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1.
Zhongguo Zhen Jiu ; 43(11): 1338-1342, 2023 Aug 19.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37984925

RESUMO

Meridian-tendon is a central concept in meridian theory of TCM, and its basic research has been increasingly emphasized. While there is no unified understanding of the essence of meridian-tendon, the concept that function of fascia could partially reflect the functions of meridian-tendons has reached consensus in the academic community. This article suggests that under the guidance of meridian-tendon theory, based on previous research foundation of fascia, focusing on adopting fascia research methods, the mechanisms of tender point hyperalgesia and abnormal proliferation related to meridian lesions should be adopted to explain yitong weishu (taking the worst painful sites of muscle spasm as the points), and the mechanisms of meridian intervention efficacy should be adopted to explain yizhi weishu (feelings from patients and acupuncture operators). Furthermore, this article provides an analysis of the future trends in basic research of meridian tendons.


Assuntos
Terapia por Acupuntura , Acupuntura , Meridianos , Humanos , Tendões , Dor , Projetos de Pesquisa , Pontos de Acupuntura
2.
Zhongguo Zhen Jiu ; 43(9): 977-81, 2023 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-37697869

RESUMO

As a diagnostic method to guide the treatment of sinew/fascia diseases, jingjin (muscle regions of meridians) differentiation is an important component of syndrome differentiation system of acupuncture and moxibustion. In clinical practice, because of the limitations of the ideological guidance of the holistic view, the systemic and dialectical thinking and the syndrome element collection, the system of diagnosis and treatment of sinew/fascia diseases is not comprehensive. Through combing the origin of the holistic view of jingjin, the paper expounds the differentiation framework of sinew/fascia diseases from 4 aspects of differentiation, i.e. the location of disease, etiology, nature of disease and condition of disease. It suggests to construct jingjin differentiation system by taking the holistic ideas as the core, the syndrome element research as the common method and the evidence-based medicine as the theoretical basis so that the thinking of syndrome differentiation and the diagnostic approaches based on jingjin theory can be enriched.


Assuntos
Terapia por Acupuntura , Meridianos , Moxibustão , Humanos , Medicina Baseada em Evidências , Idioma , Síndrome
3.
Se Pu ; 41(7): 562-571, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37387277

RESUMO

As modified ligands with a wide range of sources, abundant functional groups, and good biocompatibility, polymers have been widely used in the development of silica-based chromatographic stationary phases. In this study, a poly(styrene-acrylic acid) copolymer-modified silica stationary phase (SiO2@P(St-b-AA)) was prepared via one-pot free-radical polymerization. In this stationary phase, styrene and acrylic acid were used as functional repeating units for polymerization and vinyltrimethoxylsilane (VTMS) was used as a silane coupling agent to link the copolymer and silica. Various characterization methods, such as Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), N2 adsorption-desorption analysis, and Zeta potential analysis, confirmed the successful preparation of the SiO2@P(St-b-AA) stationary phase, which had a well-maintained uniform spherical and mesoporous structure. The retention mechanisms and separation performance of the SiO2@P(St-b-AA) stationary phase in multiple separation modes were then evaluated. Hydrophobic and hydrophilic analytes as well as ionic compounds were selected as probes for different separation modes, and changes in the retention of the analytes under various chromatographic conditions, including different methanol or acetonitrile contents and buffer pH values, were investigated. In reversed-phase liquid chromatography (RPLC) mode, the retention factors of alkyl benzenes and polycyclic aromatic hydrocarbons (PAHs) on the stationary phase decreased with increasing methanol content in the mobile phase. This finding could be attributed to the hydrophobic and π-π interactions between the benzene ring and analytes. The retention changes of alkyl benzenes and PAHs revealed that the SiO2@P(St-b-AA) stationary phase, similar to the C18 stationary phase, exhibited a typical reversed-phase retention behavior. In hydrophilic interaction liquid chromatography (HILIC) mode, as the acetonitrile content increased, the retention factors of hydrophilic analytes gradually increased, and a typical hydrophilic interaction retention mechanism was inferred. In addition to hydrophilic interaction, the stationary phase also demonstrated hydrogen-bonding and electrostatic interactions with the analytes. Compared with the C18 and Amide stationary phases prepared by our groups, the SiO2@P(St-b-AA) stationary phase exhibited excellent separation performance for the model analytes in the RPLC and HILIC modes. Owing to the presence of charged carboxylic acid groups in the SiO2@P(St-b-AA) stationary phase, exploring its retention mechanism in ionic exchange chromatography (IEC) mode is of great importance. The effect of the mobile phase pH on the retention time of organic bases and acids was further studied to explore the electrostatic interaction between the stationary phase and charged analytes. The results revealed that the stationary phase has weak cation exchange ability toward organic bases and electrostatically repels organic acids. Moreover, the retention of organic bases and acids on the stationary phase was influenced by the analyte structure and mobile phase. Thus, the SiO2@P(St-b-AA) stationary phase could provide multiple interactions, as demonstrated by the separation modes described above. The SiO2@P(St-b-AA) stationary phase showed excellent performance and reproducibility in the separation of mixed samples with different polar components, indicating that it has promising application potential in mixed-mode liquid chromatography. Further investigation of the proposed method confirmed its repeatability and stability. In summary, this study not only described a novel stationary phase that could be used in RPLC, HILIC, and IEC modes but also presented a facile "one-pot" preparation approach that could provide a new route for the development of novel polymer-modified silica stationary phases.

