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1.
J Environ Manage ; 314: 115081, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35460987

RESUMEN

Starting in 2013, China's key polluting firms have been required to install continuous emissions monitoring systems (CEMS) and to publish the data for real-time oversight and public scrutiny. However, the CEMS data has rarely been used in local environmental law enforcement because its quality is still of great concern. A lack of criteria to evaluate data quality is one of the causes. In this paper, we design a comprehensive analytical framework for evaluating the quality of CEMS data, which includes completeness, accuracy, and authenticity. To demonstrate the applicability of the framework, we build a CEMS dataset for key polluting firms in Henan province from 2017 to 2019 by scraping the CEMS data from a public platform. We then conduct a comprehensive evaluation using our proposed framework. Some data quality issues are identified. About one-third of the firms did not meet official guidelines for data completeness. When comparing the CEMS data with onsite measurement results, we observe statistically significant inconsistencies in about one-fifth of the firms. In addition, we find evidence that some firms might manipulate CEMS data by strategically turning down the CEMS when a pollutant's concentration is expected to exceed the limit. Our framework can be expanded by incorporating more evaluation methods and data. We suggest that government agencies should implement a comprehensive framework to enhance the quality of CEMS data, thereby facilitating its application in law enforcement.


Asunto(s)
Exactitud de los Datos , China
2.
Chem Biodivers ; 18(6): e2100139, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33973702

RESUMEN

Shengxuening (SXN) is a Chinese patent medicine with main ingredients (including chlorophyll derivatives and sodium iron chlorophyllin) extracted from silkworm excrement. SXN exhibited efficacy in clinical trials of renal anemia and iron deficiency anemia; however, the specific mechanisms remain unclear. This study found that SXN increased the number of peripheral blood cells and improved the bone marrow morphology in myelosuppressed mouse model, reversed the reduction in body weight and spleen indices, and increased the serum levels of erythropoietin and granulocyte-macrophage colony-stimulating factor. Quantitative real-time PCR array and Western blot analysis showed the enhanced expression of stem cell factor (SCF), JAK2, and STAT3 in the liver. These results suggested that SXN promoted the recovery of hemopoietic function in myelosuppressed models by increasing the secretion of hematopoietic factors and activating the JAK2/STAT3 pathway. Therefore, this medicine may be applied as therapeutic pharmaceutical drug to mitigate myelosuppression.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Janus Quinasa 2/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Bombyx , Células Cultivadas , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Humanos , Janus Quinasa 2/genética , Células K562 , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Estructura Molecular , Factor de Transcripción STAT3/genética , Transducción de Señal/efectos de los fármacos
3.
Zhongguo Zhong Yao Za Zhi ; 46(15): 3877-3885, 2021 Aug.
Artículo en Zh | MEDLINE | ID: mdl-34472263

RESUMEN

Twenty-six compounds, including sixteen meroterpenoids(1-16), a triterpenoid(17), four terpenoid derivatives(18-21), and five aromatic compounds(22-26), were isolated from the leaves of Psidium guajava. Their structures were identified by spectroscopic analyses including NMR and MS. Compounds 21-26 were obtained from plants of Psidium for the first time. Based on the structure,(R)-2-ethylhexyl 2H-1,2,3-triazole-4-carboxylate(24 a), an α-glucosidase inhibitor recently isolated from Paramignya trimera, should be revised as compound 24. Meroterpenoids 1-16 were evaluated for their antitumor and antifungal activities. Meroterpenoids psiguajadial D(4), guapsidial A(5), 4,5-diepipsidial A(7), guadial A(14), and guadial B(15) showed cytotoxicities against five human tumor cell lines(HL-60, A-549, SMMC-7721, MCF-7, and SW-480), among which 5 was the most effective with an IC_(50) of 3.21-9.94 µmol·L~(-1).


