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1.
Phys Chem Chem Phys ; 26(4): 3110-3116, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38189422

RESUMO

Based on first-principles calculations, we predict a class of graphene-like magnetic materials, transition metal carbonitrides MN4C6 (M = Cr, Mn, Fe, and Co), which are made up of a benzene ring and an MN4 moiety, two common planar units in the compounds. The structural stability is demonstrated by the phonon and molecular dynamics calculations, and the formation mechanism of the planar geometry of MN4C6 is ascribed to the synergistic effect of sp2 hybridization, M-N coordination bond, and π-d conjugation. The MN4C6 materials consist of only one layer of atoms and the transition metal atom is located in the planar crystal field, which is markedly different from most two-dimensional materials. The calculations indicate that MnN4C6, FeN4C6, and CoN4C6 are ferromagnetic while CrN4C6 has an antiferromagnetic ground state. The Curie temperatures are estimated by solving the anisotropic Heisenberg model with the Monte Carlo method.

2.
Molecules ; 29(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38792183

RESUMO

Two-dimensional intrinsic magnetic materials with high Curie temperature are promising candidates for next-generation spintronic devices. In this work, we design two kinds of two-dimensional transition metal nitrides, VN2 and FeN2, both with a hexagonal honeycomb lattice. Based on the formation energy, and phonon spectra calculations as well as the molecular dynamics simulations, their structural stability is demonstrated. Then, we determine the ferromagnetic ground states of VN2 and FeN2 monolayers through the energy calculations, and the Curie temperatures of 222 K and 238 K are estimated by solving the Heisenberg model using the Monte Carlo simulation method. Hence, the VN2 and FeN2 monolayers are demonstrated to be new two-dimensional ferromagnetic materials with high temperature ferromagnetism or large-gap half-metallicity.

3.
Phys Chem Chem Phys ; 25(30): 20189-20193, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37489584

RESUMO

Transition metal single-atom catalysts have attracted great attention because of their great potential applications in the chemical industry. Except for graphene, there are few single-layer materials that can act as substrates to support the dispersive metal atoms. Recently, a biphenylene layer, a new two-dimensional allotrope of graphene, was synthesized in experiments, providing a new substrate layer to fabricate single-atom catalysts (SACs). In this work, we predict three transition metal SACs MN4-biphenylene (M = Fe, Co, and Ni) based on first-principles calculations. The results indicate that FeN4-biphenylene is a promising bifunctional catalyst with low overpotentials for both the oxygen reduction reaction and oxygen evolution reaction, ηORR = 0.11 V and ηOER = 0.27 V. The high catalytic activities are explained by the position of the d-band center of the Fe atom in the biphenylene network and the strength of interaction between FeN4-biphenylene and the reaction intermediates.

4.
J Chem Phys ; 150(7): 074306, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795678

RESUMO

To clarify the charge transfer effect on Raman spectra of aromatic hydrocarbons, we investigate the Raman shifts of phenanthrene, p-terphenyl, and anthracene and their negatively charged counterparts by using density functional theory. For the three molecules, upon charge increasing, the computed Raman peaks generally shift down with the exception of a few shifting up. The characteristic Raman modes in the 0-1000 cm-1 region persist up, while some high-frequency ones change dramatically with three charges transferred. The calculated Raman shifts for one- and two-electron transfer are in agreement with the measured Raman spectra, and in accordance to the stoichiometric ratios 1:1 and 2:1 of the metal atom and aromatic hydrocarbon molecule in recent experimental and theoretical studies. Our theoretical results provide the fundamental information to elucidate the Raman shifts and the stoichiometric ratios for alkali-metal-doped aromatic hydrocarbons.

5.
J Chem Phys ; 141(22): 224501, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25494754

RESUMO

We have systematically investigated the crystal structure of Ba-doped phenanthrene with various Ba doping levels by the first-principles calculations combined with the X-ray diffraction (XRD) spectra simulations. Although the experimental stoichiometry ratio of Ba atom and phenanthrene molecule is 1.5:1, the simulated XRD spectra, space group symmetry and optimized lattice parameters of Ba1.5phenanthrene are not consistent with the experimental ones, while the results for Ba2phenanthrene are in good agreement with the measurements. The strength difference of a few XRD peaks can be explained by the existence of pristine phenanthrene. Our findings suggest that instead of uniform Ba1.5phenanthrene, there coexist Ba2phenanthrene and undoped phenanthrene in the superconducting sample. The electronic calculations indicate that Ba2phenanthrene is a semiconductor with a small energy gap less than 0.05 eV.

