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1.
Small ; 20(38): e2401308, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38773889

RESUMO

Incorporating ultralow loading of nanoparticles into polymers has realized increases in dielectric constant and breakdown strength for excellent energy storage. However, there are still a series of tough issues to be dealt with, such as organic solvent uses, which face enormous challenges in scalable preparation. Here, a new strategy of dual in situ synthesis is proposed, namely polymerization of polyethylene terephthalate (PET) synchronizes with growth of calcium borate nanoparticles, making polyester nanocomposites from monomers directly. Importantly, this route is free of organic solvents and surface modification of nanoparticles, which is readily accessible to scalable synthesis of polyester nanocomposites. Meanwhile, uniform dispersion of as ultralow as 0.1 wt% nanoparticles and intense bonding at interfaces have been observed. Furthermore, the PET-based nanocomposite displays obvious increases in both dielectric constant and breakdown strength as compared to the neat PET. Its maximum discharged energy density reaches 15 J cm-3 at 690 MV m-1 and power density attains 218 MW cm-3 under 150 Ω resistance at 300 MV m-1, which is far superior to the current dielectric polymers that can be produced at large scales. This work presents a scalable, safe, low-cost, and environment-friendly route toward polymer nanocomposites with superior capacitive performance.

2.
Phys Chem Chem Phys ; 26(31): 21009-21018, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39051262

RESUMO

Anion photoelectron spectroscopy and theoretical calculations were used to investigate the structural and bonding properties of WN10-/0. The electron affinity of WN10 is measured to be 1.582 ± 0.030 eV. The frequency of the NN stretch in WN10 is measured to be 2170 ± 80 cm-1, which is red-shifted with respect to that of the dinitrogen molecule indicating that the NN bonds are weakened in WN10. The theoretical adiabatic detachment energy (ADE) and vertical detachment energy (VDE) of WN10- obtained by calculations at the CCSD(T)/CBS level agree well with experimental results. The structures of WN10-/0 are C4v symmetric pentacoordinated pyramidal structures with five end-on dinitrogen ligands. Our experiments show that the peak of WN10- is dominant in the mass spectrum of anionic WNn, whereas the mass peak of WN12+ is dominant in the mass spectrum of cationic WNn, implying that the stabilities of WNn clusters are strongly related to their charge states.

3.
Phys Chem Chem Phys ; 26(34): 22491-22497, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39145725

RESUMO

Enhanced dielectric constant and high breakdown strength offers immense promise for excellent energy storage performance, which is of critical significance in modern electronics and power systems. However, polymer nanocomposites with traditional routes have to balance between dielectric constant and breakdown strength, hence hindering substantive increases in energy density. Herein, a sandwiched polymer nanocomposite film has been constructed to take full advantage of the individual component layers. BaTiO3 nanoparticles are coated with a fluoropolymer to form core-shell structures and then introduced into a polymer as the top and the bottom layers of a sandwich film for enhancing polarization. Moreover, boron nitride nanosheets (BNNSs) in the middle layer of the sandwich film exert positive effects on the inhibition of current leakage for high breakdown resistance. The breakdown strength increases from 480 MV m-1 of the neat polymer to 580 MV m-1 of the sandwiched film. Additionally, the film exhibits a higher dielectric constant in comparison with the neat polymer. The sandwiched film displays a superior energy density (15.75 J cm-3), which is about 1.9 times that of the neat polymer. This work proposes a feasible route to achieve excellent energy storage of polymer dielectrics by synergistically introducing insulating fillers and additional dipoles in a sandwiched polymer nanocomposite film.

