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1.
Sensors (Basel) ; 23(17)2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37687962

RESUMEN

Mobile sensors can extend the range of monitoring and overcome static sensors' limitations and are increasingly used in real-life applications. Since there can be significant errors in mobile sensor localization using the Monte Carlo Localization (MCL), this paper improves the food digestion algorithm (FDA). This paper applies the improved algorithm to the mobile sensor localization problem to reduce localization errors and improve localization accuracy. Firstly, this paper proposes three inter-group communication strategies to speed up the convergence of the algorithm based on the topology that exists between groups. Finally, the improved algorithm is applied to the mobile sensor localization problem, reducing the localization error and achieving good localization results.

2.
Zhongguo Zhong Yao Za Zhi ; 45(23): 5701-5711, 2020 Dec.
Artículo en Zh | MEDLINE | ID: mdl-33496110

RESUMEN

This study is to improve the quality standard and supply the scientific basis for Anemarrhenae Rhizoma and its raw processed products. Steroidal saponin including timosaponin BⅡ, timosaponin AⅢ and flavonoids including neomangiferin and mangiferin were selected as the indicative components. Silica gel G thin layer chromatography(TLC) and polyamide TLC were used to detect the two types of compounds, respectively. The contents of timosaponin BⅡ and timosaponin AⅢ were determined by HPLC-ELSD and the content of neomangiferin, mangiferin and isomangiferin were determined by HPLC-UV. Moisture, total ash and acid insoluble ash were determined according to Chinese Pharmacopoeia(2015 edition). And 80% ethanol was selected as the solvent and the content determination of total extract were determined. The fingerprints of Anemarrhenae Rhizoma and its raw processed products were established by HPLC-UV and HPLC-ELSD. The results showed that the methods of TLC and HPLC have been successfully stablished. There are 2 and 3 peaks which have been identified by HPLC-ELSD and HPLC-UV, respectively. The HPLC fingerprint methods are specific and can be used to identify and quality control for Anemarrhenae Rhizoma and its raw processed products in the mass. Comparing to Chinese Pharmacopoeia(2015 edition), the TLC identification and content determination were revised and the total extract determination and HPLC fingerprints were added in the present study. Our results can be used as the scientific basis of quqlity control for Anemarrhenae Rhizoma and its raw processed products.


Asunto(s)
Anemarrhena , Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Estándares de Referencia , Rizoma
3.
Bioorg Med Chem Lett ; 27(2): 342-346, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27899265

RESUMEN

DNA methyltransferases are involved in diverse biological processes and abnormal methylation patterns play essential roles in cancer initiation and progression. DNA methyltransferase 3A (DNMT3A) acting as a de novo DNA methyltransferase, has gained widespread attention especially in haematological diseases. To date, large numbers of DNMTs inhibitors have been discovered, however, the small molecular inhibitors targeting DNMT3A are still in its infancy. In this study, structure-based virtual screening in combination with biological assays was performed to discovery potent novel DNMT3A inhibitors. Compound 40 and 40_3 displayed comparable in vitro inhibitory activity against DNMT3A with IC50 values of 46.5µM and 41µM, respectively. Further binding mode analysis suggested these molecules inhibit DNMT3A activity through binding the S-adenosyl-l-methionine (SAM) pocket. Overall, 40 and 40_3 may serve as novel scaffolds for further optimization and small molecular probes for investigating DNMT3A function.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Línea Celular , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN Metiltransferasa 3A , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad
4.
Front Microbiol ; 15: 1301204, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38591032

RESUMEN

Introduction: Mycobacterium tuberculosis (Mtb), the main cause of tuberculosis (TB), has brought a great burden to the world's public health. With the widespread use of Mtb drug-resistant strains, the pressure on anti-TB treatment is increasing. Anti-TB drugs with novel structures and targets are urgently needed. Previous studies have revealed a series of CYPs with important roles in the survival and metabolism of Mtb. However, there is little research on the structure and function of CYP138. Methods: In our study, to discover the function and targetability of CYP138, a cyp138-knockout strain was built, and the function of CYP138 was speculated by the comparison between cyp138-knockout and wild-type strains through growth curves, growth status under different carbon sources, infection curves, SEM, MIC tests, quantitative proteomics, and lipidomics. Results and discussion: The knockout of cyp138 was proven to affect the Mtb's macrophage infection, antibiotics susceptibility, and the levels of fatty acid metabolism, membrane-related proteins, and lipids such as triacylglycerol. We proposed that CYP138 plays an important role in the synthesis and decomposition of lipids related to the cell membrane structure as a new potential anti-tuberculosis drug target.