6.
J Chem Phys ; 139(20): 204709, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24289371

RESUMO

By the first principle calculations based on the van der Waals density functional theory, we study the crystal structures and electronic properties of La-doped phenanthrene. Two stable atomic geometries of La1phenanthrene are obtained by relaxation of atomic positions from various initial structures. The structure-I is a metal with two energy bands crossing the Fermi level, while the structure-II displays a semiconducting state with an energy gap of 0.15 eV, which has an energy gain of 0.42 eV per unit cell compared to the structure-I. The most striking feature of La1phenanthrene is that La 5d electrons make a significant contribution to the total density of state around the Fermi level, which is distinct from potassium doped phenanthrene and picene. Our findings provide an important foundation for the understanding of superconductivity in La-doped phenanthrene.

7.
Nanoscale ; 14(38): 14191-14198, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36125028

RESUMO

Using first-principles calculations, we predict a stable two-dimensional atomically thin material MgN4. This material has a perfect intrinsic electron-hole compensation characteristic with high carrier mobility, making it a promising candidate material with extremely large magnetoresistance. As the magnetic field increases, the magnetoresistance of the monolayer MgN4 will show a quadratic dependence on the strength of the magnetic field without saturation. Furthermore, nontrivial topological properties are also found in this material. In the absence of spin-orbit coupling, the monolayer MgN4 belongs to a topological nodal-line material, in which the band crossings form a closed saddle-shape nodal-ring near the Fermi level in the Brillouin zone. Once the spin-orbit coupling is considered, a small local energy gap is opened along the nodal ring, resulting in a topological insulator defined on a curved Fermi surface with 2 = 1. The combination of two-dimensional single-atomic-layer thickness, an extremely large magnetoresistance effect, and topological non-trivial properties in the monolayer MgN4 makes it an excellent platform for designing novel multi-functional devices.

8.
ACS Omega ; 7(47): 43316-43320, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36467953

RESUMO

The MnSn monolayer synthesized recently is a novel two-dimensional ferromagnetic material with a hexagonal lattice, in which three Mn atoms come together to form a trimer, making it remarkably different from other magnetic two-dimensional materials. Most impressively, there occurs a sharp increase of the Curie temperature from 54 to 225 K when the number of layers increases from 1 to 3. However, no quantitative explanation has been reported in previous studies. Herein, by means of the first-principles calculation method and the Monte Carlo method, we demonstrate that strong interlayer ferromagnetic coupling plays an essential role in enhancing its critical temperature, which acts as a magnetic field to stabilize the ferromagnetism in MnSn multilayers. Our work not only explains the sharp increase of the Curie temperature of the MnSn film in experiments but also reveals that the interlayer coupling is a new routine to achieve high-temperature ferromagnetism in two-dimensional materials.

9.
Phys Rev Lett ; 106(8): 087005, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21405594

RESUMO

By the first-principles electronic structure calculations, we find that the ground state of the Fe-vacancies ordered TlFe(1.5)Se(2) is a quasi-two-dimensional collinear antiferromagnetic semiconductor with an energy gap of 94 meV, in agreement with experimental measurements. This antiferromagnetic order is driven by the Se-bridged antiferromagnetic superexchange interactions between Fe moments. Similarly, we find that crystals AFe(1.5)Se(2) (A=K, Rb, or Cs) are also antiferromagnetic semiconductors but with a zero-gap semiconducting state or semimetallic state nearly degenerated with the ground states. Thus, rich physical properties and phase diagrams are expected.

10.
Prep Biochem Biotechnol ; 39(2): 208-17, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19291583

RESUMO

Recently, it was found that Aquaporin 1 (AQP1) is expressed strongly in proliferating microvessels, but the role of AQP1 in retinal neovascularization remains unknown. Here, we report the distribution of AQP1 expression during neovascularization of the retina in a mouse model of retinopathy of prematurity. AQP1 was expressed in all of the samples examined in P15 mouse and P17 mouse, including experimental and control groups. Immunostaining results showed that AQP1 is located in microvessel endothelia in retinas with proliferative retinopathy and prominently in the outer retina. Expression of AQP1 was significantly increased in experimental animals at P17, compared with control mice. No significant difference was seen in the levels of AQP1 on P12 or P15, compared with control mice. These results suggest that AQP1 may play an important role in retinal neovascularization.


