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1.
RSC Adv ; 13(25): 16935-16942, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37288376

RESUMEN

Perovskite film-quality is a crucial factor to improve the photovoltaic properties of perovskite solar cells, which is closely related to the morphology of crystallization grain size of the perovskite layer. However, defects and trap sites are inevitably generated on the surface and at the grain boundaries of the perovskite layer. Here, we report a convenient method for preparing dense and uniform perovskite films, employing g-C3N4 quantum dots doped into the perovskite layer by regulating proper proportions. This process produces perovskite films with dense microstructures and flat surfaces. As a result, the higher fill factor (0.78) and a power conversion efficiency of 20.02% are obtained by the defect passivation of g-C3N4QDs.

2.
Dalton Trans ; 52(2): 434-443, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36524392

RESUMEN

In this article, a novel triphenylamine-modified salicylaldehyde Schiff base 2-(((4-(diphenylamino)phenyl)imino)methyl)-4-(pyridine-4-yl)phenol (HL) was synthesized and structurally characterized. HL possessed D-π-A structure and exhibited typical AIE property in THF/H2O. It was applied to selectively recognize Cu2+ through an on-off mode in THF/H2O (1/9, v/v), and the fluorescence attenuation was attributed to a paramagnetic quenching effect of Cu2+ together with the abatement of HL aggregates. Hence, the detection limit achieved was as low as 1.32 × 10-7 M. The spectroscopic and ESI-HRMS results revealed a 1 : 2 complexation ratio of Cu2+ with HL. The mechanism for sensing Cu2+ was further confirmed by performing DFT calculations. Owing to the large affinity between Cu2+ and His, the resultant CuL2 system was further used to detect His via the off-on method based on the displacement of ligands. The detection limit for His reached 5.14 × 10-8 M. Furthermore, HL was available to prepare handy indicator papers for the on-site recognition of Cu2+ and His. Confocal fluorescent imaging demonstrated that HL could sequentially respond to intracellular Cu2+ and His.


Asunto(s)
Cobre , Bases de Schiff , Bases de Schiff/química , Espectrometría de Fluorescencia , Cobre/química
3.
Materials (Basel) ; 15(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36431593

RESUMEN

Aluminum alloys and their welding structures have been widely used in aviation, aerospace, automobiles, ships, and other industrial fields. The non-uniform nature of welding structures of aluminum alloys causes intractable corrosion problems. Anodizing and subsequent sealing processes are common and effective methods to improve the corrosion resistance of welding structures. However, traditional sealing processes like hot water sealing and potassium dichromate sealing are criticized due to energy consumption or toxicity. In this work, a layered double hydroxide (LDH) sealing process with subsequent fluorinated siloxane modification is proposed to improve the corrosion resistance of the anodic oxide film of friction stir welding joints of typical aluminum alloys. The obtained sealing film with typical lamelliform structures of LDH grows well at the defects of oxidation film and also smoothens the sample surface. The hydrophobicity of the film can separate the corrosive medium from the sample surface and further enhance corrosion resistance. As a result, the corrosion current of the welded sample in 3.5 wt.% NaCl solution plummets about 3~4 orders of magnitude compared to the initial state without anodizing, indicating superior corrosion resistance brought by this method.

4.
ACS Omega ; 7(21): 18017-18026, 2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35664592

RESUMEN

A D-π-A type quinoline derivative, 2-(((4-(1, 2, 2-triphenylvinyl)phenyl)imino)methyl)quinolin-8-ol (HL), was synthesized and structurally characterized. The five-membered ring formed by the O-H···N hydrogen bond in HL contributed to the excited-state intramolecular proton transfer (ESIPT) behavior of HL, which was further verified by theoretical computations. Upon coordination with Zn2+, the hydroxyl proton in HL was removed, resulting in the inhibition of ESIPT. In the meanwhile, the formed Zn 2 L 4 complex displayed aggregation-induced emission (AIE) character in THF/H2O mixtures, which is conducive to the fluorescence enhancement in aqueous media. Structure analysis suggested that the origin of the AIE characteristic was attributed to restriction of intramolecular rotations along with the formation of J-aggregates. Based on ESIPT coupled with AIE, HL could recognize Zn(II) in aqueous media via an orange fluorescence turn-on mode. Benefitting from the AIE property, chemosensor HL was successfully applied to fabricate test strips for rapid sensing of Zn(II) ions.