Asunto(s)
Psidium , Antifúngicos/farmacología , Humanos , Espectroscopía de Resonancia Magnética , Extractos Vegetales , Hojas de la Planta , Terpenos
4.
J Nat Prod ; 82(2): 221-231, 2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30702286

RESUMEN

Ten new prenylated indole diterpene alkaloids, tolypocladin A-J (1-10), including four chlorinated metabolites, have been isolated from a culture of a mine-soil-derived fungus, Tolypocladium sp. XL115. The structures and absolute configurations of 1-10 were determined by spectroscopic analysis, ECD calculations, and comparison with known compounds. Compounds 1 and 8 displayed significant antimicrobial activities. In addition, compound 1 also showed weak cytotoxic activity against all tested human cancer cell lines and suppressed the growth and viability of the patient-derived HCC cells T1224.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Alcaloides Diterpénicos/aislamiento & purificación , Hypocreales/metabolismo , Indoles/aislamiento & purificación , Microbiología del Suelo , Línea Celular Tumoral , Alcaloides Diterpénicos/química , Alcaloides Diterpénicos/farmacología , Humanos , Espectroscopía de Resonancia Magnética
5.
Chem Biodivers ; 16(6): e1900116, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30957928

RESUMEN

Two new prenylated indole diterpenoids, tolypocladins K and L (1 and 2), together with a known analog terpendole L (3), were isolated from the solid fermentation culture of a mine soil-derived fungus Tolypocladium sp. XL115. Their structures and relative configurations were determined by comprehensive spectroscopic data analysis, as well as by comparison of their NMR data with those related known compounds. Compound 3 exhibited remarkable antibacterial activity against Micrococcus luteus with an MIC value of 6.25 µg/mL, and compounds 1 and 3 displayed moderate antifungal activity selectively against tested strains with MIC values of 25-50 µg/mL.


Asunto(s)
Antiinfecciosos/química , Diterpenos/química , Hongos/química , Antiinfecciosos/farmacología , Diterpenos/farmacología , Hongos/efectos de los fármacos , Hongos/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Indoles/química , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Microbiología del Suelo
6.
J Asian Nat Prod Res ; 21(9): 851-858, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30129376

RESUMEN

Three new 3,4,6-trisubstituted α-pyrone derivatives, namely 6-(2'R-hydroxy-3'E,5'E-diene-1'-heptyl)-4-hydroxy-3-methyl-2H-pyran-2-one (1), 6-(2'S-hydroxy-5'E-ene-1'-heptyl)-4-hydroxy-3-methyl-2H-pyran-2-one (2), and 6-(2'S-hydroxy-1'-heptyl)-4 -hydroxy-3-methyl-2H-pyran-2-one (3), together with one known compound trichodermic acid (4), were isolated from the solid-substrate fermentation culture of Penicillium ochrochloronthe associated the roots of Taxus media. Compounds 1-4 displayed the antimicrobial activity selectively against tested fungal and bacterial strains with minimum inhibitory concentration (MIC) values ranging from 12.5 to 100 µg/ml. Furthermore, we found that only compound 4 exhibited moderate cytotoxicity against five human cancer cells (A549, LN229, MGC, LOVO, and MDA231) with IC50 values of 51.45, 23.43, 39.16, 46.97, and 42.85 µg/ml, respectively.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Antineoplásicos/farmacología , Penicillium/química , Pironas/química , Antibacterianos/química , Antifúngicos/química , Antineoplásicos/química , Bacterias/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular , Hongos/efectos de los fármacos , Humanos , Estructura Molecular
7.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37796096

RESUMEN

Moisture ingress is one of the major causes of aging in oil-paper insulated transformers; the measurement of the moisture content of the insulating material is thus necessary during transformer disassembly for maintenance. One critical engineering consideration is the need for rapid and nondestructive moisture content measurement of the oil-paper insulation to minimize the power-outage time. Herein, a rapid characterization method for the moisture content of oil-paper insulation based on the dielectric response obtained using a microstrip petal-like ring resonator (MPRR) is proposed. The geometric parameters of the resonator and dielectric response model were established based on simulations and theoretical analysis. The geometry of the resonant ring was optimized by modifying the originally circular ring structure of the microstrip ring resonator (MRR) into a petal-like ring structure; this increases the number of resonant peaks from five to seven in the frequency range of 0.5-6.0 GHz for the same electrode area. The effects of the coupling mode, coupling gap, and microstrip ring size on the resonance characteristics of the MPRR were simulated and analyzed. Compared with the MRR, the MPRR has the advantages of a reduced fundamental resonant frequency and a smaller resonant-ring area that improves radiation efficiency. The impact of moisture content on the dielectric response of the pressboard obtained using the MPRR was studied. A moisture-calculation equation based on the measured dielectric response for a selected type of pressboard was established by the Lasso regression. The results of verification experiments show that the error of the proposed method is sufficient for practical applications.

