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1.
J Agric Food Chem ; 72(15): 8618-8631, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38569082

RESUMO

Daidzein (DAN) is an isoflavone, and it is often found in its natural form in soybean and food supplements. DAN has poor bioavailability owing to its extremely low water solubility and first-pass metabolism. Herein, we hypothesized that a bioactivatable natural amino acid-bearing carbamate prodrug strategy could increase the water solubility and metabolic stability of DAN. To test our hypothesis, nine amino acid prodrugs of DAN were designed and synthesized. Compared with DAN, the optimal prodrug (daidzein-4'-O-CO-N-isoleucine, D-4'-I) demonstrated enhanced water solubility and improved phase II metabolic stability and activation to DAN in plasma. In addition, unlike the passive transport of DAN, D-4'-I maintained high permeability via organic anion-transporting polypeptide 2B1 (OATP2B1)-mediated transport. Importantly, D-4'-I increased the oral bioavailability by 15.5-fold, reduced the gender difference, and extended the linear absorption capacity in the pharmacokinetics of DAN in rats. Furthermore, D-4'-I exhibited dose-dependent protection against liver injury. Thus, the natural amino acid-bearing carbamate prodrug strategy shows potential in increasing water solubility and improving phase II metabolic stability to enhance the oral bioavailability of DAN.


Assuntos
Isoflavonas , Pró-Fármacos , Animais , Ratos , Administração Oral , Aminoácidos/química , Disponibilidade Biológica , Carbamatos/química , Pró-Fármacos/química , Solubilidade , Água
2.
J Hazard Mater ; 448: 130881, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36758434

RESUMO

The copper-peroxy complex (Cu-OOSO3-) metastable intermediate has been confirmed to oxidize contaminants via a single-electron-transfer pathway or an oxygen-atom-transfer pathway. And the effects of Cu oxidation states and reaction pH conditions on the intermediate properties have not been explored in depth. Here, copper oxide (CuOx) catalysts with different Cu oxidation states were synthesized by a simple precipitation method by controlling the reaction temperature from 0 to 45 °C. CuOx displayed a strong catalytic dependence on the Cu oxidation state, and CuOx-30 with Cu average valence on the catalyst surface of 1.61 was more reactive for catalytic degradation of bisphenol A with peroxymonosulfate (PMS). Notably, CuOx-30, with the best electron-accepting ability, was easier to bonding with PMS to form the Cu-OOSO3- reactive complex, and the generated intermediate exhibited the strongest capacity to obtain electrons from contaminants. Moreover, the electron-transfer pathways were closely related to the average valence of Cu, and the contribution of the oxygen-atom-transfer pathway changed volcanic with increasing Cu valence. Meanwhile, the reaction predominantly involved the oxygen-atom-transfer pathway under acidic conditions (pH=3), while the contribution of the single-electron-transfer pathway raised with increasing pH values. Hence, this work was devoted to providing new insights into the CuOx-inducing PMS activation and vital supplementary to the properties of the Cu-OOSO3- intermediate.

3.
J Environ Manage ; 326(Pt A): 116540, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36427360

RESUMO

Aerobic granular sludge (AGS) is a promising technology for engineering applications in the biological treatment of sewage. New objective is to skip the conventional granulation step to integrate it into a continuous-flow reactor directly. This study proposed a method for integrating spherical pelletizing granular sludge (SPGS) into a new patented aerobic granular sludge bed (AGSB), a continuous up-flow reactor. AGSB system could be startup directly, and after 120 days of operation, the SPGS maintained a relatively intact spherical structure and stability. With an initial high chemical oxygen demand (COD) volume loading of over 2.0 kg/(m3·d), this system achieved the desired effect as the same as a mature AGS system. The final mixed liquid suspended solids, and the ratio of 30 min-5 min sludge volume index (SVI30/SVI5) were 20,000 mg/L, and 0.84, respectively. Although hydraulic elution and filamentous bacteria (FBs) had a slightly negative impact on initial phase pollutant removal, the final removal rates for COD, total nitrogen (TN), ammonia nitrogen (NH4+-H), and total phosphorus (TP) were 90%, 70%, 95%, and 85%, respectively. The presence of specific functional microorganisms promoted the secretion of extracellular polymeric substances (EPS), from 90.65 to 209.78 mg/gVSS. The maturation process of SPGS altered the microbial community structures and reduced the species abundance of microbes in sludge.


