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1.
J Agric Food Chem ; 70(24): 7547-7565, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35687111

RESUMEN

This study aimed to investigate the synergistic bactericidal activity and mechanism of dual-stage light-guided membrane and DNA-targeted photodynamic inactivation (PDI) by the combination of blue light (BL, 420 nm) and the food additive octyl gallate (OG) against Vibrio parahaemolyticus in planktonic and biofilm growth modes. While OG serves as an outstanding exogenous photosensitizer, the planktonic cells were not visibly detectable after the OG-mediated PDI treatment with 0.2 mM OG within 15 min (191.7 J/cm2), and its biofilm was nearly eradicated within 60 min (383.4 J/cm2). Gram-positive Staphylococcus aureus was more susceptible to the PDI than Gram-negative V. parahaemolyticus. The cellular wall and proteins, as well as DNA, were the vulnerable targets for PDI. The membrane integrity could be initially disrupted by OG bearing a hydrophilic head and a hydrophobic tail via transmembrane insertion. The enhancement of OG uptake due to the first-stage light-assisted photochemical internalization (PCI) promoted the accumulation of OG in cells. It further boosted the second-stage light irradiation of the photosensitizer-inducing massive cell death. Upon the second-stage BL irradiation, reactive oxygen species (ROS) generated through the OG-mediated PDI in situ could extensively deconstruct membranes, proteins, and DNA, as well as biofilms, while OG could be activated by BL to carry out photochemical reactions involving the formation of OG-bacterial membrane protein (BMP) covalent conjugates and the interactions with DNA. This dual-stage light-guided subcellular dual-targeted PDI strategy exhibits encouraging effects on the eradication of planktonic bacteria and sessile biofilms, which provides a new insight into the development of an ultraeffective antimicrobial and biofilm removing/reducing technique to improve microbiological safety in the food industry.


Asunto(s)
Fármacos Fotosensibilizantes , Plancton , Bacterias , Biopelículas , ADN , Ácido Gálico/análogos & derivados , Fármacos Fotosensibilizantes/farmacología
2.
J Med Chem ; 65(6): 4709-4726, 2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35254067

RESUMEN

Drug resistance caused by epidermal growth factor receptor (EGFR) mutation has largely limited the clinical use of EGFR tyrosine kinase inhibitors (EGFR-TKIs) for the treatment of non-small-cell lung cancer (NSCLC). Herein, to overcome the intractable problem of drug resistance, proteolysis targeting chimeras (PROTACs) targeting EGFR mutants were developed by optimizing covalent EGFR ligands. Covalent or reversible covalent pyrimidine- or purine-containing PROTACs were designed, synthesized, and evaluated. As a consequence, covalent PROTAC CP17, with a novel purine-containing EGFR ligand, was discovered as a highly potent degrader against EGFRL858R/T790M and EGFRdel19, reaching the lowest DC50 values among all reported EGFR-targeting PROTACs. Furthermore, CP17 exhibited excellent cellular activity against the H1975 and HCC827 cell lines with high selectivity. Mechanism investigation indicated that the lysosome was involved in the degradation process. Importantly, the covalent binding strategy was proven to be an effective approach for the design of PROTACs targeting EGFRL858R/T790M, which laid the practical foundation for further development of potent EGFR-targeting PROTACs.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos , Receptores ErbB , Ligandos , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteolisis , Purinas/farmacología
3.
Ying Yong Sheng Tai Xue Bao ; 33(1): 76-84, 2022 Jan.
Artículo en Chino | MEDLINE | ID: mdl-35224928

