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1.
Angew Chem Int Ed Engl ; : e202405798, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659324

RESUMO

RuO2 has been considered as the most likely acidic oxygen evolution reaction (OER) catalyst to replace IrO2, but its performance, especially long-term stability under harsh acidic conditions, is still unacceptable. Here, we propose a grain boundary (GB) engineering strategy by fabricating the ultrathin porous RuO2 nanosheet with abundant of grain boundaries (GB-RuO2) as an efficient acid OER catalyst. The involvement of GB induces significant tensile stress and creates an unsaturated coordination environment, effectively optimizing the adsorption of intermediates and stabilizing active site structure during OER process. Notably, the GB-RuO2 not only exhibits a low overpotential (η10=187 mV) with an ultra-low Tafel slope (34.5 mV dec-1), but also steadily operates for over 550 h in 0.1 M HClO4. Quasi in situ/operando methods confirm that the improved stability is attributed to GB preventing Ru dissolution and greatly inhibiting the lattice oxygen oxidation mechanism (LOM). A proton exchange membrane water electrolysis (PEMWE) using the GB-RuO2 catalyst operates a low voltage of 1.669 V at 2 A cm-2 and operates stably for 100 h at 100 mA cm-2.

2.
Angew Chem Int Ed Engl ; : e202408758, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899532

RESUMO

Electrochemical nitrate reduction reaction (NitRR) uses nitrate from wastewater, offering a hopeful solution for environmental issues and ammonia production. Yet, varying nitrate levels in real wastewater greatly affect NitRR, slowing down its multi-step process. Herein, a multi-strategy approach was explored through the design of ordered mesoporous intermetallic AuCu3 nanocorals with ultrathin Au skin (meso-i-AuCu3@ultra-Au) as an efficient and concentration-versatile catalyst for NitRR. The highly penetrated structure, coupled with the compressive stress exerted on the skin layer, not only facilitates rapid electron/mass transfer, but also effectively modulates the surface electronic structure, addressing the concentration-dependent challenges encountered in practical NitRR process. As expected, the novel catalyst demonstrates outstanding NitRR activities and Faradaic efficiencies exceeding 95% across a real and widespread concentration range (10-2000 mM). Notably, its performance at each concentration matched or exceeded that of the best-known catalyst designed for that concentration. Multiple operando spectroscopies unveiled the catalyst concurrently optimized the adsorption behavior of different intermediates (adsorbed *NOx and *H) while expediting the hydrogenation steps, leading to an efficient overall reduction process. Moreover, the catalyst also displays promising potential for use in ammonia production at industrial-relevant current densities and in conceptual zinc-nitrate batteries, serving trifunctional nitrate conversion, ammonia synthesis and power supply.

3.
Anal Bioanal Chem ; 415(29-30): 7103-7115, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37837540

RESUMO

1,5-anhydroglucitol (1,5-AG) is of considerable clinical relevance as a biochemical marker of glucose metabolism in the assessment and monitoring of diabetes. Herein, a simple colorimetric biosensor was constructed for the identification and detection of 1,5-AG by using pyranose oxidase (PROD) enzyme cascaded with reduced graphene oxide/persimmon tannin/Pt@Pd (RGO-PT/Pt@Pd NPs) nanozyme. The as-prepared RGO-PT/Pt@Pd NPs had excellent peroxidase-like activity and can be applied as a nanozyme. First, PROD enzyme reacts with the target 1,5-AG, decomposing 1,5-AG into 1,5-anhydrofuctose (1,5-AF) and H2O2. At this point, the highly catalytic RGO-PT/Pt@Pd NPs nanozyme produces a cascade with PROD enzyme which catalyzes the decomposition of H2O2 to produce O2. This in turn oxidizes the substrate 3,3',5,5'-tetramethylbenzidine (TMB) and produces a color change in the solution. Finally, the detection of 1,5-AG was achieved by measuring the absorption peak at 652 nm with an ultraviolet visible (UV-vis) spectrophotometer. Under optimal conditions, the linear operating range of the 1,5-AG enzyme cascade colorimetric sensor was 1.0-100.0 µg/mL, and the limit of detection (LOD) was 0.81 µg/mL. The proposed colorimetric biosensor was successfully applied to detect 1,5-AG in spiked human serum samples with the recoveries of 97.2-103.9% and RSDs of 1.94-4.48%. It provides a promising developmental assay for clinical detection of 1,5-AG.


