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1.
Proc Natl Acad Sci U S A ; 120(11): e2217816120, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36897971

RESUMO

Superconductivity is a macroscopic manifestation of a quantum phenomenon where pairs of electrons delocalize and develop phase coherence over a long distance. A long-standing quest has been to address the underlying microscopic mechanisms that fundamentally limit the superconducting transition temperature, Tc. A platform which serves as an ideal playground for realizing "high"-temperature superconductors are materials where the electrons' kinetic energy is quenched and interactions provide the only energy scale in the problem. However, when the noninteracting bandwidth for a set of isolated bands is small compared to the interactions, the problem is inherently nonperturbative. In two spatial dimensions, Tc is controlled by superconducting phase stiffness. Here, we present a theoretical framework for computing the electromagnetic response for generic model Hamiltonians, which controls the maximum possible superconducting phase stiffness and thereby Tc, without resorting to any mean-field approximation. Our explicit computations demonstrate that the contribution to the phase stiffness arises from i) "integrating out" the remote bands that couple to the microscopic current operator and ii) the density-density interactions projected on to the isolated narrow bands. Our framework can be used to obtain an upper bound on the phase stiffness and relatedly Tc for a range of physically inspired models involving both topological and nontopological narrow bands with density-density interactions. We discuss a number of salient aspects of this formalism by applying it to a specific model of interacting flat bands and compare the upper bound against the known Tc from independent numerically exact computations.

2.
J Relig Health ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789716

RESUMO

China has over 100 million people living with type 2 diabetes mellitus (T2DM). Interventions framed around pre-existing personal beliefs in the supernatural may improve T2DM self-management, but such interventions are lacking in China. This pilot randomized controlled trial (RCT) assessed the feasibility of a full-scale RCT to evaluate the efficacy of a supernatural beliefs-based intervention on T2DM management self-efficacy in China. In 2019, 62 T2DM patients were enrolled at two hospitals in Suzhou, China. Participants were randomly assigned to view a 30-s control or intervention video at baseline. The control video showed general diabetes self-management information. The intervention video showed identical information, but also indicated that some diabetics with supernatural beliefs (chao ziran xinnian) have lower glycemic levels, because their beliefs enhance their confidence in diabetes self-management. Development of the intervention was guided by the theory of planned behavior and literature on spiritual framing health interventions. Baseline and follow-up measures after two weeks were assessed by interviewer administered surveys in-person and by telephone, respectively. Diabetes management self-efficacy was assessed with the diabetes management self-efficacy scale. Randomization of intervention allocation appeared to be successful. However, follow-up retention was low, especially for the intervention group (3% vs. 31%). A full-size efficacy RCT using the current study design is unlikely to succeed. T2DM patients shown the supernatural beliefs-based intervention had significantly higher loss to follow-up that was insurmountable. T2DM patients in Suzhou, China may not be receptive to brief, non-tailored supernatural beliefs-based interventions delivered to a general population in clinical settings.

3.
Angew Chem Int Ed Engl ; : e202407277, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780892

RESUMO

Chiral multi-resonance thermally activated delayed fluorescence (CP-MR-TADF) materials hold promise for circularly polarized organic light-emitting diodes (CP-OLEDs) and 3D displays. Herein, we present two pairs of tetraborated intrinsically axial CP-MR-TADF materials, R/S-BDBF-BOH and R/S-BDBT-BOH, with conjugation-extended bidibenzo[b,d]furan and bidibenzo[b,d]thiophene as chiral sources, which effectively participate in the distribution of the frontier molecular orbitals. Due to the heavy-atom effect, sulfur atoms are introduced to accelerate the reverse intersystem crossing process and increase the efficiency of molecules. R/S-BDBF-BOH and R/S-BDBT-BOH manifest ultra-pure blue emission with a maximum at 458/459 nm with a full width at half maximum of 27 nm, photoluminescence quantum yields of 90 %/91 %, and dissymmetry factors (|gPL|) of 6.8×10-4/8.5×10-4, respectively. Correspondingly, the CP-OLEDs exhibit good performances with an external quantum efficiency of 30.1 % and |gEL| factors of 1.2×10-3.