RESUMEN

Forest fuels are the basis of fire occurrences, while ground dead fuels are an important part of forest fuels. Undestanding the pyrolysis characteristics and gas emissions of forest fuels is of great significance to explore the effects of forest fire on atmospheric environment and carbon balance, as well as to prevent and combat forest fire. In this study, the thermogravimetric analysis and gas emission analysis were conducted on leaf litter of six tree species (Pinus sylvestris var. mongolica, Picea koraiensis, Fraxinus mandshurica, Juglans mandshurica, Quercus mongolica, Betula platyphylla) in Heilongjiang Province to explore the pyrolysis process and combustibility of forest fuels, to analyze their pyrolysis characteristics, pyrolysis kinetics characteristics, gas emission characteristics. A four-dimensional evaluation of their combustibility was conducted based on pyrolysis parameters. The results showed that the pyrolysis temperature of holocellulose in the leaves of those six tree species ranged in 143.31-180.48 ℃ at the beginning and 345.04-394.38 ℃ at the end, lignin pyrolysis temperature ranged in 345.04-394.38 ℃ at the beginning and 582.85-609.31 ℃ at the end. The pyrolysis of the six kinds of arbor blades during the pyrolysis process affected fuel ash content, quality and temperature of the total pyrolysis. The activation energies of two main pyrolysis stages of leaves of six tree species were 18.88-27.08 kJ·mol-1 and 13.25-27.54 kJ·mol-1, respectively, and the pre-exponential factors were 3.13-26.28 min-1 and 1.30-22.55 min-1. The holocellulose activation energy and pre-exponential factor of the pyrolysis stage for P. koraiensis, F. mandshurica, Q. mongolica, and B. platyphylla were greater than that of the lignin pyrolysis stage, while the opposite was true for P. sylvestris var. mongolica and J. mandshurica. The release amounts of CO and CO2 at the pyrolysis stage of the holocellulose was 535.16-880.11 mg·m-3 and 7004.97-10302.05 mg·m-3, and that at the pyrolysis stage of lignin was 240.31-1104.67 mg·m-3 and 20425.60-33946.68 mg·m-3, respectively. The release of CO and CO2 at the pyrolysis stage of healdellulose was less, but mass loss was greater than that at the pyrolysis stage of lignin. In the four-dimensional combustibility ranking of the six tree species leaves, B. platyphylla was the best ignitable, P. koraiensis was the most combustible, and P. sylvestris var. mongolica was the most sustainable and consumable. The ignitability was significantly positively correlated with pyrolysis kinetics parameters of the holocellulose, while the sustainability was negatively correlated with that of lignin.


Asunto(s)
Pinus , Árboles , China , Bosques , Pirólisis
4.
Chemistry ; 28(4): e202103341, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34773313

RESUMEN

A new class of large-but-flexible Pd-BIAN-NHC catalysts (BIAN=acenaphthoimidazolylidene, NHC=N-heterocyclic carbene) has been rationally designed to enable the challenging Buchwald-Hartwig amination of coordinating heterocycles. This robust class of BIAN-NHC catalysts permits cross-coupling under practical aerobic conditions of a variety of heterocycles with aryl, alkyl, and heteroarylamines, including historically challenging oxazoles and thiazoles as well as electron-deficient heterocycles containing multiple heteroatoms with BIAN-INon (N,N'-bis(2,6-di(4-heptyl)phenyl)-7H-acenaphtho[1,2-d]imidazol-8-ylidene) as the most effective ligand. Studies on the ligand structure and electronic properties of the carbene center are reported. The study should facilitate the discovery of even more active catalyst systems based on the unique BIAN-NHC scaffold.


Asunto(s)
Compuestos Heterocíclicos , Aminación , Catálisis , Ligandos , Paladio
5.
Int J Food Microbiol ; 361: 109460, 2022 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-34785387

RESUMEN

A series of alkyl gallates were evaluated for the antibacterial activity against two common Gram-negative foodborne bacteria (Pseudomonas fluorescens and Vibrio parahaemolyticus) associated with seafood. The length of the alkyl chain plays a pivotal role in eliciting their antibacterial activities and octyl gallate (OG) exerted an excellent inhibitory efficacy. To extend the aqueous solubility, stability, and bactericidal properties of octyl gallate (OG), an inclusion complex between OG and ß-cyclodextrin (ßCD), OG/ßCD, was prepared and identified with various methods including X-ray diffraction (XRD), differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). Furthermore, the enhanced inhibitory effect and potential antibacterial mechanism of OG/ßCD against two Gram-negative and Gram-positive foodborne bacteria were comprehensively investigated. The results show that OG/ßCD could function against bacteria through effectively damaging the membrane, permeating into cells, and then disturbing the activity of the respiratory electron transport chain to cause the production of high-level intracellular hydroxyl radicals. Moreover, the reinforced OG/ßCD-incorporated polylactic acid (PLA) nanofibers were fabricated using the electrospinning technique as food packaging to extend the Chinese giant salamander fillet's shelf life at 4 °C. This research highlights the antibacterial effectiveness of OG/ßCD in aqueous media, which can be used as a safe multi-functionalized food additive combined with the benefits of electrospun nanofibers to extend the Chinese giant salamander fillets shelf life by 15 d at 4 °C.