4.
Small ; 19(35): e2300804, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37183292

RESUMO

The rational design of the directional charge transfer channel represents an important strategy to finely tune the charge migration and separation in photocatalytic CO2 -to-fuel conversion. Despite the progress made in crafting high-performance photocatalysts, developing elegant photosystems with precisely modulated interfacial charge transfer feature remains a grand challenge. Here, a facile one-pot method is developed to achieve in situ self-assembly of Pd nanocrystals (NYs) on the transition metal chalcogenide (TMC) substrate with the aid of a non-conjugated insulating polymer, i.e., branched polyethylenimine (bPEI), for photoreduction of CO2 to syngas (CO/H2 ). The generic reducing capability of the abundant amine groups grafted on the molecular backbone of bPEI fosters the homogeneous growth of Pd NYs on the TMC framework. Intriguingly, the self-assembled TMCs@bPEI@Pd heterostructure with bi-directional spatial charge transport pathways exhibit significantly boosted photoactivity toward CO2 -to-syngas conversion under visible light irradiation, wherein bPEI serves as an efficient hole transfer mediator, and simultaneously Pd NYs act as an electron-withdrawing modulator for accelerating spatially vectorial charge separation. Furthermore, in-depth understanding of the in situ formed intermediates during the CO2 photoreduction process are exquisitely probed. This work provides a quintessential paradigm for in situ construction of multi-component heterojunction photosystem for solar-to-fuel energy conversion.

5.
Inorg Chem ; 62(1): 520-529, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36563080

RESUMO

Metal nanoclusters (NCs) have been unleashed as an emerging category of metal materials by virtue of integrated merits including the unusual atom-stacking mode, quantum confinement effect, and fruitful catalytically active sites. Nonetheless, development of metal NCs as photosensitizers is blocked by light-induced instability and ultrashort carrier lifespan, which remarkably retards the design of metal NC-involved photosystems, hence resulting in the decreased photoactivities. To solve these obstacles, herein, we conceptually probed the charge transfer characteristics of the BiVO4 photoanode photosensitized by atomically precise alloy metal NCs, wherein tailor-made l-glutathione-capped gold-silver bimetallic (AuAg) NCs were controllably self-assembled on the BiVO4 substrate. It was uncovered that alien Ag atom doping is able to effectively stabilize the alloy AuAg NCs and simultaneously photosensitize the BiVO4 photoanode, significantly boosting the photoelectrochemical (PEC) water oxidation performances. The reasons for the robust and stable PEC water oxidation activities of the AuAg NCs/BiVO4 composite photoanode were unambiguously unleashed. We ascertain that Ag atom doping in the staple motif of Aux NCs efficaciously protects the NCs from rapid oxidation, enhancing the photostability, boosting the photosensitization efficiency, and thus leading to the considerably improved PEC water splitting activities compared with the homometallic counterpart. This work could afford a new strategy to judiciously tackle the inherent detrimental instability of metal NCs for solar energy conversion.

6.
Phys Chem Chem Phys ; 25(27): 18030-18037, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37378512

RESUMO

Improved dielectric constant and breakdown strength facilitates excellent energy storage density of polymer dielectrics, which is positive to miniaturize dielectric capacitors in electronic and electrical systems. Although coating polar substances on nanoparticles enhances the dielectric constants of polymer nanocomposites, it usually causes local electric field concentration, leading to poor breakdown strength. Here, fluoropolymers with tailorable fluorine content (PF0, PF30 and PF60) are coated on BaTiO3 (BT) nanoparticles to construct typical core-shell structures that are further blended with poly(vinylidenefluoride-co-hexafluoropropylene) (P(VDF-HFP)) to obtain BT@PF/P(VDF-HFP) nanocomposites. Uniform dispersion of nanoparticles and excellent compatibility of interfaces are observed for the samples. In addition, the dielectric constant gradually increases from 8.03 to 8.26 to 9.12 for the nanocomposites filled with 3 wt% BT@PF0, BT@PF30 and BT@PF60, respectively. However, 3 wt% BT@PF30/P(VDF-HFP) has the highest breakdown strength (455 kV mm-1) among the nanocomposites, which is as good as neat P(VDF-HFP). More importantly, BT@PF30 rather than BT@PF60 possesses the maximum discharged energy density (11.56 J cm-3 at 485 kV mm-1), which is about 1.65 times that of neat P(VDF-HFP). This work proposes a facile experimental route to optimize the dielectric constants of the shell layer to couple the dielectric constants between the nanoparticles, shell layer and polymer matrix, which contributes to alleviating the local electric field concentration for excellent breakdown strength and electrical energy storage of polymer nanocomposites.