8.
Nat Commun ; 14(1): 1678, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36966127

RESUMEN

Pure organic phosphors capable of room-temperature phosphorescence show a great potential in organic light-emitting diodes, while it is limited by the big challenge to realize efficient electroluminescence under electric excitation. Herein, we develop a class of organic phosphors based on acridine as the electron donor, triazine as the electron acceptor and oxygen as the bridge between them. Benefitting from the characteristic donor-oxygen-acceptor geometry, these compounds are found to behave an exciting aggregation-induced organic room-temperature electrophosphorescence, and achieve a record-high external quantum efficiency of 15.8% for non-doped devices. Furthermore, they can sensitize multi-resonant emitters in the absence of any additional wide bandgap host, leading to an effective narrowband emission with a peak external quantum efficiency of 26.4% and a small full-width at half maximum of 26 nm. The results clearly indicate that donor-oxygen-acceptor geometry is a promising strategy to design organic phosphors suitable for organic light-emitting diodes.

9.
Fitoterapia ; 152: 104914, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33940066

RESUMEN

Two novel sulfur-containing dibenzofurans, sorbusins A (1) and B (2), two unprecedented biphenyl glycosides, 2'-hydroxyaucuparin 2'-O-ɑ-L-rhamnoside (3) and noraucuparin 5-O-ɑ-L-rhamnoside (4), and four known analogues (5-8), were isolated from Sorbus pohuashanensis suspension cell induced by yeast extract. Their structures were elucidated based on spectroscopic analyses and quantum calculation of 13C NMR data. Structurally, compound 1 possessed a rare naturally occurring benzothiazole moiety and represents the first example of thiazole fused dibenzofuran. A plausible biosynthetic pathway for the sulfur-containing dibenzofurans is proposed. These dibenzofuran and biphenyl phytoalexins were evaluated for their antimicrobial activities against pathogenic fungi and drug-resistant bacteria. Compound 7 exhibited significant antibacterial activity against methicinllin-resistant Staphylococcus aureus with an MIC value of 3.13 µg/mL.


Asunto(s)
Antiinfecciosos/farmacología , Dibenzofuranos/farmacología , Glicósidos/farmacología , Sesquiterpenos/farmacología , Sorbus/química , Antiinfecciosos/aislamiento & purificación , Dibenzofuranos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Sesquiterpenos/aislamiento & purificación , Fitoalexinas
10.
Artículo en Inglés | MEDLINE | ID: mdl-30941201

RESUMEN

Shengxuening (SXN) tablet is extracted from the excrement of the silkworm and has effects on hematopoiesis. The main components of SXN are chlorophyll derivatives and sodium iron chlorophyllin (SIC). The present study aims to investigate the efficiency and safety of SXN on iron deficiency anemia. This phase IV, multicenter, open-label, randomized clinical trial was conducted in 31 hospitals in China from June 2001 to April 2002. Adults and children were randomly divided into low-dose (L-SXN), medium-dose (M-SXN), and high-dose (H-SXN) groups, respectively. The course of treatment was 1 month. Peripheral hemogram levels and iron status were examined before and after treatment. Adults in all three dose groups demonstrated a significant increase in hemoglobin (HGB) concentration. Children who received SXN treatment in medium and high doses also demonstrated increased HGB concentration. Reticulocyte counts increased at the end of treatment in the M-SXN and H-SXN adult groups and in the M-SXN child group. For both children and adults, SXN in the three dose groups was found to significantly elevate red blood cell level, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. The total effective rate in the SXN-treated group reached 84.8%. The incidence of adverse events was 4.07%. The most common side effects were nausea (2.83%), diarrhea (0.74%), and rash (0.25%). SXN was proved to be efficient and safe for adults and children with iron deficiency anemia.

