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1.
Planta Med ; 87(5): 375-382, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33176377

RESUMEN

In this paper, an HPLC peak fractionation approach combined with homogeneous time-resolved fluorescence analysis is proposed for screening epidermal growth factor receptor inhibitors from Rhei Radix et Rhizoma. With this approach, the amount of sample used for a single HPLC run is sufficient for performing a multiple assay due to the miniaturization ability of the homogeneous time-resolved fluorescence technology. This allows for improving the stability and repeatability of the activity assay for each fraction. From a total of 26 fractions collected from the Rhei Radix et Rhizoma extract, 13 fractions exhibit inhibitory activity against the epidermal growth factor receptor. The structures of activity compounds were determined by HPLC-LTQ-Orbitrap MS, revealing the presence of gallic acid, rhein, and emodin with IC50 values of 21.5, 5.29, and 10.2 µM, respectively. The ligand epidermal growth factor receptor interactions were explored by molecular docking simulations, and the inhibitory effects of the three compounds on A549 cell growth were tested in vitro by an MTT assay. This study demonstrates the suitability of the present screening method for drug discovery in natural products.


Asunto(s)
Medicamentos Herbarios Chinos , Rheum , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/farmacología , Receptores ErbB , Simulación del Acoplamiento Molecular , Rizoma
2.
J Environ Sci (China) ; 101: 1-15, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33334506

RESUMEN

A series of MnM/palygorskite (PG) (M = La, W, Mo, Sb, Mg) catalysts was prepared by the wetness co-impregnation method for low-temperature selective catalytic reduction (SCR) of NO with NH3. Conversion efficiency followed the order Sb > Mo > La > W > Mg. A combination of various physico-chemical techniques was used to investigate the influence of Sb-modified Mn/PG catalysts. MnSb0.156/PG catalyst showed highest NO conversion at low temperatures in the presence of SO2 which reveals that addition of Sb oxides effectively enhances the SCR activity of catalysts. A SO2 step-wise study showed that MnSb0.156/PG catalyst displays higher durable resistance to SO2 than Mn/PG catalyst, where the sulfating of active phase is greatly inhibited after Sb doping. Scanning electron microscopy and X-ray diffraction results showed that Sb loading enhances the dispersion of Mn oxides on the carrier surface. According to the results of characterization analyses, it is suggested that the main reason for the deactivation of Mn/PG is the formation of manganese sulfates which cause the permanent deactivation of Mn-based catalysts. For Sb-doped Mn/PG catalyst, SOx ad-species formed were mainly combined with SbOx rather than MnOx. This preferential interaction between SbOx and SO2 effectively shields the MnOx as active species from being sulfated by SO2 resulting in the improvement of SO2 tolerance on Sb-added catalyst. Multiple information support that, owing to the addition of Sb, original formed MnOx crystallite has been completely transformed into highly dispersed amorphous phase accounting for higher SCR activity.


Asunto(s)
Amoníaco , Catálisis , Compuestos de Magnesio , Oxidación-Reducción , Compuestos de Silicona , Temperatura
3.
Planta ; 242(4): 963-84, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26021606

RESUMEN

MAIN CONCLUSION: We constructed small RNA and degradome sequencing libraries to identify miRNAs and targets involved in tomato pedicel abscission, and confirmed their roles via quantitative real-time PCR. MicroRNAs (miRNAs) are endogenous small RNAs which play crucial negatively regulatory roles at both the transcriptional and post-transcriptional levels in plants; however, limited knowledge is available on the expression profiles of miRNAs and their target genes during tomato pedicel abscission. Taking advantage of small RNA (sRNA) and degradome sequencing technology, a total of 56 known and 11 novel candidate miRNAs targeting 223 mRNA genes were confirmed during pedicel abscission. Gene ontology annotation and KEGG pathway analysis showed that these target genes were significantly enriched in intracellular, membrane-bounded organelle-related biological processes as well as in metabolic, plant-pathogen interaction and hormone signaling pathways. We screened 17 miRNA/target pairs for further analysis and performed quantitative real-time PCR to identify the roles. Cluster analysis of selected miRNAs revealed that the expression profiles of miRNAs varied in different stages of abscission and could be impacted by ethylene treatment. In the present study, the correlations between miRNAs and targets suggested a complex regulatory network of miRNA-mediated target interaction during pedicel abscission. Additionally, the expression profiles of miRNAs and their targets changed by ethylene might be a considerable reason why ethylene promotes pedicel abscission. Our study provides new insights into the expression and regulatory profiles of miRNAs during tomato pedicel abscission.