7.
Inorg Chem ; 61(44): 17828-17837, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36274200

RESUMO

Transition-metal chalcogenides (TMCs) have received enormous attention by virtue of their large light absorption coefficient, abundant catalytically active sites, and markedly reduced spatially vectorial charge-transfer distance originating from generic structural merits. However, the controllable construction of TMC-based heterostructured photosystems for photocatalytic carbon dioxide (CO2) reduction is retarded by the ultrashort charge lifetime, sluggish charge-transfer kinetics, and low target product selectivity. Herein, we present the rational design of two-dimensional (2D)/zero-dimensional (0D) heterostructured CO2 reduction photosystems by an electrostatic self-assembly strategy, which is enabled by precisely anchoring CsPbBr3 quantum dots (QDs) on the 2D TMC (CdIn2S4, ZnIn2S4, In2S3) frameworks. The peculiar 2D/0D integration mode and suitable energy-level alignment between these two assembly units afford maximal interfacial contact and applicable potential for CO2 photoreduction, thus endowing the self-assembled TMCs/CsPbBr3 nanocomposites with considerably improved visible-light-driven photocatalytic performances toward CO2 reduction to carbon monoxide with high selectivity. The enhanced photocatalytic performances of TMCs/CsPbBr3 heterostructures are attributed to the abundant active sites on the TMC frameworks, excellent light absorption of CsPbBr3 QDs, and well-defined 2D/0D heterostructures of TMCs/CsPbBr3 QDs photosystems, which synergistically boosts the directional charge transport from CsPbBr3 QDs to TMCs, enhancing the interfacial charge migration/separation. Our work would inspire the construction of novel TMCs-involved photosystems for solar-to-fuel conversion.

8.
Inorg Chem ; 61(47): 19022-19030, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36377248

RESUMO

Atomically precise metal nanoclusters (NCs) have recently emerged as a promising sector of metal nanomaterials in terms of peculiar atomic stacking fashion, quantum confinement effect, and enriched catalytically active sites, which are wholly distinct from conventional metal nanocrystals (NYs) in all respects. However, atomically precise metal NCs inevitably suffer from intrinsic poor instability either under light irradiation or thermal treatment owing to the ultrahigh surface energy, thereby resulting in substantial loss of photosensitization efficiency and retarding their emerging utilization in photoredox catalysis. Here, we first conceptually reveal the charge transfer characteristic difference between atomically precise metal NCs and metal NYs attained by self-transformation in boosting interfacial charge migration and separation. The results signify that the interfacial charge transfer impetus of atomically precise metal NCs as a photosensitizer versus metal NYs as a Schottky-type electron-withdrawing mediator is closely associated with the loading amount on the semiconductor substrate. The photosensitization effect of atomically precise metal NCs is superior to the electron trapping capability of metal NYs when the loading amount of the metal ingredient is relatively high and vice versa. Our work would significantly bridge the gap between atomically precise metal NCs and metal NYs in fine tuning of the charge transfer pathway in photocatalysis toward solar energy conversion.