11.
Org Lett ; 21(4): 1078-1081, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30730149

RESUMEN

A pair of enantiomeric norsesquiterpenoids, (+)- and (-)-preuisolactone A (1) [(+)-1 and (-)-1)] featuring an unprecedented tricyclo[4.4.01,6.02,8]decane carbon scaffold were isolated from Preussia isomera. Their structures were determined by spectroscopic and computed methods and X-ray crystallography. Compounds (+)-1 and (-)-1 are two rare naturally occurring sesquiterpenoidal enantiomers. A plausible biosynthetic pathway for 1 is proposed. Additionally, (±)-1 exhibited remarkable antibacterial activity against Micrococcus luteus with an MIC value of 10.2 µM.


Asunto(s)
Antibacterianos/farmacología , Ascomicetos/química , Compuestos Heterocíclicos/farmacología , Micrococcus luteus/efectos de los fármacos , Sesquiterpenos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Estereoisomerismo
12.
Fitoterapia ; 133: 146-149, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30654129

RESUMEN

Three new hopane-type triterpenoids (1-3), fern-7(8)-en-19α, 28-diol (1), pteron-14-ene-7α,19α,28-triol (2) and 3ß,4α,25-trihydroxyfilican (3), were isolated from the aerial parts of Adiantum capillus-veneris. Their structures were determined by NMR spectroscopic and mass spectrometric data. Compounds 2 and 3 exhibited remarkable antifungal activity against Helminthosporium maydis and Alternaria alternata with MIC values of 12.5-3.125 µg/mL, and compound 3 also against Verticillium dahliae Kleb with an MIC value of 3.125 µg/mL. In addition, compounds 1-3 also displayed weak antibacterial activity against Micrococcus lysodeikticus, Bacterium paratyphosum B and Pseudomonas aeruginosa with an MIC value of 100 µg/mL.


Asunto(s)
Adiantum/química , Antibacterianos/farmacología , Antifúngicos/farmacología , Triterpenos/farmacología , Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Componentes Aéreos de las Plantas/química , Triterpenos/aislamiento & purificación
13.
Fitoterapia ; 130: 247-250, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30240844

RESUMEN

Three new phenanthrenes (1-3), designated as 2-methoxy-1,6-dimethyl-5-vinyl-9, 10-dihydrophenanthren-7-ol, 1,6-dimethyl-4,5-dihydropyrene-2,7-diol and 1-(3,7- dihydroxy-2,8-dimethyl-9,10-dihydrophenanthren-1-yl)ethanone, were isolated from the aerial parts of Juncus effusus. Their structures were determined by extensive spectroscopic experiments (NMR and MS) and comparing with those related known compounds. The antifungal and antibacterial activities of 1-3 were evaluated. Compound 1 showed remarkable antifungal activities against six agricultural pathogenic fungi (Rhizoctonia solani, Verticillium dahliae Kleb, Sclerotinia sclerotiorum, Gibberella saubinetii, Bipolaris zeicola, and Phytophthora parasitica) with minimum inhibitory concentration (MIC) values ranging from 3.125 to 12.5 µg/mL, and also displayed significant antibacterial activities against two human pathogenic bacteria (Bacterium paratyphosum B and Micrococcus lysodeikticus) with MIC values of 12.5 and 25 µg/mL, respectively.