Asunto(s)
Nanofibras , Pseudomonas fluorescens , Vibrio parahaemolyticus , beta-Ciclodextrinas , Animales , Antibacterianos/farmacología , China , Ácido Gálico/análogos & derivados , Espectroscopía Infrarroja por Transformada de Fourier , Urodelos , beta-Ciclodextrinas/farmacología
6.
Zhongguo Zhong Yao Za Zhi ; 46(21): 5641-5649, 2021 Nov.
Artículo en Chino | MEDLINE | ID: mdl-34951217

RESUMEN

This Radix study cum aims Melle to explore(HRPM)the on efficacy spleen differences deficiency between syndrome.modeling Astragali A Radix of Praeparata110cum rats Melle were(ARPM)randomized fatigue),and into rats Hedysari a Praeparata(n qi total irregular HRPM male diet,SD diarrhea,control were(n Yiqi=10)the=100).Pill group fied and model a modeling group,group Buzhong After(BYP)(through ARPM and the HRPM-H),classimedium-dose into(ARPM-M raised group,and high-dose(ARPM-H each and Rats BYP and under HRPM-M),normal and low-dose and(ARPM-L in and group HRPM-L)were groups,continuously10rats induced.were in group.the in group the were18.9,control given group were g·kg~(-1)conditions while those the the model Rats respectively in18.912.6,BYP kg~(-1)water extract,decoction those in ARPM/HRPM-H,the-M,dosage lasted and of-L groups treated the with control and model6.3group g·rewere motilin determined m L·kg~(-1)·day~(-1).days.of dose Spleen ARPM/HRPM of in water.morning,The at the10Rats spleen in index group thymus and index ceived equal calculated.(MTL),distilled tissue administration to15observe Then the and Routine of each group D-xylose,were was(IL-2),the subjected HE stainingγ(IFN-γ),lower to the pathological changes.(IgA),blood gastric indexes,mucosa index,interleukin-2group.interferon group immunoglobulin of A and spleen pepsin index,of in Ig A,IL-2spleen IFN-γ,control each MTL,levels Rats pepsin the in model(P<0.01),had higher levels routine(P<0.01),blood and indexes,more thymus lesions D-xylose,the and in index,level decreased HRPM-L of IL-2severe compared spleen with than the those model in group.thymus group.that(P<0.05group,P<0.01)index administration thymus groups Ig A or spleen as that and in spleen routine Except index,spleen the Ig A,index,group and were in in ARPM-M model group,group,index,indexes,P<0.01)and thymus MTL index,those in ARPM-L insignificantly Ig A,different pepsin from other those in the the blood index,compared IFN-γ,group,(P<0.05The D-xylose,model MTL,spleen and lesions high-dose in each administration administration groups group increased relieved.blood or comparison as of with HRPM in as the folARPM and the effect in and were white and result than ARPM and is of lows:(P stronger<0.05),of medium-dose high-dose HRPM HRPM on IL-2cell high-dose of(WBC)and count medium-dose the HRPM and corresponding doses than IFN-γmore ARPM the obvious effect(P<0.05of on evident(P<0.05of impact P<0.01),on low-dose between the on corresponD-xylose P<0.01),doses ding MTL doses than Meanwhile,in of or more high-dose,and medium-dose,difference HRPM the and indexes.corresponding there of ARPM in or IL-2no levels in the HRPM-L effect and two groups,on but conclusion,other the both functions IFN-γwas group no was difference more the than recovery that of the and ARPM-H between(IL-2,P<0.01;ARPM-L recovery HRPM the IFN-γ,P<0.05).HRPM-H and obvious therapeutic in rats group qi In ARPM dose have are certain equivalent,effects on with spleen function deficiency.the Specifically,is the better difference immunomodulatory of two at g·low kg~(-1).and but the promote immunomodulatory the of former rats significantly ARPM.than that between of the later two at in the dose>18.9HRPM promotion can of better digestion digestion absorption and may absorption due of than The immunoregulation and be to the difference in clinical medication.


