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1.
Int J Biol Macromol ; 253(Pt 2): 126743, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37689290

ABSTRACT

Cellulose nanocrystals (CNCs) are green reinforcing materials, and their potential has been evaluated in the preparation of waterborne UV-curable resin composites with high-performance. Herein, we present a novel and scalable approach for preparing surface-modified CNCs with acrylic-based polymers to strengthen the compatibility and interaction between CNCs and UV-curable resins. Using tert-butyl acrylate as the monomer, the nanocellulose grafted copolymer CNC-g-PtBA was successfully synthesized via atom transfer radical polymerization (ATRP) in the presence of a macromolecular initiator. Then, the CNC-g-PtBA is blended into the acrylic resin as a nanofiller to prepare the UV-curable nanocomposite. The results indicated that the contact angle of the CNCs increased from 38.7° to approximately 74.8°, and their thermal stability was significantly improved after graft modification. This contributed to the effective alleviation of the agglomeration phenomenon of nanocomposites due to the high hydrophilicity of pure CNCs. Notably, not only was the UV curing efficiency of the nanocomposites greatly increased but the mechanical properties were also further enhanced. Specifically, with the addition of 0.5 wt% CNC-g-PtBA, the curing time of the nanocomposite was shortened from >30 mins down to approximately 6 mins, and the bending strength was increased from 10 MPa for the original resin and 5 MPa for the addition of pure CNCs to 14.3 MPa, and the bending modulus was also greatly increased (up to approximately 730 MPa). Compared to pure CNCs, they are compatible with the resin, exhibiting high mechanical strength and flexibility, and have virtually no effect on the light transmission of the nanocomposites. Additionally, dielectric analysis (DEA) was used to monitor the dielectric constant and conductivity of the UV-curable nanocomposites in real time to further characterize their curing kinetics. The permittivity of these nanocomposites increased by 125 % compared to pristine resin, which shows potential for applications in high dielectric composites or for improving electrical conductivity. This work provides a feasible method for preparing UV-curable nanocomposites with high curing efficiency and permittivity, realizing a wider application of this high-performance nanocomposite.


Subject(s)
Nanocomposites , Nanoparticles , Polymerization , Polymers , Nanoparticles/chemistry , Nanocomposites/chemistry
2.
Materials (Basel) ; 16(16)2023 Aug 13.
Article in English | MEDLINE | ID: mdl-37629897

ABSTRACT

This study investigates the UV degradation of black Chinese lacquer by incorporating carbon black and ferrous hydroxide as additives. The purpose of this research is to understand the effects of these additives on the degradation behavior of the lacquer film. Different concentrations of carbon black powder (1%, 3%, and 5%) and Fe(OH)2 (10%, 20%, and 30%) were added to the lacquer following traditional techniques. The main methods employed for analysis were gloss loss measurement, color change assessment, SEM imaging, FTIR spectroscopy, and XPS analysis. The results demonstrate a significant decrease in gloss levels and an increase in lightness values with increasing ultraviolet exposure time. SEM images reveal the formation of cracks in the lacquer film. FTIR analysis indicates oxidation of the urushiol side chain and an increase in oxidation products. The infrared difference spectrum highlights the differences between the additives, with Fe(OH)2 showing a lower impact on the spectra compared to carbon black. XPS analysis confirms the oxidation of the C-H functional group and the presence of C-O-C and C-OH groups. In conclusion, this study sheds light on the influence of carbon black and ferrous hydroxide additives on the UV degradation of black Chinese lacquer and suggests the protective effect of Fe(OH)2 against UV aging. These findings contribute to a better understanding of the degradation mechanisms and provide insights for improving the UV resistance of Chinese lacquer coatings. Further research can explore alternative additives and optimization strategies to mitigate UV-induced degradation.