5.
World J Clin Cases ; 10(12): 3729-3738, 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35647170

RESUMEN

BACKGROUND: Microvascular tissue reconstruction is a well-established, commonly used technique for a wide variety of the tissue defects. However, flap failure is associated with an additional hospital stay, medical cost burden, and mental stress. Therefore, understanding of the risk factors associated with this event is of utmost importance. AIM: To develop machine learning-based predictive models for flap failure to identify the potential factors and screen out high-risk patients. METHODS: Using the data set of 946 consecutive patients, who underwent microvascular tissue reconstruction of free flap reconstruction for head and neck, breast, back, and extremity, we established three machine learning models including random forest classifier, support vector machine, and gradient boosting. Model performances were evaluated by the indicators such as area under the curve of receiver operating characteristic curve, accuracy, precision, recall, and F1 score. A multivariable regression analysis was performed for the most critical variables in the random forest model. RESULTS: Post-surgery, the flap failure event occurred in 34 patients (3.6%). The machine learning models based on various preoperative and intraoperative variables were successfully developed. Among them, the random forest classifier reached the best performance in receiver operating characteristic curve, with an area under the curve score of 0.770 in the test set. The top 10 variables in the random forest were age, body mass index, ischemia time, smoking, diabetes, experience, prior chemotherapy, hypertension, insulin, and obesity. Interestingly, only age, body mass index, and ischemic time were statistically associated with the outcomes. CONCLUSION: Machine learning-based algorithms, especially the random forest classifier, were very important in categorizing patients at high risk of flap failure. The occurrence of flap failure was a multifactor-driven event and was identified with numerous factors that warrant further investigation. Importantly, the successful application of machine learning models may help the clinician in decision-making, understanding the underlying pathologic mechanisms of the disease, and improving the long-term outcome of patients.

6.
Int J Ophthalmol ; 14(8): 1133-1137, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34414075

RESUMEN

AIM: To explore the ocular features of corona virus disease (COVID)-19 and severe acute respiratory syndrome coronavirus (SARS-CoV)-2 detection in tears and conjunctival scrapes in non-severe COVID-19 patients. METHODS: This is a multicenter observational clinical study with no intervention conducted from Jan 25th to March 1st, 2020. Clinical data and samples of tears and conjunctival scraping were collected in consecutive laboratory-confirmed, non-severe COVID-19 patients from three hospitals. COVID-19 virus was analyzed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) kits. RESULTS: Totally 255 laboratory-confirmed, non-severe COVID-19 patients were recruited for ocular manifestation investigation. Of them, 54.9% were females, with a mean age of 49.4y. None of the patients has evidence of uveitis; 11 patients (4.3%) complained of mild asthenopia; 2 (0.8%) had mild conjunctival congestion and serous secretion. Twenty-five of them had performed tears and conjunctival scrape for COVID-19 virus detection, with 4 yield possible positive results in the nucleoprotein gene. One of them were asymptomatic with normal chest CT and positive pharyngeal swab result. CONCLUSION: Ocular manifestations are neither common nor specific in non-severe COVID-19 patients. Meanwhile, COVID-19 virus nucleotides can be detected in the tears and conjunctival scrape samples, warranting further research on the transmissibility by the ocular route.