Asunto(s)
MicroARNs/genética , ARN de Planta/genética , Solanum lycopersicum/genética , Análisis de Secuencia de ARN
4.
Mar Drugs ; 13(3): 1466-80, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25789603

RESUMEN

A new protein, coded as D2-3, was obtained from the marine organism Tegillarca granosa L. by anion exchange and hydrophobic chromatography. The purity of D2-3 was over 99.0% as measured by RP-HPLC. Its molecular weight was shown to be 20.320 kDa by ESI-MS/MS, and the isoelectric point of D2-3 was 4.70. The antitumor activity of D2-3 against four human tumor cell lines was measured by MTT assay. The conformational structure of D2-3 was further characterized by UV-vis, FT-IR and CD spectroscopy. Partial amino acid sequences of D2-3 were determined to be LMMTDVEESR, SSHMLSECRRK, KNGRNVDISHKDKG, SSDPTLMDPDDTNKDR, SSDKNTCSKTEYYTR and SSETMPYDVLDTNEMR via MALDI-TOF-MS and de novo sequencing.


Asunto(s)
Antineoplásicos/farmacología , Arcidae/química , Neoplasias/tratamiento farmacológico , Proteínas/farmacología , Secuencia de Aminoácidos , Animales , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión/métodos , Humanos , Punto Isoeléctrico , Peso Molecular , Neoplasias/patología , Proteínas/química , Proteínas/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría de Masas en Tándem/métodos
5.
World J Microbiol Biotechnol ; 30(1): 175-80, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23864440

RESUMEN

Elicitation is an important strategy to improve production of secondary metabolites in vitro. Artemisinic acid was studied as a novel elicitor to enhance the yield of terpenoid indole alkaloids in the present paper. Our results demonstrated that the concentrations of vindoline and vinblastine were increased by sixfold and twofold, respectively, compared to those of the control group after treatment with artemisinic acid. To elucidate the underlying mechanism, we investigated the gene expression of four enzymes involved in the biosynthetic pathway of vinblastine in the suspension-cultured cells of Catharanthu sroseus. RT-PCR experiment showed that artemisinic acid was able to up-regulate the transcriptions of tryptophan decarboxylase, geraniol 10-hydroxylase, tabersonine 16-hydroxylase and deacetoxyvindoline 4-hydroxylase.


Asunto(s)
Artemisininas/metabolismo , Catharanthus/efectos de los fármacos , Catharanthus/metabolismo , Vinblastina/análogos & derivados , Vinblastina/metabolismo , Vías Biosintéticas/genética , Células Cultivadas , Perfilación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos
6.
Sci Rep ; 14(1): 6094, 2024 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480857

RESUMEN

Potassium testing is an essential test in emergency medicine. Turnaround time (TAT) is the time between specimen receipt by the laboratory and the release of the test report. A brief in-laboratory TAT increases emergency department effectiveness. Optimizing processes to shorten TAT using other tools requires extensive time, resources, training, and support. Therefore, we aimed to find a convenient way to shorten TAT, identify risk factors affecting the timeliness of emergency potassium test reporting, and verify the intervention's effects. The dependent variable was emergency potassium reporting time > 30 or < 30 min. Logistic analysis was performed on monitorable factors, such as sex, age, potassium results, number of items, specimen processing time (including centrifugation and time before specimen loading), critical value ratio, instrument status, shift where the report was issued, specimen status, and work experience, as independent variables. In the multivariate analysis, work experience, instrument failure rate, and specimen processing time were risk factors for emergency blood potassium reporting exceeding 30 min. Improvement measures were implemented, significantly decreasing the timeout rate for acute potassium reporting. Our study confirms the usefulness of logistics in reducing the time required to report potassium levels in the emergency department, providing a new perspective on quality management.