4.
Plant Physiol ; 190(2): 1307-1320, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-35809075

RESUMO

Magnesium (Mg) is an essential metal for chlorophyll biosynthesis and other metabolic processes in plant cells. Mg is largely stored in the vacuole of various cell types and remobilized to meet cytoplasmic demand. However, the transport proteins responsible for mobilizing vacuolar Mg2+ remain unknown. Here, we identified two Arabidopsis (Arabidopsis thaliana) Mg2+ transporters (MAGNESIUM TRANSPORTER 1 and 2; MGT1 and MGT2) that facilitate Mg2+ mobilization from the vacuole, especially when external Mg supply is limited. In addition to a high degree of sequence similarity, MGT1 and MGT2 exhibited overlapping expression patterns in Arabidopsis tissues, implying functional redundancy. Indeed, the mgt1 mgt2 double mutant, but not mgt1 and mgt2 single mutants, showed exaggerated growth defects as compared to the wild type under low-Mg conditions, in accord with higher expression levels of Mg-starvation gene markers in the double mutant. However, overall Mg level was also higher in mgt1 mgt2, suggesting a defect in Mg2+ remobilization in response to Mg deficiency. Consistently, MGT1 and MGT2 localized to the tonoplast and rescued the yeast (Saccharomyces cerevisiae) mnr2Δ (manganese resistance 2) mutant strain lacking the vacuolar Mg2+ efflux transporter. In addition, disruption of MGT1 and MGT2 suppressed high-Mg sensitivity of calcineurin B-like 2 and 3 (cbl2 cbl3), a mutant defective in vacuolar Mg2+ sequestration, suggesting that vacuolar Mg2+ influx and efflux processes are antagonistic in a physiological context. We further crossed mgt1 mgt2 with mgt6, which lacks a plasma membrane MGT member involved in Mg2+ uptake, and found that the triple mutant was more sensitive to low-Mg conditions than either mgt1 mgt2 or mgt6. Hence, Mg2+ uptake (via MGT6) and vacuolar remobilization (through MGT1 and MGT2) work synergistically to achieve Mg2+ homeostasis in plants, especially under low-Mg supply in the environment.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Deficiência de Magnésio , Aclimatação , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Calcineurina/genética , Proteínas de Transporte/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Humanos , Magnésio/metabolismo , Deficiência de Magnésio/metabolismo , Manganês/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo
5.
Phys Rev Lett ; 131(10): 106801, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739384

RESUMO

Fractionalization without time-reversal symmetry breaking is a long-sought-after goal in the study of correlated phenomena. The earlier proposal of correlated insulating states at n±1/3 filling in twisted bilayer graphene and recent experimental observations of insulating states at those fillings strongly suggest that moiré graphene systems provide a new platform to realize time-reversal symmetric fractionalized states. However, the nature of fractional excitations and the effect of quantum fluctuation on the fractional correlated insulating states are unknown. We show that excitations of the fractional correlated insulator phases in the strong coupling limit carry fractional charges and exhibit fractonic restricted mobility. Upon introduction of quantum fluctuations, the resonance of "lemniscate" structured operators drives the system into quantum lemniscate liquid (QLL) or quantum lemniscate solid (QLS). We find an emergent U(1)×U(1) 1-form symmetry unifies distinct motions of the fractionally charged excitations in the strong coupling limit and in the QLL phase, while providing a new mechanism for fractional excitations in two dimensions. We predict emergent Luttinger liquid behavior upon dilute doping in the strong coupling limit due to restricted mobility and discuss implications at a general n±1/3 filling.