Assuntos
Nitrogênio , Esgotos , Amônia , Fósforo , Engenharia
4.
Eur Spine J ; 31(11): 2913-2919, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36114324

RESUMO

PURPOSE: Low back pain (LBP) is a common health problem in the global population. This study aims to assess whether smoking initiation, alcohol consumption, and coffee consumption are causally with an increased risk of LBP. METHODS: A two-sample Mendelian Randomization (MR) study was designed, based on summary-level data from the largest published genome-wide association studies. Single nucleotide polymorphisms with genome-wide significance level (P < 5.0 × 10-8) were selected as instrumental variables for each exposure. Standard inverse-variance weighted (IVW) method was used as the primary statistical method. The weighted median, MR-Egger regression, and MR-PRESSO methods, which relax some IV assumptions, were used for sensitivity analysis. RESULTS: Genetically predicted smoking initiation was causally associated with higher odds of LBP. The pooled OR of LBP using IVW method was 1.36 (95%CI 1.22 1.52; P = 6.0 × 10-8) for one SD increase in the prevalence of smoking initiation, which was supported by the weighted median method (OR: 1.41, 95%CI 1.22, 1.64; P = 5.7 × 10-6). Sensitivity analysis confirmed the robustness of pooled OR of LBP. There was no evidence to suggest a causal effect of alcohol and coffee consumption on LBP. The pooled ORs of LBP were 1.36 (95%CI 0.94, 1.97; P = 0.10) for alcohol consumption and 1.00 (95%CI 0.99, 1.00; P = 0.17) for coffee consumption, respectively. CONCLUSION: Smoking is casually associated with an increased risk of LBP. Smoking control should be recommended in LBP patients to avoid worsening the disease. The safety of LBP with moderate alcohol and coffee consumption merits more study.


Assuntos
Estudo de Associação Genômica Ampla , Dor Lombar , Humanos , Café/efeitos adversos , Etanol/efeitos adversos , Dor Lombar/etiologia , Dor Lombar/genética , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Fumar/efeitos adversos , Fumar/epidemiologia
5.
Front Cell Dev Biol ; 10: 838992, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36036003

RESUMO

Oocyte quality is a determinant of a successful pregnancy. The final step of oocyte development is oocyte maturation, which is susceptible to environmental exposures. Aristolochic acids (AAs), widely existing in Aristolochia and Asarum plants that have been used in traditional medicine, can result in a smaller ovary and fewer superovulated oocytes after in vivo exposure to mice. However, whether AAs affect oocyte maturation and the underlying mechanism(s) are unclear. In this study, we focused on the effect of Aristolochic acid I (AAI), a major compound of AAs, on the maturation of in vitro cultured mouse oocytes. We showed that AAI exposure significantly decreased oocyte quality, including elevated aneuploidy, accompanied by aberrant chiasma patterns and spindle organization, and decreased first polar body extrusion and fertilization capability. Moreover, embryo development potential was also dramatically decreased. Further analyses revealed that AAI exposure significantly decreased mitochondrial membrane potential and ATP synthesis and increased the level of reactive oxygen species (ROS), implying impaired mitochondrial function. Insufficient ATP supply can cause aberrant spindle assembly and excessive ROS can cause premature loss of sister chromatid cohesion and thus alterations in chiasma patterns. Both aberrant spindles and changed chiasma patterns can contribute to chromosome misalignment and thus aneuploidy. Therefore, AAI exposure decreases oocyte quality probably via impairing mitochondrial function.

6.
J Environ Manage ; 318: 115595, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35772268

RESUMO

Intimate coupling of photocatalysis and biodegradation (ICPB) is considered a promising approach for the degradation of recalcitrant organic compounds. In this work, using Trichoderma with benzene degradation ability coupled with activated sludge as a biological source and sugarcane bagasse cellulose composite as a carrier, the ICPB system showed excellent degradation and mineralization of trichlorobenzene under visible light induction. The biofilm inside the ICPB carrier can degrade and mineralize the photocatalytic products. ICPB increased the degradation efficiency of 1,2,3-TCB and 1,3,5-TCB by 12.43% and 4.67%, respectively, compared to photocatalysis alone. The biofilms inside the ICPB carriers can mineralize photocatalytic products, which increases the mineralization efficiency by 18.74%. According to the analysis of intermediates, the degradation of 1,2,3-TCB in this coupled system involved stepwise dechlorination and ring opening. The biofilm in ICPB carrier evolved to be enriched in Cutaneotrichosporon, Trichoderma, Apiotrichum, Zoogloea, Dechloromonas, Flavihumibacter and Cupriavidus, which are known for biodegradable aromatic hydrocarbon and halogenate. Novel microbial seeds supplemented with Trichoderma-based ICPB seem to provide a new potential strategy for effective degradation and mineralization of TCB.