7.
BMC Public Health ; 21(1): 45, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407275

RESUMEN

BACKGROUND: Social capital has been linked to health behaviours, but the underlying mechanism is unclear. Previous studies have found that health literacy played the role of a mediator in the relationships among social capital, individual physical activity and nutrition. But it is not clear whether eHealth literacy mediates the impact of social capital on health behaviours. Therefore, our research aimed to explore the relationships among social capital (structural and cognitive social capital), eHealth literacy, and the health behaviours of elderly people, and to analyse the mediating effect of eHealth literacy, while providing a theoretical basis for a health behaviour intervention for elderly people. METHODS: From January to February 2019, we conducted a cross-sectional survey of 1201 Chinese people aged over 60 years using the Chinese Shortened Social Capital Scale (contains two subscales of structural social capital and cognitive social capital), eHealth Literacy Scale, and Health-Promoting Lifestyle Profile. We used structural equation modelling to test a hypothetical mediation model. RESULTS: The mean scores of social capital was 72.07 (SD = 13.03), 17.24 (SD = 9.34) for eHealth literacy, and 112.23 (SD = 23.25) for health behaviours. Social capital and eHealth literacy were significantly correlated with health behaviours, and social capital and structural social capital were significantly correlated with eHealth literacy. Lastly, eHealth literacy mediated the relationship between structural social capital and health behaviours. CONCLUSIONS: eHealth literacy was an important mediating factor for elderly people's structural social capital and health behaviours. Therefore, social capital and eHealth literacy must be considered when designing and implementing health behaviour intervention programmes for elderly people.


Asunto(s)
Alfabetización en Salud , Capital Social , Telemedicina , Anciano , China , Estudios Transversales , Conductas Relacionadas con la Salud , Humanos , Encuestas y Cuestionarios
8.
Artículo en Inglés | MEDLINE | ID: mdl-32230935

RESUMEN

Background: Healthy lifestyles and health literacy are strongly associated with cognitive health in older adults, however, it is unclear whether this relationship can be generalized to health-promoting lifestyles and eHealth literacy. To date, no research has examined the interactive effect of health-promoting lifestyles and eHealth literacy on cognitive health. Objective: To examine the associations among health-promoting lifestyles, eHealth literacy, and cognitive health in older adults. Methods: Using a stratified cluster sampling method, we conducted a survey with older adults in four districts and two counties in Jinan (China). Older adults (n = 1201; age ≥ 60 years) completed our survey. We assessed health-promoting lifestyles, eHealth literacy, and cognitive health, and collected participants' sociodemographic information. Results: Health-promoting lifestyles and eHealth literacy were significantly and positively associated with cognitive health (both p < 0.01). In addition, eHealth literacy was positively associated with health-promoting lifestyles. Moreover, the interaction of health-promoting lifestyle and eHealth literacy negatively predicted cognitive health (ß = -0.465, p < 0.01). Conclusions: Health-promoting lifestyles and eHealth literacy were associated with the cognitive health of Chinese older adults, both independently and interactively. Further, eHealth literacy was associated with health-promoting lifestyles in older adults. Therefore, interventions regarding healthy lifestyles and eHealth literacy would benefit older adults.


Asunto(s)
Cognición , Alfabetización en Salud , Estilo de Vida Saludable , Telemedicina , Anciano , China , Trastornos del Conocimiento/prevención & control , Estudios Transversales , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad
9.
Reproduction ; 157(4): 345-358, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30668522

RESUMEN

Decline in successful conception decreases more rapidly after 38 years of age owing to follicular depletion and decreased oocyte quality. However, limited information is available regarding the underlying mechanism and the useful treatment. This study aimed to evaluate the effects of growth hormone supplementation on oocyte maturation in vivo in aged and young mice and to determine its effect on mitochondrial function. The influence of three different doses of recombinant human growth hormone (rhGH) (0.4, 0.8 and 1.6 mg/kg/day) for 8 weeks before ovarian stimulation was analyzed. Superovulated oocytes were released from the oviduct of 12-week-old and 40-week-old female C57BL/6J mice 14-16 h after administration of human chorionic gonadotropin. Ovarian follicle and morphological analysis and oocyte maturation parameters were then evaluated. This study is the first, to our knowledge, to report that medium- and high-dose rhGH significantly increases antral follicles in aged mice but anti-Müllerian hormone (AMH) levels. Furthermore, derived oocytes, MII-stage oocyte rate, ATP levels, mitochondrial membrane potential and frequencies of homogeneous mitochondrial distribution increased. In contrast, in both aged and young mice, the mtDNA copy numbers per oocyte were similar before rhGH administration, and upon saline administration, they did not differ significantly. We conclude that medium-dose rhGH supplementation before standard ovarian stimulation regimens improves oocyte quality in aged mice, probably by enhancing mitochondrial functionality.


