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1.
Ecotoxicol Environ Saf ; 249: 114356, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508799

RESUMO

Lead (Pb2+) pollution in the soil sub-ecosystem has been a continuously growing problem due to economic development and ever-increasing anthropogenic activities across the world. In this study, the photosynthetic performance and antioxidant capacity of Triticeae cereals (rye, wheat and triticale) were compared to assess the activities of antioxidants, the degree of oxidative damage, photochemical efficiency and the levels of photosynthetic proteins under Pb stress (0.5 mM, 1 mM and 2 mM Pb (NO3)2). Compared with triticale, Pb treatments imposed severe oxidative damage in rye and wheat. In addition, the highest activity of major antioxidant enzymes (SOD, POD, CAT, and GPX) was also found to be elevated. Triticale accumulated the highest Pb contents in roots. The concentration of mineral ions (Mg, Ca, and K) was also high in its leaves, compared with rye and wheat. Consistently, triticale showed higher photosynthetic activity under Pb stress. Immunoblotting of proteins revealed that rye and wheat have significantly lower levels of D1 (photosystem II subunit A, PsbA) and D2 (photosystem II subunit D, PsbD) proteins, while no obvious decrease was noticed in triticale. The amount of light-harvesting complex II b6 (Lhcb6; CP24) and light-harvesting complex II b5 (Lhcb5; CP26) was significantly increased in rye and wheat. However, the increase in PsbS (photosystem II subunit S) protein only occurred in wheat and triticale exposed to Pb treatment. Taken together, these findings demonstrate that triticale shows higher antioxidant capacity and photosynthetic efficiency than wheat and rye under Pb stress, suggesting that triticale has high tolerance to Pb and could be used as a heavy metal-tolerant plant.


Assuntos
Chumbo , Estresse Oxidativo , Complexo de Proteína do Fotossistema II , Secale , Poluentes do Solo , Triticale , Triticum , Ecossistema , Chumbo/toxicidade , Secale/efeitos dos fármacos , Secale/enzimologia , Triticale/efeitos dos fármacos , Triticale/enzimologia , Triticum/efeitos dos fármacos , Triticum/enzimologia , Poluentes do Solo/toxicidade
2.
Phys Chem Chem Phys ; 18(10): 7019-22, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26892492

RESUMO

Single-crystalline 1,2,3,4,5-pentaphenyl-1,3-cyclopentadiene (PPCP) microrods were prepared by a facile solution process. The PPCP microrods with smooth surfaces could absorb excitation light and propagate the photoluminescence (PL) emission. They showed excellent properties in the low optical loss of a single rod and feasible transfer between neighboring rods. Moreover, PPCP displayed typical aggregation-induced emission enhancement (AIEE) characteristics in the solution state.

3.
J Nanosci Nanotechnol ; 15(8): 6015-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26369189

RESUMO

2D microstructures of N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4'-di-amine (NPB) have been prepared by a facile solution method and fully characterized. The as-prepared NPB microsheets have well-defined shapes and very smooth surfaces, and are ideal building blocks for 2D optical waveguides. The results indicate that the optic losses within NPB microsheets are closely related to the direction of propagation, and the shape of microsheets can change the direction of waveguiding light. Such 2D optical waveguides may have potential applications in future miniaturized light-based circuits serve as interconnectors different from 1 D optical waveguides.


Assuntos
Benzidinas/química , Difenilamina/análogos & derivados , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Ressonância de Plasmônio de Superfície/instrumentação , Benzidinas/efeitos da radiação , Cristalização/métodos , Difenilamina/química , Difenilamina/efeitos da radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Teste de Materiais , Tamanho da Partícula , Espalhamento de Radiação , Semicondutores , Propriedades de Superfície
4.
Phys Chem Chem Phys ; 14(38): 13180-6, 2012 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22914761

RESUMO

The synthesis of hybrid nanostructures with controlled size, shape, composition and morphology has attracted increasing attention due to the fundamental and applicable interest. Here, we demonstrate the synthesis and optical properties of hierarchical CdSe-Au hybrid nanostructures with zinc blende (ZB) CdSe nanocrystals (NCs). For 3.5 nm ZB CdSe NCs, one Au cluster was deposited on each CdSe NC. Nevertheless, several Au clusters were selectively deposited on the apexes of 5 nm and 8 nm ZB CdSe NCs, resulting from the different reactivity of crystal facets. Furthermore, hierarchical CdSe-Au nanostructures with complex morphology were organized with the isolated CdSe-Au hybrid NCs by the coalescence of Au domains on the CdSe-Au hybrid NCs. UV-Vis spectra revealed a red tail upon the deposition of Au clusters. The chemical joint of Au on CdSe NCs was further confirmed by fluorescence quenching. The optical limiting performance of CdSe-Au hybrid NCs dispersed in toluene was investigated at 532 nm using a Nd:YAG laser with the pulse width of 8 ns.