6.
Phys Chem Chem Phys ; 24(44): 27173-27183, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36321450

RESUMO

Herein, we have employed linear-response time dependent density functional theory (LR-TDDFT)-based nonadiabatic dynamics simulations to investigate the ultrafast charge transfer in a nonfullerene all-small-molecule donor-acceptor (D-A) system formed by a porphyrin small-molecule donor ZnP and a recently developed nonfullerene small-molecule acceptor 6TIC, during which the optimally tuned range-separated hybrid (OT-RSH) functional was adopted. In combination with static electronic structure calculations, several important conclusions were drawn. Firstly, the ZnP and 6TIC are more likely combined together non-covalently in parallel rather than in perpendicular to form ZnP-6TIC due to the much larger adsorption energies, i.e. -44.6 kcal mol-1vs. -25.2 kcal mol-1. Secondly, the excited state properties obtained by OT-RSH functionals seem more consistent with the experimental results compared to their untuned versions. Specifically, the energy of the lowest charge transfer (CT) state was predicted to be smaller than the lowest lying local excitation (LE) states using the OT-RSH functional-based LR-TDDFT calculations, which is beneficial for the charge transfer process that might be crucial for the high power conversion efficiency (PCE) achieved experimentally. In contrast, the untuned RS functionals all predict higher CT state energies, which is contradictory to the high PCE obtained in the experiment. Moreover, strong hybridization upon excitation between these states was revealed, which might be one of the reasons responsible for the high PCE observed in the experiment. Finally, ultrafast excited state relaxation can be completed within 500 fs due to the small energy gaps and the strong nonadiabatic couplings between these states, which is accompanied by ultrafast photoinduced electron transfer from ZnP to 6TIC and photoinduced hole transfer the other way around. The efficient charge transfer processes and the involvement of two charge generation channels might be another cause resulting in the excellent photovoltaic performance of ZnP-6TIC based OSCs. Our present work not only provides solid evidence for elucidating the underlying mechanism observed in previous experiments, but also suggests that the combination of OT-RSH functionals and LR-TDDFT-based nonadiabatic dynamics simulations might be a powerful tool for investigating the excited state dynamics of organic D-A systems, which is crucial for the theoretical design of novel OSCs with better performances in the future.

7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(2): 199-207, 2022 Apr.
Artigo em Zh | MEDLINE | ID: mdl-35538753

RESUMO

Objective To assess the psychological status of staff at the centers for disease control and prevention(CDC) in Sichuan during the outbreak of coronavirus disease 2019(COVID-19) and explore the influencing factors. Methods The staff at Sichuan provincial,municipal,and county(district)-level CDC were selected by convenience sampling.Their basic information,work status,training status,work difficulties,and support from the work group were collected from the self-filled questionnaires online.The Generalized Anxiety Disorder Scale and the 9-question Patient Health Questionnaire were respectively employed to measure the anxiety and depression of the staff.The stepwise Logistic regression was carried out to analyze the influencing factors of anxiety and depression in CDC staff. Results Among the 653 staff,58.35% and 50.06% presented anxiety and depression,respectively.The regression results showed that age(OR=0.95,95%CI=0.92-0.97) and mental support from the work group(OR=0.61,95%CI=0.45-0.82) were the protective factors while physical fatigue(OR=1.82,95%CI=1.20-2.74),work pressure(OR=1.61,95%CI=1.21-2.12),and insufficient protective equipment(OR=1.92,95%CI=1.06-3.49) were the risk factors for depression of CDC staff.Age(OR=0.97,95%CI=0.94-0.99),length of sleep per day(OR=0.74,95%CI=0.56-0.96),and participation in technical training(OR=0.33,95%CI=0.12-0.95) were the protective factors while mental fatigue(OR=1.68,95%CI=1.18-2.41),work pressure(OR=2.94,95%CI=2.08-4.17),and unclear incentive system for overtime(OR=1.99,95%CI=1.23-3.23) were the risk factors for the anxiety of CDC staff. Conclusion The anxiety and depression status of CDC staff during the COVID-19 outbreak were worrying,which were mainly affected by age,sleep,supply of protective equipment,incentive system,fatigue,and work pressure.