9.
J Perianesth Nurs ; 36(6): 638-641, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34580019

RESUMO

PURPOSE: To describe the retrospective audit examining nursing care of nonvalvular atrial fibrillation treated by percutaneous left atrial appendage closure (PLAAC). DESIGN: PLAAC is a new technique for patients with atrial fibrillation unsuited for long-term oral anticoagulation treatment. The nursing care for patients treated by PLAAC has not yet been standardized. METHODS: We performed a retrospective analysis of 259 patients with nonvalvular atrial fibrillation who underwent PLAAC in our department between August 2014 and June 2018. The data included preoperative evaluations, discussions, and preparations, including psychological care and atrial thrombosis screening; postoperative observations, including electrocardiograph monitoring; prevention and care of complications; administration of postoperative anticoagulation therapy; and postoperative education, including detailed discharge guidance and regular follow-up. FINDINGS: All patients were discharged after 5-10 days of hospitalization. In the perioperative period, 4 cases (1.5%) developed serious complications, including 3 cases (1.2%) of delayed cardiac tamponade, cured by pericardial drainage, and 1 case of a suspected air embolism, which spontaneously recovered. During a mean follow-up period of 25.9 ± 7.9 months, all patients had good adherence to medical instructions and there were no cases of occluder displacement or shedding, thromboembolism, or severe bleeding complications. CONCLUSIONS: The best therapeutic effect of PLAAC is strongly associated with the preoperative and postoperative training of nursing staff and the development of standard nursing procedures, including the establishment of observation and nursing manuals for complications. This study provides nursing practice information to aid in the standardization of nursing procedures for this new type of interventional therapy.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Acidente Vascular Cerebral , Anticoagulantes/uso terapêutico , Apêndice Atrial/cirurgia , Humanos , Enfermagem Perioperatória , Estudos Retrospectivos , Resultado do Tratamento
10.
Fish Shellfish Immunol ; 104: 527-536, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32599058

RESUMO

Complement component 4 (C4) has critical immunological functions in vertebrates. In the current study, a C4 homolog (gcC4) was identified in grass carp (Ctenopharyngodon idella). The full-length 5458 bp gcC4 cDNA contained a 5148 bp open reading frame (ORF) encoding a protein of 1715 amino acids with a signal peptide and eight conservative domains. The gcC4 protein has a high level of identity with other fish C4 counterparts and is phylogenetically clustered with cyprinid fish C4. The gcC4 transcript shows wide tissue distribution and is inducible by Aeromonas hydrophila in vivo and in vitro. Furthermore, its expression also fluctuates upon lipopolysaccharide or flagellin stimulation in vitro. During infection, the gcC4 protein level decreases or increases to varying degrees, and the intrahepatic C4 expression location changes. With gcC4 overexpression, interleukin 1 beta, tumor necrosis factor alpha, and interferon transcripts are all upregulated by A. hydrophila infection. Meanwhile, overexpression of gcC4 reduces bacterial invasion or proliferation. Moreover, gcC4 may activate the NF-κB signaling pathway. These findings demonstrate the vital role of gcC4 in the innate immunity of grass carp.


Assuntos
Carpas/genética , Carpas/imunologia , Complemento C4/genética , Complemento C4/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Animais , Complemento C4/química , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , NF-kappa B/fisiologia , Filogenia , Alinhamento de Sequência/veterinária , Transdução de Sinais/imunologia
11.
Fish Shellfish Immunol ; 89: 437-447, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980916

RESUMO

Proteinase inhibitors with the ability to inhibit specific proteinases are usually closely connected with the immune system. Interestingly, proteinase inhibitors are also a common ingredient in the organic matrix of mollusk shells. However, the molecular mechanism that underlies the role of proteinase inhibitors in immune system and shell mineralization is poorly known. In this study, a Kunitz serine proteinase inhibitor (HcKuPI) was isolated from the mussel Hyriopsis cumingii. HcKuPI was specifically expressed in dorsal epithelial cells of the mantle pallium and HcKuPI dsRNA injection caused an irregular surface and disordered deposition on the aragonite tablets of the nacreous layer. These results indicated that HcKuPI plays a vital role in shell nacreous layer biomineralization. Moreover, the expression pattern of HcKuPI during LPS challenge and pearl formation indicated its involvement in the antimicrobial process during pearl sac formation and nacre tablets accumulation during pearl formation. In the in vitro calcium carbonate crystallization assay, the addition of GST-HcKuPI increased the precipitation rate of calcium carbonate and induced the crystal overgrowth of calcium carbonate. Taken together, these results indicate that HcKuPI is involved in antimicrobial process during pearl formation, and participates in calcium carbonate deposition acceleration and morphological regulation of the crystals during nacreous layer formation. These findings extend our knowledge of the role of proteinase inhibitors in immune system and shell biomineralization.