5.
Gastroenterol Res Pract ; 2022: 5288075, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311294

RESUMO

Aim: To explore the correlations between the expression of zinc finger protein 521 (ZNF521) with immune invasion and prognosis of gastric cancer. Methods: Expression of ZNF521 was examined by immunohistochemistry in gastric cancer cases. Kaplan-Meier plotter was used to determine the relationships between ZNF521 and prognosis. TIMER and GEPIA were used to analyze the correlation between ZNF521 expression and gene markers of immune cell infiltration. Results: The expression of ZNF521 was up-regulated in gastric cancer samples. Kaplan-Meier analysis indicated that higher expression of ZNF521 was associated with poor prognosis. The expression of ZNF521 was correlated with infiltrating levels of CD4+ T and CD8+ T cells, macrophages, neutrophils, and dendritic cells in gastric cancer, which also correlated with diverse immune marker sets. Conclusions: ZNF521 is correlated significantly with immune cell infiltration and is a valuable biomarker for prognosis in gastric cancer.

6.
Front Oncol ; 12: 1000719, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36591467

RESUMO

The incidence and mortality of gastric cancer ranked 5th and 3rd worldwide, respectively, in 2018, and the incidence of gastroesophageal junction adenocarcinoma increased over the past 40 years. Radical resection and lymph node dissection is the preferred treatment for gastric cancer. Proximal gastrectomy or total gastrectomy is usually performed for gastroesophageal junction adenocarcinoma and upper gastric cancer. Owing to the resection of the cardia structures, the incidence of reflux esophagitis increases significantly after proximal gastrectomy and total gastrectomy, resulting in poor postoperative quality of life. To reduce the incidence of reflux esophagitis and improve patients' postoperative quality of life, various methods to preserve the function of the cardia or to perform anti-reflux reconstruction have emerged. In this manuscript, we systematically introduced the advantages and problems of various anti-reflux anastomotic method after proximal gastrectomy, and cardia-preserving gastrectomy including endoscopic resection (ER), local gastrectomy by gastroscopy combined with laparoscopy, segmental gastrectomy, subtotal gastrectomy, and cardia-preserving radical gastrectomy. Cardia-preserving radical gastrectomy has the advantage of more thorough lymph node dissection and wider indications than those for subtotal gastrectomy. However, the clinical efficacy of cardia-preserving radical gastrectomy requires verification in prospective and controlled clinical trials. Cardia-preserving radical gastrectomy is a promising approach as one of the more reasonable anti-reflux surgeries.

7.
Food Chem ; 286: 260-267, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827604

RESUMO

Coriandrum sativum L. is well known around the world because of its food and medicine uses. The main bioactive constituents in C. sativum are essential oil, fatty acids, tocol, sterol and carotenoids, their yields and chemical compositions being influenced by genotype, variety, planting season, ecotype, planting condition, growth stage, plant part, harvesting time, extracting process and other factors. Coriander and its different extracts possess varying degrees of antioxidative and antimicrobial activities on account of different active constituents. The general usages, chemical compositions and bioactivities of coriander are summarized in this review, along with safety considerations.


Assuntos
Coriandrum/química , Óleos Voláteis/química , Compostos Fitoquímicos/química , Anti-Infecciosos/química , Antioxidantes/química , Carotenoides/química , Coriandrum/metabolismo , Ácidos Graxos/química , Frutas/química , Frutas/metabolismo , Esteróis/química
8.
Zhongguo Zhong Yao Za Zhi ; 33(19): 2182-4, 2008 Oct.
Artigo em Zh | MEDLINE | ID: mdl-19166001

RESUMO

OBJECTIVE: To establish a high performance liquid chromatographic (HPLC) amalgamated to double UV waves method for simultaneous determination of loganin and paeonol in Liuwei Dihuang pills. METHOD: A HPLC method was developed. The separation was carried out on a Agilent Zorbax SB C18 column (5 microm, 4.6 mm x 250 mm). The mobile phase consisted of water (A) and acetonitrile (B) with linear linear gradient elution [0-8 min, (B) from 1% to 12%; 8-21 min, B keep 12%; 21-40 min, (B) from 12% to 90%; 40-50 min, B keep 90% for 10 min]. The detection was Photodiode Array with the detection wavelengths were at 236 nm and 274 nm. The column temperature being 30 degrees C and the flow rate was 1.0 mL min(-1). Extracting the chromatergraph from 274 nm and 236 nm, we amalgamated the two chromatographs by matlab programmed. RESULT: The calibration curves of loganin and paeonol were linear in the ranges of 0.0362-1.09 microg (r =0. 9998) and 0.0450-1.35 microg (r =0.9998), respectively. The average recoveries of loganin and paeonol were 97.3% (RSD 1.4 %) and 103.0% (RSD 1.9%), respectively. Three different batches of Liuwei Dihuang pills were determined with this method. CONCLUSION: This is a more convenient, reasonable and credible quality control method for the traditional Chinese medicine.