Assuntos
Aquaporina 1/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Neovascularização Retiniana/genética , Retinopatia da Prematuridade/metabolismo , Animais , Animais Recém-Nascidos , Aquaporina 1/biossíntese , Aquaporina 1/metabolismo , Western Blotting , Humanos , Recém-Nascido , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Journal of Medical Research ; (12): 121-125, 2024.
Artigo em Chinês | WPRIM | ID: wpr-1023609

RESUMO

Objective To investigate the expression level and clinical significance of serum long noncoding RNA(lncRNA)H19,CHAST in patients with coronary heart disease(CHD).Methods A total of 135 patients with CHD who were admitted to the Department of Cardiovascular Medicine of Lianyungang Second People's Hospital from June 2021 to May 2022 were selected,including 76 cases of a-cute coronary syndrome and 59 cases of chronic coronary syndrome.We selected 62 patients in the control group who were hospitalized and excluded from CHD by coronary angiography.Real-time fluorescent quantitative PCR(RT-PCR)was used to detect the relative expres-sion level of lncRNA H19 and lncRNA CHAST in the circulating serum of the subjects.Meanwhile,the high sensitivity C-reactive pro-tein(hs-CRP)、tumor necrosis factor-α(TNF-α)、interleukin-6(IL-6)、low density lipoprotein(LDL)、high density lipoprotein(HDL)and other related indicators of each group were collected.The receiver operating characteristic(ROC)curve was used to analyze the clinical diagnostic value of circulating serum lncRNA H19 and lncRNA CHAST expression level in the diagnosis of CHD.Pearson cor-relation coefficient was used to analyze the correlation between serum lncRNA H19,lncRNA CHAST level,and other related indicators.Multivariate Logistic regression was used to analyze the risk factors of CHD.Results The serum expression levels of lncRNA H19 and ln-cRNA CHAST in the CHD group were higher than those in the control group(P<0.05).The serum levels of hs-CRP、TNF-α、IL-6、and LDL in the experimental group were higher than those in the control group(P<0.05),and the serum levels of HDL were lower than those in the control group(P<0.05).The expression levels of lncRNA H19 and lncRNA CHAST were positively correlated with hs-CRP,IL-6 and LDL,and were negatively correlated with HDL.lncRNA H19 and lncRNA CHAST are risk factors for CHD,which may have a higher value in the diagnosis of CHD.Conclusion lncRNA H19 and lncRNA CHAST are risk factors for CHD and can be used as serum indicators for the diagnosis of CHD,and the combination of the two has a higher value in the diagnosis of CHD.In addition,the ex-pression levels of both were correlated with the levels of inflammatory factors and apolipoproteins.

12.
Artigo em Chinês | WPRIM | ID: wpr-1024454

RESUMO

Objective To explore the value of ultrasonic quantitative measurement of hepatorenal index(HRI)for diagnosing non-alcoholic fatty liver disease(NAFLD)in children.Methods Abdominal ultrasound and upper abdominal MRI data of 70 obese children were retrospectively analyzed.ROI with different sizes and shapes of liver and right kidney were delineated on longitudinal and transverse ultrasound images,respectively,and the echo intensity of ROIs were measured to obtain HRIsmall ROI on longitudinal section,HRIsmall ROI on transverse section,HRIlarge ROI on longitudinal section and HRIlarge ROI on transverse section,i.e.HRI1,HRI2,HRI3,HRI4,while the gray,skewness and kurtosis of liver ultrasound image were recorded.Liver proton density fat fraction(PDFF)were measured based on MRI,and NAFLD was diagnoses taken PDFF≥6%as standard.The correlations of HRI with PDFF and liver ultrasound image related parameters were analyzed.Taken MRI as the standard,receiver operating characteristic(ROC)curve was drawn to evaluate the diagnostic efficacy of HRI for NAFLD.Multivariate logistic regression analysis was performed taken age,sex,body mass index(BMI)percentile,HRI3 and liver ultrasound image related parameters as independent variables and MRI diagnosis of NAFLD as dependent variable to screen the predictors of MRI diagnosis of NAFLD.Results HRI1,HRI2,HRI3 and HRI4 obtained with ultrasound was 1.89±0.52,1.88±0.55,1.97±0.51 and 1.92±0.55,respectively.PDFF obtained with MRI was(12.53±3.14)%,and diagnosed NAFLD in 34 cases.HRI and PDFF had moderate positive correlation(r=0.51-0.61,all P<0.01).The correlation between HRI3 and PDFF was the strongest(r=0.61),and HRI3 was weakly correlated with liver gray3(r=-0.270,P=0.020),with area under the curve(AUC)for diagnosing NAFLD of 0.93(P<0.01).BMI percentile(OR=1.06),HRI3(OR=34.20)and liver gray3(OR=0.79)were all predictive factors for MRI diagnosis of NAFLD.Conclusion Ultrasonic quantitative measurement of HRI had high clinical value for diagnosing NAFLD in children.