Asunto(s)
Planta del Astrágalo , Medicamentos Herbarios Chinos , Animales , Raíces de Plantas , Ratas , Bazo
7.
J Agric Food Chem ; 69(49): 14961-14974, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34843236

RESUMEN

An excellent bactericidal effect of octyl gallate (OG)-mediated photodynamic inactivation (PDI) against foodborne pathogens (Escherichia coli and Staphylococcus aureus) was evaluated in relation to the mode of action. UV-A irradiation (wavelength, 365 nm; irradiance, 8.254 ± 0.18 mW/cm2) of the bacterial suspension containing 0.15 mM OG could lead to a >5-log reduction of viable cell counts within 30 min for E. coli and only 5 min for S. aureus. Reactive oxygen species (ROS) formation was considered the main reason for the bactericidal effect of OG + UV-A light treatment because toxic ROS induced by OG-mediated PDI could attack the cellular wall, proteins, and DNA of microbes. Moreover, the bactericidal effect, as well as the yields of ROS, depended on OG concentrations, irradiation time, and laser output power. Furthermore, we prepared an edible photodynamic antimicrobial membrane comprising electrospun cyclodextrin nanofibers (NFs) by embedding OG. The resultant OG/HPßCD NFs (273.6 µg/mL) under UV-A irradiation for 30 min (14.58 J/cm) could cause a great reduction (>5-log) of viable bacterial counts of E. coli. The in situ photodynamic antibacterial activity of OG/HPßCD NF-based packaging was evaluated during the Chinese giant salamander storage. Overall, this research highlights the dual functionalities (antibacterial and photodynamic properties) of OG as both an antibacterial agent and photosensitizer and the effectiveness of electrospun NFs containing OG as an active antibacterial packaging material for food preservation upon UV light illumination.


Asunto(s)
Ciclodextrinas , Nanofibras , Escherichia coli , Ácido Gálico/farmacología , Staphylococcus aureus , Rayos Ultravioleta
8.
Anal Cell Pathol (Amst) ; 2021: 6692811, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34194957

RESUMEN

Actin-binding proteins (ABPs), by interacting with actin, regulate the polymerization, depolymerization, bundling, and cross-linking of actin filaments, directly or indirectly, thereby mediating the maintenance of cell morphology, cell movement, and many other biological functions. Consequently, these functions of ABPs help regulate cancer cell invasion and metastasis when cancer occurs. In recent years, a variety of ABPs have been found to be abnormally expressed in various cancers, indicating that the detection and interventions of unusual ABP expression to alter this are available for the treatment of cancer. The early stages of most cancer development involve long-term chronic inflammation or repeated stimulation. This is the case for breast cancer, gastric cancer, lung cancer, prostate cancer, liver cancer, esophageal cancer, pancreatic cancer, melanoma, and colorectal cancer. This article discusses the relationship between chronic inflammation and the above-mentioned cancers, emphatically introduces relevant research on the abnormal expression of ABPs in chronic inflammatory diseases, and reviews research on the expression of different ABPs in the above-mentioned cancers. Furthermore, there is a close relationship between ABP-induced inflammation and cancer. In simple terms, abnormal expression of ABPs contributes to the chronic inflammation developing into cancer. Finally, we provide our viewpoint regarding these unusual ABPs serving as potential biomarkers for chronic inflammation-induced cancer diagnosis and therapy, and interventions to reverse the abnormal expression of ABPs represent a potential approach to preventing or treating the corresponding cancers.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Inflamación/metabolismo , Proteínas de Microfilamentos/metabolismo , Neoplasias/metabolismo , Actinas/metabolismo , Enfermedad Crónica , Citoesqueleto/metabolismo , Progresión de la Enfermedad , Humanos , Inflamación/patología , Neoplasias/diagnóstico , Neoplasias/terapia , Polimerizacion
9.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2691-2698, 2021 Jun.
Artículo en Chino | MEDLINE | ID: mdl-34296565

RESUMEN

Astragali Radix is one of the most commonly used medicinal materials. In recent years, its cultivated varieties and a variety of adulterants have flooded the market, which makes its quality uneven, and the development of quality control methods has become a research hotspot. Therefore, figuring out the quality markers of Astragali Radix is of great significance for its comprehensive evaluation. In this study, the fingerprints of 15 batches of Astragali Radix were established by HPLC, and the main components causing intergroup differences were screened out by PLS-DA. On the basis of literature review and network pharmacology analysis, the targets and pathways of active ingredients were obtained from SwissTargetPrediction, PubChem Compound and other databases, and then the "component-target-pathway" network was constructed with Cytoscape 3.7.1 for the prediction of potential quality markers. Twenty-eight common peaks were identified in the established fingerprint, and three differential components were selected as potential quality markers for Astragali Radix, which were astragaloside Ⅳ, calycosin-7-O-ß-D-glucoside and ononin. The proposed method based on HPLC fingerprint of Astragali Radix is convenient and feasible, facilitating the improvement in its quality control.