5.
Bioresour Technol ; 351: 127026, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35314309

RESUMEN

Dissimilatory sulfate reduction (DSR) in cake layer of full-scale anaerobic dynamic membrane bioreactor for treating hotel laundry wastewater was studied. Change (Δ) of sulfate concentration (ΔSO42-) was positively correlated to dynamic cake layer (DCL) development, while ΔS2- was negatively correlated. ΔSO32- and ΔSorganic sulfur remained around 1.5-2.5 and 1.2-2.3 mg-S/L, respectively. Thus, DSR was the predominant sulfate reduction process in DCL. 33 binned genomes from DCL microbiome samples possessed one or more DSR functional genes. But only four binned genomes possess all functional genes, and thus can achieve complete DSR. However, no significant variations of these DSR bacteria was obseared during DCL development. Metagenomic analysis predicted that sulfate reduction in DCL was mainly carried out by collaborations between bacteria with incomplete DSR pathways. Among which, sulfite â†’ sulfide by dissimilatory-sulfite-reductase expression bacteria was the key process. Overall results suggested that controlling dissimilatory-sulfite-reductase activities could prevent sulfide buildup in the effluent.


Asunto(s)
Reactores Biológicos , Aguas Residuales , Anaerobiosis , Bacterias/genética , Bacterias/metabolismo , Oxidación-Reducción , Oxidorreductasas/metabolismo , Sulfatos/metabolismo , Sulfuros/metabolismo , Sulfitos
6.
Chemosphere ; 307(Pt 4): 136078, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35985382

RESUMEN

Identification of dissimilatory nitrate reduction to ammonium (DNRA) and denitrification in the dynamic cake layer of a full-scale anoixc dynamic membrane bioreactor (AnDMBR) for treating hotel laundry wastewater was studied. A series of experiments were conducted to understand the contributions of DNRA and canonical denitrification activities in the dynamic cake layer of the AnDMBR. The dynamic cake layer developed included two phases - a steady transmembrane pressure (TMP) increase at 0.24 kPa/day followed by a sharp TMP jump at 1.26 kPa/day four to five days after the AnDMBR start-up. The nitrogen mass balance results showed that canonical denitrification was predominant during the development of the dynamic cake layer. However, DNRA activity and accumulation of bacteria equipped with a complete DNRA pathway showed a positive correlation to the development of the dynamic cake layer. Our metagenomic analysis identified an approximately 18% of the dynamic cake layer bacterial community has a complete DNRA pathway. Pannonibacter (1%), Thauera (0.8%) and Pseudomonas (3%) contained all genes encoding for funcional enzymes of both DNRA (nitrate reductase and DNRA nitrite reductase) and denitrification (nitrate reductase, nitrous oxide reductase and nitric oxide reductase). No other metagenome-assembled genomes (MAGs) possessed a complete cononical denitrification pathway, indicating food-chain-like interactions of denitrifiers in the dynamic cake layer. We found that COD loading rate could be used to control DNRA and canonical denitrification activities during the dynamic cake layer formation.