Asunto(s)
Envejecimiento/fisiología , Hormona de Crecimiento Humana/administración & dosificación , Mitocondrias/fisiología , Oocitos/fisiología , Folículo Ovárico/fisiología , Proteínas Recombinantes/administración & dosificación , Animales , Hormona Antimülleriana/metabolismo , Femenino , Humanos , Técnicas de Maduración In Vitro de los Oocitos , Potencial de la Membrana Mitocondrial , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Oocitos/citología , Oocitos/efectos de los fármacos , Folículo Ovárico/citología , Folículo Ovárico/efectos de los fármacos , Inducción de la Ovulación
10.
Int J Mol Sci ; 17(9)2016 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-27626406

RESUMEN

Small GTPases play important roles in the growth, development and environmental responses of eukaryotes. Based on the genomic sequence of the straw mushroom Volvariella volvacea, 44 small GTPases were identified. A clustering analysis using human small GTPases as the references revealed that V. volvacea small GTPases can be grouped into five families: nine are in the Ras family, 10 are in the Rho family, 15 are in the Rab family, one is in the Ran family and nine are in the Arf family. The transcription of vvran1 was up-regulated upon hydrogen peroxide (H2O2) stress, and could be repressed by diphenyleneiodonium chloride (DPI), a NADPH oxidase-specific inhibitor. The number of vvran1 transcripts also increased upon cold stress. Diphenyleneiodonium chloride, but not the superoxide dismutase (SOD) inhibitor diethy dithiocarbamate (DDC), could suppress the up-regulation of vvran1 gene expression to cold stress. These results combined with the high correlations between gene expression and superoxide anion (O2(-)) generation indicated that vvran1 could be one of the candidate genes in the downstream of O2(-) mediated pathways that are generated by NADPH oxidase under low temperature and oxidative stresses.


Asunto(s)
Peróxido de Hidrógeno/farmacología , Proteínas de Unión al GTP Monoméricas/genética , Estrés Fisiológico , Volvariella/enzimología , Frío , Proteínas Fúngicas/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Humanos , Familia de Multigenes , Compuestos Onio/farmacología , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Volvariella/genética , Proteína de Unión al GTP ran/genética
11.
Pancreas ; 45(4): 546-51, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26418909

RESUMEN

OBJECTIVES: X-ray repair cross-complementing group 1 (XRCC1) gene is an important candidate gene for influencing human cancer risks. This study examined the main and interactive effect of 9 single-nucleotide polymorphisms (SNPs) (Arg194Trp, Arg280His, Arg399Gln, c.1254C>T, c.1517G>C, c.1471G>A, C310T, 539del542, and T1915C) of XRCC1 in contribution to pancreatic cancer (PC). METHODS: A total of 298 PC patients and 298 healthy controls were enrolled. Selected SNPs in XRCC1 were genotyped. The generalized multifactor dimensionality reduction method investigated gene-gene interactions. RESULTS: Single-locus analyses showed that, in the codominant model, the GO genotype of 539del542 might have a higher risk for PC (odds ratio [OR], 1.47; 95% confidence interval [95% CI], 1.05-2.08). For T1915C polymorphism, the TC and CC genotypes both had a higher risk for PC (OR, 1.76; 95% CI, 1.25-2.48; OR, 1.83; 95% CI, 1.05-3.19, respectively); and a similar result was observed in the dominant model (OR, 1.77; 95% CI, 1.28-2.46). A tendency of association between Arg280His and PC was also detected in the dominant model (OR, 0.70; 95% CI, 0.48-1.00). Furthermore, the generalized multifactor dimensionality reduction method showed that the 4-locus model was significant, involving Arg280His, 539del542, T1915C, and c.1517G>C (P < 0.05). CONCLUSIONS: Thus, XRCC1 polymorphisms may contribute to the risk of PC independently or in an interactive manner.