5.
Chem Sci ; 14(6): 1472-1478, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36794184

RESUMO

The modern technology for acetylene production is inevitably accompanied by the contamination of carbon dioxide and moisture impurities. Metal-organic frameworks (MOFs), with rational configurations of fluorine as the hydrogen-bonding acceptor (HBA), exhibit excellent affinities to capture acetylene from the gas mixtures. Currently, most research studies feature anionic fluorine groups as structural pillars (e.g., SiF6 2-, TiF6 2-, NbOF5 2-), whereas in situ insertion of fluorine into metal clusters is rather challenging. Herein, we report a unique fluorine-bridged Fe-MOF, i.e., DNL-9(Fe), which is assembled by mixed-valence FeIIFeIII clusters and renewable organic ligands. The fluorine species in the coordination-saturated structure offer superior C2H2-favored adsorption sites facilitated by hydrogen bonding, with a lower C2H2 adsorption enthalpy than other reported HBA-MOFs, demonstrated by static/dynamic adsorption tests and theoretical calculations. Importantly, DNL-9(Fe) shows exceptional hydrochemical stability under aqueous, acidic, and basic conditions, and its intriguing performance for C2H2/CO2 separation was even maintained at a high relative humidity of 90%.

6.
Nucleic Acids Res ; 50(16): 9072-9082, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-35979954

RESUMO

The static and dynamic structures of DNA duplexes affected by 5S-Tg (Tg, Thymine glycol) epimers were studied using MD simulations and Markov State Models (MSMs) analysis. The results show that the 5S,6S-Tg base caused little perturbation to the helix, and the base-flipping barrier was determined to be 4.4 kcal mol-1 through the use of enhanced sampling meta-eABF calculations, comparable to 5.4 kcal mol-1 of the corresponding thymine flipping. Two conformations with the different hydrogen bond structures between 5S,6R-Tg and A19 were identified in several independent MD trajectories. The 5S,6R-Tg:O6HO6•••N1:A19 hydrogen bond is present in the high-energy conformation displaying a clear helical distortion, and near barrier-free Tg base flipping. The low-energy conformation always maintains Watson-Crick base pairing between 5S,6R-Tg and A19, and 5S-Tg base flipping is accompanied by a small barrier of ca. 2.0 KBT (T = 298 K). The same conformations are observed in the MSMs analysis. Moreover, the transition path and metastable structures of the damaged base flipping are for the first time verified through MSMs analysis. The data clearly show that the epimers have completely different influence on the stability of the DNA duplex, thus implying different enzymatic mechanisms for DNA repair.