13.
Artigo em Chinês | WPRIM | ID: wpr-1027907

RESUMO

Objective:To investigate the value of traditional metabolic parameters, CT features and intratumoral heterogeneity parameters measured by 18F-FDG PET/CT in predicting the mutation status of the epidermal growth factor receptor (EGFR) gene in patients with adenocarcinoma. Methods:A total of 147 patients (73 males, 74 females, age (59.8±10.2) years) with pathological confirmed adenocarcinoma between January 2016 and June 2020 in the Affiliated Hospital of Jining Medical University were retrospectively included. The differences of clinical data (smoking history, tumor location and clinical stage), CT features (maximum diameter, ground-glass opacity content, lobulation, speculation, cavitation, air-bronchogram, pleural retraction and bronchial cut-off sign), 18F-FDG PET/CT traditional metabolic parameters (SUV max, SUV mean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG)) and intratumoral heterogeneity parameters ( CV, heterogeneity index (HI)) were analyzed between patients with EGFR mutation and patients with EGFR wild-type. Independent-sample t test, Mann-Whitney U test and χ2 test were used to analyze the data. Multivariate logistic regression was used to analyze the predictors of EGFR mutation. ROC curve analysis was used to evaluate the predictive value of clinical and PET/CT information. Results:Among 147 patients, 87 were with EGFR mutation and 60 were with EGFR wild-type. There were significant differences in gender (male/female), smoking history (with/without), location (peripheral lesion/central lesion), pleural retraction (with/without), SUV max, SUV mean, TLG, CV and HI ( χ2 values: 4.72-23.89, z values: from -2.31 to 5.74, all P<0.05). Multivariate logistic regression analysis showed that smoking history (odds ratio ( OR)=0.167, 95% CI: 0.076-0.366; P<0.001), pleural retraction ( OR=1.404, 95% CI: 1.115-3.745; P=0.012), SUV max ( OR=0.922, 95% CI: 0.855-0.995; P=0.003), TLG ( OR=0.991, 95% CI: 0.986-0.996; P=0.001) and HI ( OR=0.796, 95% CI: 0.700-0.859; P<0.001) were predictors of EGFR mutation. ROC curve analysis showed the AUC of HI was 0.779, with the sensitivity of 76.67%(46/60) and the specificity of 79.31%(69/87). The predictive model was constructed by combining smoking history, pleural retraction, TLG, SUV max and HI, and the AUC was 0.908, with the sensitivity of 88.33%(53/60) and the specificity of 68.97%(60/87). The difference of AUCs between HI and the predictive model was statistically significant ( z=3.71, P<0.001). Conclusion:HI can predict EGFR mutations better, and the predictive value for EGFR mutations can be enhanced when combining HI with smoking history, pleural retraction, TLG and SUV max.