Asunto(s)
Planta del Astrágalo , Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Raíces de Plantas , Control de Calidad
10.
J Org Chem ; 85(18): 11750-11765, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32808522

RESUMEN

To pursue a highly regioselective and efficient reductive Heck reaction, a series of moisture- and air-stable α-diimine palladium precatalysts were rationally designed, readily synthesized, and fully characterized. The relationship between the structures of the palladium complexes and the catalytic properties was investigated. It was revealed that the"bulky-yet-flexible"palladium complexes allowed highly anti-Markovnikov-selective hydroarylation of alkenes with (hetero)aryl bromides under aerobic conditions. Further synthetic application of the present protocol could provide rapid and straightforward access to functional and biologically active molecules.

11.
Nanomaterials (Basel) ; 9(7)2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31261670

RESUMEN

With the developments in high-performance nano-insulation material technology, theoretical studies on the heat transfer mechanisms in these materials have been conducted. However, the conductivity of nanometer-sized skeletons is still unclear. It is necessary to clarify the thermal conductivity of nanometer-sized solid skeletons in order to better understand the heat transfer mechanisms in nano-insulation materials. In the present study, a theoretical model for the thermal conductivity of nanometer-sized skeletons in nano-insulation materials is presented based upon the meso-structure of the material and the equation of phonon transfer. The size effect in thermal conductivity of the nanometer-sized particles is studied numerically, and the thermal conductivity is theoretically obtained. At the same time, a reverse method is established for the thermal conductivity of nanometer-sized particles based on the method of particle swarm optimization (PSO). The skeleton thermal conductivity for a specific nano-insulation material with a density of 110 kg/m3 and porosity of 0.94 is identified based upon experimental data from literature. Comparison results show that the theoretical conductivity of nanometer-sized skeletons and the identified results give the values of 0.145 and 0.124 W/(m K), respectively, clearly revealing obvious an size effect in the thermal conductivity of nanometer-sized skeletons.

12.
J Ethnopharmacol ; 238: 111813, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-30910578

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Whitmania pigra Whitman (Whitmania pigra, WP), firstly recorded in the Shennong's Herbal Classic and officially listed in the Chinese Pharmacopoeia, is a well-used cardiovascular protective traditional Chinese medicine derived from leeches. Traditional Chinese physicians prefer to prescribe the dried whole body of leech processed under high temperatures. It has been reported that dried WP remains clinically effective. However, the therapeutic mechanism has yet not be clearly elucidated. AIM OF THE STUDY: This study was designed to investigate the protective activity of the extract of WP in a high-molecular-weight dextran-induced blood hyperviscosity rat model, and to explore the role of WP in improving blood hyperviscosity related metabolic disorders and to clarify the possible mechanism of metabolic regulation. MATERIALS AND METHODS: The hemorheological parameters were measured with an automated blood rheology analyzer. Hematoxylin-eosin staining was used to observe the pathological changes in aortic tissues samples. Further, a liquid chromatography-mass-spectrometry (LC-MS)-based untargeted metabolomics approach was applied to characterize the metabolic alterations. RESULTS: WP has evident attenuating effects on blood hyperviscosity and related metabolic disorders, and the influences are distinct from those of aspirin. The results showed that WP had good effects in reducing blood viscosity and ameliorating histopathological changes in the thoracic aorta in a high molecular weight dextran-induced blood hyperviscosity rat model. The middle dose (2.5 g raw material/kg body weight) of WP exhibited effects equivalent to aspirin (100 mg/kg) on hemorheological and histopathological parameters (P > 0.05). However, when using metabolomics profiling, we found that WP could significantly improve blood hyperviscosity-related metabolic disorders and restore metabolites to normal levels; while aspirin showed little effect. With principal component analysis and orthogonal partial least-squares discriminant analysis, WP regulated many more endogenous metabolites than aspirin. With pathway enrichment analysis, the differential endogenous metabolites were involved in cysteine and methionine metabolism, TCA cycle, arachidonic acid metabolism, etc., highlighting the metabolic reprogramming potential of WP against blood hyperviscosity-induced metabolic disorders. CONCLUSIONS: The study suggest that WP has a more potent effect, but a different mechanism, than aspirin in improving either blood hyperviscosity or related metabolic disorders associated with cardio- and cerebrovascular diseases.


