere soil prokaryotic and fungal communities between powdery mildew-infected and noninfected strawberry plants in a greenhouse.


Subject(s)
Fragaria/microbiology , Microbiota , Plant Diseases/microbiology , Rhizosphere , Soil Microbiology , Archaea/classification , Bacteria/classification , Biodiversity , High-Throughput Nucleotide Sequencing , Plant Roots/microbiology , RNA, Ribosomal, 16S/genetics
11.
Entropy (Basel) ; 22(8)2020 Jul 24.
Article in English | MEDLINE | ID: mdl-33286582

ABSTRACT

Besides Hermitian systems, quantum simulation has become a strong tool to investigate non-Hermitian systems, such as PT-symmetric, anti-PT-symmetric, and pseudo-Hermitian systems. In this work, we theoretically investigate quantum simulation of an anti-P-pseudo-Hermitian two-level system in different dimensional Hilbert spaces. In an arbitrary phase, we find that six dimensions are the minimum to construct the anti-P-pseudo-Hermitian two-level subsystem, and it has a higher success probability than using eight dimensions. We find that the dimensions can be reduced further to four or two when the system is in the anti-PT-symmetric or Hermitian phase, respectively. Both qubit-qudit hybrid and pure-qubit systems are able to realize the simulation, enabling experimental implementations in the near future.

12.
J Hum Genet ; 64(3): 249-252, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30504913

ABSTRACT

We identified a novel CCDC151 mutation, c.325G>T (p.E109X), in a patient with primary ciliary dyskinesia and situs inversus. This stopgain mutation was predicted to be disease causing by bioinformatics program (MutationTaster) and was also not presented in the current Genome Aggregation Database (gnomAD), Exome Aggregation Consortium (ExAC), Single Nucleotide Polymorphism Database (dbSNP), or National Heart, Lung, and Blood Institute (NHLBI) and Exome Sequencing Project (ESP). In addition, to the best of our knowledge, the present study was the first to report a CCDC151 mutation in primary ciliary dyskinesia patients with situs inversus in mainland China. In conclusion, our finding expands the spectrum of CCDC151 mutations, and more importantly our study provides additional support that CCDC151 plays important roles in left-right patterning and ciliary function.


Subject(s)
Carrier Proteins/genetics , Ciliary Motility Disorders/genetics , Exome Sequencing/methods , Exome/genetics , Mutation , Situs Inversus/genetics , Adult , Child , China , Ciliary Motility Disorders/pathology , Female , Humans , Male , Pedigree , Situs Inversus/pathology
13.
J Hum Genet ; 64(8): 829, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31178588

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
Environ Sci Technol ; 52(17): 9785-9792, 2018 09 04.
Article in English | MEDLINE | ID: mdl-30074775

ABSTRACT

Nitrous oxide (N2O) is widely used in radiation-chemistry and photochemistry as a scavenger to convert a hydrated electron ( eaq-) into a hydroxyl radical (·OH). However, few investigations pay attention to the photochemistry of dissolved N2O itself. The effects of purged N2O on photochemical processes are unclear and neglected. In the present work, the effects of N2O on the hydroxylation of terephthalic acid (TPA) were investigated with both medium-pressure and low-pressure mercury lamps as the light sources. Under short-wavelength UV (200-300 nm) irradiation, N2O accelerated the decay of TPA and the formation of 2-hydroxylterephthalic acid (hTPA). The effective quantum yield of ·OH from the photolysis of dissolved N2O at 254 nm was determined as 1.15-1.63, which was far larger than those of NO3- (0.09) and NO2- (0.046). On the basis of the kinetic analysis in N2 and N2O purged solutions, isotope fractionation with heavy oxygen water, and ·OH scavenging experiments with tert-butyl alcohol, the contribution of the ·OH radicals generated from the photolysis of N2O to the formation of hTPA (61.7%) was determined to be 1 order of magnitude higher than that from the converted eaq- (6.5%). These results demonstrate that using N2O and ·OH probes to quantify photogenerated eaq- in UVC irradiation might lead to false results. The work here is helpful for the proper design of scavenging and probing experiments by the combination of N2O and ·OH probes.