Asunto(s)
Proteínas de Unión al ADN/genética , Predisposición Genética a la Enfermedad/genética , Neoplasias Pancreáticas/genética , Polimorfismo de Nucleótido Simple , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Modelos Genéticos , Factores de Riesgo , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
12.
FEBS Lett ; 589(17): 2224-32, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26149212

RESUMEN

This study was aimed to investigate miR-216a expression in pancreatic cancer and determine its effects on proliferation. miR-216a was found downregulated in pancreatic cancer tissues as compared to benign pancreatic lesions. JAK2 was identified as a miR-216a gene target. Further, in vivo treatment of PANC-1 tumors with miR-216a reduced JAK2 protein levels in the tumor and reduced tumor volume. In conclusion, miR-216a may function as a tumor suppressor regulating pancreatic cancer cells by targeting the JAK/STAT pathway. Further studies with a larger number of patient samples are necessary to fully explore the diagnostic and therapeutic potential of miR-216a for pancreatic cancer.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Janus Quinasa 2/genética , MicroARNs/genética , Neoplasias Pancreáticas/genética , Regiones no Traducidas 3'/genética , Adulto , Anciano , Animales , Apoptosis/genética , Western Blotting , Línea Celular , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Humanos , Janus Quinasa 2/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
13.
Nanoscale ; 7(12): 5395-402, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25728562

RESUMEN

Monoclinic Fe3-xCrxSe4 nanostructures (0≤x≤2.5) were synthesized using a high-temperature solution chemical method. With increasing the Cr doping, the peak positions in the X-ray diffraction (XRD) patterns of Fe3-xCrxSe4 nanostructures slightly shifted to lower 2θ values due to the changes in lattice parameters. Expansions in the unit cell volumes of Fe3-xCrxSe4 nanostructures (x>0.3) may have been responsible for enhancing the ferromagnetic (FM) interaction between magnetic ions, which resulted in a significant increase in the Curie temperature (TC) from 331 K for Fe3Se4 to 429 K for FeCr2Se4, distinctly differing from the magnetic properties of the corresponding bulk materials. A room-temperature coercivity (HC) analysis showed an obvious increase from 3.2 kOe for Fe3Se4 to 12 kOe for Fe2.3Cr0.7Se4 nanostructure, but gradually decreased upon further increasing the Cr content.

14.
Zhongguo Gu Shang ; 27(3): 258-60, 2014 Mar.
Artículo en Chino | MEDLINE | ID: mdl-24974435

RESUMEN

OBJECTIVE: To evaluate the effect of lateral supramalleolar artery descending branch antidromic flap for the repair of soft tissue defects in the foot and ankle. METHODS: From May 2009 to October 2013,12 patients with soft tissue defects combined with tendon and bone exposure in the foot and ankle were treated by lateral supramalleolar artery descending branch antidromic flap for the repair of soft tissue defects in the foot and ankle, including 9 males and 3 females with an average age of 37.5 years old ranging from 19 to 58 years. Ten cases had the soft tissue defects in the dorsum of foot and 2 in the ankle. The defect area of soft tissue was from 11 cm x 9 cm to 8 cm x 5 cm. RESULTS: Twelve patients were follow-up for 3 to 12 months (averaged 7.3 months). The flaps of 9 cases were survived,the flaps edges of the other 3 cases were necrosis,and healed after dressing change. The flaps were slightly swelling without ulcer occurrence. CONCLUSION: Lateral supramalleolar artery descending branch antidromic flap can repairing the damage by one-stage operation with advantage of dissection easy,rich blood supply without sacrifice of major artery.


Asunto(s)
Traumatismos de los Pies/cirugía , Pie/cirugía , Traumatismos de los Tejidos Blandos/cirugía , Adulto , Tobillo/irrigación sanguínea , Tobillo/cirugía , Arterias/cirugía , Femenino , Pie/irrigación sanguínea , Humanos , Masculino , Persona de Mediana Edad , Colgajos Quirúrgicos , Adulto Joven
15.
Fitoterapia ; 90: 220-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23954177