Assuntos
Diospyros , Peróxido de Hidrogênio , Humanos , Peróxido de Hidrogênio/química , Diospyros/metabolismo , Colorimetria , Taninos , Citocromo P-450 CYP2B1 , Peroxidase/química
4.
Fish Shellfish Immunol ; 120: 280-286, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34838703

RESUMO

The study explored on the effects of dietary 0.4% dandelion extract on the growth performance, serum biochemical parameters, liver histology and the expression levels of immune and apoptosis-related genes in the head kidney and spleen of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀) at different feeding period. The results showed that the weight gain rate (WGR) of the hybrid grouper were significantly increased at the second and fourth weeks (P < 0.05), but there was no significant difference in WGR at the eighth week (P > 0.05). Compared with the control group, dietary dandelion extracts supplementation improve lipid metabolism, reduce lipid accumulation in liver and maintain normal liver histology at the second and fourth weeks. At the end of the second week, the relative expression levels of antioxidant related genes (MnSOD, GPX and GR) in the head kidney of hybrid grouper fed with dandelion extract increased significantly; at the end of week 4 and week 8, the relative expression levels of antioxidant related genes other than MnSOD did not change significantly. However, in the spleen of hybrid grouper, the expression of these antioxidant genes showed the opposite trend. At the end of the eighth week, dietary dandelion extract supplementation significantly increased the expression of inflammatory response related genes in head kidney of hybrid grouper, but showed the opposite trend in spleen. In conclusion, the short-term (2 or 4 weeks) application of 0.4% dandelion extract in feed had the effects of growth improvement, liver protection and immune stimulation on hybrid grouper due to its antioxidant and anti-inflammatory activities. The beneficial effect of dandelion extract on hybrid grouper was time-dependent, and its action time on different immune organs of hybrid grouper was not synchronous.


Assuntos
Bass , Extratos Vegetais , Taraxacum , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Apoptose , Bass/genética , Bass/crescimento & desenvolvimento , Bass/imunologia , Suplementos Nutricionais , Hibridização Genética , Fígado , Extratos Vegetais/farmacologia , Taraxacum/química
5.
J Transl Med ; 19(1): 210, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001131

RESUMO

BACKGROUND: As a significant cause of malignancy mortality, gastric carcinoma (GC) has been well documented to be an often-fatal diagnosis. Despite the limitations of effective therapy, immunotherapy has emerged as a promising therapeutic approach capable of killing cancer cells via the immune system. The current study was conducted to investigate the effect of cytokine C-C motif chemokine ligand 21 (CCL21) on GC progression through the metastasis-associated lung adenocarcinoma transcript 1/serine arginine-rich splicing factor 1/mammalian target of rapamycin (MALAT1/SRSF1/mTOR) axis. METHODS: Bioinformatics analysis was conducted to identify the key genes associated with GC and to subsequently predict their downstream genes. The effect of CCL21, MALAT1, and SRSF1 on the malignant phenotypes and epithelial-mesenchymal transition (EMT) of SGC-7901 and MGC-803 cells in-vitro and the tumorigenesis of SGC-7901 and MGC-803 cells in-vivo were assessed by expression determination and plasmid transfection. Additionally, RNA pull-down and RNA binding protein immunoprecipitation experiments were performed to determine the MALAT1-microRNA-202-3p (miR-203-3p) interaction and miR-202-3p-SRSF1 interaction followed by the analysis of their effect on the mTOR pathway. RESULTS: CCL21 was identified as a key GC immune gene. Overexpressed CCL21, MALAT1, and SRSF1 along with poorly expressed miR-202-3p were identified in the GC cells. CCL21 induced the MALAT1 expression in a time- and dose-dependent manner. Functionally, MALAT1 targeted miR-202-3p but upregulated SRSF1 and activated mTOR. Crucially, evidence was obtained indicating that CCL21 promoted both the malignant phenotypes and EMT of SGC-7901 and MGC-803 cells in-vitro and the tumorigenesis of SGC-7901 and MGC-803 cells in-vivo by increasing the MALAT1-induced upregulation of SRSF1. CONCLUSIONS: Taken together, the key observations of our study provide evidence that CCL21 enhances the progression of GC via the MALAT1/SRSF1/mTOR axis, providing a novel therapeutic target for the treatment of GC.