Asunto(s)
Viscosidad Sanguínea/efectos de los fármacos , Mezclas Complejas/farmacología , Sanguijuelas , Animales , Ciclooxigenasa 2/genética , Cistationina betasintasa/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Polvos , Ratas Sprague-Dawley
13.
Zhongguo Zhong Yao Za Zhi ; 43(13): 2720-2725, 2018 Jul.
Artículo en Chino | MEDLINE | ID: mdl-30111022

RESUMEN

Standard decoction of traditional Chinese medicine (TCM) is prepared by standardized process, and can be used as references to evaluate the quality of dosage forms such as decoction and dispensing granules. In order to determine the quality evaluation method for standard decoction of Chrysanthemi Flos and investigate its application, 10 batches of white chrysanthemum of Hangzhou were collected to prepare the standard decoction of white chrysanthemum of Hangzhou with standardized process parameters. Parameters such as traits, relative density, pH value, extraction ratio, transfer rate and fingerprint were selected as the indexes for quality evaluation. The established quality evaluation method for standard decoction of Chrysanthemi Flos was applied in the detection of two types of commercial Chrysanthemum dispensing granules. The results showed that the standard decoction of Chrysanthemi Flos was a clear yellow-brown aqueous solution; the relative density was 1.007-1.011; the pH value was between 5.37-5.56; the average extraction ratio was 23.6%, ranging from 19.93% to 29.69%; the average transfer ratewas 56.2% in terms of chlorogenic acid, 57.4% in terms of luteoloside and 30.6% in terms of 3,5-O-dicaffeoylquinic acid. Fingerprint similarity was between 0.864-0.989.The method showed good precision, stability and repeatability in fingerprint analysis, indicating reliable and representative results for standard decoction of Chrysanthemi Flos, and it can be used to evaluate and standardize other dosage forms.


Asunto(s)
Chrysanthemum , Medicamentos Herbarios Chinos , Ácido Clorogénico , Flores , Medicina Tradicional China
14.
Molecules ; 23(2)2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29443913

RESUMEN

In acidic media, cationic phthalocyanine Alcian blue 8GX, has an efficient fluorescence quenching effect on anionic phthalocyanine tetrasulphoaluminium phthalocyanines (AlS4Pc), forming an almost non-fluorescent associate. Based on this discovery, a red-emitting fluorescent probe consisted of AlS4PC and Alcian blue 8GX has been developed through molecular assembly. Further studies indicated that the presence of Hg(II) ion has a significant fluorescence recovery effect of the probe. Notably, only Hg(II) can significantly restore the fluorescence of AlS4Pc-Alcian blue 8GX system which was revealed from the screening experiments of common metal ions, which confirmed that the fluorescence recovery by other metal ions is very weak or even unrestored, showing high specificity and sensitivity AlS4Pc-Alcian blue 8GX to Hg(II). Thus, a new fluorimetry for Hg(II) with high specificity and high sensitivity in a wide concentration range has been established using AlS4Pc-Alcian blue 8GX associate as a red-emitting fluorescent probe. It is more noteworthy that this study opens a new way for development and application of functional phthalocyanine based red-emitting fluorescent probes.


Asunto(s)
Azul Alcián/química , Técnicas Biosensibles , Indoles/química , Mercurio/aislamiento & purificación , Fluorescencia , Colorantes Fluorescentes/química , Isoindoles , Espectrometría de Fluorescencia
15.
Chin Med Sci J ; 33(4): 252-259, 2018 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-30646989