RESUMEN

Five ophiobolane sesterterpenes, ophiobolins P-T, and three known compounds, 6-epi-21,21-O-dihydroophiobolin G, 6-epi-ophiobolin G and 6-epi-ophiobolin K, were isolated from the acetone extract of the endolichenic fungus Ulocladium sp. by using OSMAC method. Their structures were elucidated on the basis of spectroscopic analysis. The absolute configuration of the 18,19-diol moieties in ophiobolin Q was assigned using the Frelek's method. The cytotoxic effects on KB and HepG2 cell lines, antibacterial activity against Bacillus subtilis, methicillin-resistant Staphylococcus aureus, and Bacille Calmette-Guerin were evaluated for all isolated compounds. Ophiobolin T and 6-epi-ophiobolin G exhibited the most potent cytotoxic activity against HepG2 with IC50 of 0.24 and 0.37 µM, respectively. In antibacterial assay, ophiobolins P and T showed moderate antibacterial activity against B. subtilis and meticillin-resistant S. aureus. Ophiobolin T also displayed moderate antibacterial activity against the Bacille Calmette-Guerin strain.


Asunto(s)
Antibacterianos/farmacología , Ascomicetos/química , Bacterias/efectos de los fármacos , Productos Biológicos/farmacología , Líquenes/química , Neoplasias/tratamiento farmacológico , Sesterterpenos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Bacillus subtilis/efectos de los fármacos , Productos Biológicos/química , Productos Biológicos/uso terapéutico , Células Hep G2 , Humanos , Células KB , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium bovis/efectos de los fármacos , Sesterterpenos/química , Sesterterpenos/aislamiento & purificación
16.
J Nat Prod ; 76(8): 1448-53, 2013 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-23869482

RESUMEN

Five new hispidin derivatives, phaeolschidins A-E (1-5), as well as two known natural products, pinillidine (6) and hispidin (7), were isolated from the fruiting bodies of Phaeolus schweinitzii collected in the Tibetan Plateau. The structures of the new compounds were elucidated by spectroscopic methods. Phaeolschidins A-D (1-4) are new bishispidins. Phaeolschidin E (5) is a new class of hispidin derivative in which one pyrrolidin-2-one moiety was linked to C-3 of hispidin. The antioxidant activity of 1-7 was evaluated using three methods: the DPPH scavenging assay, the total antioxidant capacity assay, and the lipid peroxidation assay. Hispidin showed the strongest antioxidant activity of all tested compounds. This is the first report of secondary metabolites from the fungus P. schweinitzii.


Asunto(s)
Agaricales/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Pironas/aislamiento & purificación , Pironas/farmacología , Antioxidantes/química , Compuestos de Bifenilo/farmacología , Cuerpos Fructíferos de los Hongos/química , Peroxidación de Lípido , Estructura Molecular , Oxidación-Reducción , Picratos/farmacología , Pironas/química , Tibet
17.
J Nat Prod ; 76(1): 45-50, 2013 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-23294419

RESUMEN

Five novel perhydrobenzannulated 5,5-spiroketal sesquiterpenes, namely, pleurospiroketals A-E (1-5), were isolated from the culture of the edible mushroom Pleurotus cornucopiae. Pleurospiroketals D (4) and E (5) were obtained as an isomeric mixture with a ratio of 5:4. Their structures were established by NMR, X-ray single-crystal diffraction, and CD data analysis. Pleurospiroketals A-E (1-5) are sesquiterpenoids with a unique benzannulated 5,5-spiroketal skeleton. Compounds 1-3 showed inhibitory activity against nitric oxide production in lipopolysaccharide-activated macrophages with IC(50) values of 6.8, 12.6, and 20.8 µM, respectively.


Asunto(s)
Furanos/aislamiento & purificación , Pleurotus/química , Sesquiterpenos/aislamiento & purificación , Compuestos de Espiro/aislamiento & purificación , Animales , Cristalografía por Rayos X , Furanos/química , Furanos/farmacología , Células HeLa , Humanos , Concentración 50 Inhibidora , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Conformación Molecular , Estructura Molecular , Óxido Nítrico/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/farmacología , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Estereoisomerismo
18.
Org Lett ; 14(14): 3672-5, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22769974

RESUMEN

Eryngiolide A (1), the first member of C20 diterpenoids with the skeleton deriving from a cyclododecane core fused with two γ-lactone units, was isolated from the solid culture of the edible mushroom Pleurotus eryngii. The structure of 1 was elucidated by extensive analysis of NMR spectra. Compound 1 exhibited moderate cytotoxicity against two human cancer lines in vitro.