3.
Anim Biosci ; 36(9): 1367-1375, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37402463

ABSTRACT

OBJECTIVE: Pigment production and distribution are controlled through multiple proteins, resulting in different coat color phenotypes of sheep. METHODS: The expression distribution of vimentin (VIM) and transthyretin (TTR) in white and black sheep skins was detected by liquid chromatography-electrospray ionization tandem MS (LC-ESI-MS/MS), gene ontology (GO) statistics, immunohistochemistry, Western blot, and quantitative real time polymerase chain reaction (qRT-PCR) to evaluate their role in the coat color formation of sheep. RESULTS: LC-ESI-MS/MS results showed VIM and TTR proteins in white and black skin tissues of sheep. Meanwhile, GO functional annotation analysis suggested that VIM and TTR proteins were mainly concentrated in cellular components and biological process, respectively. Further research confirmed that VIM and TTR proteins were expressed at significantly higher levels in black sheep skins than in white sheep skins by Western blot, respectively. Immunohistochemistry notably detected VIM and TTR in hair follicle, dermal papilla, and outer root sheath of white and black sheep skins. qRT-PCR results also revealed that the expression of VIM and TTR mRNAs was higher in black sheep skins than in white sheep skins. CONCLUSION: The expression of VIM and TTR were higher in black sheep skins than in white sheep skins and the transcription and translation were unanimous in this study. VIM and TTR proteins were expressed in hair follicles of white and black sheep skins. These results suggested that VIM and TTR were involved in the coat color formation of sheep.

4.
Quant Imaging Med Surg ; 13(4): 2697-2707, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37064397

ABSTRACT

Background: The aim of this study was to investigate the value of unenhanced magnetic resonance imaging (MRI) with diffusion kurtosis imaging (DKI) in diagnosing papillary thyroid carcinoma (PTC). Methods: In all, 77 consecutive patients comprising a total of 77 thyroid nodules were enrolled in this study. Of these nodules, 41 were histopathologically confirmed PTCs and 36 were benign nodules. All patients underwent thyroid MRI including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and DKI. All the images were assessed by 2 radiologists. The signal intensity ratio (SIR) of these nodules on T1WI and T2WI, the apparent diffusion coefficient (ADC) from DWI, and mean diffusivity (MD) and mean kurtosis (MK) from DKI were measured. Morphological features on these images were also evaluated. Univariate and multivariate logistic regression analyses were used to evaluate the value of these parameters as potential predictors of PTC. Results: In the univariate analyses, the features that significantly indicated PTC were decreased ADC value (P<0.001), decreased MD value (P<0.001), increased MK value (P<0.001), younger age (P=0.001), female tendency (P=0.049), smaller tumor diameter (P<0.001), solid component (P<0.001), and irregular margin (P<0.001). In the multivariate analysis, decreased MD value (odds ratio =25.321; P=0.001), smaller diameter (odds ratio =13.751; P=0.006), and irregular margin (odds ratio =16.003; P=0.003) were independent risk factors for PTC. The combined predictor of MD, diameter, and margin showed an area under the receiver operating characteristic (ROC) curve of 0.996 in diagnosing PTC, with an optimal cutoff value of 0.69 (95.1% sensitivity, 100.0% specificity). Conclusions: Lower MD value from DKI, smaller diameter, and irregular margin are useful predictive biomarkers for PTC.

5.
Materials (Basel) ; 16(3)2023 Jan 29.
Article in English | MEDLINE | ID: mdl-36770151

ABSTRACT

Luoyang No.1 is a Qing Dynasty (1644-1902) inland river ancient wooden shipwreck discovered in September 2013. It adds significantly to the study of Grand Canal transport history and Luoyang's economic history. The wood characteristics of Luoyang No.1 were investigated in this study using chemical compositions, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nano-indentation (NI), and scanning electron microscopy (SEM). The results showed that the holocellulose content was only 32.84-37.69%, indicating that the cellulose and hemicellulose had been seriously degraded. Based on the XRD pattern, the degree of crystallinity of cellulose in wood ranged from 19.82 to 22.83%. The nano-indentation demonstrated that compared with the undegraded contemporary wood, the elastic modulus and hardness of the ancient ship wood decreased by 45.5% and 32.1%, respectively. Furthermore, the FTIR spectra revealed that the biological deterioration of ancient wood was indicated by a decrease in the peaks related to cellulose and hemicellulose, but the change in lignin was insignificant. The results could provide knowledge for appropriate dewatering, strengthening, restoration strategies and regulation of the museum environment.