Assuntos
Celulose , Saccharum , Bactérias/metabolismo , Biodegradação Ambiental , Celulose/metabolismo , Clorobenzenos , Titânio
7.
J Biol Chem ; 294(47): 17863-17874, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31624145

RESUMO

Long noncoding RNAs (lncRNAs) modulate gene expression as competing endogenous RNAs (ceRNAs) that sponge regulatory microRNAs (miRNAs). During cellular reprogramming, genes associated with pluripotency establishment need to be up-regulated, and developmental genes need to be silenced. However, how ceRNAs control cellular reprogramming still awaits full elucidation. Here, we used doxycycline-inducible expression of the four transcription factors octamer-binding protein 4 (OCT4), SRY-box 2 (SOX2), Krüppel-like factor 4 (KLF4), and proto-oncogene c-Myc (c-Myc) to generate induced pluripotent stem cells (iPSCs) from mouse embryonic fibroblasts (MEFs). Using RNA-Seq and bioinformatics approaches, we found that the expression levels of miRNAs from MEFs remain high from day 0 to 6 after the doxycycline induction. Many genes targeted by these miRNAs were up-regulated, and long intergenic noncoding RNAs (lincRNAs) and circular RNAs (circRNAs), which have complementary binding sites to these miRNAs, were highly expressed, indicating lincRNAs and circRNAs may function as ceRNAs. Intriguingly, knockdown of the linc/circRNAs that sponge the miRNAs, which target OCT4 down-regulated exogenous OCT4, decreased reprogramming efficiency, and resulted in low-grade iPSCs. Our results suggest that the ceRNA network plays an important role in cellular reprogramming.


Assuntos
Reprogramação Celular/genética , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Fator 3 de Transcrição de Octâmero/genética , RNA Longo não Codificante/metabolismo , Animais , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 4 Semelhante a Kruppel , Camundongos Endogâmicos C57BL , Modelos Biológicos , Fator 3 de Transcrição de Octâmero/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , RNA Longo não Codificante/genética
8.
J Genet ; 982019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30945695

RESUMO

Ionizing radiations (IRs) are widespread damaging stresses to plant growth and development. However, the regulatory networks underlying the mechanisms of responses to IRs remains poorly understood. Here, a set of publicly available transcriptomic data (conducted by Van Hoeck et al. 2015a), in which Lemna minor plants were exposed to a series of doses of gamma, beta and uranium treatments was used to perform gene coexpression network analysis. Overall, the genes involved in DNA synthesis and chromatin structure, light signalling, photosynthesis, and carbohydrate metabolism were commonly responsive to gamma, beta and uranium treatments. Genes related to anthocyanin accumulation and trichome differentiation were specifically downregulated, andgenes related to nitrogen and phosphate nutrition, cell vesicle transport, mitochondrial electron transport and ATP synthesis were specifically upregulated in response to uranium treatment. While genes involved in DNA damage and repair, RNA processing and RNA binding were specifically downregulated and genes involved in calcium signalling, redox and degradation of carbohydrate metabolism were specifically upregulated responding to gamma radiation. These findings revealed both dose-dependent and typespecific networks responding to different IRs in L. minor, and can be served as a useful resource to better understand the mechanisms of responses to different IRs in other plants.