Asunto(s)
Laboratorios de Hospital , Factores de Tiempo , Servicio de Urgencia en Hospital , Manejo de Especímenes , Potasio
7.
Mar Drugs ; 11(12): 4773-87, 2013 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-24317469

RESUMEN

A new in vitro anti-tumor polypeptide, coded as J2-C3, was isolated from Arca inflata Reeve and purified by diethyl-aminoethanol (DEAE)-sepharose Fast Flow anion exchange and phenyl sepharose CL-4B hydrophobic chromatography. J2-C3 was identified to be a homogeneous compound by native polyacrylamide gel electrophoresis (Native-PAGE). The purity of J2-C3 was over 99% in reversed phase-high performance liquid chromatography (RP-HPLC). The molecular weight was determined as 20,538.0 Da by electrospray-ionization mass spectrometry (ESI-MS/MS). J2-C3 was rich in Glx (Gln + Glu), Lys, and Asx (Asp + Asn) according to amino acid analysis. Four partial amino acid sequences of this peptide were determined as L/ISMEDVEESR, KNGMHSI/LDVNHDGR, AMKI/LI/LNPKKGI/LVPR and AMGAHKPPKGNEL/IGHR via MALDI-TOF/TOF-MS and de novo sequencing. Secondary structural analysis by CD spectroscopy revealed that J2-C3 had the α-helix (45.2%), ß-sheet (2.9%), ß-turn (26.0%) and random coil (25.9%). The anti-tumor effect of J2-C3 against human tumor cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the IC50 values of J2-C3 were 65.57, 93.33 and 122.95 µg/mL against A549, HT-29 and HepG2 cell lines, respectively. Therefore, J2-C3 might be developed as a potential anti-tumor agent.


Asunto(s)
Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Péptidos/aislamiento & purificación , Péptidos/farmacología , Secuencia de Aminoácidos , Aminoácidos/química , Antineoplásicos/química , Línea Celular Tumoral , Células HT29 , Células Hep G2 , Humanos , Peso Molecular , Péptidos/química
8.
Lab Med ; 54(6): 574-581, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36864558

RESUMEN

OBJECTIVE: Failure mode and effects analysis (FMEA) was used to identify factors that contribute to quality management deficiencies in laboratory testing of emergency complete blood count (CBC). METHODS: Improvements included instrument updates, personnel training, and laboratory information system optimization. We used operational data from January 2021 (control group) and January 2022 (FMEA group) to compare the risk priority number (RPN) of FMEA, emergency CBC laboratory turnaround time (TAT), error report rate, and specimen failure rate. RESULTS: After the implementation of FMEA, the average RPN dropped from 36.24 ± 9.68 to 9.45 ± 2.25, (t = 20.89, P < .05). Additionally, the median TAT for emergency CBCs decreased from 23 min to 11 min as did the interquartile distance (17-34 min to 8-16 min) (P < .05). The rate of emergency CBC error reports decreased from 1.39% to 0.71% (P < .05), and the specimen failure rate decreased from 0.95% to 0.32% (P < .05). Patient satisfaction also increased from 43% to 74% (P < .05), and the technician-performed morphology assessment pass rate increased from 16.7% to 100% (P < .05). CONCLUSION: Improving the emergency CBC testing process with FMEA can shorten emergency CBC laboratory TAT and reduce specimen failure rates and reporting error rates. The FMEA can be used to improve quality management in emergency CBC laboratories.


Asunto(s)
Laboratorios , Humanos , Recuento de Células Sanguíneas
9.
Photodiagnosis Photodyn Ther ; 43: 103658, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37339692

RESUMEN

Photodynamic therapy (PDT) is a non-invasive treatment method for treating tumors. Under laser irradiation, photosensitizers in tumor tissues generate biotoxic reactive oxygen, which can kill tumor cells. The traditional live/dead staining method of evaluating the cell mortality caused by PDT mainly depends on manual counting, which is time-consuming and relies on dye quality. In this paper, we have constructed a dataset of cells after PDT treatment and trained the cell detection model YOLOv3 to count both the dead and live cells. YOLO is a real time AI object detection algorithm. The achieved results demonstrate that the proposed method has a good performance in cell detection, with a mean average precision (mAP) of 94% for live cells and 71.3% for dead cells. This approach can efficiently evaluate the effectiveness of PDT treatment, thus speeding up treatment development effectively.


Asunto(s)
Aprendizaje Profundo , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes/uso terapéutico , Fotoquimioterapia/métodos , Neoplasias/tratamiento farmacológico , Oxígeno , Línea Celular Tumoral
10.
Nat Prod Res ; 36(5): 1170-1181, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33342306

RESUMEN

A new phenanthrene compound, 7-(4-hydroxybenzyl)-8-methoxy-9,10- dihydrophenanthrene-2,5-diol (HMD), along with five known compounds (Coelonin, DD, Shancidin, HDP and MDD) were isolated from the roots of Cymbidium faberi Rolfe. (CFR). Their structures were identified using various spectroscopic methods. These compounds were reported for the first time in the genus. All isolated compounds were tested by radical-scavenging ability against 1,1-diphenyl-2-picryl-hydrazyl (DPPH), cytotoxic activity against three human cancer cell lines and inflammatory activity. Among them, Shancidin exhibited the stronger DPPH-scavenging activity (IC50=6.67 ± 0.84 µΜ) and cytotoxic activity against three tumour cell lines. Except for HDP, all compounds dose-dependently suppressed production of NO, TNF-α, IL-6 in LPS induced mouse primary peritoneal macrophage and showed anti-inflammatory activity. Moreover, 18 compounds were identified by UHPLC-LTQ-Orbitrap-MS combined with MS database, which provides a basis for further research.[Formula: see text].