Assuntos
COVID-19 , Ansiedade/epidemiologia , Centers for Disease Control and Prevention, U.S. , China/epidemiologia , Estudos Transversais , Surtos de Doenças , Humanos , SARS-CoV-2 , Inquéritos e Questionários , Estados Unidos
8.
J Oral Pathol Med ; 50(2): 236-243, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33187014

RESUMO

BACKGROUND: Temporomandibular joint osteoarthritis (TMJOA) is a degenerative disease that gradually affects the articular cartilage, synovium, and bone structure. To date, the molecular mechanism of TMJOA pathogenesis remains unclear. The aim of this study was to explore the biological function of the micro-ribonucleic acid 101a-3p (miR-101a-3p) and its role in TMJOA. METHODS: We detected the effect of interleukin-1ß (IL-1ß) on chondrocyte proliferation using Cell Counting Kit-8 (CCK-8) technology. Using quantitative polymerase chain reaction (qPCR), we detected transcription levels of miR-101a-3p in a rat model with TMJOA and inflamed chondrocytes, as well as in a group of normal rats. The effect of miR-101a-3p on apoptosis was examined in vitro using flow cytometry (FCM). We then analyzed the target of miR-101a-3p via bioinformatics and confirmed it using a luciferase reporter assay (LRA). RESULTS: We showed that IL-1ß could inhibit proliferation of chondrocytes. We found that miR-101a-3p levels were significantly lower in the rat inflammation model with TMJOA and inflamed chondrocytes than in the normal group. Additionally, miR-101a-3p substantially promoted apoptosis of chondrocytes, and both bioinformatic analyses and LRA found that this miRNA targeted the genes ubiquitin-conjugating enzyme 2D1 (UBE2D1) and Frizzled class receptor 4 (FZD4). CONCLUSION: Our results suggested that miR-101a-3p was involved in the pathogenesis of TMJOA and that its mechanism was probably interaction with its target genes UBE2D1 and FZD4.


Assuntos
Cartilagem Articular , MicroRNAs , Osteoartrite , Animais , Apoptose/genética , Condrócitos , Receptores Frizzled , MicroRNAs/genética , Osteoartrite/genética , Ratos , Articulação Temporomandibular
9.
Fa Yi Xue Za Zhi ; 37(6): 847-858, 2021 Dec 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35243852

RESUMO

Since the beginning of this century, three types of coronavirus have widely transmitted and caused severe diseases and deaths, which strongly indicates that severe infectious diseases caused by coronavirus infection are not accidental events. Coronavirus-infected diseases are mainly manifested by respiratory symptoms, with multiple organ dysfunctions. Precisely investigating the pathological process, characteristics and pathogenesis of coronavirus-infected diseases will be beneficial for us to understand clinical manifestations and provide targeted suggestions on prophylaxis and treatment. This paper briefly reviews the pathological findings of three known coronavirus-infected diseases, and attempts to construct the pathological spectrum of coronavirus-infected diseases, aiming to provide reference and thinking for autopsy, histopathological examination and animal infection model study of coronavirus-infected diseases.


Assuntos
COVID-19 , Animais , Autopsia , Patologia Legal , SARS-CoV-2
10.
AAPS PharmSciTech ; 21(6): 234, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32794077

RESUMO

We investigated the pharmacokinetics of nimodipine (NMD) in rats plasma and tissues following intraocular (io), intragastric (ig), and intravenous (iv) administration at doses of 5.0 mg/kg io and iv and 10.0 mg/kg ig. After a single dose of NMD, plasma, heart, liver, spleen, lung, kidney, and brain samples were collected at the scheduled time points. The concentration of NMD in rat plasma and tissues was determined by high-performance liquid chromatography, and the main pharmacokinetic parameters were calculated and compared. NMD was rapidly absorbed and reached the maximum plasma concentration in approximately 5 min after io administration. The absolute bioavailability after io administration was higher than that after ig administration (40.05% vs. 5.67%). There were significant differences in the tissue distribution of NMD with different administration routes. After io administration, NMD was distributed more in the lung, spleen, and brain tissues, and less in the kidney. The maximum drug concentration after io administration in the heart, liver, spleen, lung, kidney, and brain was 1.00, 0.47, 2.02, 1.47, 0.22, and 5.79 times higher than that after via ig administration, and the area under the curve value was 0.59, 0.78, 1.71, 1.84, 0.25, and 4.59 times greater, respectively. Nimodipine appears to achieve systemic effects via io administration. Compared with ig, io administration could significantly increase NMD distribution in the brain tissue, indicating that NMD could be delivered to the brain via io administration.


