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1.
J Nat Prod ; 87(4): 1209-1216, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38394380

RESUMEN

Seven new 4-hydroxy-6-phenyl-2H-pyran-2-one (HPPO) derived meroterpenoids, 1-methyl-12a,12b-epoxyarisugacin M (1), 1-methyl-4a,12b-epoxyarisugacin M (2), 2,3-dihydroxy-3,4a-epoxy-12a-dehydroxyisoterreulactone A (3), 2-hydroxy-12a-dehydroxyisoterreulactone A (4), 3'-demethoxyterritrems B' (5), 4a-hydroxyarisugacin P (6), and 1-epi-arisugacin H (7), together with two known analogues (8 and 9), were isolated from the marine-derived fungal strain Penicillium sp. SCSIO 41691. Their structures were elucidated by spectroscopic methods, and the absolute configurations of compounds 1 and 3 were determined by single-crystal X-ray diffraction. Among them, 1 and 2 had a unique methyl migration in the basic meroterpenoid skeleton with a 12a,12b-epoxy or 4a,12b-epoxy group, and 3 was a highly oxygenated HPPO-derived meroterpenoid featuring a rare 6/5/6/6/6/6 hexacyclic system with a 3,4a-epoxy group. Biologically, 5 exhibited inhibitory activity against lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells with an IC50 value of 21 µM, more potent than the positive control indomethacin.


Asunto(s)
Penicillium , Terpenos , Penicillium/química , Terpenos/farmacología , Terpenos/química , Terpenos/aislamiento & purificación , Estructura Molecular , Animales , Ratones , Células RAW 264.7 , Óxido Nítrico/biosíntesis , Cristalografía por Rayos X , Biología Marina , Lipopolisacáridos/farmacología
2.
Ying Yong Sheng Tai Xue Bao ; 34(11): 3105-3113, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37997422

RESUMEN

Pollen (spores and pollen) allergy caused by green areas is one of the most serious environmental epidemics endangering urban public health. The pollen allergy rate in China reached 17.8% in 2022, characterized by a wide age range of onset, severity and diversity of symptoms. The aims of this study were to verify the consistency of the prediction results of pollen concentration and the index of allergenicity of urban green zones (IUGZA) equation, and to clarify the dispersal pattern of tree pollen in the urban alleys of cities with high density of static wind. We selected representative high, medium and low allergenic areas based on the allergenic stress in urban alleys of Qingyang District, Chengdu calculated by IUGZA equation, and monitored the pollen concentrations by selecting points and indicator species within the three allergenic areas. There was a consistency in the variation of pollen concentration in urban alleys of the three areas, with the highest pollen concentration in March. Mean pollen concentration showed a pattern of spring > autumn > summer > winter. The main pollen sources belonged to Ginkgo, Platanus, Firmiana and Cedrus, accounting for 42.4%, 16.3%, 9.0% and 6.5% of the total pollen, respectively. Wind speed had the greatest effect on pollen concentration and its dispersal distance in the urban alley. The horizontal dispersal distance of pollen was up to 260 m, and the number of pollen showed a significant negative linear correlation with the distance away from the pollen sources. The concentration of exotic pollen collected at the high site (4.5 m above ground) was much lower than that at the near-ground site (1.5 m above ground), but without difference in the types of pollen. The results of allergenic risk predicted by the IUGZA equation were consistent with the actual measured pollen concentration, which could be used in high-density static wind city.


Asunto(s)
Alérgenos , Polen , Ciudades , China , Estaciones del Año , Monitoreo del Ambiente
3.
Ying Yong Sheng Tai Xue Bao ; 33(6): 1615-1621, 2022 Jun.
Artículo en Chino | MEDLINE | ID: mdl-35729140

RESUMEN

We examined the pollen allergy risk of street trees in urban alleys, with 410 urban alleys in Qingyang District, Chengdu as an example. On the basis of recording the characteristics of street trees, we calculated the index of allergenicity of urban green zones (IUGZA) values and overlay the regional population density map, and finally obtained the pollen allergy risk map of urban alleys in Qingyang District. The results showed that there were 32461 street trees in 410 urban alleys, belonging to 27 families, 41 genera, and 52 species. The distribution of tree species was extremely uneven, with excessive plantation of Ficus concinna (31.8%), Ginkgo biloba (12.9%) and Cinnamomum camphora (8.5%). The risk of pollen allergy in urban alleys was high, with an average IUGZA value of 2.61 and spring as the primary risk season. Among them, 175 alleys were at the most low allergy degree (IUGZA=0-1), 174 alleys at low degree of allergy (IUGZA=1-5), and 6 alleys at extremely high risk of allergy (IUGZA=15-20). Results of correlation analysis showed that mean tree height and canopy-to-street area ratio were the key factors affecting IUGZA of street trees in urban alleys. After superimposing the population density map, Shaocheng Street, Caoshi Street, Xiyuhe Street, Funan Street, and Supo Street had a high risk of pollen allergy.