Asunto(s)
Antibacterianos/farmacología , Fungicidas Industriales/farmacología , Magnoliopsida/química , Fenantrenos/farmacología , Antibacterianos/aislamiento & purificación , China , Fungicidas Industriales/aislamiento & purificación , Estructura Molecular , Fenantrenos/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Componentes Aéreos de las Plantas/química , Plantas Medicinales/química
14.
Nat Prod Res ; 32(22): 2625-2631, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28927292

RESUMEN

Two new alkylated furan derivatives, 5-(undeca-3',5',7'-trien-1'-yl)furan-2-ol (1) and 5-(undeca-3',5',7'-trien-1'-yl)furan-2-carbonate (2), were isolated from the crude extract of the plant endophytic fungus Emericella sp. XL029 associated with the leaves of Panax notoginseng. The anti-agricultural pathogenic fungal assay indicated that compound 1 displayed significant activity against all tested fungi with minimum inhibitory concentrations (MIC) values from 25 to 3.1 µg/mL, while compound 2 displayed activity against all tested fungi except for Rhizoctonia solani and Fusarium oxysporum with MIC values from 50 to 12.5 µg/mL. Furthermore, compounds 1-2 also exhibited significant inhibitory activity against eight of thirteen tested bacteria with MIC values ranging from 50 to 6.3 µg/mL.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Emericella/química , Furanos/farmacología , Panax notoginseng/microbiología , Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Bacterias/efectos de los fármacos , Furanos/aislamiento & purificación , Fusarium/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Hojas de la Planta/microbiología , Rhizoctonia/efectos de los fármacos
15.
Fitoterapia ; 122: 45-51, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28842357

RESUMEN

Six new alkenylated tetrahydropyran derivatives belonged to polyketides, designated as (12R,13R)-dihydroxylanomycinol (1), (12S,13S)-dihydroxylanomycinol (2), (12R,13S)-dihydroxylanomycinol (3) and (12S,13R)-dihydroxylanomycinol (4), (12S,13R)-N-acetyl-dihydroxylanomycin (5) and (12S,13S)-N-acetyl-dihydroxylanomycin (6), together with one related known compound lanomycinol (7) were isolated from the liquid cultures of Westerdykella dispersa obtained from the marine sediments. Their structures and absolute configurations were determined on the basis of extensive analysis of NMR spectra combined with comparison of NMR data to those of known compound, and computational method via calculation of the electronic circular dichroism (ECD). The anti-agricultural pathogenic fungal and antibacterial activities of all isolated compounds were evaluated. Compounds 1-7 exhibited moderate antifungal activities selectively against tested fungal strains with minimum inhibitory concentration (MIC) values ranging from 12.5 to 50µg/mL, and weak antibacterial activities selectively against tested antibacterial strains with MIC value at 100µg/mL.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Ascomicetos/química , Sedimentos Geológicos/microbiología , Piranos/farmacología , Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Piranos/aislamiento & purificación
16.
Sci Rep ; 7(1): 11956, 2017 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-28931947

RESUMEN

Six new cytochalasans, designated as 18-oxo-19,20-dihydrophomacin C (1), 18-oxo-19-methoxy-19,20- dihydrophomacin C (2), 18-oxo-19-hydroxyl-19,20-dihydrophomacin C (3), 19,20-dihydrophomacin C (4), 19-methoxy-19,20-dihydrophomacin C (5), 19-hydroxyl-19,20-dihydrophomacin C (6), and one new tyrosine-derived alkaloid named as gymnastatin Z (8), together with two known compounds, phomacin B (7) and triticone D (9), were isolated from a solid-substrate fermentation culture of Westerdykella dispersa which was derived from marine sediments. Their structures were established on the basis of spectroscopic analysis using 1D and 2D NMR techniques, and comparison of NMR data to those of known compounds. The anti-bacterial and cytotoxic activities assays of all isolated compounds were evaluated against eight human pathogenic bacteria and five human cancer cell lines, respectively. Compound 8 exhibited moderate activity against B. subtilis with MIC values of 12.5 µg/mL, while compounds 5, 7 and 8 displayed moderate inhibitory activities against five human cancer cell lines (MCF-7, HepG2, A549, HT-29 and SGC-7901), with IC50 values ranging from 25.6 to 83.7 µM.


Asunto(s)
Alcaloides/aislamiento & purificación , Antibacterianos/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Ascomicetos/metabolismo , Alcaloides/química , Alcaloides/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Ascomicetos/crecimiento & desarrollo , Ascomicetos/aislamiento & purificación , Bacterias/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fermentación , Sedimentos Geológicos/microbiología , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Estructura Molecular
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