Assuntos
Carcinoma , MicroRNAs , RNA Longo não Codificante , Linhagem Celular Tumoral , Quimiocina CCL21 , Quimiocinas , Regulação Neoplásica da Expressão Gênica , Humanos , Ligantes , MicroRNAs/genética , RNA Longo não Codificante/genética , Fatores de Processamento de Serina-Arginina , Neoplasias Gástricas , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
6.
Fish Shellfish Immunol ; 119: 11-18, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34530079

RESUMO

The study explored on the effect of dietary compound plant extract supplementation on the growth performance, serum biochemical indicators, liver and intestinal morphological and gene expression levels in the head kidney and spleen of the hybrid grouper (Epinephelus lanceolatusâ™‚× Epinephelus fuscoguttatus♀). The compound plant extracts (BDG) was a mixture of Bupleurum edulis extract, dandelion extract and Ginkgo biloba extract in a ratio of 1:4:1. Basal diets supplemented with BDG at 0, 0.75, 1.5, 3 and 6 g/kg were fed hybrid grouper for 8 weeks. The results showed that dietary 0.75 and 1.5 g/kg BDG supplementation could significantly increase the WGR and SGR of hybrid grouper (P < 0.05). And dietary 0.75 g/kg BDG could also significantly decrease serum aspartate aminotransferase, glucose and lactate dehydrogenase in hybrid grouper (P < 0.05). Dietary BGD supplementation protected the integrity of liver and intestinal morphological structure, reduced the accumulation of liver fat. Dietary BDG supplementation might enhance the immunity of hybrid grouper by regulating the expression of antioxidant and inflammation-related genes in head kidney and spleen of hybrid grouper. Our study demonstrated that the growth promoting effect of Bupleurum extract, dandelion extract and Ginkgo biloba extract in the ratio of 1:4:1 as a compound feed additive was better than any of them as a feed additive alone, and the dosage was less. The optimal additive dosage of BDG was 0.75 g/kg in hybrid grouper diets.


Assuntos
Bass , Ração Animal/análise , Animais , Bass/genética , Dieta/veterinária , Suplementos Nutricionais , Expressão Gênica , Intestinos , Fígado , Extratos Vegetais/farmacologia
7.
Fish Shellfish Immunol ; 98: 611-618, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31533081

RESUMO

For many years, Ginkgo biloba has been used as a traditional Chinese medicine because of its antioxidant, anti-inflammatory and hepatoprotective effects. The present study aimed to investigate the effects of dietary Ginkgo biloba leaf extract (GBLE) supplementation on immune response, intestinal morphology, antioxidant ability and tight junction proteins mRNA expression of hybrid groupers fed high lipid diets. Basal diets supplemented with GBLE at 0, 0.50, 1.00, 2.00, 4.00 and 10.00 g/kg were fed to hybrid grouper for 8 weeks. The study showed that dietary GBLE supplementation significantly improved immune ability by increasing plasma complement 3, complement 4 and Immunoglobulin M content. Dietary supplementation of 0.50-2.00 g/kg GBLE improved intestinal morphology and increased the expression of zonula occludens 1, zonula occludens 2, zonula occludens 3, occludin and claudin 3a. Dietary supplementation of 0.50-2.00 g/kg GBLE improved antioxidant ability by increasing activities and expressions of glutathione peroxidase, catalase and glutathione reductase, suppressed inflammatory by increasing expression of interleukin 10, transforming growth factor ß1 and target of rapamycin, and decreased apoptotic responses by reducing the expression of caspase 3, caspase 8 and caspase 9 in the intestine of hybrid grouper fed high lipid diets. This study indicated that dietary GBLE supplementation was clearly beneficial for intestinal health and immunity in hybrid groupers fed high lipid diets and it could be used as a functional feed additive in aquaculture to promote the application of high lipid diets.


Assuntos
Antioxidantes/metabolismo , Bass/imunologia , Expressão Gênica , Imunidade Inata/efeitos dos fármacos , Intestinos/anatomia & histologia , Extratos Vegetais/metabolismo , Proteínas de Junções Íntimas/genética , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Ginkgo biloba , Intestinos/efeitos dos fármacos , Lipídeos/análise , Extratos Vegetais/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Proteínas de Junções Íntimas/metabolismo
8.
Fish Shellfish Immunol ; 98: 843-852, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31756454