Assuntos
Araceae/genética , Araceae/efeitos da radiação , Bases de Dados Factuais , Raios gama , Redes Reguladoras de Genes/efeitos da radiação , Proteínas de Plantas/genética , Urânio , Araceae/crescimento & desenvolvimento , Partículas beta , Relação Dose-Resposta à Radiação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Análise de Sequência de RNA , Transcriptoma
10.
Mater Sci Eng C Mater Biol Appl ; 69: 12-6, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612683

RESUMO

Nanoparticle mediated photothermal ablation of cancerous tissue shows promising results and applicability as a highly efficacious treatment method. As a majority of the photothermal work has been conducted with minimal attenuation of the laser before reaching the nanoparticles within surface seeded tumors in-vivo or through buffered media in-vitro, it is important to understand the effects of greater laser attenuation on photothermal efficacy mediated by changes in the scattering and absorption of the laser. Photothermal efficacy using a near infrared (NIR) 785nm laser irradiating polystyrene (PS) stabilized magnetite (Fe3O4) nanoparticles (PS-Fe3O4) is examined on MDA-MB-231 human mammary gland adenocarcinoma in-vitro. Agarose gel columns of various heights were created to simulate soft tissue and subsequently used for NIR laser attenuation. Polystyrene was found to significantly improve magnetite nanoparticle stability in serum containing media and modified Hank's Balanced Salt Solution and was able to induce significant hyperthermic ablation at mass concentrations which also did not elicit significant innate toxicity. Furthermore it was found that the polystyrene coating significantly reduced innate toxicity over 48h compared to uncoated magnetite. Agar gel layers provided similar optical attenuation in the NIR region to skin and prostate.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Meios de Cultura , Feminino , Óxido Ferroso-Férrico/química , Humanos , Raios Infravermelhos , Lasers , Nanopartículas de Magnetita/toxicidade , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Poliestirenos/química
11.
Int J Mol Sci ; 17(2): 262, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26907263

RESUMO

Myrosinases are ß-thioglucoside glucohydrolases and serve as defense mechanisms against insect pests and pathogens by producing toxic compounds. AtTGG6 in Arabidopsis thaliana was previously reported to be a myrosinase pseudogene but specifically expressed in pollen. However, we found that AlTGG6, an ortholog to AtTGG6 in A. lyrata (an outcrossing relative of A. thaliana) was functional, suggesting that functional AtTGG6 alleles may still exist in A. thaliana. AtTGG6 alleles in 29 A. thaliana ecotypes were cloned and sequenced. Results indicate that ten alleles were functional and encoded Myr II type myrosinase of 512 amino acids, and myrosinase activity was confirmed by overexpressing AtTGG6 in Pichia pastoris. However, the 19 other ecotypes had disabled alleles with highly polymorphic frame-shift mutations and diversified sequences. Thirteen frame-shift mutation types were identified, which occurred independently many times in the evolutionary history within a few thousand years. The functional allele was expressed specifically in pollen similar to the disabled alleles but at a higher expression level, suggesting its role in defense of pollen against insect pests such as pollen beetles. However, the defense function may have become less critical after A. thaliana evolved to self-fertilization, and thus resulted in loss of function in most ecotypes.


Assuntos
Arabidopsis/genética , Genes de Plantas , Pólen/genética , Pseudogenes , Alelos , Arabidopsis/enzimologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Clonagem Molecular , Evolução Molecular , Mutação da Fase de Leitura , Regulação da Expressão Gênica de Plantas , Glicosídeo Hidrolases/genética , Especificidade de Órgãos , Filogenia , Pólen/enzimologia , Análise de Sequência de DNA
12.
Mater Sci Eng C Mater Biol Appl ; 46: 97-102, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25491964

RESUMO

The photothermal effect of magnetite (Fe3O4) nanoparticles was characterized by photonic absorption in the near-infrared (NIR) region. Upon laser irradiation at 785 nm, the Fe3O4 nanoparticles generate localized hyperthermia in tumorous lesions, which is an effective strategy for cancer therapy; however, uncoated magnetite possesses an innate toxicity which can lead to drawbacks in the clinical setting. To reduce innate toxicity, a poly(acrylic acid) (PAA) coating on the nanoparticles was investigated in order to determine the alterations to stability and the degree of toxicity in an attempt to create a higher utility vector. It was found that the PAA coating significantly reduced the innate toxicity of the uncoated magnetite. Furthermore, the efficacy of PAA-coated magnetite nanoparticles (PAA-Fe3O4) was investigated for treating MDA-MB-231 (human mammary gland adenocarcinoma) cultures in viable concentration ranges (0.1-0.5mg/ml). An appropriate PAA-Fe3O4 concentration range was then established for inducing significant cell death by hyperthermic ablation, but not through innate toxicity.