14.
Artigo em Chinês | WPRIM | ID: wpr-1027409

RESUMO

Objective:To investigate the value of radiomics nomogram based on standardized pre-treatment chest enhanced CT in predicting the mutation status of epidermal growth factor receptor (EGFR) for patients with lung adenocarcinoma.Methods:A retrospective analysis was conducted on pre-treatment chest enhanced CT images and clinical data of 262 patients from the affiliated hospital of Jining Medical University with pathologically proven primary lung adenocarcinoma who received EGFR gene testing, including EGFR wild type ( n=122) and mutant type ( n=140). The patients were divided into training group ( n=183) and testing group ( n=79) according to a ratio of 7∶3 by stratified sampling method. Standardized pre-processed the images, delineated the ROI and extracted the radiomics features. Least absolute shrinkage and selection operator (LASSO) algorithm was used to reduce the dimension and select key features. The standardized radiomics model, clinical model and the combined model were established by Logistic Regression (LR) machine learning method. Calculated the Rad-score and drew the nomogram. ROC curve and Delong were used to evaluate and compare the predictive performance of different models. Results:23 standardized enhanced CT radiomics features and 4 clinical features were selected. The predictive performance of standardized radiomics model was better than that of non-standardized radiomics model [area under curve (AUC): 0.863 vs. 0.805, t=2.19, P<0.05]. The AUCs of the combined model and standardized radiomics model were higher than that of the clinical model (training group: 0.885, 0.863 vs. 0.774, t=3.57, 2.17, P<0.05; testing group: 0.873, 0.829 vs. 0.763, t=2.19, 2.02, P<0.05). The radiomics nomogram was built based on Rad-score, age, sex, smoking history and BMI. Conclusions:The combined model and standardized radiomics model could effectively predict the mutation status of EGFR gene in lung adenocarcinoma patients before treatment, providing valuable clinical insights.

15.
Artigo em Chinês | WPRIM | ID: wpr-1018440

RESUMO

Objective To observe the clinical efficacy of acupuncture at Neiyingxiang(EX-HN09)points combined with western medicine in the treatment of allergic rhinitis of deficiency-cold of lung qi type.Methods Sixty patients with deficiency-cold of lung qi type of allergic rhinitis were randomly divided into observation group and control group,with 30 patients in each group.The control group was treated with Desloratadine Tablets combined with Mometasone Furoate Aqueous Nasal Spray,and the observation group was treated with acupuncture at Neiyingxiang points combined with the self-made rhinitis recipe on the basis of the control group,and the clinical efficacy of the two groups was evaluated after 14 days.The changes of nasal symptom scores,Visual Analogue Scale(VAS)and rhinoconjunctivitis quality of life scores of the patients of the two groups were observed before and after the treatment.After 14 days of treatment,the clinical efficacy of the two groups was evaluated.The changes in nasal symptom scores,as well as VAS and rhinoconjunctivitis quality of life questionnaire(RQLQ)scores were observed before and after treatment.The changes in traditional Chinese medicine(TCM)sydnrome scores and serum immunoglobulin E(IgE)were compared before and after treatment in the two groups,and the safety of the two groups was evaluated.Results(1)The total effective rate of the observation group was 93.33%(28/30),and the control group was 73.33%(22/30).The efficacy of the observation group was superior to that of the control group,and the difference was statistically significant(P<0.05).(2)After treatment,the symptoms of nasal congestion,sneezing,runny nose and nasal itching were significantly improved in the two groups(P<0.01),and the observation group was significantly superior to the control group in improving nasal symptoms,and the differences were statistically significant(P<0.05).(3)After treatment,the VAS scores of patients in the two groups were significantly improved(P<0.01),and the observation group was superior to the control group in improving VAS scores,with statistically significant differences(P<0.05).(4)After treatment,the PQLQ scores of patients in the two groups improved significantly(P<0.01),and the observation group was significantly superior to the control group in improving the PQLQ scores,and the difference was statistically significant(P<0.05).(5)After treatment,the TCM syndrome scores of the patients in the two groups were significantly improved(P<0.01),and the observation group was significantly superior to the control group in improving TCM syndrome scores,with statistically significant differences(P<0.05).(6)After treatment,the serum IgE levels of patients in the two groups were significantly improved(P<0.01),and the observation group was significantly superior to the control group in improving serum IgE levels(P<0.05),with a statistically significant difference.(7)There was no significant difference in the incidence of adverse reactions between the observation group and the control group(P>0.05).Conclusion Acupuncture at Neiyingxiang points plus self-made rhinitis recipe combined with western medicine in the treatment of deficiency-cold of lung qi type of allergic rhinitis can significantly improve the clinical symptoms of the patients,thus improving the quality of life of the patients,and the therapeutic efficacy is remarkable.