Assuntos
Reparo do DNA , DNA , Pareamento de Bases , DNA/química , Dano ao DNA , Ligação de Hidrogênio , Conformação de Ácido Nucleico , Termodinâmica
7.
J Chem Inf Model ; 62(2): 386-398, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-34994562

RESUMO

Damaged or mismatched DNA bases are normally thought to be able to flip out of the helical stack, providing enzymes with access to the faulty genetic information otherwise hidden inside the helix. Thymine glycol (Tg) is one of the most common products of nucleic acid damage. However, the static and dynamic structures of DNA duplexes affected by 5R-Tg epimers are still not clearly understood, including the ability of these to undergo spontaneous base flipping. Structural effects of the 5R-Tg epimers on the duplex DNA are herein studied using molecular dynamics together with reliable DFT based calculations. In comparison with the corresponding intact DNA, the cis-5R,6S-Tg epimer base causes little perturbation to the duplex DNA, and a barrier of 4.9 kcal mol-1 is obtained by meta-eABF for cis-5R,6S-Tg base flipping out of the duplex DNA, comparable to the 5.4 kcal mol-1 obtained for the corresponding thymine flipping in intact DNA. For the trans-5R,6R-Tg epimer, three stable local structures were identified, of which the most stable disrupts the Watson-Crick hydrogen-bonded G5/C20 base pair, leading to conformational distortion of the duplex. Interestingly, the relative barrier height of the 5R-Tg flipping is only 1.0 kcal mol-1 for one of these trans-5R,6R-Tg epimers. Water bridge interactions were identified to be essential for 5R-Tg flipping. The study clearly demonstrates the occurrence of partial trans-5R,6R-Tg epimer flipping in solution.


Assuntos
DNA , Timina , Pareamento de Bases , DNA/química , Dano ao DNA , Conformação de Ácido Nucleico , Termodinâmica , Timina/análogos & derivados , Timina/química
8.
Org Biomol Chem ; 18(18): 3536-3543, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32338268

RESUMO

Selective C-H oxidation is thought to be a highly suitable strategy for building synthetic blocks and generating bioactive compounds. Noncovalent DNA catalysis for C-H bond cleavage is studied for the first time in order to delineate the so-called 'oxidation enhancement effect' on oxidatively generated damage in DNA duplex structures. Herein, DFT methods have been used to gain insight into the reactivity of the 5-hydroxy-6-peroxyl-5,6-dihydrothymine radical using ten single-stranded and duplex DNA models. Reliable M06-2X/6-31+G(d,p) calculations indicate that hydrogen bonding between the complementary base pairs significantly enhances the reactivity of the thymine peroxyl radical in duplex DNA models towards the C1'-H1' bond. An excellent linear relationship of the reaction activation barrier vs. the difference between the bond dissociation free energies (BDFE) of the C-H and O-H bonds is observed. With the noted role of charge transfer from LPO4' on 2-deoxyribose to its adjacent C1'-H1' anti-bonding orbital, a hyperconjugation effect is proposed to explain the reason why the barrier heights are close to each other for the studied duplex DNA models. The difference in the reactivity of the thymine peroxyl radical in the duplex and related single-strand DNA models is rationalized in terms of the preparatory energy and the optimal σC1'-H1' and oxyl-p based π*-orbital interactions.