6.
Nano Lett ; 23(3): 872-879, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36662599

ABSTRACT

The kagome metal CsV3Sb5 features an unusual competition between the charge-density-wave (CDW) order and superconductivity. Evidence for time reversal symmetry breaking (TRSB) inside the CDW phase has been accumulating. Hence, the superconductivity in CsV3Sb5 emerges from a TRSB normal state, potentially resulting in an exotic superconducting state. To reveal the pairing symmetry, we first investigate the effect of nonmagnetic impurity. Our results show that the superconducting critical temperature is insensitive to disorder, pointing to conventional s-wave superconductivity. Moreover, our measurements of the self-field critical current (Ic,sf), which is related to the London penetration depth, also confirm conventional s-wave superconductivity with strong coupling. Finally, we measure Ic,sf where the CDW order is removed by pressure and superconductivity emerges from the pristine normal state. Our results show that s-wave gap symmetry is retained, providing strong evidence for the presence of conventional s-wave superconductivity in CsV3Sb5 irrespective of the presence of the TRSB.

7.
Materials (Basel) ; 16(2)2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36676247

ABSTRACT

Huaguangjiao I refers to the ancient Chinese wooden shipwreck of the South Song Dynasty (1127-1279 AD) discovered in the South China Sea in 1996. From 2008 to 2017, the archaeological waterlogged wood was desalted using deionized water combined with ultrasonic treatment, and desalted using EDTA-2Na, EDTAHO, and NaH2PO4·2H2O solutions. In this paper, the degree of degradation of the modified waterlogged archaeological wood and the moisture and content of the main components were determined. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nanoindentation (NI), and scanning electron microscopy (SEM) were employed to investigate the state of wood degradation after desalination and desulfurization. The results showed that the water content of the wood was as high as 532~1149%, while the basic density was only 0.14~0.18 g/cm3, indicating that the wood had been seriously degraded. The holocellulose content was only 36-40%. Based on the XRD patterns, the degree of cellulose crystallinity in the modified wood was 14.08%. The elastic modulus and hardness of the ancient shipwreck wood after desalination and desulfurization were 1.28-4.31 and 0.10-0.28 GPa, respectively, according to nanoindentation. In addition, the FTIR spectra revealed that the biological deterioration of the modified wood caused cellulose and hemicellulose degradation, but no apparent lignin alteration occurred. The results could provide knowledge for appropriate dewatering, strengthening, and restoration strategies.

8.
Rev Sci Instrum ; 93(8): 083912, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-36050123

ABSTRACT

Quantum materials exhibit intriguing properties with important scientific values and huge technological potential. Electrical transport measurements under hydrostatic pressure have been influential in unraveling the underlying physics of many quantum materials in bulk form. However, such measurements have not been applied widely to samples in the form of thin flakes, in which new phenomena can emerge, due to the difficulty in attaching fine wires to a thin sample suitable for high-pressure devices. Here, we utilize a home-built direct laser writing system to functionalize a diamond anvil to directly integrate the capability of conducting electrical transport measurements of thin flakes with a pressure cell. With our methodology, the culet of a diamond anvil is equipped with a set of custom-designed conducting tracks. We demonstrate the superiority of these tracks as electrodes for the studies of thin flakes by presenting the measurement of pressure-enhanced superconductivity and quantum oscillations in a flake of MoTe2.