Assuntos
Encéfalo/metabolismo , Injeções Intraoculares/métodos , Nimodipina/administração & dosagem , Nimodipina/sangue , Administração Intravenosa , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/sangue , Anti-Hipertensivos/farmacocinética , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Injeções Intraperitoneais , Injeções Intravenosas , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Nimodipina/farmacocinética , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
11.
Angew Chem Int Ed Engl ; 59(2): 721-724, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31622001

RESUMO

Precise control of the micro-/nanostructures of nanomaterials, such as hollow multi-shelled structures (HoMSs), has shown its great advantages in various applications. Now, the crystal structure of building blocks of HoMSs are controlled by introducing the lattice distortion in HoMSs, for the first time. The lattice distortion located at the nanoscale interface of SnS2 /SnO2 can provide additional active sites, which not only provide the catalytic activity under visible light but also improve the separation of photoexcited electron-hole pairs. Combined with the efficient light utilization, the natural advantage of HoMSs, a record catalytic activity was achieved in solid-gas system for CO2 reduction, with an excellent stability and 100 % CO selectivity without using any sensitizers or noble metals.

12.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067654

RESUMO

As a gaseous biological signaling molecule, nitric oxide (NO) regulates many physiological processes in plants. Over the last decades, this low molecular weight compound has been identified as a key signaling molecule to regulate plant stress responses, and also plays an important role in plant development. However, elucidation of the molecular mechanisms for NO in leaf development has so far been limited due to a lack of mutant resources. Here, we employed the NO-deficient mutant nia1nia2 to examine the role of NO in leaf development. We have found that nia1nia2 mutant plants displayed very different leaf phenotypes as compared to wild type Col-0. Further studies have shown that reactive oxygen species (ROS) levels are higher in nia1nia2 mutant plants. Interestingly, ROS-related enzymes ascorbate peroxidase (APX), catalases (CAT), and peroxidases (POD) have shown decreases in their activities. Our transcriptome data have revealed that the ROS synthesis gene RBOHD was enhanced in nia1nia2 mutants and the photosynthesis-related pathway was impaired, which suggests that NO is required for chloroplast development and leaf development. Together, these results imply that NO plays a significant role in plant leaf development by regulating ROS homeostasis.


Assuntos
Arabidopsis/metabolismo , Homeostase , Óxido Nítrico/metabolismo , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento
13.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(1): 57-62, 2019 Feb 28.
Artigo em Zh | MEDLINE | ID: mdl-30837043

RESUMO

Objective To explore the pharmacokinetics of nimodipine in plasma of rats after intraocular administration.Methods Totally 135 SD rats were randomly divided into three groups according to drug administration routes:intraocular(io group),intravenous (iv group),and intragastric (ig group). The doses were 5.0 mg/kg for IO and IV groups and 10.0 mg/kg for IG group. The serum nimodipine level was analyzed by high performance liquid chromatography. The main pharmacokinetic parameters were calculated and compared.Results The pharmacokinetic parameters in io group were as follows:Cmax:0.52 mg/ml;tmax:5.0 min;and AUC0-t:21.10 mg/(ml·min). The main pharmacokinetic parameters in iv group were as follows:Cmax:3.62 mg/ml;and AUC0-t:52.58 mg/(ml·min). The main pharmacokinetic parameters in ig group were as follows:Cmax:0.20 mg/ml;tmax:5.0 min;and AUC0-t:5.98 mg/(ml·min).Conclusions Nimodipine is rapidly absorbed after io administration,and the ophthalmic formulation has a higher bioavailability than the oral solution. Therefore,the io route may help to improve the treatment effectiveness of cardiovascular diseases.