RESUMO

The purpose of the present study was to explore the impaired anti-bacteria ability in immune organs and immune systems of obscure puffer induced by chronic dietary phosphorus (P) deficiency. Fish were fed diets supplemented with 6 g/kg P (P6) and 0 g/kg P (P0) respectively for 15 weeks, and lower final body weight, feed intake, weight gain, whole body P content and bone P content were observed in fish fed P0 diet (P < 0.05). Then the fish were continued to feed for 3 weeks and intraperitoneal injection with PBS (P6+PBS) and Aeromonas hydrophila (A.hydrophila) (P6 + A.hydrophila and P0 + A.hydrophila), and sampled at 3, 6, 12 and 24 h. The results showed that dietary P deficiency lowered survival rate, total hemocyte count, whereas enhanced ROS production and apoptosis rate of obscure puffer compared to the 6 g/kg P supplemented group after infection. Moreover, compared to the P sufficient group, puffer fish fed P deficient diet decreased the expressions of antioxidant genes catalase (cat) and glutathione reductase (gr), immune-related genes toll-like receptor 2 (tlr-2) and anti-inflammatory factors transforming growth factor ß1 (tgf-ß1) and interleukin 11 (il-11) while increased pro-inflammatory cytokines tumor necrosis factor α (tnf-α), interleukin 1ß (il-1ß) and interleukin 8 (il-8) in head kidney post-infection. In addition, dietary P deficiency decreased the hepatic gene expressions of anti-apoptotic factor B-cell lymphoma 2 (bcl-2) and bax-inhibitor 1 (bi-1), accompanied by increasing the mRNA expressions of pro-apoptotic factor caspase 3, caspase 8 and caspase 9 compared to the P sufficient group after A.hydrophila infection. In conclusion, dietary P deficiency impaired the anti-bacteria function of the immune system as well as immune organs by increasing oxidative stress and aggravating the inflammatory response and apoptosis in obscure puffer under the A.hydrophila challenge.


Assuntos
Antioxidantes/metabolismo , Fosfatos de Cálcio/metabolismo , Doenças dos Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , Takifugu/imunologia , Aeromonas hydrophila/fisiologia , Ração Animal/análise , Animais , Fosfatos de Cálcio/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Distribuição Aleatória
9.
Chembiochem ; 20(5): 727-733, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30452106

RESUMO

Intracellular delivery and endosomal release of antisense oligonucleotides remain a significant challenge in the development of gene-targeted therapeutics. Previously, noncovalently cyclized TAT peptide (Cyc-TAT), in which the final ring-closing step is accomplished by hybridization of two short complementary γPNA segments, has been proven more efficient than its linear analogues at entering cells. As Cyc-TAT also readily accommodates a binding site, that is, an overhanging γPNA sequence, for codelivery of functional nucleic acid probes into cells, we were able to demonstrate that the overhang-Cyc-TAT penetrated into A549 cells when carrying an anti-telomerase γPNA that specifically reduced telomerase activity by over 97 %. Herein, we report that the cyclized TAT(FAM) can escape endosomes much more efficiently than the linear TAT(FAM) after LED illumination (490 nm). Based on this observation, the endosomal release of overhang-Cyc-TAT(FAM)/anti-telomerase γPNA complex can be greatly enhanced by photoactivation, thus shortening cell treatment time from 60 to 3 h, while keeping the same high efficiency in inhibiting telomerase activity inside A549 cells.


Assuntos
Endossomos/metabolismo , Produtos do Gene tat/metabolismo , Oligonucleotídeos Antissenso/metabolismo , Peptídeos/metabolismo , Tionucleotídeos/metabolismo , Células A549 , Ciclização , Citosol/metabolismo , Humanos
10.
Mod Pathol ; 32(6): 741-754, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30666052

RESUMO

Programmed cell death protein 1/programmed cell death protein ligand1 (PD-1/PD-L1) interaction is an important immune checkpoint targeted by anti-PD-1/PD-L1 immunotherapies. However, the observed prognostic significance of PD-1/PD-L1 expression in diffuse large B-cell lymphoma treated with the standard of care has been inconsistent and even contradictory. To clarify the prognostic role of PD-1/PD-L1 expression and interaction in diffuse large B-cell lymphoma, in this study we used 3-marker fluorescent multiplex immunohistochemistry and Automated Quantitative Analysis Technology to assess the CD3+, PD-L1+, and PD-1+CD3+ expression in diagnostic samples and PD-1/PD-L1 interaction as indicated by presence of PD-1+CD3+ cells in the vicinity of PD-L1+ cells, analyzed their prognostic effects in 414 patients with de novo diffuse large B-cell lymphoma, and examined whether PD-1/PD-L1 interaction is required for the prognostic role of PD-1+/PD-L1+ expression. We found that low T-cell tissue cellularity, tissue PD-L1+ expression (irrespective of cell types), PD-1+CD3+ expression, and PD-1/PD-L1 interaction showed hierarchical adverse prognostic effects in the study cohort. PD-1/PD-L1 interaction showed higher sensitivity and specificity than PD-1+ and PD-L1+ expression in predicting inferior prognosis in patients with high CD3+ tissue cellularity ("hot"/inflammatory tumors). However, both PD-1+ and PD-L1+ expression showed adverse prognostic effects independent of PD-1/PD-L1 interaction, and PD-1/PD-L1 interaction showed favorable prognostic effect in PD-L1+ patients without high CD3+ tissue cellularity. Macrophage function and tumor-cell MYC expression may contribute to the PD-1-independent adverse prognostic effect of PD-L1+ expression. In summary, low T-cell tissue cellularity has unfavorable prognostic impact in diffuse large B-cell lymphoma, and tissue PD-L1+ expression and T-cell-derived PD-1+ expression have significant adverse impact only in patients with high T-cell infiltration. PD-1/PD-L1 interaction in tissue is essential but not always responsible for the inhibitory effect of PD-L1+/PD-1+ expression. These results suggest the benefit of PD-1/PD-L1 blockade therapies only in patients with sufficient T-cell infiltration, and the potential of immunofluorescent assays and Automated Quantitative Analysis in the clinical assessment of PD-1/PD-L1 expression and interaction.