Assuntos
Resinas Acrílicas/química , Antineoplásicos/química , Materiais Biocompatíveis/química , Raios Infravermelhos , Nanopartículas de Magnetita/química , Fototerapia , Antineoplásicos/toxicidade , Materiais Biocompatíveis/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lasers , Nanopartículas de Magnetita/toxicidade , Neoplasias/terapia
13.
Phys Chem Chem Phys ; 14(35): 12295-300, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22858872

RESUMO

Bulk ZrO(2) polymorphs generally have an extremely high amorphization tolerance upon low energy ion and swift heavy ion irradiation in which ballistic interaction and ionization radiation dominate the ion-solid interaction, respectively. However, under very high-energy irradiation by 1.33 GeV U-238, nanocrystalline (40-50 nm) monoclinic ZrO(2) can be amorphized. A computational simulation based on a thermal spike model reveals that the strong ionizing radiation from swift heavy ions with a very high electronic energy loss of 52.2 keV nm(-1) can induce transient zones with temperatures well above the ZrO(2) melting point. The extreme electronic energy loss, coupled with the high energy state of the nanostructured materials and a high thermal confinement due to the less effective heat transport within the transient hot zone, may eventually be responsible for the ionizing radiation-induced amorphization without transforming to the tetragonal polymorph. The amorphization of nanocrystalline zirconia was also confirmed by 1.69 GeV Au ion irradiation with the electronic energy loss of 40 keV nm(-1). These results suggest that highly radiation tolerant materials in bulk forms, such as ZrO(2), may be radiation sensitive with the reduced length scale down to the nano-metered regime upon irradiation above a threshold value of electronic energy loss.


Assuntos
Ouro/química , Íons Pesados , Nanoestruturas/química , Urânio/química , Zircônio/química , Cristalização
14.
Zhongguo Zhong Yao Za Zhi ; 35(21): 2838-41, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21322943

RESUMO

OBJECTIVE: To establish RP-HPLC method for determination of atropine sulphate, diphenhydramine hydrochloride, capsaicin and dihydrocapsaicin in pain-relieving plaster for arthritis. METHOD: The sample were separated on an Alltima C18 Column (4.6 mm x 250 mm, 5 microm) with the moblie phase of CH3 CN-0.1% H3 PO4. Flow rate was 1 mL x min(-1). The detective wavelength was set at 210 and 280 nm. Column temperature was 30 degrees C. RESULT: The calibration curve for atropine sulphate, diphenhydramine hydrochloride, capsaicin and dihydrocapsaicin revealed linearity in the range of 2.01-50.25, 15.08-377.00, 5.02-125.50, 5.03-125.75 mg x L(-1), respectively. The recoveries of atropine sulphate, diphenhydramine hydrochloride, capsaicin and dihydrocapsaicin were 99.00% with RSD of 0.95%, 99.89% with RSD of 1.2%, 100.1% with RSD of 1.5% and 99.51%, with RSD of 1.4%, respectively. CONCLUSION: The method is simple, rapid and accurate, which is suitable for the quality control of pain-relieving plaster for arthritis.


Assuntos
Artrite/tratamento farmacológico , Atropina/análise , Capsaicina/análogos & derivados , Capsaicina/análise , Cromatografia Líquida de Alta Pressão/métodos , Difenidramina/análise , Medicamentos de Ervas Chinesas/análise , Dor/tratamento farmacológico , Atropina/uso terapêutico , Capsaicina/uso terapêutico , Difenidramina/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos
15.
Phytochemistry ; 70(11-12): 1345-54, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19703694