9.
Sensors (Basel) ; 22(9)2022 May 04.
Article in English | MEDLINE | ID: mdl-35591180

ABSTRACT

The majority of digital sensors rely on von Neumann architecture microprocessors to process sampled data. When the sampled data require complex computation for 24×7, the processing element will a consume significant amount of energy and computation resources. Several new sensing algorithms use deep neural network algorithms and consume even more computation resources. High resource consumption prevents such systems for 24×7 deployment although they can deliver impressive results. This work adopts a Computing-In-Memory (CIM) device, which integrates a storage and analog processing unit to eliminate data movement, to process sampled data. This work designs and evaluates the CIM-based sensing framework for human pose recognition. The framework consists of uncertainty-aware training, activation function design, and CIM error model collection. The evaluation results show that the framework can improve the detection accuracy of three poses classification on CIM devices using binary weights from 33.3% to 91.5% while that on ideal CIM is 92.1%. Although on digital systems the accuracy is 98.7% with binary weight and 99.5% with floating weight, the energy consumption of executing 1 convolution layer on a CIM device is only 30,000 to 50,000 times less than the digital sensing system. Such a design can significantly reduce power consumption and enables battery-powered always-on sensors.


Subject(s)
Algorithms , Neural Networks, Computer , Humans
10.
Materials (Basel) ; 16(1)2022 Dec 22.
Article in English | MEDLINE | ID: mdl-36614442

ABSTRACT

In this study, wood samples extracted from the Taicang ancient ship, dating back to the Yuan Dynasty, were investigated to study the characteristics of waterlogged archaeological wood. The macroscopic characteristics and microscopic structures were used to identify the wood species. To assess the degree of degradation of the waterlogged archaeological wood, X-ray diffraction (XRD), nanoindentation (NI), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used to compare the new and ancient wood samples from the same species. The microscopic structures of the samples were identified as Pinus massoniana. The XRD and nanoindentation results revealed that the crystallinity index of the cellulose decreased from 41.07% to 33.85%, the elastic modulus was reduced by 20.90%, and hardness was reduced by 55.6% compared with the new wood. The FTIR spectra revealed that biological deterioration occurred in the cellulose and hemicellulose, but there was no noticeable change in the lignin content. These results provide helpful information for the conservation and restoration of ancient ships.

11.
Nano Lett ; 21(21): 9310-9317, 2021 Nov 10.
Article in English | MEDLINE | ID: mdl-34714653

ABSTRACT

The emergence of high transition temperature (Tc) superconductivity in bulk FeSe under pressure is associated with the tuning of nematicity and magnetism. However, sorting out the relative contributions from magnetic and nematic fluctuations to the enhancement of Tc remains challenging. Here, we design and conduct a series of high-pressure experiments on FeSe thin flakes. We find that as the thickness decreases the nematic phase boundary on temperature-pressure phase diagrams remains robust while the magnetic order is significantly weakened. A local maximum of Tc is observed outside the nematic phase region, not far from the extrapolated nematic end point in all samples. However, the maximum Tc value is reduced associated with the weakening of magnetism. No high-Tc phase is observed in the thinnest sample. Our results strongly suggest that nematic fluctuations alone can only have a limited effect while magnetic fluctuations are pivotal on the enhancement of Tc in FeSe.

12.
J Phys Condens Matter ; 34(6)2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34715684

ABSTRACT

Charge density wave (CDW) instability is often found in phase diagrams of superconductors such as cuprates and certain transition-metal dichalcogenides. This proximity to superconductivity triggers the question on whether CDW instability is responsible for the pairing of electrons in these superconductors. However, this issue remains unclear and new systems are desired to provide a better picture. Here, we report the temperature-pressure phase diagram of a recently discovered BiS2superconductor La2O2Bi3AgS6, which shows a possible CDW transition atT* ∼ 155 K and a superconducting transition atTc∼ 1.0 K at ambient pressure, via electrical resistivity measurements. Upon applying pressure,T* decreases linearly and extrapolates to 0 K at 3.9 GPa. Meanwhile,Tcis enhanced and reaches maximum value of 4.1 K at 3.1 GPa, forming a superconducting dome in the temperature-pressure phase diagram.