RESUMEN

Objective To assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). Methods rNAION was established with Rose Bengal and argon green laser in Sprague-Dawley rats. Fundus photography and fundus fluorescein angiography (FFA) were performed to assess the dynamic changes of optic disc in morphology in 90 days and in blood perfusion in 3 hours after the induction of disease. Histological examinations were performed to evaluate the success of modeling. The dynamic blood flow kinetics of posterior ONH in rNAION were measured by Laser Doppler Flowmetry (LDF) on the day 3, 7, 14, 21, and 40 after the disease induction. One-way ANOVA, Student's t-test and Bonferroni adjustment were used for multiple comparisons of kinetic measurements of blood flow. Results Optic disc edema and subsequent resolution associated with the development of optic disc pallor were observed in rNAION. FFA showed that the optic disc was hypofluorescence in the early phase and hyperfluorescence in the late phase. Histological studies suggested edema and loosened tissues of ONH, loss of retinal ganglion cells (RGCs), optic nerve substance and gliosis. Compared to the naive rats, the blood flow kinetics of posterior ONH in rNAION significant reduced at each time point after modeling (F=175.06, P<0.0001). The reductions were specifically remarkable in 14 days after the disease induction (All P<0.01). Conclusions Continuous blood perfusion reduction was found in rNAION, with significant alteration in 14 days after disease induction. Our results provided important information for understanding the hemodynamic changes in rNAION.


Asunto(s)
Hemodinámica/fisiología , Neuropatía Óptica Isquémica/fisiopatología , Animales , Modelos Animales de Enfermedad , Angiografía con Fluoresceína , Humanos , Masculino , Disco Óptico/patología , Disco Óptico/fisiopatología , Neuropatía Óptica Isquémica/patología , Ratas , Ratas Sprague-Dawley , Células Ganglionares de la Retina/fisiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-27366193

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is one of the most common forms of chronic liver disease. Currently, there are no recognized medical therapies effective for NAFLD. Previous studies have demonstrated the effects of total turmeric extract on rats with NAFLD induced by high-fat diet. In this study, serum metabolomics was employed using UHPLC-Q-TOF-MS to elucidate the underlying mechanisms of HFD-induced NAFLD and the therapeutic effects of TE. Supervised orthogonal partial least-squares-discriminant analysis was used to discover differentiating metabolites, and pathway enrichment analysis suggested that TE had powerful combined effects of regulating lipid metabolism by affecting glycerophospholipid metabolism, glycerolipid metabolism, and steroid hormone biosynthesis signaling pathways. In addition, the significant changes in glycerophospholipid metabolism proteins also indicated that glycerophospholipid metabolism might be involved in the therapeutic effect of TE on NAFLD. Our findings not only supply systematic insight into the mechanisms of NAFLD but also provide a theoretical basis for the prevention or treatment of NAFLD.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 749-54, 2016 Mar.
Artículo en Chino | MEDLINE | ID: mdl-27400518

RESUMEN

Tetrasubstituted trimethyl ammonium iodide aluminum phthalocyanine (TTMAAlPc), a positively charged phthalocyanine compound, is an emerging and potentially useful red-emitting fluorescence probe. The study showed that the fluorescence of TTMAAlPc could be quenched by RNA with high efficiency in weak alkaline media, and the degree of quenching has a linear relationship with RNA in a wide concentration range. The mechanism of quenching behavior of RNA on TTMAAlPc was discussed. It was attributed by the static interaction between RNA and TTMAAlPc, and the assembly of TTMAAlPc induced by RNA. Based on this new discovery, a novel method for quantitative determination of RNA at nanogram level has been established. The factors, including the pH of medium, buffer system, reaction time, reaction temperature, the usage of TTMAAlPc as well as the interferences, which affected the determination, were investigated and discussed. Under optimum conditions, the linear range of the calibration curve was 7.71-1 705.57 ng x mL(-1). The detection limit for RNA was 1.55 ng x mL(-1). This method has been applied to the analysis of practical samples with satisfied results. The constructed method is of high sensitivity and has a wide linear range, it also showed strong ability in the tolerance of foreign substances from anions, cations, surfactants and vitamins, all of which are common interferences encountered in the determination of RNA. Besides, it is the first report that the fluorescence quantum yield of TTMAAlPc has been measured at different pH by reference method in this work. The achieved data indicated that the fluorescence quantum yield of TTMAAlPc is larger than 20% and it keeps constant in a wide range of acidity, implying that TTMAAlPc is a high-quality red-emitting fluorescence probe, it has great potential for practical applications, thus is worthy of further study. This work expands the application of phthalocyanine compound in analytical sciences.