Assuntos
Linfócitos do Interstício Tumoral/patologia , Linfoma Difuso de Grandes Células B/patologia , Linfócitos T/patologia , Microambiente Tumoral/imunologia , Idoso , Antígeno B7-H1/biossíntese , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/imunologia , Feminino , Imunofluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptor de Morte Celular Programada 1/biossíntese
11.
Fish Shellfish Immunol ; 87: 847-852, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30790662

RESUMO

Growth performance, hepatic morphology and antioxidant ability, and expressions of antioxidant, inflammatory and apoptosis related genes were investigated in hybrid grouper fed high lipid diets containing 0, 0.5, 1, 2 and 10 g kg-1Lycium barbarum extract (LBE) for 8-week feeding. The study showed that dietary LBE significantly increased weight gain rate (WGR) and specific growth rate (SGR) of fish (P < 0.05), the highest WGR and SGR were observed in fish fed 10.00 g kg-1 LBE diet. Dietary LBE improved liver morphology by decreasing hepatocyte necrosis and inflammatory cell infiltration induced by high lipid diets. Meanwhile, high lipid diets supplemented with 0.5-2 g kg-1 LBE improved hepatic antioxidant ability by increasing the expression of antioxidant genes (GPx and CAT) and decreasing Keap1 mRNA levels. Moreover, dietary supplementation with 0.50-2.00 g kg -1 LBE significantly decreased IL-8, caspase-3, caspase-8 and caspase-9 mRNA levels and significantly increased IL-10 and TGF-ß1 mRNA levels in the liver of fish fed high lipid diets. In conclusion, high lipid diets supplemented with LBE improved growth performance, feed utilization and liver health in hybrid groupers by increasing hepatic antioxidant enzymes activity and its genes expression, as well as inhibition of hepatic inflammatory response and apoptosis.


Assuntos
Bass/genética , Bass/imunologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lycium/química , Extratos Vegetais/metabolismo , Ração Animal/análise , Animais , Bass/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Proteínas de Peixes/imunologia , Hibridização Genética , Fígado/imunologia
12.
Fish Shellfish Immunol ; 88: 126-134, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30779997

RESUMO

The study investigated the effects of dietary supplementation with dandelion extracts (DE) on growth performance, feed utilization, body composition, serum biochemical, liver histology, immune-related gene expression and CCl4 resistance of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀). A basal diet supplemented with DE at 0% (diet 0%), 0.1% (diet 0.1%), 0.2% (diet 0.2%), 0.4% (diet 0.4%) and 0.8% (diet 0.8%) were fed to hybrid grouper for 8 weeks. The results revealed that dietary DE had not a significant impact on growth performance and feed utilization (P > 0.05), but it could decrease the percent of crude lipids in whole body and increase the percent of crude protein in muscle (P < 0.05). Dietary DE increased the mRNA levels of antioxidant enzymes (catalase, glutathione peroxidase and glutathione reductase) and reduced inflammatory factor in the spleen and head-kidney of fish (P < 0.05), but reduced the expression of the liver antioxidant gene except for glutathione reductase (P < 0.05). Dietary supplementation with 0.2%-0.4% DE could effectively improve liver health. After injection of CCL4 by 72 h, fish fed Diet0.2% and Diet0.4% showed regular hepatocyte morphology while fish fed Diet 0%, Diet 0.1% and Diet 0.8% showed hepatocyte damage. Higher survival rate and total blood cell count was observed in fish fed 0.1%-0.4% dietary DE (P < 0.05). In conclusion, DE could be used as a functional feed additive to enhance liver function of farmed fish. The best level of it should be between 0.2% and 0.4%.