Asunto(s)
Compuestos de Amonio , Compuestos de Amonio/metabolismo , Bacterias/genética , Bacterias/metabolismo , Reactores Biológicos , Desnitrificación , Nitratos/análisis , Nitrito Reductasas/metabolismo , Nitrógeno/metabolismo , Óxidos de Nitrógeno , Compuestos Orgánicos , Oxidación-Reducción , Aguas Residuales
7.
Cell Rep Med ; 3(6): 100660, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35732156

RESUMEN

Glucocorticoid-induced tumor necrosis factor receptor (GITR) is a co-stimulatory receptor and an important target for cancer immunotherapy. We herein present a potent FcγR-independent GITR agonist IBI37G5 that can effectively activate effector T cells and synergize with anti-programmed death 1 (PD1) antibody to eradicate established tumors. IBI37G5 depends on both antibody bivalency and GITR homo-dimerization for efficient receptor cross-linking. Functional analyses reveal bell-shaped dose responses due to the unique 2:2 antibody-receptor stoichiometry required for GITR activation. Antibody self-competition is observed after concentration exceeded that of 100% receptor occupancy (RO), which leads to antibody monovalent binding and loss of activity. Retrospective pharmacokinetics/pharmacodynamics analysis demonstrates that the maximal efficacy is achieved at medium doses with drug exposure near saturating GITR occupancy during the dosing cycle. Finally, we propose an alternative dose-finding strategy that does not rely on the traditional maximal tolerated dose (MTD)-based paradigm but instead on utilizing the RO-function relations as biomarker to guide the clinical translation of GITR and similar co-stimulatory agonists.


Asunto(s)
Glucocorticoides , Receptores de IgG , Línea Celular Tumoral , Proteína Relacionada con TNFR Inducida por Glucocorticoide/agonistas , Ligandos , Receptores del Factor de Necrosis Tumoral/agonistas , Estudios Retrospectivos , Factores de Necrosis Tumoral
8.
Sci Total Environ ; 780: 146600, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33774305

RESUMEN

Phosphogypsum (PG) is an industry solid waste produced from phosphoric acid manufacture. To reduce environmental pollution of the PG, H2C2O4 was employed to purify it, which then can be used for cement production. The optimal concentration of H2C2O4 for PG purification was determined. In addition, differential thermal analysis (DTA), X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence (XRF) were used to determine the removal of phosphate impurity in PG. The effects of purified PG on cement hydration and the environmental implications were also investigated. The results demonstrate that H2C2O4 can remove the intercrystalline phosphate impurities by destroying the part of the crystal structure of gypsum. With the best treatment concentration of 1% H2C2O4, 77.7% of phosphate impurity (as P2O5) was removed from PG, which subsequently shortened the final setting time down to 220 min and successfully met the national standard (GB 175-1999). Portland cement prepared by the 1% H2C2O4 treated PG possessed a comparable 3d compressive strength of 20.8 MPa and a 28d compressive strength of 44.6 MPa. It is concluded that PG purified by 1% H2C2O4 treatment can be used for cement production. Meanwhile, this H2C2O4 treatment can effectively reduce the environmental pollution from PG and offer a sustainable method for the utilization of PG.

9.
ACS Chem Biol ; 13(3): 772-781, 2018 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-29381856

RESUMEN

DNA methyltransferase-1 (DNMT1) plays a crucial role in the maintenance of genomic methylation patterns. The crystal structure of DNMT1 was determined in two different states in which the helix that follows the catalytic loop was either kinked (designated helix-kinked) or well folded (designated helix-straight state). Here, we show that the proper structural transition between these two states is required for DNMT1 activity. The mutations of N1248A and R1279D, which did not affect interactions between DNMT1 and substrates or cofactors, allosterically reduced enzymatic activities in vitro by decreasing kcat/ Km for AdoMet. The crystallographic data combined with molecular dynamic (MD) simulations indicated that the N1248A and R1279D mutants bias the catalytic helix to either the kinked or straight conformation. In addition, genetic complementation assays for the two mutants suggested that disturbing the conformational transition reduced DNMT1 activity in cells, which could act additively with existing DNMT inhibitors to decrease DNA methylation. Collectively, our studies provide molecular insights into conformational changes of the catalytic helix, which is essential for DNMT1 catalytic activity, and thus aid in better understanding the relationship between DNMT1 dynamic switching and enzymatic activity.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasa 1/química , Simulación de Dinámica Molecular , Animales , Dominio Catalítico , Cristalografía por Rayos X , ADN (Citosina-5-)-Metiltransferasa 1/genética , Metilación de ADN/genética , Humanos , Mutación , Conformación Proteica
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