13.
Front Genet ; 12: 682503, 2021.
Article in English | MEDLINE | ID: mdl-34220957

ABSTRACT

BACKGROUND: CD39 is one of the functional surface markers for T regulatory cells, the prognostic role and immune-related effects of CD39 in luminal breast cancer (BC) patients has not been evaluated yet. The aim of the current study was to explore the association between CD39 expression and clinic pathological characteristics and the prognosis in luminal BC patients. METHODS: Clinical information and RNA-sequencing (RNA-Seq) expression data were extracted from The Cancer Genome Atlas (TCGA). Patients were divided into a high or low CD39 expression group by the optimal cutoff value (4.18) identified from the receiver operating characteristic curve analysis. The relationships between CD39 expression and clinic pathological features were evaluated by the corresponding statistical tests. Survival analyses were applied to evaluate the overall survival between the high and low CD39 expression groups in luminal BC. Furthermore, Gene Expression Omnibus datasets were used for external data validation. Gene set enrichment analysis (GSEA) was also performed, and CIBERSORT was used to analyze the immune cell populations. RESULTS: Analysis of 439 cases of tumor data showed that CD39 was overexpressed in luminal BC. The multivariable analysis suggested that CD39 expression was an independent prognostic factor for luminal BC patients. GSEA suggested that CD39 might play an important role in luminal BC progression through immune regulation. Analysis of immune cell patterns revealed high CD39 expression correlated to a higher proportion of CD8+ T cells and M2 macrophages. CONCLUSION: This study demonstrates that CD39 expression correlates with the prognosis of luminal BC through TCGA database mining. Further studies are warranted further to elucidate this potential novel therapeutic strategy for BC.

14.
Materials (Basel) ; 14(9)2021 May 06.
Article in English | MEDLINE | ID: mdl-34066532

ABSTRACT

Gold leaf samples of different purities were corroded in a SO2 atmosphere at three different relative humidities (30%, 60%, 90%) at ambient temperature, and the effects on color, gloss, and morphology were studied. Results showed that a corrosion rate of 0.0898 g/cm2 could be attained after 6 weeks at high humidity. Color changes also occurred during the gold leaf corrosion process, and many thin pits formed on the surfaces, as shown by SEM. EDX results showed that these pits contained C, O, and S compounds. By comparing the results of different gold purity samples and different relative humidity conditions, it could be concluded that both gold content and humidity play an important role in SO2 atmosphere corrosion. These conclusions are helpful for the conservation of gold leaf decorative cultural relics.

15.
Int J Nurs Stud ; 70: 27-37, 2017 May.
Article in English | MEDLINE | ID: mdl-28231440

ABSTRACT

BACKGROUND: Acupressure has been used as an effective way in treating with stomach upset. However the efficacy of acupressure in preventing chemotherapy-induced nausea and vomiting is uncertain. OBJECTIVE: To assess the effectiveness of acupressure on three categories of chemotherapy-induced nausea and vomiting. DATA SOURCES: Databases had been retrieved from inception through February 2016 for the randomized controlled trials in accordance with the inclusion criteria, including PubMed, Cochrane Central Register of Controlled Trials, Web of Science, EMBASE, Science Direct, CINAHL, China Biology Medicine, Chinese National Knowledge infrastructure, Wan Fang and Database for Chinese Technical Periodicals. Additional studies were identified through hand searches of bibliographies and Internet searches. DESIGN: Systematic review with meta-analyses and trial sequential analysis of randomized controlled trials. REVIEW METHODS: Two reviewers selected relevant eligible articles, critical appraisal of the methodological quality was conducted on the basis of using Cochrane Handbook. A standardized Excel form was used to extract information. Meta-analysis and trial sequential analysis was performed using software RevMan 5.3 and TSA 0.9. RESULTS: Twelve studies with 1419 patients were included. Only three studies were assessed as high quality, one study was evaluated as moderate, and eight studies were evaluated as poor. The meta-analysis showed that acupressure reduced the severity of acute (SMD=-0.18, 95% CI -0.31 to -0.05, p<0.01) and delayed (SMD=-0.33, 95% CI -0.64 to -0.01, p=0.04) nausea. However, there was no benefit effect on the incidence or frequency of vomiting. No definitive conclusions were drawn from the trial sequential analysis. CONCLUSION: This systematic review suggested a protective effect of acupressure on chemotherapy-induced nausea and vomiting, while more well-designed clinical trials with larger sample size were needed to draw a definitive conclusion.