Assuntos
Antibacterianos/metabolismo , Carbonato de Cálcio/metabolismo , Nácar/metabolismo , Inibidores de Proteases , Unionidae/genética , Unionidae/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Unionidae/metabolismo
12.
Biotechnol Appl Biochem ; 66(1): 14-20, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30194872

RESUMO

Matrix proteins play important roles in molluscan shell biomineralization, which helps in the understanding of mechanisms associated with pearl formation. In this study, we characterized the gene encoding a novel shell-matrix protein, hic24, in Hyriopsis cumingii and investigated its structure and function. The full cDNA sequence of hic24 is 756 bp, with an open reading frame of 654 bp encoding 217 amino acids, including a signal peptide of 18 amino acids. Sequence analysis revealed that the protein is ∼23.5 kDa, and that Gly accounted for 11.5% of the total amino acid content. Secondary structure prediction indicated a structure comprised predominantly by ß-folds. Quantitative real-time polymerase chain reaction and in situ hybridization indicated that hic24 is expressed in the dorsal epithelial cells of the mantle, indicating hic24 as a nacreous-layer matrix protein. Additionally, hic24 expression patterns during pearl biomineralization showed that hic24 regulates the growth of the later nacreous layer. After attenuating hic24 expression by RNA interference in the mantle, we observed that hic24 plays a role in biomineralization of the shell nacre by inhibiting calcium carbonate nucleation.


Assuntos
Calcificação Fisiológica/fisiologia , Proteínas da Matriz Extracelular , Regulação da Expressão Gênica/fisiologia , Nácar , Unionidae , Sequência de Aminoácidos , Animais , DNA Complementar , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Nácar/genética , Nácar/metabolismo , Fases de Leitura Aberta , Domínios Proteicos , Unionidae/genética , Unionidae/metabolismo
13.
Biotechnol Appl Biochem ; 66(4): 545-554, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30990920

RESUMO

Biological mineralization is a highly programmed process in which inorganic minerals reassociate under the strict control of the extracellular matrix to form minerals with special functions and patterns. Shells are biominerals, and their synthesis is finely regulated by organic matrix including matrix proteins, polysaccharides, lipids, pigments, free amino acids, and small peptides. In this study, two matrix protein genes, hic14 and hic19, were isolated from the mantle of the mussel Hyriopsis cumingii. Tissue expression analysis showed that both proteins were expressed mainly in the mantle, and in situ hybridization of mantle tissues showed that they were specifically expressed in the dorsal epithelial cells of mantle pallial. Therefore, hic14 and hic19 were both nacreous layer matrix proteins. In the pearl insertion experiment, hic14 and hic19 kept low expression during pearl sac formation and disordered calcium carbonate deposition, and increased significantly during pearl nacre accumulation, which showed that both proteins participated in the mineralization of pearl nacre. In the RNA interference experiment, shell nacre tablet growth was inhibited after crystal nucleation due to the decreased expression of hic14, and crystal morphology and arrangement of nacre were highly modified after expression of hic19 was inhibited. These results provided further evidence that both hic14 and hic19 participated in nacreous layer biomineralization.