Assuntos
Acetofenonas/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Iridoides/química , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
9.
Artigo em Inglês | MEDLINE | ID: mdl-12167996

RESUMO

To obtain a thromblytic agent with high efficacy and specifity, we have engineered a recombinant chimeric plasminogen activator SZ51Hu-scuPA, which was composed of a humanized monoclonal antibody (SZ51Hu) directed against activated human platelets and a single-chain urokinase (scuPA). The cDNA sequence encoding scuPA was fused through 5' end to 3' end of the CH(3) of SZ51Hu heavy-chain sequence in the expression vector alphalys30(alphalys30-SZ51VH/Hu-scuPA) by PCR. This construct was transfected into a murine myeloma line secreting SZ51Hu light chain with Lipofectin reagent and three lines which showed stable integration and high level expression with concentration of 5 mg/L in supernatant, were selected in the end. Purified SZ51Hu-scuPA migrated as a 160 kD band on non-reduced SDS/PAGE and had the same characteristic of binding to the activated platelets compared with its parent murine antibody molecule SZ51 by Western-blot analysis. The fibrinolytic activity of purified products was 39 000 IU/mg. Thus, by recombinant techniques, an expressed fusion protein was capable of specific binding to activated platelets and plasminogen activation. These observations laid a solid foundation for further study of targeting of thrombolysis in vitro and in vivo.

10.
Sci Rep ; 4: 5998, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25104467

RESUMO

Klockmannite copper selenide nanosheets (CuSe NSs) are synthesized by a facile microwave-assisted method and fully characterized. The nanosheets have smooth surface and hexagonal shape. The lateral size is 200-500 nm × 400-800 nm and the thickness is 55 ± 20 nm. The current-voltage characteristics of CuSe NS films show unique Ohmic and high-conducting behaviors, comparable to the thermally-deposited gold electrode. The high electrical conductivity of CuSe NSs implies their promising applications in printed electronics and nanodevices. Moreover, the local electrical variation is observed, for the first time, within an individual CuSe NS at low bias voltages (0.1 ~ 3 V) by conductive atomic force microscopy (C-AFM). This is ascribed to the quantum size effect of NS and the presence of Schottky barrier. In addition, the influence of the molar ratio of Cu(2+)/SeO2, reaction temperature, and reaction time on the growth of CuSe NSs is explored. The template effect of oleylamine and the intrinsic crystal nature of CuSe NS are proposed to account for the growth of hexagonal CuSe NSs.

11.
PLoS One ; 8(3): e59421, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23527193

RESUMO

OBJECTIVE: A meta-analysis was applied to evaluate the associations between tumor necrosis factor-α (TNF-α) -308G>A (rs1800629) polymorphism and type 2 diabetes mellitus (T2DM). METHODS: Hardy-Weinberg equilibrium (HWE) was employed to test genetic equilibrium among the genotypes of the selected literature. Power analysis was performed with the Power and Sample Size Calculation (PS) program. A fixed or random effect model was used on the basis of heterogeneity. Publication bias was quantified and examined with the Begg's funnel plot test and Egger's linear regression test. The meta-analysis was performed with Review Manager 5.1 and Stata 11.0. RESULTS: There were 10 studies including 1425 T2DM patients and 1116 healthy control subjects involved in this meta-analysis. No significant publication bias was found in the studies. The pooled ORs (95% CIs) for TNF-α -308G>A of A vs. G allele and GA+AA vs. GG genotype were 1.63 (1.17-2.25) and 1.47 (1.17-1.85), respectively. CONCLUSION: This meta-analysis result suggested that TNF-α -308G>A polymorphism was strongly associated with T2DM risk, and A allele at this locus might be a susceptibility allele for the development of T2DM in Han Chinese population.


Assuntos
Povo Asiático/genética , Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleotídeo Único/genética , Fator de Necrose Tumoral alfa/genética , Estudos de Associação Genética , Genótipo , Humanos , Modelos Lineares , Modelos Genéticos , Razão de Chances , Viés de Publicação
12.
Ying Yong Sheng Tai Xue Bao ; 20(1): 143-8, 2009 Jan.
Artigo em Zh | MEDLINE | ID: mdl-19449578

RESUMO

A field experiment was conducted to study the characteristics of paddy field nitrogen (N) leakage and runoff under rice-duck farming (MRD), conventional farming (MR), and conventional farming with flooding (CK). Comparing with that under MR, the paddy field under MRD had a notable decrease of N (especially NO3- -N) concentration in its leaked liquid; but this concentration was tended to be increased, compared with that under CK. After 7-9 days of fertilization, the NH4+ -N and NO3- -N concentrations in paddy field surface water were higher under MRD than under MR. However, owing to the no draining and the higher band, the paddy field under MRD had a notable reduction of drainage, resulting in a marked decrease of N runoff than that under MR. Comparing with MR, the paddy field under MRD had an addition of nitrogen supply from duck dung, a reduction of N leakage and runoff, a lesser application of chemical nitrogen fertilizer, and more nitrogen uptake by rice plant. Both the reduction of N input and that of N output in rice-duck farming system were nearly equal in quantity.


Assuntos
Agricultura/métodos , Patos/crescimento & desenvolvimento , Nitrogênio/análise , Oryza/crescimento & desenvolvimento , Solo/análise , Animais , China , Monitoramento Ambiental , Poluição Ambiental/prevenção & controle , Fertilizantes , Compostos de Amônio Quaternário/análise
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