Subject(s)
Acupressure , Antineoplastic Agents/adverse effects , Nausea/therapy , Vomiting/therapy , Humans , Nausea/chemically induced , Vomiting/chemically induced
16.
Sci Rep ; 5: 16125, 2015 Nov 04.
Article in English | MEDLINE | ID: mdl-26530454

ABSTRACT

In order to overcome drug resistant and enhance antitumor activity of DOX, a new pH-sensitive micelle (DOX/DQA-DOX@DSPE-hyd-PEG-AA) was prepared to simultaneously deliver DOX to nucleus and mitochondria. Drug released from DOX/DQA-DOX@DSPE-hyd-PEG-AA showed a pH-dependent manner. DOX/DQA-DOX@DSPE-hyd-PEG-AA induced the depolarization of mitochondria and apoptosis in MDA-MB-231/ADR cells and A549 cells, which resulted in the high cytotoxicity of DOX/DQA-DOX@DSPE-hyd-PEG-AA against MDA-MB-231/ADR cells and A549 cells. Confocal microscopy confirmed that DOX/DQA-DOX@DSPE-hyd-PEG-AA simultaneously delivered DQA-DOX and DOX to the mitochondria and nucleus of tumor cell. After DOX/DQA-DOX@DSPE-hyd-PEG-AA was injected to the tumor-bearing nude mice by the tail vein, DOX was mainly found in tumor tissue. But DOX was widely distributed in the whole body after the administration of free DOX. Compared with free DOX, the same dose of DOX/DQA-DOX@DSPE-hyd-PEG-AA significantly inhibited the growth of DOX-resistant tumor in tumor-bearing mice without obvious systemic toxicity. Therefore, dual subcellular compartment delivery of DOX greatly enhanced the antitumor activity of DOX on DOX-resistant tumor. DOX/DQA-DOX@DSPE-hyd-PEG-AA has the potential in target therapy for DOX-resistant tumor.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Apoptosis/drug effects , Doxorubicin/pharmacology , Drug Carriers/chemistry , Animals , Antibiotics, Antineoplastic/metabolism , Antibiotics, Antineoplastic/therapeutic use , Antibiotics, Antineoplastic/toxicity , Caspase 3/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Doxorubicin/metabolism , Doxorubicin/therapeutic use , Female , Humans , Hydrogen-Ion Concentration , Membrane Potential, Mitochondrial/drug effects , Mice , Mice, Inbred BALB C , Mice, Nude , Micelles , Neoplasms/drug therapy , Neoplasms/pathology , Phosphatidylethanolamines/chemistry , Polyethylene Glycols/chemistry , Tissue Distribution , Transplantation, Heterologous
17.
Biofactors ; 41(5): 352-9, 2015.
Article in English | MEDLINE | ID: mdl-26496994

ABSTRACT

Cytoskeletal reorganization is essential to keratinocyte function. Rac1 regulates cytoskeletal reorganization through signaling pathways such as the cofilin cascade. Cofilin severs actin filaments after activation by dephosphorylation. Rac1 was knocked out in mouse keratinocytes and it was found that actin filaments disassembled. In the epidermis of mice in which Rac1 was knocked out only in keratinocytes, cofilin phosphorylation was aberrantly elevated, corresponding to repression of the phosphatase slingshot1 (SSH1). These effects were independent of the signaling pathways for p21-activated kinase/LIM kinase (Pak/LIMK), protein kinase C, or protein kinase D or generation of reactive oxygen species. Similarly, when actin polymerization was specifically inhibited or Rac1 was knocked down, cofilin phosphorylation was enhanced and SSH1 was repressed. Repression of SSH1 partially blocked actin depolymerization induced by Rac1 depletion. Therefore, aberrant cofilin phosphorylation that induces actin polymerization might be a consequence of actin disassembly induced by the absence of Rac1.