Assuntos
Ração Animal/análise , Bass/crescimento & desenvolvimento , Tetracloreto de Carbono/toxicidade , Extratos Vegetais/farmacologia , Taraxacum , Animais , Bass/genética , Bass/imunologia , Bass/fisiologia , Composição Corporal , Dieta/veterinária , Regulação da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Lipídeos/análise , Fígado/efeitos dos fármacos , Fígado/patologia , Músculos/química
13.
Bioconjug Chem ; 29(10): 3285-3292, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30234289

RESUMO

Glyoxylate-mediated transamination (GT) is a classic, potentially general, and N-terminus-specific protein modification method useful for the preparation of bioconjugates. However, there is a lack of information on whether and how readily a particular N-terminal amino acid (in the context of a peptide chain) can be converted to the 2-oxoacyl moiety under GT conditions. Here, we conducted a systematic investigation of GT using membrane-bound dipeptide arrays that include all the 400 possible dipeptide combinations of the 20 genetically encoded amino acids. This colorimetric method offers a convenient way to assess the GT reaction tendency of N-terminal residues by the naked eye. It also provides interesting information about the effect of the second residues on GT, which has not been reported previously. In addition, we also designed a proteomics approach to study GT in solution using tryptic peptide mixtures, which not only confirmed many of our findings in peptide array assays but also revealed potential side reaction products. Taken together, our studies will make the future use of GT for protein modification in a much more predictable way.


Assuntos
Glioxilatos/química , Peptídeos/química , Proteômica , Aminação , Biomimética , Colorimetria/métodos , Misturas Complexas , Dipeptídeos/química , Mapeamento de Peptídeos , Tripsina/química
14.
Bioconjug Chem ; 29(9): 2892-2898, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30130094

RESUMO

Based on the exceptionally high stability of γPNA duplexes, we designed a peptide/γPNA chimera in which a cell-penetrating TAT peptide is flanked by two short complementary γPNA segments. Intramolecular hybridization of the γPNA segments results in a stable hairpin conformation in which the TAT peptide is constrained to form the loop. The TAT/γPNA hairpin (self-cyclized TAT peptide) enters cells at least 10-fold more efficiently than its nonhairpin analog in which the two γPNA segments are noncomplementary. Extending one of the γPNA segments in the hairpin results in an overhang that can be used for binding and delivering a variety of nucleic acid-conjugated molecules into cells via hybridization to the overhang. We demonstrated efficient cellular delivery of a protein (as low as 10 nM) and a DNA tetrahedron by a TAT/γPNA hairpin.


Assuntos
DNA/química , Conformação de Ácido Nucleico , Ácidos Nucleicos Peptídicos/química , Peptídeos/química , Células A549 , Humanos , Microscopia de Fluorescência , Hibridização de Ácido Nucleico
15.
Fish Shellfish Immunol ; 73: 234-244, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29127028

RESUMO

Growth, plasma biochemical parameters, fish composition, immune parameters, intestinal histology, and expressions of immune-related genes were examined in hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀) that fed respectively six diets containing Panax notoginseng extract (PNE) at 0, 0.5, 1, 2, 4, and 10 g kg-1 after 8 weeks. Results indicated that dietary PNE significantly improved growth, feed efficiency ratio, protein efficiency ratio, and protein deposit rate, and significantly increased crude protein and crude lipid levels of whole body and crude protein level of muscle. Dietary PNE significantly increased plasma total protein, alkaline phosphatase, immunoglobulin, complement 3 and complement 4 contents, but significantly decreased cholesterol, triglyceride, glucose, and low density lipoprotein cholesterol contents. Furthermore, dietary PNE increased villus length and muscle thickness in foregut, midgut, and hindgut, activities of hepatic superoxide dismutase and total antioxidant capacity, and increased the expression levels of immune related genes (IL-10, TGF-ß1, TOR, MHC2 and TLR3) in the head kidney and the expression levels of antioxidant genes (CAT and GR) in fish that fed PNE at 0.5-4 g kg-1. In conclusion, grouper fed high lipid diets supplemented with PNE at 0.5-10 g kg-1 improved growth, feed utilization, blood immune parameters, hepatic antioxidant status, intestine morphology and expression levels of immune related genes in the head kidney.