RESUMO

Myrosinases (EC 3.2.1.147) are beta-thioglucoside glucosidases present in Brassicaceae plants. These enzymes serve to protect plants against pathogens and insect pests by initiating breakdown of the secondary metabolites glucosinolates into toxic products. Several forms of myrosinases are present in plants but the properties and role of different isoenzymes are not well understood. The dicot plant model organism Arabidopsis thaliana seems to contain six myrosinase genes (TGG1-TGG6). In order to compare the different myrosinases, cDNAs corresponding to TGG1 from leaves and TGG4 and TGG5 from roots were cloned and overexpressed in Pichia pastoris. The His-tagged recombinant proteins were purified using affinity chromatography and the preparations were homogenous according to SDS-PAGE analysis. Myrosinase activity was confirmed for all forms and compared with respect to catalytic activity towards the allyl-glucosinolate sinigrin. There was a 22-fold difference in basal activity among the myrosinases. The enzymes were active in a broad pH range, are rather thermostable and active in a wide range of salt concentrations but sensitive to high salt concentrations. The myrosinases showed different activation-inhibition responses towards ascorbic acid with maximal activity around 0.7-1 mM. No activity was registered towards desulphosinigrin and this compound did not inhibit myrosinase activity towards sinigrin. All myrosinases also displayed O-beta-glucosidase activity, although with lower efficiency compared to the myrosinase activity. The differences in catalytic properties among myrosinase isozymes for function in planta are discussed.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Genes de Plantas , Glicosídeo Hidrolases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Ácido Ascórbico/metabolismo , Catálise , DNA Complementar , Glucosinolatos/metabolismo , Glicosídeo Hidrolases/genética , Concentração de Íons de Hidrogênio , Isoenzimas , Pichia/genética , Pichia/metabolismo , Folhas de Planta/enzimologia , Folhas de Planta/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sais , Temperatura , beta-Glucosidase/metabolismo
16.
J Neurophysiol ; 99(5): 2736-40, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18385479

RESUMO

Voltage-gated KCNQ potassium channels are responsible for slowly activating potassium currents in heart, brain, and other tissues. Functional defects of KCNQ channels are linked with many diseases, including epilepsy and cardiac arrhythmias. Therefore KCNQ potassium channels have been widely studied, especially in the CNS. We have identified Drosophila CG11963, which encodes a protein orthologous to the beta subunit of mammalian succinyl-CoA synthetase (SCS, also known as succinate thiokinase), as a novel modulator of Drosophila KCNQ channels. Direct interaction of CG11963 and dKCNQ was demonstrated by yeast two-hybrid screen and coimmunoprecipitation. Cell surface biotinylation experiments further confirmed that CG11963 resides on the plasma membrane of tsA-201 cells. Coexpression of CG11963 with dKCNQ shifts the conductance-voltage (G-V) relationship of dKCNQ channels to more positive membrane potentials in Chinese hamster ovary (CHO) cells. Moreover, directly dialyzing glutathione S-transferase fusion CG11963 protein into CHO cells also shifts the dKCNQ G-V curve rightward. The effect of CG11963 persists in the presence of 1 mM adenosine triphosphate (ATP), a substrate of SCS. Taken together, our data define CG11963 as a new dKCNQ-binding protein capable of modulating the properties of the channel. Our evidence suggests that this modulation is mediated by direct interaction of CG11963 with the channel and is not dependent on ATP.


Assuntos
Proteínas de Drosophila/fisiologia , Drosophila/fisiologia , Canais de Potássio KCNQ/fisiologia , Succinato-CoA Ligases/fisiologia , Trifosfato de Adenosina/fisiologia , Sequência de Aminoácidos , Animais , Biotinilação , Células CHO , Clonagem Molecular , Cricetinae , Cricetulus , DNA Complementar/biossíntese , DNA Complementar/genética , Eletrofisiologia , Glutationa Transferase/metabolismo , Dados de Sequência Molecular , Técnicas de Patch-Clamp
17.
Zhongguo Zhong Yao Za Zhi ; 27(11): 838-40, 2002 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12776588

RESUMO

OBJECTIVE: To develop the quality control standard of Zhishidaozhi Tabloid Pills. METHOD: Applying TLC to identify Radix et Rhizoma Rhei, Fructus Aurantii Immaturus, Rhizoma Coptidis, Radix Scutellariae, and HPLC to determine the content of emodin of Radix et Rhizoma Rhei. RESULT: Radix et Rhizoma Rhei, Fructus Aurantii Immaturus, Rhizoma Coptidis and Radix Scutellariae could be indentified by TLC. Emodin showed a good linear relationship at a rang of 0.0612-0.612 microgram, r = 0.9999. The average recovery was 97.9%, and RSD was 2.1%. CONCLUSION: The methods are accurate and quick, and can be used for the quality control of Zhishidaozhi Tabloid Pills.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/normas , Emodina/análise , Plantas Medicinais , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Citrus/química , Coptis/química , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Frutas/química , Raízes de Plantas/química , Plantas Medicinais/química , Controle de Qualidade , Rheum/química , Rizoma/química , Scutellaria/química
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