Assuntos
DNA/química , Teoria da Densidade Funcional , Peróxidos/química , Pirimidinas/química , Estrutura Molecular
9.
Chem Sci ; 11(32): 8373-8387, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-33384860

RESUMO

Large-scale targeted exploration of metal-organic frameworks (MOFs) with characteristics such as specific surface chemistry or metal-cluster family has not been investigated so far. These definitions are particularly important because they can define the way MOFs interact with specific molecules (e.g. their hydrophilic/phobic character) or their physicochemical stability. We report here the development of algorithms to break down the overarching family of MOFs into a number of subgroups according to some of their key chemical and physical features. Available within the Cambridge Crystallographic Data Centre's (CCDC) software, we introduce new approaches to allow researchers to browse and efficiently look for targeted MOF families based on some of the most well-known secondary building units. We then classify them in terms of their crystalline properties: metal-cluster, network and pore dimensionality, surface chemistry (i.e. functional groups) and chirality. This dynamic database and family of algorithms allow experimentalists and computational users to benefit from the developed criteria to look for specific classes of MOFs but also enable users - and encourage them - to develop additional MOF queries based on desired chemistries. These tools are backed-up by an interactive web-based data explorer containing all the data obtained. We also demonstrate the usefulness of these tools with a high-throughput screening for hydrogen storage at room temperature. This toolbox, integrated in the CCDC software, will guide future exploration of MOFs and similar materials, as well as their design and development for an ever-increasing range of potential applications.

10.
Haematologica ; 105(4): 1021-1031, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31289198

RESUMO

Aberrant expression of CDK9/cyclin T1 has been found in diffuse large B-cell lymphoma (DLBCL), and suggests that CDK9 is a potential therapeutic target for DLBCL. Here, we firstly demonstrated that CDKI-73, a novel cyclin-dependent kinases (CDK) inhibitor, potently blocks CDK9, triggered apoptosis and dramatically repressed DLBCL cell growth owing to CDK9 inhibition. CDK9 inhibitors specifically elevated the trimethylation of H3K27, which we speculate was due to reduced expression of JMJD3/UTX. Considering the important role of the trimethylation of H3K27 in tumor progression, the synergistic effect of the combination therapy of CDK9 inhibitors with EZH2 inhibitors was investigated. EZH2 inhibitors reversed the upregulation of trimethylation of H3K27, and synergistically inhibited DLBCL and other solid tumors growth in vitro and in vivo These findings provide a rational basis for the application of CDK9 inhibitors in combination with EZH2 inhibitors in clinical trials.


Assuntos
Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Linfoma Difuso de Grandes Células B , Apoptose , Pontos de Checagem do Ciclo Celular , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Ativação Transcricional , Regulação para Cima
11.
ACS Omega ; 3(1): 406-413, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30023780

RESUMO

In this article, the silk fibroin (SF)/graphene oxide (GO)-blended nanofibers with one bioinspired nanostructure are fabricated via electrospinning. The morphology, chemical structure, antibacterial activity, and biocompatibility of the blending nanofibers are investigated. The results indicate that GO plays an important role in preparing the distinctive bioinspired structure. The antibacterial activity and in vivo cell culture test demonstrate that blending of GO could improve the antibacterial activity and biocompatibility of SF nanofibers. The blended nanofibers developed in this study may have considerable potential for wound dressing applications.

12.
Neural Regen Res ; 13(2): 280-288, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29557378

RESUMO

Dexmedetomidine has sedative, anxiolytic, analgesic, anti-sympathetic, and anti-shivering effects. Dexmedetomidine might be effective in combination with sevoflurane for anesthesia, but prospective randomized controlled clinical trials with which to verify this hypothesis are lacking. In total, 120 patients who underwent embolization of an intracranial aneurysm were recruited from Anhui Provincial Hospital and Renmin Hospital of Wuhan University of China and randomly allocated to two groups. After intraoperative administration of 2% to 3% sevoflurane inhalation, one group of patients received pump-controlled intravenous injection of 1.0 µg/kg dexmedetomidine for 15 minutes followed by maintenance with 0.3 µg/kg/h until the end of surgery; the other group of patients only underwent pump-controlled infusion of saline. Bispectral index monitoring revealed that dexmedetomidine-assisted anesthesia can shorten the recovery time of spontaneous breathing, time to eye opening, and time to laryngeal mask removal. Before anesthetic induction and immediately after laryngeal mask airway removal, the glucose and lactate levels were low, the S100ß and neuron-specific enolase levels were low, the perioperative blood pressure and heart rate were stable, and postoperative delirium was minimal. These findings indicate that dexmedetomidine can effectively assist sevoflurane for anesthesia during surgical embolization of intracranial aneurysms, shorten the time to consciousness and extubation, reduce the stress response and energy metabolism, stabilize hemodynamic parameters, and reduce adverse reactions, thereby reducing the damage to the central nervous system. This trial was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) (registration number: ChiCTR-IPR-16008113).