Assuntos
Nimodipina/farmacocinética , Administração Intravenosa , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Ratos , Ratos Sprague-Dawley
14.
Planet Space Sci ; 153: 127-133, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29773922

RESUMO

The scale of the solar system is slowly changing, likely increasing as a result of solar mass loss, with additional change possible if there is a secular variation of the gravitational constant, G. The measurement of the change of scale could provide insight into the past and the future of the solar system, and in addition a better understanding of planetary motion and fundamental physics. Estimates for the expansion of the scale of the solar system are of order 1.5 cm year-1 AU-1, which over several years is an observable quantity with present-day laser ranging systems. This estimate suggests that laser measurements between planets could provide an accurate estimate of the solar system expansion rate. We examine distance measurements between three bodies in the inner solar system -- Earth's Moon, Mars and Venus -- and outline a mission concept for making the measurements. The concept involves placing spacecraft that carry laser ranging transponders in orbit around each body and measuring the distances between the three spacecraft over a period of several years. The analysis of these range measurements would allow the co-estimation of the spacecraft orbit, planetary ephemerides, other geophysical parameters related to the constitution and dynamics of the central bodies, and key geodetic parameters related to the solar system expansion, the Sun, and theoretical physics.

15.
Med Sci Monit ; 24: 1089-1096, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466323

RESUMO

BACKGROUND Spinal cord injury (SCI) causes a rapid loss of motor neurons, leading to weakness and paralysis. Transplantation of neural stem cells is known to restore the neuronal activity but is inefficient due to limited regenerative capability and low rate of survival. There has been an emphasis on the use of growth factors along with neural stem cells (NSCs) to enhance the neuronal recovery. Transplantation of recombinant NSCs with vascular endothelial growth factor (VEGF) might promote neuronal repair. This effect might be attributed to the reduced transient receptor potential vanilloid 1 (TRPV1) expression following transplantation. MATERIAL AND METHODS NSCs were cultured from the embryos of Sprague-Dawley rats (E12.5). Four group of rats (n=10, each) were subjected to SCI and allowed to recover for 1 week. Recombinant VEGF-NSCs, normal NSCs and PBS were intrathecally administered to the rats. VEGF and TRPV-1 expression at mRNA and protein level was evaluated. ELISA was performed to determine the release of neurotrophic factors after the transplantation. Motor neurons and axons were counted and the motor behavioral outcome was assessed using the rota-rod test. RESULTS VEGF-NSC transgene transplantation resulted in an enhanced neuronal repair and motor behavioral outcome compared to the normal NSCs transplanted group. VEGF-NSCs increased the release of neurotrophic factors and reduced the expression of TRPV1. CONCLUSIONS Recombinant VEGF-NSCs transplantation following SCI is more efficacious compared to normal NSC transplantation. This might also be related to a reduced pain in the process of recovery due to reduced TRPV1 expression.


Assuntos
Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/terapia , Transplante de Células-Tronco/métodos , Canais de Cátion TRPV/metabolismo , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Animais , Células Cultivadas , Feminino , Atividade Motora/fisiologia , Células-Tronco Neurais/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Transfecção
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 41(12): 1297-1304, 2016 Dec 28.
Artigo em Zh | MEDLINE | ID: mdl-28070042