Asunto(s)
Agaricales/química , Diterpenos/química , Pleurotus/química , Línea Celular Tumoral , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular
19.
Huan Jing Ke Xue ; 33(4): 1272-7, 2012 Apr.
Artículo en Chino | MEDLINE | ID: mdl-22720577

RESUMEN

Mine tailings in Xiangsi Valley, Tongling, China, is a typical skarn-type tailing with high contents of carbonates. This study designed dynamic leaching experiments to investigate the efficiency of this tailing under the acid mine drainage treatment. During 80 d trial period, the physical and chemical properties of influents were fixed and the effluents were monitored. After the trial, the speciation of Fe, Cu and Zn in solid was analyzed. The results showed that during the trial period, pH value maintained above 7.5. Moreover, the concentrations of Cu, Zn, Fe ions in effluents kept below 0.1, 0.4 and 1 mg x L(-1), respectively. In addition, the permeability coefficient of experimental column kept decreasing during the experimental period (from 0.23 cm x s(-1) to 0.10 cm x s(-1)). Five-step sequential extraction method was employed to study the distribution of elements at different depths. The results showed that Cu2+, Zn2+ were removed mainly through sorption and precipitation. This study indicates that Tongling skarn mine tailings have strong acid neutralization as well as heavy metal binding capacities. Therefore, the authors suggest that this mine tailing, which used to be waste, has a potential in AMD control and treatment.


Asunto(s)
Residuos Industriales/prevención & control , Hierro , Metales Pesados/aislamiento & purificación , Minería , Eliminación de Residuos Líquidos/métodos , Ácidos , China , Simulación por Computador , Concentración de Iones de Hidrógeno , Contaminantes del Suelo/aislamiento & purificación
20.
Huan Jing Ke Xue ; 33(1): 293-8, 2012 Jan.
Artículo en Chino | MEDLINE | ID: mdl-22452225

RESUMEN

In this study, with rape straw as carbon source, anaerobic batch experiments were executed to investigate the effect of Zn (II) on the activity of sulphate reducing bacteria (SRB) in the microbial treatment of simulative acid mine drainage (AMD). The results showed that during the 60 experimental days, when initial Zn2+ concentrations were in the range of 73.7 to 196.8 mg x L(-1), SRB had high culturalbility. At the end of these experiments, pH values rose from initial 5.0 to neutral, about 96% of sulphate was reduced and the concentrations of Zn2+ reduced to 0.05 mg x L(-1). The results of Tessier sequential extraction, field emission scanning electron microscope (FE-SEM) and X-ray diffraction(XRD) showed that Zn was found to be fixed through forming organic and sulphide (mainly sphalerite) compounds. For the experiment with high Zn2+ concentration (262.97 mg x L(-1)), at the end of experiments, pH values dropped from initial 5.0 to 4.0, only 27% of sulphate was only reduced and the concentrations of Zn2+ kept in high range (25 mg x L(-1)), the activity of SRB significantly inhibited. This study indicated that: (1) Rape straw can be used as slow-release carbon source for long-term anaerobic AMD treatment; (2) Rape straw can decrease the toxicity of Zn2+ to SRB through adsorption; (3) In anaerobic AMD treatment system, Zn can be fixed by sulphide minerals with mediation of SRB.


Asunto(s)
Minería , Bacterias Reductoras del Azufre/metabolismo , Eliminación de Residuos Líquidos/métodos , Zinc/farmacología , Ácidos , Anaerobiosis , Biodegradación Ambiental , Brassica rapa/química , Carbono/metabolismo , Concentración de Iones de Hidrógeno , Residuos Industriales , Metales Pesados/aislamiento & purificación , Metales Pesados/metabolismo , Tallos de la Planta/química , Bacterias Reductoras del Azufre/crecimiento & desarrollo
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