Assuntos
Bivalves/genética , Bivalves/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Animais , Bivalves/química , Clonagem Molecular , Cristalização , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
14.
Eur Radiol ; 27(4): 1527-1536, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27525973

RESUMO

PURPOSE: To study the thyroid image reporting and data system (TI-RADS) classification and the contrast-enhanced ultrasound (CEUS) enhancement pattern of thyroid nodules, and to determine whether combined use of both methods is helpful in the diagnosis of thyroid nodules. METHODS: A total of 319 thyroid nodules in 246 patients were assessed with TI-RADS, CEUS and a combination of both methods. The diagnostic performance of TI-RADS, CEUS and a combination of both methods was compared. RESULTS: The accuracy in the diagnosis of thyroid nodules was 90.3 % for TI-RADS, 90.0 % for CEUS and 96.0 % for a combination of both methods respectively. A statistically significant difference was not observed in the diagnostic accuracy of CEUS and TI-RADS (P > 0.05). However, a significant difference was observed between a combination of both methods and either alone (P < 0.01). A combination of both methods showed high sensitivity, specificity and accuracy for TI-RADS classifications of 4a and 4b thyroid nodules compared with TI-RADS alone (P < 0.01) and a statistically significant difference was not observed for thyroid nodules classified as 2, 3, and 5 (P > 0.05). CONCLUSIONS: The improved TI-RADS, when combined with CEUS, could significantly improve the diagnostic accuracy for thyroid nodules, especially for TI-RADS class-4 thyroid nodules. KEY POINTS: • TI-RADS can be used as the primary diagnostic standard for thyroid nodules • CEUS can be used as an important complement to TI-RADS • The improved TI-RADS can significantly improve the qualitative diagnostic accuracy.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Sistemas de Informação em Radiologia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Adulto Jovem
15.
Fish Shellfish Immunol ; 70: 121-128, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28866274

RESUMO

Aeromonas hydrophila is the causative agent of bacterial septicemia that is frequently observed in grass carp, Ctenopharyngodon idellus. In this study, we evaluated the biological parameters and immune enzymes in the liver of grass carp following A. hydrophila infection and quantified the alterations in liver histology using a semi-quantitative system. For the biological parameters, we found that the liver somatic index (LSI) was more sensitive than Fulton's condition factor (CF) and was significantly decreased at three days post-injection (DPI). At the immune enzyme level, the level of peroxidase (POD) in the liver significantly increased at 1 and 3 DPI. The activity of alkaline phosphatase (ALP) significantly increased at 3 DPI. Similarly, acid phosphatase (ACP) activity significantly increased at 1, 3, and 5 DPI. Histologically, the results indicated that the liver index at 3, 5, and 7 DPI was significantly higher than that of control groups. The regressive alterations as the highly variable reactions patterns and its index at 5 DPI was significantly higher than that of 1, 21 DPI, and the control groups. Based on our results, we suggest that grass carp resist A. hydrophila infection via an innate immune mechanism in the liver. The findings of this study will help elucidate the underlying mechanisms of resistance to A. hydrophila infection.


Assuntos
Carpas , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Imunidade Inata , Fígado/imunologia , Aeromonas hydrophila/fisiologia , Animais , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Fígado/anatomia & histologia
16.
Fish Shellfish Immunol ; 66: 93-102, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28479400

RESUMO

The mannan-binding lectin-associated serine protease-1 (MASP-1) gene is a crucial component of the lectin pathway in the complement and coagulation cascade. Although MASP-1 has been found in the immune system of teleosts, its immune functions in response to bacterial infection are unclear. In this study, we identified a MASP-1 homolog (gcMASP-1) in the grass carp (Ctenopharyngodon idella). The full-length 3308-bp gcMASP-1 cDNA includes a 2160-bp open reading frame encoding a protein composed of 719 amino acids with epidermal growth factor-like, complement control protein, and trypsin-like domains. gcMASP-1 shares a high similarity with MASP-1 counterparts in other species, and it is most closely related to Cyprinus carpio MASP-1 and Sinocyclocheilus anshuiensis MASP-1. Transcription of gcMASP-1 was widely distributed in different tissues and induced by Aeromonas hydrophila in vivo and in vitro. Expression of gcMASP-1 was also affected by lipopolysaccharide and flagellin stimulation in vitro. In cells over-expressing gcMASP-1, transcript levels of almost all components, except gcMBL and gcC5, were significantly enhanced, and gcIL1ß, gcTNF-α, gcIFN, gcCD59, gcC5aR1, and gcITGß-2 were significantly upregulated after exposure to A. hydrophila; gcMASP-1 interference downregulated the transcript levels after A. hydrophila challenge. In addition, gcMASP-1 activated NF-κB signaling. These findings indicate the vital role of gcMASP-1 in innate immunity in C. idella.