RESUMO

OBJECTIVE: To investigate the effect of the jianpi-jiedu formula (JPJD) on the expression of angiogenesis-relevant genes in colon cancer.
 Methods: Crude extract was obtained from JPJD by water extract method. The effect of JPJD crude extract on colon cancer cell proliferation capacity was determined by MTT assays. The IC50 value was calculated by GraphPad Prism5 software. Affymetrix gene expression profiling chip was used to detect significant differences in expressions of genes after JPJD intervention, and pathway enrichment analysis was performed to analyze the differentially expressed genes. Ingenuity Pathway Analysis software was applied to analyze differentially expressed genes relevant to tumor angiogenesis based on mammalian target of rapamycin (mTOR) signaling pathway and then the network diagram was built. Western blot was used to verify the protein levels of key genes related to tumor angiogenesis.
 Results: JPJD crud extract inhibited the proliferation capacity in colon cancer cells. The IC50 values in 24, 48, and 72 hours after treatment were 13.060, 9.646 and 8.448 mg/mL, respectively. The results of chip showed that 218 genes significantly upgraded, and 252 genes significantly downgraded after JPJD treatment. Most of the genes were related to the function of biosynthesis, metabolism, cell apoptosis, antigen extraction, angiogenesis and so on. There were 12 differentially expressed angiogenesis genes. IPA software analysis showed that the JPJD downregulated expression of sphingomyelin phosphodiesterase 3 (SMPD3), VEGF, vascular endothelial growth factor A (VEGFA), integrin subunit alpha 1 (ITGA1), cathepsin B (CTSB), and cathepsin S (CTSS) genes, while upregulated expressions of GAB2 and plasminogen activator, urokinase receptor (PLAUR) genes in the colorectal cancer cell. Western blot results demonstrated that JPJD obviously downregulated expressions of phospho-mTOR (P-mTOR), signal transducer and activator of transcription 3 (STAT3), hypoxia inducible factor-1α (HIF-1α), and VEGF proteins, while obviously upregulated the level of phospho-P53 (P-P53) protein.
 Conclusion: JPJD may inhibit colorectal tumor angiogenesis through regulation of the mTOR-HIF-1α-VEGF signal pathway.


Assuntos
Linhagem Celular Tumoral/efeitos dos fármacos , Neoplasias Colorretais/genética , Medicamentos de Ervas Chinesas/farmacologia , Animais , Western Blotting , Catepsina B/efeitos dos fármacos , Catepsina B/metabolismo , Catepsinas/efeitos dos fármacos , Catepsinas/metabolismo , Neoplasias Colorretais/irrigação sanguínea , Regulação para Baixo , Perfilação da Expressão Gênica/métodos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Cadeias alfa de Integrinas/efeitos dos fármacos , Cadeias alfa de Integrinas/metabolismo , Neovascularização Patológica/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/efeitos dos fármacos , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Fator de Transcrição STAT3/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Esfingomielina Fosfodiesterase/efeitos dos fármacos , Esfingomielina Fosfodiesterase/metabolismo , Serina-Treonina Quinases TOR/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 41(11): 1128-1136, 2016 Nov 28.
Artigo em Zh | MEDLINE | ID: mdl-27932756

RESUMO

OBJECTIVE: To investigate the effect of jianpi-jiedu (JPJD) prescription-contained serum on colorectal cancer SW48 cell proliferation and the underlying mechanisms.
 Methods: Crude extract from JPJD was made by water extract method and the main components of crude extract from JPJD were analyzed by ultra-performance liquid phase high resolution time of flight mass spectrometry (UPLC-Q-TOF/MS). The low, medium, and high-concentration of JPJD-contained serum were prepared by the serum pharmacological method. The effect of serum containing JPJD on SW48 cell proliferation was determined by MTT assay. The cell cycle was detected by flow cytometric method. The protein levels of mammalian target of rapamycin (mTOR), phospho-mTOR, P-P53, and -P21, and the mRNA level of mTOR were examined by Western blot and RT-PCR, respectively.
 Results: Seven compounds including calycosin-7-glucoside, astragaloside, ginsenoside-Re, ginsenoside-Rb1, glycyrrhizinic acid, apigenin, atractylenolide-II were identified. MTT assays demonstrated that the SW48 cell proliferation was inhibited by medium and high concentration of JPJD-contained serum and the percentages of cells at G1 phase in SW48 cell cultured in the medium and high concentration of JPJD serum group were significantly higher than those in the control group (P<0.05). Meanwhile, the levels of mTOR mRNA and phospho-mTOR protein in the medium and high concentration of JPJD serum groups were substantially lower than those in the control group (P<0.05). Conversely, the expressions of phospho-P53 and P21 protein were significantly increased in the medium and high concentration of JPJD serum group compared with those in the control group.
 Conclusion: JPJD prescription-contained serum can inhibit SW48 cell proliferation, which may be related to mTOR-P53-P21 signaling pathways.