Asunto(s)
Orchidaceae , Fenantrenos , Animales , Línea Celular Tumoral , Ratones , Estructura Molecular , Orchidaceae/química , Fenantrenos/química , Fenantrenos/farmacología , Extractos Vegetales , Raíces de Plantas
11.
PLoS One ; 12(1): e0170297, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28107495

RESUMEN

Seed germination is the key step for successful establishment, growth and further expansion of population especially for alien plants with annual life cycle. Traits like better adaptability and germination response were thought to be associated with plant invasion. However, there are not enough empirical studies correlating adaptation to environmental factors with germination response of alien invasive plants. In this study, we conducted congeneric comparisons of germination response to different environmental factors such as light, pH, NaCl, osmotic and soil burials among four alien amaranths that differ in invasiveness and have sympatric distribution in Jiangsu Province, China. The data were used to create three-parameter sigmoid and exponential decay models, which were fitted to cumulative germination and emergence curves. The results showed higher maximum Germination (Gmax), shorter time for 50% germination (G50) and the rapid slope (Grate) for Amaranthus blitum (low-invasive) and A. retroflexus (high-invasive) compare to intermediately invasive A. spinosus and A. viridis in all experimental regimes. It indicated that germination potential does not necessarily constitute a trait that can efficiently distinguish highly invasive and low invasive congeners in four Amaranthus species. However, it was showed that the germination performances of four amaranth species were more or less correlated with their worldwide distribution area. Therefore, the germination performance can be used as a reference indicator, but not an absolute trait for invasiveness. Our results also confirmed that superior germination performance in wide environmental conditions supplementing high seed productivity in highly invasive A. retroflexus might be one of the reasons for its prolific growth and wide distribution. These findings lay the foundation to develop more efficient weed management practice like deep burial of seeds by turning over soil and use of tillage agriculture to control these invasive weed species.


Asunto(s)
Amaranthus/fisiología , Germinación , Amaranthus/clasificación , Amaranthus/crecimiento & desarrollo , China , Concentración de Iones de Hidrógeno , Luz , Ósmosis , Cloruro de Sodio/administración & dosificación , Especificidad de la Especie
12.
J Hazard Mater ; 171(1-3): 634-9, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19581049

RESUMEN

Adsorbent/ferrite composites can adsorb and degrade organics in the organic wastewater treatment. In this study, a rice hull/MnFe(2)O(4) composite (RHM) was prepared via calcination under nitrogen atmosphere and was used to treat organic wastewater with the assistance of microwave radiation. Rice hull was pyrolysed to a porous substrate that consisted of silica and activated carbon under high temperature. Monodisperse spinel MnFe(2)O(4) nanoparticles whose mean diameter is around 59 nm are distributed on the substrate. With the assistance of microwave radiation, RHM was motivated to a hotspot of adsorption and catalysis which could remove more than 70% COD of wastewater within 6 min. The maximum COD removal was 73.5% when the concentration of RHM was 15 mg mL(-1) and the irradiation time of microwave radiation was 6 min. Although the BET surface area and iodine value of RHM are half of rice hull ash (RHA), the COD removal of RHM is 7-20% higher than that of RHA. It is attributed to the presence of MnFe(2)O(4), which enhances the catalytic activity of RHM. RHM can be regenerated via water washing. However, the surface area and the maximum COD removal of RHM decrease for each regeneration cycle. With the advantages of low cost and rapid processing, this novel rice hull/MnFe(2)O(4) composite could gain promising application in wastewater treating-agent.


Asunto(s)
Hierro/química , Manganeso/química , Oryza/metabolismo , Óxidos/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Carbono/química , Catálisis , Química Orgánica/métodos , Yodo/química , Microondas , Oxígeno/química , Dióxido de Silicio/química , Factores de Tiempo , Eliminación de Residuos Líquidos/métodos
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