Subject(s)
Hydroxyl Radical , Nitrous Oxide , Kinetics , Photolysis , Water
15.
Med Sci Monit ; 24: 2158-2163, 2018 Apr 11.
Article in English | MEDLINE | ID: mdl-29637923

ABSTRACT

BACKGROUND Bupropion (BUP) is an antidepressant and its pharmacological activity is mediated by its major metabolite, hydroxybupropion (HBUP). We investigated the effects of genetic polymorphisms of CYP2B6 on BUP and HBUP to provide certain evidence on the clinical rational administration of BUP. MATERIAL AND METHODS Plasma BUP and HBUP concentrations were assayed using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). RESULTS A total of 23 healthy volunteers (eleven participants with CYP2B6*1/*1, 7 participants with CYP2B6*1/*6, 3 participants with CYP2B6*4/*6, and 2 participants with CYP2B6*1/*4) received orally administered 150 mg of BUP according to protocol. Blood samples were obtained up to 96 hours after administration. The whole blood was subject to genotyping by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The concentration-time curve (AUC(0→96)), maximum plasma concentration (Cmax), and terminal half-life (t1/2) values of BUP in CYP2B6*1/*4 were lower than those of CYP2B6*1/*1. By contrast, the time to Cmax (tmax) value of the former was higher than that of the latter. The HBUP AUC(0→96) values in CYP2B6*4/*6 and CYP2B6*1/*4 increased to values 1.12-fold and 1.98-fold, compared with CYP2B6*1/*1 carriers. However, the HBUP AUC(0→96) value in CYP2B6*1/*1 was 1.51-fold higher than that in CYP2B6*1/*6. Similarly, the HBUP Cmax values in CYP2B6*4/*6 and CYP2B6*1/*4 increased by 1.12-fold and 1.97-fold, whereas the HBUP Cmax value in CYP2B6*1/*6 decreased to a value 1.64-fold lower than that in CYP2B6*1/*1. CONCLUSIONS Genetic polymorphisms of CYP2B6 influence the pharmacokinetic parameters of BUP and HBUP and thus establish rational BUP administration for Chinese patients in clinical settings.


Subject(s)
Bupropion/analogs & derivatives , Bupropion/pharmacokinetics , Cytochrome P-450 CYP2B6/genetics , Adolescent , Adult , Area Under Curve , Asian People/genetics , Bupropion/blood , China , Chromatography, High Pressure Liquid , Cross-Over Studies , Cytochrome P-450 CYP2B6/metabolism , Genotype , Healthy Volunteers , Humans , Male , Polymorphism, Single Nucleotide/genetics , Tandem Mass Spectrometry , Young Adult
16.
Molecules ; 23(5)2018 May 16.
Article in English | MEDLINE | ID: mdl-29772722

ABSTRACT

Genus Cynanchum L. belongs to the family Asclepiadaceae, which comprise more than 200 species distributed worldwide. In Chinese medical practice, numerous drugs (such as tablets and powders) containing different parts of plants of this genus are used to treat snake bites, bruises, osteoblasts, rheumatoid arthritis and tumors. A search for original articles published on the cynanchum genus was performed by using several resources, including Flora of China Official Website and various scientific databases, such as PubMed, SciFinder, the Web of Science, Science Direct, and China Knowledge Resource Integrated (CNKI). Advances in the botanical, ethnomedicinal, phytochemical, and pharmacological studies of this genus are reviewed in this paper. Results showed that more than 440 compounds, including C21 steroids, steroidal saponins, alkaloids, flavonoids and terpene, have been isolated and identified from Cynanchum plants up to now. In vivo and in vitro studies have shown that plants possess an array of biological activities, including anti-tumor, neuroprotective and anti-fungal effects. Popular traditional prescription of Cynanchum sp. was also summed up in this paper. However, many Cynanchum species have received little or no attention. Moreover, few reports on the clinical use and toxic effects of Cynanchum sp. are available. Further attention should be focused on the study of these species to gather information on their respective toxicology data and relevant quality-control measures and clinical value of the crude extracts, active compounds, and bioactive metabolites from this genus. Further research on Cynanchum sp. should be conducted, and bioactivity-guided isolation strategies should be emphasized. In addition, systematic studies of the chemical composition of plants should be enhanced.