Assuntos
Bass/fisiologia , Medicamentos de Ervas Chinesas/metabolismo , Expressão Gênica/imunologia , Imunidade Inata/genética , Intestinos/efeitos dos fármacos , Metabolismo dos Lipídeos , Ração Animal/análise , Animais , Bass/anatomia & histologia , Bass/genética , Bass/imunologia , Dieta/veterinária , Suplementos Nutricionais/análise , Medicamentos de Ervas Chinesas/administração & dosagem , Hibridização Genética , Intestinos/anatomia & histologia , Distribuição Aleatória
16.
Fish Shellfish Immunol ; 83: 8-17, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30145200

RESUMO

The present study is aiming at evaluating the hepatoprotective of Radix Bupleuri extracts (RBE) on the d-galactosamine/lipopolysaccharide (D-GalN/LPS) induced liver injury of hybrid grouper in vitro and in vivo. In vitro, RBE (0, 200, 400 and 800 µg/ml) was added to the hybrid grouper primary hepatocytes before (pretreatment) the incubation of the hepatocytes with D-GalN (20 mM) plus LPS (1 µg/ml) in the culture medium. RBE at concentrations of 200, 400 and 800 µg/ml significantly improved cell viability and inhibited the elevation of TNF-α, IL-1ß and IL-6 and significantly down-regulated the caspase-3, caspase-9 and P53 mRNA levels. In vivo administration of RBE at the doses of 0, 200, 400, 800 and 1600 mg/kg in the diet for 8 weeks prior to D-GalN (500 mg/kg) and LPS (20 µg/kg) intoxication. The study indicated that the RBE not only ameliorated liver injury, as evidenced by well-preserved liver architecture, but also significantly increased hepatic antioxidant enzymes activities in the D-GalN/LPS-induced liver injury animal model. Further demonstrating the protective effects of the RBE, we found that pretreatment with the RBE up-regulated the expression of antioxidant genes (GPx and MnSOD), while down-regulated apoptosis-related genes (caspase-3, caspase-9 and P53), immune related genes (MHC2 and TLR3) and pro-inflammatory cytokines (TOR and IKKα) mRNA expression in the liver of hybrid grouper. In brief, the present study showed that RBE can protect hepatocyte injury induced by D-GalN/LPS through elevating antioxidant enzyme activity and suppressing apoptosis and immune inflammatory responses. The results support the use of RBE as a hepatoprotective in fish.


Assuntos
Bass , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Ranunculaceae/química , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimera , Feminino , Galactosamina , Regulação da Expressão Gênica , Hepatócitos/patologia , Lipopolissacarídeos , Fígado/patologia , Masculino , Raízes de Plantas/química
17.
Fish Shellfish Immunol ; 73: 197-206, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29258755

RESUMO

Intestinal morphology, antioxidant status, immune function and tight junction proteins mRNA expression were examined in golden pompano (Trachinotus ovatus) that fed respectively six diets containing dandelion extracts (DE) at 0, 0.5, 1, 2, 4 and 10 g kg-1 after 8 weeks feeding. The study indicated that dietary DE significantly improved intestinal antioxidant abilities by increasing SOD, CAT, T-AOC activities and up-regulating intestinal cat, gpx mRNA levels, but by decreasing MDA content and down-regulating intestinal keap1 mRNA levels in golden pompano. Meanwhile, dietary DE improved intestinal morphology, suggesting that enhances intestinal digestion and absorption, by increasing muscle thickness, villus length, villus width and villus number in the foregut and hindgut; as well as villus number, villus width and muscle thickness in the midgut (P < .05). Dietary DE enhanced intestinal barrier function by increasing intestinal zo-1 and occludin mRNA levels, but by decreasing the mRNA levels of claudin-12 and claudin-15. Furthermore, dietary DE improved intestinal immunity via increasing goblet cells numbers and regulating expression of immune-related genes. In conclusion, dietary DE supplementation promoted intestine health by improving intestine morphology, immunity, antioxidant abilities and intestinal barrier in golden pompano.


Assuntos
Antioxidantes/metabolismo , Imunidade Inata/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Perciformes/fisiologia , Extratos Vegetais/metabolismo , Taraxacum/química , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Imunidade Inata/imunologia , Mucosa Intestinal/metabolismo , Intestinos/anatomia & histologia , Perciformes/genética , Perciformes/imunologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Distribuição Aleatória , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo
18.
Fish Shellfish Immunol ; 72: 399-409, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29032040