16.
Artigo em Chinês | WPRIM | ID: wpr-1019127

RESUMO

Objective To compare seminal carnitine levels between normal males and asthenozoospermic patients,evaluate its correla-tion with progressive motility(PR)of sperm,and observe the effects of exogenous carnitine supplementation on asthenozoospermic pa-tients.Methods Semen samples were collected from 511 normal fertile males and asthenozoospermic patients.Seminal was measured using a fixed-time assay kit and the levels of carnitine were compared between the two groups.The consistency between seminal carni-tine and PR was assessed.Additionally,77 asthenozoospermic patients received L-carnitine(1 g/time,3 times/day,30 days/course).The levels of seminal carnitine and PR alteration pre-and post-treatment were monitored.Results The seminal L-carnitine level in the patients with asthenospermia([194.34±65.41]μmol/L)was significantly lower than that in normal fertile males([405.43±72.12]μmol/L)(P<0.01).When the seminal L-carnitine level ≥325 μmol/L was set as the threshold,the statistical results showed that Kappa value was 0.81,with a diagnostic coincidence rate of 93.74%.After one course of administration of L-carnitine,the concentra-tion of seminal L-carnitine([356.03±84.87]μmol/L)and PR([32.69±8.35]%)were significantly higher those that before treat-ment([183.61±79.54]μmol/L and[16.56±7.74]%,P<0.01).Conclusion The seminal carnitine assay kit could be used for ac-curate and high-throughput quantification of clinical samples,facilitating asthenozoospermia diagnosis and therapeutic efficacy evalua-tion.Exogenous carnitine supplementation may elevate seminal carnitine levels and sperm motility in asthenozoospermic patients and po-tentially improve their fertility.

17.
Artigo em Chinês | WPRIM | ID: wpr-1015622

RESUMO

Myocardial infarction(MI), an acute coronary syndrome that poses a serious risk to human health, involves multiple pathophysiological processes, including calcium overload. Existing therapeutic approaches and preventive measures have limitations and cannot effectively repair myocardial cells with poor regenerative potential. Exploring multiple programmed modes of cardiomyocyte death could help find potential targets for the treatment of myocardial infarction, and the potential role of ferroptosis as a novel mode of cell death in myocardial infarction has attracted great attention. The aim of this study was to investigate whether Ca

18.
Artigo em Inglês | WPRIM | ID: wpr-971472

RESUMO

Carotenoids are secondary metabolite responsible for colored pigments in plants and microbes (Li et al., 2022). They are a class of C40 tetraterpenoids consisting of eight isoprenoid units, and can be classified into carotenes and xanthophylls on the basis of their functional groups (Saini et al., 2015). Carotenes can be linear (phytoene, phytofluene, and ζ‍-carotene) or branched (β‍-carotene and α‍-carotene). Xanthophylls comprise β,β‍-xanthophylls (β‍-cryptoxanthin, zeaxanthin, violaxanthins, and neoxanthin) and β,ε‍-xanthophylls (α-cryptoxanthin, α-carotene, and lutein). Citrus fruits are complex sources of carotenoids, which are the principal pigments responsible for the typical orange color of most types (Chen, 2020). The difference in total carotenoid content and the diversity of carotenoid isomer proportion also accounts for other colors of citrus fruits, such as yellow, red, and pink (Chen, 2020).


Assuntos
Citrus/metabolismo , Carotenoides , Xantofilas , Luteína/metabolismo , Zeaxantinas/metabolismo , Frutas
19.
Acta Pharmaceutica Sinica B ; (6): 227-245, 2023.
Artigo em Inglês | WPRIM | ID: wpr-971707

RESUMO

Body is equipped with organic cation transporters (OCTs). These OCTs mediate drug transport and are also involved in some disease process. We aimed to investigate whether liver failure alters intestinal, hepatic and renal Oct expressions using bile duct ligation (BDL) rats. Pharmacokinetic analysis demonstrates that BDL decreases plasma metformin exposure, associated with decreased intestinal absorption and increased urinary excretion. Western blot shows that BDL significantly downregulates intestinal Oct2 and hepatic Oct1 but upregulates renal and hepatic Oct2. In vitro cell experiments show that chenodeoxycholic acid (CDCA), bilirubin and farnesoid X receptor (FXR) agonist GW4064 increase OCT2/Oct2 but decrease OCT1/Oct1, which are remarkably attenuated by glycine-β-muricholic acid and silencing FXR. Significantly lowered intestinal CDCA and increased plasma bilirubin levels contribute to different Octs regulation by BDL, which are confirmed using CDCA-treated and bilirubin-treated rats. A disease-based physiologically based pharmacokinetic model characterizing intestinal, hepatic and renal Octs was successfully developed to predict metformin pharmacokinetics in rats. In conclusion, BDL remarkably downregulates expressions of intestinal Oct2 and hepatic Oct1 protein while upregulates expressions of renal and hepatic Oct2 protein in rats, finally, decreasing plasma exposure and impairing hypoglycemic effects of metformin. BDL differently regulates Oct expressions via Fxr activation by CDCA and bilirubin.