Subject(s)
Cynanchum/chemistry , Drugs, Chinese Herbal/pharmacology , Phytochemicals/pharmacology , Animals , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cynanchum/classification , Drugs, Chinese Herbal/chemistry , Ethnobotany , Ethnopharmacology , Flavonoids/chemistry , Flavonoids/pharmacology , Humans , Medicine, Traditional , Molecular Structure , Neuroprotective Agents/chemistry , Neuroprotective Agents/pharmacology , Phytochemicals/chemistry , Phytosterols/chemistry , Phytosterols/pharmacology
17.
Pharm Biol ; 55(1): 374-380, 2017 Dec.
Article in English | MEDLINE | ID: mdl-27931149

ABSTRACT

CONTEXT: CYP3A4 and P-gp together form a highly efficient barrier for orally absorbed drugs and always share the same substrates. Our previous work revealed that chrysosplenetin (CHR) significantly augmented the rat plasma level and anti-malarial efficacy of artemisinin (ART), partially due to the uncompetitive inhibition effect of CHR on rat CYP3A. But the impact of CHR on P-gp is still unknown. OBJECTIVE: The present study investigates whether CHR interferes with P-gp-mediated efflux of ART and elucidates the underlying mechanism. MATERIALS AND METHODS: P-gp-over-expressing Caco-2 cells were treated with ART (10 µM) or ART-CHR (1:2, 10:20 µM) in ART bidirectional transport experiment. ART concentration was determined by UHPLC-MS/MS method. Healthy male ICR mice were randomly divided into nine groups (n = 6) including negative control (0.5% CMC-Na solution, 13 mL/kg), ART alone (40 mg/kg), verapamil (positive control, 40 mg/kg), ART-verapamil (1:1, 40:40 mg/kg), CHR alone (80 mg/kg), ART-CHR (1:0.1, 40:4 mg/kg), ART-CHR (1:1, 40:40 mg/kg), ART-CHR (1:2, 40:80 mg/kg) and ART-CHR (1:4, 40:160 mg/kg). The drugs were administrated intragastrically for seven consecutive days. MDR1 and P-gp expression levels in mice small intestine were examined by performing RT-PCR and western blot analysis. ABC coupling ATPase activity was also determined. RESULTS: After combined with CHR (1:2), Papp (AP-BL) and Papp (BL-AP) of ART changed to 4.29 × 10 - 8 (increased 1.79-fold) and 2.85 × 10 - 8 cm/s (decreased 1.24-fold) from 2.40 × 10 - 8 and 3.54 × 10 - 8 cm/s, respectively. Efflux ratio (PBA/PAB) declined 2.21-fold (p < 0.01) versus to ART alone. ART significantly up-regulated both MDR1 mRNA and P-gp levels compared with vehicle, while CHR in combination ratio of 0:1, 0.1:1, 1:1, 2:1 and 4:1 with ART, reversed them to normal levels as well as negative control (p < 0.05). The ATPase activities in ART-CHR 1:4 and CHR alone groups achieved a slight increase (p < 0.05) when compared with ART alone. DISCUSSION AND CONCLUSION: These results confirm that CHR inhibited P-gp activity and reverse the up-regulated P-gp and MDR1 levels induced by ART. It suggested that CHR potentially can be used as a P-gp reversal agent to obstruct ART multidrug resistance.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B/antagonists & inhibitors , Artemisinins/metabolism , Colon/drug effects , Flavonoids/pharmacology , Intestine, Small/drug effects , RNA, Messenger/metabolism , ATP Binding Cassette Transporter, Subfamily B/genetics , ATP Binding Cassette Transporter, Subfamily B/metabolism , Animals , Biological Transport , Blotting, Western , Caco-2 Cells , Chromatography, High Pressure Liquid , Colon/metabolism , Drug Interactions , Drug Resistance, Multiple/drug effects , Humans , Intestine, Small/metabolism , Male , Mice, Inbred ICR , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Tandem Mass Spectrometry , Transfection , Up-Regulation , ATP-Binding Cassette Sub-Family B Member 4
18.
Biomed Chromatogr ; 30(10): 1582-90, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27012321