Asunto(s)
Hipersensibilidad , Rinitis Alérgica Estacional , Alérgenos/efectos adversos , China/epidemiología , Ciudades , Humanos , Medición de Riesgo , Árboles
4.
Bioorg Chem ; 111: 104871, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33839581

RESUMEN

Nine previously undescribed butyrolactone and sesquiterpene derivatives, named cyclopentanone A (1), subamolides F and G (2 and 3), secosubamolide F (4), rupestonic acids J - L (5-7), linderaguaianols A and B (8 and 9), together with six known ones 10-15 were isolated from the roots of Lindera glauca. Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, quantum chemical calculations, and Mo2(AcO)4-induced circular dichroism. Compound 1 that possessed a unique five-membered cyclopentane skeleton with a side chain was rarely found from natural sources. The biogenetic pathway for 1-4 was postulated. Secosubamolide F (4) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 cells with IC50 value of 1.73 ± 0.18 µM and also significantly suppressed the production of iNOS. The binding interactions between 4 and iNOS were investigated using docking analyses.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Lindera/química , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Óxido Nítrico/antagonistas & inhibidores , Raíces de Plantas/química , Sesquiterpenos/farmacología , Animales , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/metabolismo , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Relación Estructura-Actividad
5.
Chem Commun (Camb) ; 56(10): 1517-1520, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-31919484

RESUMEN

The pseudoguaianelactones A (1) and B (2), two novel sesquiterpene lactones with an unprecedented [5,7,7] ring system featuring an α-methylene-γ-lactone moiety, together with a new pseudoguaianelactone C (3) were isolated from the roots of Lindera glauca. Pseudoguaianelactones A-C (1-3) inhibited nitric oxide (NO) production, with IC50 values ranging from 1.38 to 4.00 µM. Moreover, all compounds significantly suppressed the production of pro-inflammatory mediators (TNF-α, IL-6, IL-1ß and PGE2) and the protein expression of the enzymes iNOS and COX-2.


Asunto(s)
Antiinflamatorios/química , Ciclooxigenasa 2/metabolismo , Lindera/química , Óxido Nítrico Sintasa de Tipo II/metabolismo , Sesquiterpenos/química , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Cristalografía por Rayos X , Citocinas/metabolismo , Lindera/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Conformación Molecular , Óxido Nítrico/metabolismo , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Células RAW 264.7 , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología
6.
Chem Commun (Camb) ; 55(77): 11642, 2019 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-31512684

RESUMEN

Correction for 'Synthesis of hydrophobic and hydrophilic TiO2 nanofluids for transformable surface wettability and photoactive coating' by Jie Hu et al., Chem. Commun., 2019, 55, 9275-9278.

7.
Chem Commun (Camb) ; 55(63): 9275-9278, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31259354

RESUMEN

Two modified TiO2 nanofluids were developed, with either hydrophobic or hydrophilic properties. The hydrophobic TiO2 nanofluid, embedded in an organo-silyl salt, could be transformed into a hydrophilic TiO2 nanofluid by exchange of the chloride with an organo-sulphonate ion. Both modified TiO2 nanofluids exhibited high fluidity, thermal stability and photoactivity.