RESUMO

For thousands of years, leaves from the Ginkgo biloba tree have been a common treatment in Chinese medicine. The present study was conducted to investigate the effects of dietary ginkgo biloba leaf extract (GBE) supplementation on growth performance, plasma biochemical parameters, fish composition, immune responses, liver histology, and immune and apoptosis-related genes expression of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀) fed high lipid diets. A basal diet supplemented with GBE at 0, 0.50, 1.00, 2.00, 4.00 and 10.00 g kg-1 was fed to hybrid grouper for 8 weeks. The study indicated that dietary GBE did not improve growth performance and feed utilization but it reduced intraperitoneal fat rate. There were no significant differences in condition factor, viscerosomatic index, hepatosomatic index, spleen index, relative gut length, food intake, protein deposit rate and survival among all groups (P > 0.05). Dietary supplementation with 0.50-4.00 g GBE kg-1 diets effectively increased plasma HDL content and decreased plasma GLU, LDL and TG content in fish. Furthermore, dietary GBE had a significant effect on moisture, crude protein and lipid in the liver, and protein in the whole body of fish (P < 0.05). Dietary supplementation with 0.50-1.00 g GBE kg-1 diets effectively decreased occurrence rates of the hepatocyte swelling, hepatocyte vacuolization, and nuclei shifting to the cellular periphery cytoplasmic vacuolization, meanwhile hepatic antioxidant enzymes (SOD, CAT and T-AOC) activities significantly increased whereas MDA content significantly decreased in fish fed diets supplemented with GBE (P < 0.05). Moreover, dietary GBE up-regulated the expression of antioxidant genes (CAT, GPx and GR), immune-related genes (MHC2 and TLR3) and anti-inflammatory cytokines (IL-10 and TGF-ß1), while dietary supplementation with 0.50-4.00 g GBE kg-1 diets down-regulated apoptosis-related genes (p53, caspase-9, caspase-8 and caspase-3) expression in the head kidney of hybrid grouper. These results indicated that hybrid grouper fed diets supplemented with GBE did not improve growth performance and feed utilization but it had hypolipidemic effects, improved hepatic antioxidant status, maintained normal liver histology and preserved liver function, increased immune-related genes expression and decreased apoptosis-related genes expression in the head kidney of hybrid grouper.


Assuntos
Apoptose/efeitos dos fármacos , Bass/fisiologia , Expressão Gênica/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Extratos Vegetais/metabolismo , Ração Animal/análise , Animais , Bass/genética , Bass/crescimento & desenvolvimento , Bass/imunologia , Dieta/veterinária , Suplementos Nutricionais/análise , Proteínas de Peixes/genética , Ginkgo biloba , Extratos Vegetais/administração & dosagem , Distribuição Aleatória
19.
Appl Opt ; 57(20): 5657-5665, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30118078

RESUMO

The deployment of polishing slurry is one of the important research topics in the field of chemical-mechanical polishing. It is expected that technological breakthroughs in this process will lead to an improvement of the surface quality of fabricated optical components. In this investigation, we added several types of electrolytes into cerium oxide polishing slurries and evaluated their influence on the material removal rate (MRR) and surface roughness (Sa) during K9 glass polishing. Furthermore, we investigated their influence on the zeta potential, particle size distribution, and suspension stability of the slurries. The results show that the introduction of an electrolyte into the polishing slurry changes not only the zeta potential of the ceria particle surface, but also the type and thickness of the deposited solvent film. The presence of a hydrophilic solvent film results in repulsion between individual particles and between the particles and the glass surface. However, a hydrophobic solvent film enhances the attraction between individual particles and between the particles and the glass surface. Moreover, thicker solvation films correspond to a greater force. This has a great impact on the interfacial interaction between the particles and the glass surface during the polishing process. The presence of the hydrophobic solvent film results in a high MRR, while the hydrophilic solvent film is associated with low Sa. In this paper, the interaction mechanisms of the abrasive particles and the glass interface during the polishing process are elucidated by considering the zeta potential and the solvent film type. In addition, a method for reducing the resulting Sa after glass polishing is proposed.

20.
J Am Chem Soc ; 139(26): 9001-9009, 2017 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-28644615

RESUMO

An RNA aptamer selected for binding to the fluorogenic cyanine dye, dimethylindole red (DIR), also binds and activates another cyanine, oxazole thiazole blue (OTB), giving two well-resolved emission colors. The aptamer binds to each dye with submicromolar KD values, and the resulting fluoromodules exhibit fluorescence quantum yields ranging from 0.17 to 0.51 and excellent photostability. The aptamer was fused to a second aptamer previously selected for binding to the epidermal growth factor receptor (EGFR) to create a bifunctional aptamer that labels cell-surface EGFR on mammalian cells. The fluorescent color of the aptamer-labeled EGFR can be switched between blue and red in situ simply by exchanging the dye in the medium. The promiscuity of the aptamer can also be used to distinguish between cell-surface and internalized EGFR on the basis of the addition of red or blue fluorogen at different times.


Assuntos
Aptâmeros de Nucleotídeos/química , Carbocianinas/química , Corantes Fluorescentes/química , RNA/química , Receptores ErbB/química , Microscopia Confocal , Estrutura Molecular , Imagens de Fantasmas
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