ABSTRACT

In this study, we used a self-contrast method, which excluded the individual difference, to evaluate the inhibitory effect of chrysosplentin (CHR) in the presence or absence of artemisinin (ART) on the P-glycoprotein (P-gp) transport activity. A sensitive and rapid UHPLC-MS/MS method was applied for quantification of digoxin, a P-gp-specific substrate, in rat plasma. A pharmacokinetic study was carried out: first after an oral administration of digoxin at a dose of 0.09 mg/kg (first period), followed by a 20-day wash-out, then after another administration of digoxin (second period). During the second period, test compounds were orally given three times per day for seven consecutive days. Results showed that the t1/2 of digoxin in all the groups had no significant difference between the first and second periods. The AUC0-24 , Cmax , tmax , and Clz /F of the negative control and ART alone groups showed no difference. However, the AUC0-24 and Cmax in the CHR alone, CHR-ART (1:2) and verapamil (positive control) groups showed 2.34-, 3.04-, 1.79-, and 1.81-, 1.99-, 2.06-fold increases along with 3.50-, 3.84- and 4.76-fold decreases for CLz /F, respectively. The tmax in the CHR-ART (1:2) group increased 3.73-fold. In conclusion, our self-contrast study suggested that CHR, especially when combined with ART in a ratio of 1:2, inhibited P-gp activity while ART alone has no effect. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Artemisinins/pharmacology , Digoxin/metabolism , Flavonoids/pharmacology , Animals , Area Under Curve , Artemisinins/pharmacokinetics , Biological Transport , Chromatography, High Pressure Liquid , Digoxin/administration & dosage , Flavonoids/pharmacokinetics , Male , Rats , Rats, Sprague-Dawley , Reference Standards , Tandem Mass Spectrometry
19.
Malar J ; 14: 432, 2015 Nov 04.
Article in English | MEDLINE | ID: mdl-26537009