20.
Artigo em Chinês | WPRIM | ID: wpr-972290

RESUMO

ObjectiveTo explore the mechanism of Dendrobium huoshanense polysaccharide (DHP) against inflammatory damage of neurons in Parkinson's disease (PD) model. MethodSH-SY5Y cells were randomized into blank group, model group, and DHP group. The survival rate of cells was measured by thiazole blue(MTT) assay, and the levels of lactate dehydrogenase (LDH), reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) were measured by colorimetric analysis. BV-2 microglia were classified into blank group, model group, DHP group, and MCC950 group (positive control group), and enzyme-linked immunosorbent assay (ELISA) was applied to detect the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-18 (IL-18). The expression of NOD-like receptor protein 3 (NLRP3), adaptor protein apoptosis-associated dot protein (ASC), cysteine aspartic protease-1 (Caspase-1), and IL-1β was measured by Western blot. A total of 50 C57BL/6 mice were randomized into blank group, model group, DHP low-dose (100 mg·kg-1) group, DHP equivalent-dose (350 mg·kg-1) group, and MCC950 group (positive control group), 10 mice in each group. The motor balance and coordination of C57BL/6 mice were observed by beam walking test, tail suspension test and rotarod test. The levels of Iba-1 and tyrosine hydroxylase (TH) were detected by immunofluorescence staining. The damage of dopaminergic neurons in the substantia nigra was detected by FJB staining. The levels of inflammatory factors such as IL-1β, IL-18, and TNF-α in mouse midbrain tissues were detected by ELISA and the protein levels of NLRP3, ASC, Caspase-1, and IL-1β protein were measured by Western blot. ResultCompared with the blank group, the SH-SY5Y model group showed decreased cell survival, increased levels of LDH, ROS, and MDA (P<0.05), and decreased levels of SOD (P<0.05). Compared with the model group, the DHP group demonstrated increased cell survival, decreased levels of LDH, ROS, and MDA (P<0.01), and increased level of SOD (P<0.01). Compared with the blank group, BV-2 model group had high levels of IL-1β, IL-18, and TNF-α (P<0.05) and high protein expression of NLRP3, Caspase-1, IL-1β, and ASC (P<0.05). Compared with the model group, DHP and MCC950 groups demonstrated low levels of IL-1β, IL-18, and TNF-α (P<0.01) and low protein expression of NLRP3, Caspase-1, IL-1β, and ASC (P<0.01). Compared with the blank group, the C57BL/6 model group displayed long time to pass the balance wood (P<0.05), short time spent on the rod in the rotarod test (P<0.05), high levels of IL-1β, IL-18, and TNF-α (P<0.05) and expression of Iba-1 in the midbrain substantia nigra (P<0.05), low TH expression (P<0.05), more positive neurons in the FJB staining (P<0.05), and high expression of NLRP3, Caspase-1, ASC, and IL-1β proteins (P < 0.05). Compared with the model group, the mice in the DHP and MCC950 groups had short time to pass the balance beam (P<0.01), long time spent on the rod (P<0.01), low levels of IL-1β, IL-18, and TNF-α (P<0.01), low Iba-1 expression in midbrain substantia nigra (P<0.01), high TH expression (P<0.01), and small number of positive neurons in the midbrain substantia nigra (P<0.01). The expression of NLRP3, ASC, and IL-1β proteins was lower in the MCC950 group (P<0.01), and the expression of NLRP3, ASC, Caspase-1 and IL-1β proteins was lower in the DHP equivalent-dose group (P<0.01) than in the model group. ConclusionDHP has anti-oxidative stress effect. It regulates the expression of NLRP3 inflammasome and inhibits the overactivation of microglia, thereby alleviating the neuroinflammatory injury in PD and exerting the neuroprotective effect.

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