Assuntos
Aeromonas hydrophila/imunologia , Carpas , Doenças dos Peixes/enzimologia , Proteínas de Peixes/metabolismo , Infecções por Bactérias Gram-Negativas/veterinária , Imunidade Inata/genética , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Aeromonas hydrophila/fisiologia , Animais , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Infecções por Bactérias Gram-Negativas/enzimologia , Infecções por Bactérias Gram-Negativas/imunologia , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Análise de Sequência de DNA/veterinária
17.
Gen Comp Endocrinol ; 229: 112-8, 2016 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-26979275

RESUMO

Insulin-like androgenic gland hormone gene (IAG) is a sex regulator specifically expressed in male crustaceans, controlling the male sexual differentiation, spermatogenesis and reproductive strategy. Our previous study reported the cloning and characterization of the prawn Macrobrachium nipponense IAG (MnIAG). In this study, we further identified a 2214-bp MnIAG 5'-flanking region, and analyzed its transcription factor binding sites and transcriptional activity. The results showed that there were two potential promoter core sequences, three TATA boxes and one CAAT box existing in the MnIAG 5'-flanking region as well as many potential transcription factor binding sites, such as SRY, Sox-5, GATA-1, etc. Notably, the transcriptional activity was weak in this region, and a negative regulatory region was found in -604 to -231bp. In addition, we constructed M. nipponense yeast libraries and identified proteins interacting with the MnIAG protein by yeast two hybridization assay. The yeast two-hybrid screening yielded ten positive clones, of which five were annotated by NCBI database, namely heat shock protein 21, NADH dehydrogenase, zinc finger protein, beta-N-acetylglucosaminidase and a hypothetical protein. The identification of MnIAG putative regulatory region and proteins that interact with IAG will facilitate our understanding of the regulatory role of MnIAG and provide a foundation for deep insight into the prawn sex differentiation mechanism and signaling transduction pathways.


Assuntos
Insulinas/genética , Palaemonidae/metabolismo , Técnicas do Sistema de Duplo-Híbrido/estatística & dados numéricos , Androgênios/metabolismo , Animais , Masculino , Dados de Sequência Molecular
18.
Fish Shellfish Immunol ; 47(2): 681-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26439414

RESUMO

Toll-like receptors (TLRs) play a critical role in the innate immune system. Although TLR18 is an important member of this family of receptors in fish, the role of the tlr18 gene in responses to pathogen infection is still unclear. In this study, we identified and characterized the grass carp tlr18 gene (gctlr18) to further clarify the function of TLR18 in teleost fish. Gctlr18 spans over 3600 bp and encodes a polypeptide of 852 amino acids. Analysis of the deduced amino acid sequence showed that gctlr18 encodes structures typical of the TLR family, including a signal peptide, seven leucine-rich repeats (LRRs), a transmembrane region, and a (Toll-interleukin-1 receptor) TIR domain. Quantitative RT-PCR analysis showed that gctlr18 was constitutively expressed in all investigated tissues, with abundant expression in spleen, gill, heart, intestine, kidney and fin and low expression in skin, liver and brain. Following grass carp reovirus-challenge and Aeromonas hydrophila inoculation, gctlr18 transcripts were upregulated significantly in immune-relevant tissues. Stimulation of Ctenopharyngodon idella kidney (CIK) cells with purified flagellin from Salmo typhimurium, lipopolysaccharide and polyinosinic-polycytidylic acid stimulation in vitro resulted in significantly increased gctlr18 expression, reaching a peak followed by restoration of normal levels. Overexpression of gctlr18 reduced A. hydrophila invasion by 83.4%. In CIK cells, gctlr18 induced the expression of proinflammatory cytokines, including il-8, inf-1 and tnf-α. Our results indicate that gctlr18 plays a key role in innate immune responses in teleost fish.