ABSTRACT

BACKGROUND: Artemisinin (ART) is an efficacious and safe anti-malarial drugs but has low oral bioavailability and auto-induction profiles during multiple dosing. The pharmacokinetic disadvantages have been found to partially depend on the induction of cytochrome P-450 enzymes by ART and resulted in the therapeutic failure due to insufficient drug levels. The present study, therefore, investigated the impacts of chrysosplenetin (CHR), a polymethoxylated flavonoid from Artemisia annua, on the pharmacokinetics and the anti-malarial efficacy of ART against Plasmodium berghei. The inhibition of CHR on enzymatic activity of CYP1A2, CYP2A, CYP2C19, CYP2D6, CYP2E1, and CYP3A in rat liver microsome was also investigated. IC50, Km, Ki, and inhibitory type of CHR were respectively calculated. METHODS: Twenty rats were randomly divided into four groups and received three-day oral doses of ART in absence or presence of CHR (in ratio of 1:0, 1:1, 1:2, and 1:4, respectively). Plasma samples were separately harvested for ART pharmacokinetics analysis using a valid liquid chromatography tandem mass spectrometric (LC-MS/MS) method. Female Kunming mice were inoculated by P. berghei K173 strain and pre-exposed to three-day oral administration of ART with or without CHR as pharmacokinetics protocol. Giemsa staining method was applied to calculate percent parasitaemia (%) and inhibition (%). In vitro rat liver microsomal model was employed to elucidate the inhibitory effect of CHR on CYP1A2, CYP2A, CYP2C19, CYP2D6, CYP2E1, and CYP3A. RESULTS: The AUC0-t, Cmax, and t 1/2 of ART increased significantly (P < 0.05 or P < 0.01) as well as declined CLz (P < 0.05 or P < 0.01) after three-day oral doses of ART in presence of CHR (1:2) when compared with ART alone. Also, parasitaemia (%) remarkably attenuated 1.59 folds with 1.63-fold augmented inhibition (%) when the ratio between ART and CHR reached 1:2. CHR itself had no anti-malarial efficacy (P > 0.05). CHR inhibited in vitro activity of CYP1A2 and CYP2C19 (P < 0.01, IC50 = 4.61 and 6.23 µM) in a concentration-response manner. The inhibition did not emerge on CYP2E1 and CYP3A until the CHR concentration exceeded 4.0 µM (P < 0.01, IC50 = 28.17 and 3.38 µM). CHR has no impact on CYP 2A and CYP2D6 (P > 0.05). The inhibition types of CHR on CYP1A2 and CYP3A belonged to noncompetitive and uncompetitive, respectively. CONCLUSIONS: Co-administration of ART with CHR in ratio of 1:2 achieved a synergic anti-malarial effect partly because of the noncompetitive or uncompetitive inhibition of CHR of drug-metabolism enzymes, especially CYP3A which is closely related to the auto-induction of ART.


Subject(s)
Antimalarials/pharmacology , Artemisinins/pharmacology , Cytochrome P-450 Enzyme System/analysis , Enzyme Inhibitors/pharmacokinetics , Flavonoids/pharmacology , Malaria/drug therapy , Microsomes, Liver/enzymology , Animals , Antimalarials/pharmacokinetics , Artemisinins/pharmacokinetics , Chromatography, Liquid , Drug Synergism , Female , Male , Mice , Microsomes, Liver/drug effects , Plasma/chemistry , Plasmodium berghei/drug effects , Rats, Sprague-Dawley , Tandem Mass Spectrometry , Treatment Outcome
20.
Int J Clin Pharmacol Ther ; 52(10): 850-5, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25109411

ABSTRACT

OBJECTIVES: To evaluate the influence of CYP2C19*2/*3 and MDR1 C3435T polymorphisms on the pharmacokinetics of lansoprazole (LPZ) in healthy Chinese subjects. METHODS: All 24 subjects were from a study of bioequivalence. Plasma concentrations of LPZ were determined by liquid chromatography/mass spectrometry. Cytochrome P450 (CYP) 2C19*2/*3 and multidrug resistance transporter gene 1 (MDR1) C3435T of the subjects were genotyped by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: Significant differences were found in the area under the concentration-time curve from predose to T (AUC(0-T)), area under the concentration-time curve from predose to infinity (AUC(0-∞), t(1/2)), and apparent oral clearance (CL/F) of LPZ between CYP2C19 extensive metabolizers and intermediate metabolizers (p < 0.05). The AUC(0-T), AUC(0-∞), maximum plasma concentration, and CL/F of LPZ were significantly different between subjects with the MDR1 C3435T C/C, C/T, and T/T polymorphisms (p < 0.05). CONCLUSION: CYP2C19*2/*3 and MDR1 C3435T polymorphisms are important determinants of LPZ pharmacokinetics.


Subject(s)
Cytochrome P-450 CYP2C19/genetics , Lansoprazole/pharmacokinetics , Polymorphism, Genetic , ATP Binding Cassette Transporter, Subfamily B/genetics , Area Under Curve , Genotype , Humans
SELECTION OF CITATIONS
SEARCH DETAIL