8.
Zhonghua Nan Ke Xue ; 24(3): 211-215, 2018 Mar.
Artículo en Chino | MEDLINE | ID: mdl-30161305

RESUMEN

OBJECTIVE: To investigate the relationship of the characteristics of sperm donors with the results of screening and provide some reference for the screening of sperm donors. METHODS: We statistically analyzed the screening data about 12 362 sperm donors at the Guangdong Human Sperm Bank from January 2003 to June 2017 and the relationship of the eligibility rate of screening with the donors' age, education, occupation, marriage, and fatherhood. RESULTS: Of the 12 362 sperm donors, 3 968 (32.1%) met the standards of semen quality and 3 127 (25.3%) filled all the requirements of sperm donation. The eligibility rate of screening was 27.7% in the donors aged 20-24 years, 24.3% in those aged 25-29 years, 23.8% in those aged 30-34 years, and 17.5% in those aged =≥35 years (P < 0.01); 23.5% in the senior high school students, 24% in the junior college students, 25.9% in the undergraduates, and 30.3% in the postgraduates (P < 0.01); 29.3% in the students versus 22.9% in the others (P < 0.01), 41.5% in the married versus 20.7% in the unmarried (P < 0.01), and 45.6% in the fathers versus 20.9% in the childless husbands (P < 0.01). CONCLUSIONS: A higher eligibility rate of screening was found among the sperm donors aged <35 years or with a bachelor's or higher degree, particularly among students.


Asunto(s)
Espermatozoides , Donantes de Tejidos , Adulto , Humanos , Masculino , Análisis de Semen/normas , Estudiantes/estadística & datos numéricos , Donantes de Tejidos/estadística & datos numéricos , Obtención de Tejidos y Órganos , Adulto Joven
9.
Ying Yong Sheng Tai Xue Bao ; 29(2): 433-440, 2018 Feb.
Artículo en Chino | MEDLINE | ID: mdl-29692056

RESUMEN

We examined the effects of temperature on SOC mineralization rate (Cmin) and enzyme kinetic parameters in soils of two different latitudinal forests, i.e., broad-leaved Korean pine forest in Changbai Mountain at higher latitude and evergreen broad-leaved forest in Dinghu Mountain at lower latitude. The results showed that the soil Cmin increased with temperature, and the Cmin and Q10(Cmin) of the Changbai Mountain forest soil were higher than those of the Dinghu Mountain forest soil. The maximal rates of velocity (Vmax) and the half-saturation constant (Km) of the Changbai Mountain forest soil were higher relative to the Dinghu Mountain soil for both soil ß-glucosidase (ßG) and N-acetyl-ß-D-glucosaminidase (NAG), but being opposite for catalytic efficiency (Vmax/Km). Both Vmax and Vmax/Km of ßG and NAG increased with the increase of incubation temperature, while Km decreased, i.e., the affinity of enzymes to the substrate were increased. Inconsistent with the soil Q10 (Cmin), Q10(Vmax) and Q10(Km) of the soil ßG were higher in Dinghu Mountain forest soil than those in the Changbai Mountain forest soil. The mechanisms underlying the effects of temperate variation on Cmin and the enzyme kinetic parameters were different, and thus the temperature sensitivity of Cmin and enzyme kinetic parameters should be considered differentially in the models of soil biochemical process.


Asunto(s)
Carbono , Bosques , Suelo/química , China , Pinus , Temperatura
10.
Appl Microbiol Biotechnol ; 79(6): 1019-26, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18542951

RESUMEN

In order to detect monoclonal antibodies (MAbs) from insufficient and unavailable human proteins, yeast cells were engineered to display human antigens on their surface and consequently endowed with the ability to specifically bind antibodies. Thus, a fusion gene for the expression of the human proteasome subunit alpha 6 (hPSA6) and human profilin I (hProI) were assembled, respectively, with a His.tag marker at the C-terminal and displayed on yeast surface. With anti-His.tag MAb as the primary antibody and the fluorescein isothiocyanate-conjugated goat anti-mouse Immunoglobulin G as the second antibody, the surface display of hPSA6 and hProI were verified by immunofluorescence labeling. The antigen-displayed yeast particles were used for MAbs detection from ascites through both immunofluorescence and yeast-enzyme-linked immunosorbent assay (ELISA) methods. The results were verified by Western blotting and indirect ELISA. By improving the sensitivity, the novel MAbs detection can be applied in the generation and screening of positive hybridoma. It is suggested that by combining the DNA immunization, the present study can evolve into a quick and protein-free way of MAbs production for insufficient and unavailable antigen.


Asunto(s)
Anticuerpos/inmunología , Antígenos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Citometría de Flujo/métodos , Ingeniería de Proteínas , Saccharomyces cerevisiae/inmunología , Animales , Antígenos/genética , Antígenos/metabolismo , Western Blotting , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Expresión Génica , Humanos , Hibridomas/inmunología , Ratones , Profilinas/genética , Profilinas/inmunología , Profilinas/metabolismo , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/inmunología , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
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