Assuntos
Carpas/genética , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Reoviridae/veterinária , Receptores Toll-Like/genética , Aeromonas hydrophila/fisiologia , Animais , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Doenças dos Peixes/genética , Doenças dos Peixes/microbiologia , Doenças dos Peixes/virologia , Proteínas de Peixes/metabolismo , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reoviridae/fisiologia , Infecções por Reoviridae/genética , Infecções por Reoviridae/imunologia , Infecções por Reoviridae/microbiologia , Análise de Sequência de DNA/veterinária , Receptores Toll-Like/metabolismo
19.
Fish Shellfish Immunol ; 36(2): 374-82, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24368222

RESUMO

Relative quantification is the strategy of choice for processing real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) data in microRNA (miRNA) expression studies. Normalization of relative quantification data is performed by comparison to reference genes. In teleost species, such as grass carp (Ctenopharyngodon idella), the determination of reference miRNAs and the optimal numbers of these that should be used has not been widely studied. In the present study, the stability of seven miRNAs (miR-126-3p, miR-101a, miR-451, miR-22a, miR-146, miR-142a-5p and miR-192) was investigated by RT-qPCR in different tissues and in different development stages of grass carp. Stability values were calculated with geNorm, NormFinder, BestKeeper and Delta CT algorithms. The results showed that tissue type is an important variability factor for miRNA expression stability. All seven miRNAs had good stability values and, therefore, could be used as reference miRNAs. When all tissues and developmental stages were considered, miR-101a was the most stable miRNA. When each tissue type was considered separately, the most stable miRNAs were 126-3p in blood and liver, 101a in the gills, 192 in the kidney, 451 in the intestine and 22a in the brain, head kidney, spleen, heart, muscle, skin and fin. 126-3p was the most stable reference miRNA gene during developmental stages 1-5, while 22a was the most stable during developmental stages 6-18. Overall, this study provides valuable information about the reference miRNAs that can be used to perform appropriate normalizations when undertaking relative quantification in RT-qPCR studies of grass carp.


Assuntos
Carpas/genética , Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Carpas/embriologia , Carpas/crescimento & desenvolvimento , Carpas/imunologia , Embrião não Mamífero/metabolismo , Especificidade de Órgãos , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Valores de Referência , Análise de Sequência de DNA/veterinária
20.
J Ultrasound Med ; 33(2): 205-14, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24449722

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the diagnostic performance of contrast-enhanced sonography and acoustic radiation force impulse imaging (ARFI) in differential diagnosis of benign and malignant liver lesions. METHODS: A total of 156 patients with liver lesions were included in the study. The images from conventional sonography and contrast-enhanced sonography and the shear wave velocity values of the liver lesions were obtained. The diagnostic performance of conventional sonography, contrast-enhanced sonography, and ARFI was assessed by using pathologic examination (needle biopsy or surgery) or clinical imaging inspection as the reference standard. RESULTS: The sensitivity and specificity of conventional sonography for malignant liver lesions were 57.1% and 43.1%, respectively, and the sensitivity and specificity of ARFI were 81.3% and 74.1%. When using contrast-enhanced sonography for the diagnosis of malignant liver lesions, the sensitivity and specificity were 92.9% and 89.7%. The sensitivity and specificity of contrast-enhanced sonography were significantly higher than those of ARFI and conventional sonography (P < .05). CONCLUSIONS: The differential diagnostic performance of contrast-enhanced sonography is most predictive of malignant liver lesions. Contrast-enhanced sonography and ARFI have complementary effects in the differential diagnosis of benign and malignant liver lesions.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
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