Assuntos
Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Animais , Apigenina , Western Blotting , Ciclo Celular , Divisão Celular , Proliferação de Células/genética , Neoplasias Colorretais , Inibidor de Quinase Dependente de Ciclina p21/efeitos dos fármacos , Citometria de Fluxo , Ginsenosídeos , Ácido Glicirrízico , Humanos , Lactonas , Fosforilação/genética , RNA Mensageiro , Saponinas , Sesquiterpenos , Transdução de Sinais , Serina-Treonina Quinases TOR/efeitos dos fármacos , Triterpenos , Proteína Supressora de Tumor p53/efeitos dos fármacos
18.
Org Biomol Chem ; 13(7): 2122-8, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25526239

RESUMO

An unexpected Sc(OTf)3-catalyzed and air-mediated cascade reaction of o-aminoacetophenones with methanamines was discovered as an efficient synthetic approach to a novel class of fluorescent fused-four-ring dibenzo[b,h][1,6]naphthyridine derivatives. Two possible mechanisms of the reaction were proposed. The photophysical properties of the dibenzo[b,h][1,6]naphthyridine were initially considered.

19.
Nano Lett ; 14(11): 6679-84, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25317725

RESUMO

Herein, uniform multishelled TiO2 hollow microspheres were synthesized, especially 3- and 4-shelled TiO2 hollow microspheres were synthesized for the first time by a simple sacrificial method capable of controlling the shell thickness, intershell spacing, and number of internal multishells, which are achieved by controlling the size, charge, and diffusion rate of the titanium coordination ions as well as the calcination process. Used as anodes for lithium ion batteries, the multishelled TiO2 hollow microspheres show excellent rate capacity, good cycling performance, and high specific capacity. A superior capacity, up to 237 mAh/g with minimal irreversible capacity after 100 cycles is achieved at a current rate of 1 C (167.5 mA/g), and a capacity of 119 mAh/g is achieved at a current rate of 10 C even after 1200 cycles.

20.
Zhongguo Zhong Yao Za Zhi ; 40(16): 3220-3, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26790296

RESUMO

Ten isoflavonoids were isolated from the heartwoods of Caragana changduensis Lion f. by means of various column chromatographic techniques. Based on the detailed spectral data analysis (MS and NMR), as well as comparison with the literatures, their chemical structures were determined as 7,2'-dihydroxy-8,4'-dimethoxyisoflavone (1), 4'-hydroxy-7,3'-dimethoxyisoflavone (2), 5, 7, 4'-trihydroxy-2',5'-dimethoxyisoflavone (3), prunetin (4), afrormosin (5), odoratin (6), genistein (7), texasin (8), pratensein (9), and 6,7,3'-trihydroxy-4'-methoxyisoflavone (10). Among them, compounds 1-3 and 9-10 were isolated from the Caragana genus for the first time. All the compounds were obtained from this species for the first time. In the preliminary assays, compounds 1, 2, 6, and 7 possessed significant inhibitory effects on NO production, with IC50 values of 48.12, 25.32, 62.71, 43.59 µmol x L(-1), respectively.


Assuntos
Caragana/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Isoflavonas/química , Isoflavonas/farmacologia , Óxido Nítrico/antagonistas & inibidores , Animais , Medicamentos de Ervas Chinesas/isolamento & purificação , Isoflavonas/isolamento & purificação , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Células RAW 264.7
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