13.
Int J Biol Macromol ; 111: 237-246, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29320721

RESUMO

Silk fibroin (SF) is blended with graphene oxide (GO) to prepare the strong and biocompatible three dimensional porous SF/GO blended scaffold via phase separation. GO could be well dispersed in SF solution and GO could also be well distributed in the SF scaffold. Furthermore, the introduction of GO can lead to structural change in the bended scaffold. Higher concentration of GO resulted in more compact structure and smaller pore size of the composite scaffolds without decreasing their porosity. Scanning electron microscopy and energy dispersive spectrometry results also reveal that SF and GO are homogeneous blended together. Analysis of chemical structures of the scaffold shows that addition of GO do not affect the crystalline structure of SF and it is evenly blended with SF. The blended scaffold has significantly higher breaking strength than the pure SF scaffold. In vitro study indicates that both pure SF scaffold and SF/GO composite scaffold support growth and proliferation of MC3T3-E1 osteoprogenitor cells. However, the addition of GO contribute to the proliferation of MC3T3-E1 osteoprogenitor. The testing results show that the blended scaffold is an appropriate candidate for tissue engineering.


Assuntos
Fibroínas/química , Grafite/química , Seda/química , Engenharia Tecidual , Células 3T3 , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Durapatita/química , Fibroínas/farmacologia , Grafite/farmacologia , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Óxidos/química , Porosidade , Seda/farmacologia , Alicerces Teciduais
14.
Chem Commun (Camb) ; 53(83): 11437-11440, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-28976523

RESUMO

In this work, we show a solvent-free "explosive" synthesis (SFES) method for the ultrafast and low-cost synthesis of metal-formate frameworks (MFFs). A combination of experiments and in-depth molecular modelling analysis - using grand canonical Monte Carlo (GCMC) simulations - of the adsorption performance of the synthesized nickel-formate framework (Ni-FA) revealed extremely high quality products with permanent porosity, prominent CH4/N2 selectivity (ca. 6.0), and good CH4 adsorption capacity (ca. 0.80 mmol g-1 or 33.97 cm3 cm-3) at 1 bar and 298 K. This performance is superior to those of many other state-of-the-art porous materials.

15.
Sci Rep ; 7: 42328, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28176873

RESUMO

It is widely recognized that the long-term growth of forests benefits biomass carbon (C) sequestration, but it is not known whether the long-term growth of forests would also benefit soil C sequestration. We selected 79 representative soil profiles and investigated the influence of the forest stand age on the soil C dynamics of three soil layers (0-10, 10-20 and 20-30 cm) in temperate broadleaved forests in East China. The results suggest that the soil C density in temperature broadleaved forests significantly changes with the stand age, following a convex parabolic curve. At an early stand age, the soil C density usually increases, reaching its peak value at a pre-mature stand age (approximately 50 years old). At later stand ages, the soil C density usually decreases. Therefore, our results reveal a turning point in the soil C density at a pre-mature stand age. The long-term growth of temperate broadleaved forests after pre-mature stand age no longer benefits soil C accumulation, probably promotes topsoil C loss. In addition, we found that the soil C density in the upper soil layer usually changes with the forest stand development more significantly than that in deeper soil layers.