Asunto(s)
Colorantes Fluorescentes , Indoles , Compuestos Organometálicos , ARN/química , Límite de Detección , Espectrometría de Fluorescencia
18.
Toxicol Ind Health ; 32(11): 1882-1890, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26229097

RESUMEN

Formaldehyde (FA), a ubiquitous environmental pollutant, has long been suspected of causing adverse male reproductive effects. However, the molecular and cellular mechanisms underlying this phenomenon remain elusive. The overall aim of this study is to clarify the role of mammalian target of rapamycin (mTOR) in male reproductive injuries induced by FA exposure, by which we can further understand the molecular mechanism of FA male reproductive toxicity. In this study, immunohistochemistry, Western blotting, and reverse transcription polymerase chain reaction analysis were used to detect the expression of mTOR molecule in testicular tissues. We found that FA exposure inhibits the expression of mTOR in a dose-dependent manner. Combined with our earlier finding, we found the decreasing expression of mTOR in testicular tissue were consistent with the changes of testicular structure and autophagy levels. In summary, our data suggested that mTOR molecule might be involved in male reproductive injuries induced by FA exposure.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2203-7, 2015 Aug.
Artículo en Chino | MEDLINE | ID: mdl-26672294

RESUMEN

Determination of chondroitin sulfate in the biomedical field has an important value. The conventional methods for the assay of chondroitin sulfate are still unsatisfactory in sensitivity, selectivity or simplicity. This work aimed at developing a novel method for sensitive and selective determination of chondroitin sulfate by fluorimetry. We found that some kinds of cationic surfactants have the ability to quench the fluorescence of tetrasulfonated aluminum phthalocyanine (AlS4Pc), a strongly fluorescent compound which emits at red region, with high efficiency. But, the fluorescence of the above-mentioned fluorescence quenching system recovered significantly when chondroitin sulfate (CS) exits. Tetradecyl dimethyl benzyl ammonium chloride(TDBAC) which was screened from all of the candidates of cationic surfactants was chosen as the quencher because it shows the most efficient quenching effect. It was found that the fluorescence of AlS4Pc was extremely quenched by TDBAC because of the formation of association complex between AlS4Pc and TDBAC. Fluorescence of the association complex recovered dramatically after the addition of chondroitin sulfate (CS) due to the ability of chondroitin sulfate to shift the association equilibrium of the association, leading to the release of AlS4Pc, thus resulting in an increase in the fluorescence of the reaction system. Based on this phenomenon, a novel method with simplicity, accuracy and sensitivity was developed for quantitative determination of CS. Factors including the reaction time, influencing factors and the effect of coexisting substances were investigated and discussed. Under optimum conditions the linear range of the calibration curve was 0.20~10.0 µg · mL(-1). The detection limit for CS was 0.070 µg · mL(-1). The method has been applied to the analysis of practical samples with satisfied results. This work expands the applications of AlS4Pc in biomedical area.


Asunto(s)
Sulfatos de Condroitina/análisis , Colorantes Fluorescentes , Aniones , Fluorescencia , Fluorometría , Indoles , Isoindoles , Límite de Detección , Compuestos Organometálicos , Espectrometría de Fluorescencia , Tensoactivos
20.
Dongwuxue Yanjiu ; 36(3): 152-60, 2015 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-26018858

RESUMEN

Non-human primates often live in socially stable groups characterized by bonded relationships among individuals. Social organization can be used to evaluate living conditions and expansion potential. Bisexual group size, ratio of males to females and group composition are essential elements determining the type of social organization. Although the first report on Shortridge's capped langurs (Trachypithecus shortridgei) was in the 1970s, until now, the species only inhabits forests of the Dulongjiang valley in northwest Yunnan, China, with c. 250-370 individuals in 19 populations. To understand its social organization, we collected data from five groups of Shortridge's langurs at Silaluo in the Dulongjiang valley during August 2012-October 2013. Family groups consist of one adult male, 2-3 adult females and up to five young. Group size averaged 8 (7-9) individuals. The ratio of adult males to females (M/F) was 1:2.9, infants to adult females was (I/F) 1:2.2; and ratio of adults to immatures was 1:1.2, indicating the potential of a population increasing. Birth season was during March-July and the inter-birth interval was two years.


Asunto(s)
Cercopithecidae/psicología , Conducta Social , Animales , Conducta Animal , Cercopithecidae/fisiología , China , Ecosistema , Femenino , Masculino
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