Subject(s)
Actin Depolymerizing Factors/metabolism , Actins/metabolism , rac1 GTP-Binding Protein/metabolism , Actin Depolymerizing Factors/genetics , Animals , Cells, Cultured , Keratinocytes/metabolism , Mice , Phosphorylation , Reactive Oxygen Species/metabolism , Signal Transduction/genetics , Signal Transduction/physiology , rac1 GTP-Binding Protein/genetics
18.
J Ethnopharmacol ; 165: 243-50, 2015 May 13.
Article in English | MEDLINE | ID: mdl-25701755

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Glycyrrhizae radix et rhizoma (Gancao) is often prescribed together with Sophorae flavescentis radix (Kushen) in traditional Chinese medicinal practice to increase the efficacy on the treatment of hepatitis and hepatic fibrosis. Meanwhile, long-term single used Gancao can cause adverse reactions, lead to pseudohypercorticosteroidism especially. But the side effects of Gancao are significantly reduced when combined with Kushen; the reasons are still unknown. The aim of this study was to elucidate potential pharmacokinetic interaction between Kushen and Gancao, and to provide guidance for clinical medicine safety. MATERIALS AND METHODS: A specific and rapid HPLC-MS method was established to quantify the four main activity ingredients matrine (MT), oxymatrine (OMT), glycyrrhizin (GL) and glycyrrhetinic acid (GA) in rat plasma. In this study, the pharmacokinetic parameters and the pharmacokinetic differences of the four main activity ingredients MT, OMT, GL and GA in single herb and Kushen-Gancao couple were obtained. RESULTS: Compared with oral administration of Gancao extract, K10 and Tmax of GA significantly increased to 0.43 h(-1)and 30 h after giving Kushen-Gancao (p < 0.05), but T1/2 and Vd were reduced to 0.73 L kg(-1)and 4.98 h (p < 0.05). In addition, the AUC of GA was increased, and the other three activity ingredients all decreased. CONCLUSION: GA as the main factor leading to the sodium-water retention side effects of Gancao. The result found that the absorption of GA was significantly slowed down and the metabolism rate was accelerated in Kushen-Gancao than single herb. So the attenuated toxicity mechanism may be because the accumulation of GA reduced in vivo. The conclusion has important meaning to the compatibility of Chinese med.


Subject(s)
Drugs, Chinese Herbal/toxicity , Glycyrrhiza , Sophora , Animals , Chromatography, High Pressure Liquid , Drug Interactions , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/pharmacokinetics , Glycyrrhiza/chemistry , Male , Mass Spectrometry , Rats , Rats, Sprague-Dawley , Sophora/chemistry
19.
Asian Pac J Cancer Prev ; 15(22): 9699-706, 2014.
Article in English | MEDLINE | ID: mdl-25520091