Assuntos
Carbono/análise , Floresta Úmida , Solo/química , China , Geografia , Fatores de Tempo
16.
Int J Mol Sci ; 17(10)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27669232

RESUMO

Hepatocellular carcinoma (HCC) is the most common subtype of liver malignancy, and it is characterized by poor prognosis because of cancer stem cell (CSC)-mediated high postsurgical recurrence rates. Thus, targeting CSCs, or HCC cells with CSC-like properties, is an effective strategy for HCC therapy. Here, using long noncoding RNA (lncRNA) microarray analysis, we identified a novel lncRNA termed lncCAMTA1 that is increased in both liver CSCs and HCC. High lncCAMTA1 expression in HCC indicates poor clinical outcome. In vitro and in vivo functional experiments showed that overexpression of lncCAMTA1 promotes HCC cell proliferation, CSC-like properties, and tumorigenesis. Conversely, depletion of lncCAMTA1 inhibits HCC cell proliferation, CSC-like properties, and tumorigenesis. Mechanistically, we demonstrated that lncCAMTA1 physically associates with the calmodulin binding transcription activator 1 (CAMTA1) promoter, induces a repressive chromatin structure, and inhibits CAMTA1 transcription. Furthermore, CAMTA1 is required for the effects of lncCAMTA1 on HCC cell proliferation and CSC-like properties, and the expression of lncCAMTA1 and CAMTA1 is significantly negatively correlated in HCC tissues. Collectively, our study revealed the important roles and underlying molecular mechanisms of lncCAMTA1 on HCC, and suggested that lncCAMTA1 could be an effective prognostic factor and a potential therapeutic target for HCC.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , RNA Longo não Codificante/metabolismo , Transativadores/genética , Animais , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Cromatina/química , Bases de Dados Factuais , Intervalo Livre de Doença , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Oligonucleotídeos Antissenso/metabolismo , Regiões Promotoras Genéticas , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Transativadores/antagonistas & inibidores , Transativadores/metabolismo , Transplante Heterólogo
17.
Chem Asian J ; 11(21): 3014-3017, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27642711

RESUMO

Simultaneous improvement in adsorption selectivity and capacity for single adsorbents is challenging but counting for much in adsorptive separations. To this end, a formate metal-organic framework and activated carbon fiber composite was synthesized in our work by a simple two-step process, involving homogeneous precipitation of a MOF precursor on an activated carbon fiber and subsequent template replication. The resultant core-shell composite, ACF@[Ni3 (HCOO)6 ], exhibited optimized adsorption performance both in selectivity and capacity for the separation of CH4 /N2 to most of state-of-the-art adsorbents.

18.
Acta Pharmacol Sin ; 37(11): 1481-1489, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27569395

RESUMO

AIM: LS-007 is a CDK inhibitor, which exhibits potent antitumor activity against chronic lymphocytic leukemia and ovarian cancer cells. In this study, we further evaluated the antitumor activity of LS-007 alone and in combination with a Bcl-2 inhibitor ABT-199 in acute leukemia (AL) cells. METHODS: Cell viability was detected using resazurin assay, and cell apoptosis was examined using Annexin V/PI double staining and flow cytometry. The inhibition of LS-007 on kinases was evaluated with the mobility shift assay or ELISA. The expression of relevant signaling molecules was assessed using Western blotting and RT-PCR. Primary lymphocytes from patients with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) were separated using Ficoll-Paque PLUS. RESULTS: LS-007 inhibited the proliferation of 6 AL cell lines with IC50 values of 100-200 nmol/L, and decreased the survival of ALL and AML patient-derived lymphocytes with mean LD50 value of 67 and 102 nmol/L, respectively. In kinase assays in vitro, LS-007 was more selective for the CDK family, inhibiting CDK2, CDK9, CDK1 and CDK4 at low nanomolar concentrations. In HL-60 and CCRF-CEM cells, LS-007 (0.1-0.4 µmol/L) dose-dependently induced cell apoptosis predominantly through CDK9 inhibition-related dephosphorylation at the ser2 residue of RNA pol II and the corresponding depletion of anti-apoptotic proteins, especially Mcl-1 and XIAP. LS-007 (0.2 and 0.4 µmol/L) also induced cell apoptosis in the patient-derived lymphocytes. In HL-60, CCRF-CEM and Molt-4 cells, combined application of LS-007 with ABT-199 (1 or 2 µmol/L) markedly increased cell apoptosis with a maximal decrease in the XIAP levels as compared with either drug used alone. CONCLUSION: CDK inhibitor LS-007 potently inhibits the established human AL cell lines and primary AL blasts, and it also shows remarkable synergy with Bcl-2 inhibitor ABT-199.