ABSTRACT

BACKGROUND: The predictive value of the xeroderma pigmentosum group D (XPD) Lys751Gln polymorphism regarding clinical outcomes of patients with colorectal cancer (CRC) receiving oxaliplatin-based chemotherapy has been evaluated in numerous published studies, but the results remain inconclusive. Therefore, we performed a meta-analysis to determine the precise role of the XPD Lys751Gln polymorphism in this clinical situation and optimize individual chemotherapy. MATERIALS AND METHODS: A multiple search strategy was used to identify eligible studies. Pooled odds ratios (ORs), generalized odds ratio (ORG) and their 95% confidence intervals (CIs) were used to estimate the objective response, while hazard ratios (HRs) with 95%CIs were used for progression-free survival (PFS) and overall survival (OS). RESULTS: A total of 17 studies including 2,286 patients met the inclusion criteria. Overall, the XPD 751Gln allele was associated with a non-significant reduced objective response to oxaliplatin-based chemotherapy in all patients or in the Asian and Caucasian subgroups. However, poor PFS and OS of CRC patients treated with oxaliplatin-based regimens were significantly related to the XPD 751Gln allele in the dominant model (PFS: HR=2.10, 95%CI: 1.65-2.67; OS: HR=3.18, 95%CI: 1.57-6.47). On stratified analysis by ethnicity, these relationships were more pronounced in Asians (PFS: HR=2.49, 95%CI: 1.79-3.47; OS: HR=5.25, 95%CI: 3.46-7.94) than in Caucasians (PFS: HR=1.73, 95%CI: 1.22-2.46; OS: HR=1.78, 95%CI: 1.06-2.99). CONCLUSIONS: The XPD Lys751Gln polymorphism may have prognostic value in patients with CRC undergoing oxaliplatin-based chemotherapy.


Subject(s)
Antineoplastic Agents/therapeutic use , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Organoplatinum Compounds/therapeutic use , Polymorphism, Genetic/genetics , Xeroderma Pigmentosum Group D Protein/genetics , Humans , Oxaliplatin , Prognosis , Risk Factors
20.
Asian Pac J Cancer Prev ; 15(19): 8383-90, 2014.
Article in English | MEDLINE | ID: mdl-25339033

ABSTRACT

BACKGROUND: Although the predictive value of the excision repair cross-complementing group 1 (ERCC1) C118T polymorphism in clinical outcomes of patients with colorectal cancer (CRC) receiving oxaliplatin-based chemotherapy has been evaluated in numerous published studies, the conclusions are conflicting. Therefore, we performed the present meta-analysis to determine the precise role of the ERCC1 C118T polymorphism in this clinical situation and help optimize individual chemotherapy. MATERIALS AND METHODS: A multiple search strategy was used to identify eligible studies. Pooled odds ratios (ORs) and their 95% confidence intervals (CIs) were used to estimate objective response and oxaliplatin-induced toxicity, with hazard ratios (HRs) with 95%CIs for progression-free survival (PFS) and overall survival (OS). RESULTS: A total of 22 studies including 2,846 CRC patients were eligible in the analysis. Overall, no significant correlation was found between the ERCC1 C118T polymorphism and objective response to oxaliplatin-based chemotherapy, in all patients or in the Asian and Caucasian subgroups. However, the pooled analysis showed that the PFS and OS were significantly shorter in patients who carried T/T or T/C genotypes of ERCC1 C118T as compared to the C/C genotype. On stratified analysis by ethnicity, the ERCC1 118T allele was associated with a favorable prognosis in Caucasians (PFS, HR=0.58, 95%CI: 0.24-1.44; OS, HR=0.38, 95%CI: 0.22-0.64) but an unfavorable prognosis in Asians (PFS, HR=2.49, 95%CI: 1.87-3.33; OS, HR=2.63, 95%CI: 1.87-3.69) based on a dominant model. In addition, we failed to find a statistically significant impact of ERCC1 C118T polymorphism on oxaliplatin-induced toxicity. CONCLUSIONS: The ERCC1 C118T polymorphism may have prognostic value in patients with CRC undergoing oxaliplatin-based chemotherapy.


Subject(s)
Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , DNA-Binding Proteins/genetics , Endonucleases/genetics , Organoplatinum Compounds/therapeutic use , Polymorphism, Genetic/genetics , Antineoplastic Agents/therapeutic use , Colorectal Neoplasms/mortality , Humans , Oxaliplatin , Prognosis , Risk Factors , Survival Rate
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