Assuntos
Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Criança , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1669-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26601388

RESUMO

There are two major problems of sophisticated vegetation classification (SVC) using hyperspectral image. Classification results using only spectral information can hardly meet the application requirements with the needed vegetation type becoming more sophisticated. And applications of classification image are also limited due to salt and pepper noise. Therefore the SVC strategy based on construction and optimization of vegetation feature band set (FBS) is proposed. Besides spectral and texture features of original image, 30 spectral indices which are sensitive to biological parameters of vegetation are added into FBS in order to improve the separability between different kinds of vegetation. And to achieve the same goal a spectral-dimension optimization algorithm of FBS based on class-pair separability (CPS) is also proposed. A spatial-dimension optimization algorithm of FBS based on neighborhood pixels' spectral angle distance (NPSAD) is proposed so that detailed information can be kept during the image smoothing process. The results of SVC experiments based on airborne hyperspectral image show that the proposed method can significantly improve the accuracy of SVC so that some widespread application prospects like identification of crop species, monitoring of invasive species and precision agriculture are expectable.


Assuntos
Plantas/classificação , Análise Espectral , Algoritmos
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 975-81, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197586

RESUMO

Spectral index method was widely applied to the inversion of crop chlorophyll content. In the present study, PSR3500 spectrometer and SPAD-502 chlorophyll fluorometer were used to acquire the spectrum and relative chlorophyll content (SPAD value) of winter wheat leaves on May 2nd 2013 when it was at the jointing stage of winter wheat. Then the measured spectra were resampled to simulate TM multispectral data and Hyperion hyperspectral data respectively, using the Gaussian spectral response function. We chose four typical spectral indices including normalized difference vegetation index (NDVD, triangle vegetation index (TVI), the ratio of modified transformed chlorophyll absorption ratio index (MCARI) to optimized soil adjusted vegetation index (OSAVI) (MCARI/OSAVI) and vegetation index based on universal pattern decomposition (VIUPD), which were constructed with the feature bands sensitive to the vegetation chlorophyll. After calculating these spectral indices based on the resampling TM and Hyperion data, the regression equation between spectral indices and chlorophyll content was established. For TM, the result indicates that VIUPD has the best correlation with chlorophyll (R2 = 0.819 7) followed by NDVI (R2 = 0.791 8), while MCARI/OSAVI and TVI also show a good correlation with R2 higher than 0.5. For the simulated Hyperion data, VIUPD again ranks first with R2 = 0.817 1, followed by MCARI/OSAVI (R2 = 0.658 6), while NDVI and TVI show very low values with R2 less than 0.2. It was demonstrated that VIUPD has the best accuracy and stability to estimate chlorophyll of winter wheat whether using simulated TM data or Hyperion data, which reaffirms that VIUPD is comparatively sensor independent. The chlorophyll estimation accuracy and stability of MCARI/OSAVI also works well, partly because OSAVI could reduce the influence of backgrounds. Two broadband spectral indices NDVI and TVI are weak for the chlorophyll estimation of simulated Hyperion data mainly because of their dependence on few bands and the strong influence of atmosphere, solar altitude, viewing angle of sensor, background and so on. In conclusion, the stability and consistency of chlorophyll estimation is equally important to the estimation accuracy by spectral index method. VIUPD introduced in the study has the best performance to estimate winter wheat chlorophyll, which illustrates its potential ability in the area of estimating vegetation biochemical parameters.


Assuntos
Clorofila/análise , Folhas de Planta/química , Análise Espectral , Triticum/química , Solo
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