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1.
Fish Shellfish Immunol ; 145: 109348, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163493

RESUMO

Galectins are lectins that bind to ß-galactose and are widely expressed in immune system tissues, playing pivotal roles in innate immunity through their conserved carbohydrate-recognition domains (CRDs). In this present investigation, a tandem-repeat galectin was discovered in the largemouth bass, Micropterus salmoides (designated as MsGal-9). The open reading frame of MsGal-9 encodes two CRDs, each containing two consensus motifs that are essential for ligand binding. MsGal-9 is expressed in various tissues of the largemouth bass, with particularly high expression levels in the liver and spleen. The full-length form of MsGal-9, as well as the N-terminal (MsGal-9-N) and C-terminal (MsGal-9-C) CRDs, were individually recombined. Their ability for nonself recognition was studied. The three recombinant proteins were able to bind to glucan (GLU), peptidoglycan (PGN), and lipopolysaccharide (LPS), with MsGal-9 displaying the highest binding activity. Furthermore, rMsGal-9-N exhibited higher binding activity towards GLU in comparison to rMsGal-9-C. Further investigations revealed that the full-length rMsGal-9 could significantly bind to Gram-positive bacteria, Gram-negative bacteria, and fungi, while rMsGal-9-C specifically bound to Escherichia coli. However, rMsGal-9-N did not exhibit significant binding activity towards any microbes. These findings indicate that MsGal-9 requires both CRDs to cooperate in order to fulfill its nonself recognition function. All three recombinant proteins demonstrated agglutination activity towards various microbes, with MsGal-9 and MsGal-9-N displaying a similar broad binding spectrum, while MsGal-9-C agglutinated three types of bacteria. Moreover, both MsGal-9 and MsGal-9-N were capable of coagulating largemouth bass red blood cells, whereas MsGal-9-C lacked this ability. However, MsGal-9-C played a significant role in enhancing the encapsulation of leukocytes in comparison to MsGal-9-N. All three proteins acted as potential damage-associated molecular patterns (DAMPs), inducing apoptosis in leukocytes.


Assuntos
Bass , Galectinas , Animais , Galectinas/genética , Bass/metabolismo , Sequência de Aminoácidos , Alinhamento de Sequência , Receptores de Reconhecimento de Padrão/metabolismo , Imunidade Inata , Proteínas Recombinantes , Carboidratos , Filogenia
2.
Int J Mol Sci ; 25(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38732232

RESUMO

C-type lectins in organisms play an important role in the process of innate immunity. In this study, a C-type lectin belonging to the DC-SIGN class of Micropterus salmoides was identified. MsDC-SIGN is classified as a type II transmembrane protein. The extracellular segment of MsDC-SIGN possesses a coiled-coil region and a carbohydrate recognition domain (CRD). The key amino acid motifs of the extracellular CRD of MsDC-SIGN in Ca2+-binding site 2 were EPN (Glu-Pro-Asn) and WYD (Trp-Tyr-Asp). MsDC-SIGN-CRD can bind to four pathogen-associated molecular patterns (PAMPs), including lipopolysaccharide (LPS), glucan, peptidoglycan (PGN), and mannan. Moreover, it can also bind to Gram-positive, Gram-negative bacteria, and fungi. Its CRD can agglutinate microbes and displays D-mannose and D-galactose binding specificity. MsDC-SIGN was distributed in seven tissues of the largemouth bass, among which the highest expression was observed in the liver, followed by the spleen and intestine. Additionally, MsDC-SIGN was present on the membrane of M. salmoides leukocytes, thereby augmenting the phagocytic activity against bacteria. In a subsequent investigation, the expression patterns of the MsDC-SIGN gene and key genes associated with the TLR signaling pathway (TLR4, NF-κB, and IL10) exhibited an up-regulated expression response to the stimulation of Aeromonas hydrophila. Furthermore, through RNA interference of MsDC-SIGN, the expression level of the DC-SIGN signaling pathway-related gene (RAF1) and key genes associated with the TLR signaling pathway (TLR4, NF-κB, and IL10) was decreased. Therefore, MsDC-SIGN plays a pivotal role in the immune defense against A. hydrophila by modulating the TLR signaling pathway.


Assuntos
Aeromonas hydrophila , Bass , Moléculas de Adesão Celular , Doenças dos Peixes , Transdução de Sinais , Animais , Aeromonas hydrophila/imunologia , Bass/imunologia , Bass/metabolismo , Bass/microbiologia , Bass/genética , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/metabolismo , Proteínas de Peixes/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Imunidade Inata , Lectinas Tipo C/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Moléculas com Motivos Associados a Patógenos/metabolismo , Moléculas com Motivos Associados a Patógenos/imunologia , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/genética , Receptores Toll-Like/metabolismo , Receptores Toll-Like/genética
3.
Fish Shellfish Immunol ; 134: 108614, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36775183

RESUMO

Peptidoglycan (PGN) recognition proteins (PGRPs) are important immune factors in innate immunity that function in recognising pathogens and activating the immune system. These ubiquitous proteins are conserved in invertebrates and vertebrates. In this study, a PGRP gene (MsPGRP) from largemouth bass (Micropterus salmoides) was identified and characterised, and its transcription distribution was explored. Recombinant protein (rMsPGRP) exhibited dose-dependent binding to PGN and glucan (GLU), but weak binding to lipopolysaccharide (LPS). MsPGRP exhibited agglutinating activity against several Gram-negative bacteria, Gram-positive bacteria and fungi, and it promoted phagocytosis activity of leukocytes against Micrococcus luteus and Aeromonas hydrophila. The protein also possessed amidase activity in the presence of Zn2+, degraded PGN, and disrupted the M. luteus cell wall. The results suggest that MsPGRP plays an important role in pathogen recognition, and acts as a opsonin during immune system responses and elimination of invading pathogens.


Assuntos
Bass , Animais , Proteínas de Transporte/genética , Imunidade Inata/genética , Proteínas Recombinantes , Peptidoglicano/metabolismo
4.
Fish Shellfish Immunol ; 132: 108488, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36503056

RESUMO

Phagocytosis is an important innate immune process in which immune cells recognize, ingest and eliminate pathogens. Largemouth bass (Micropterus salmoides) has become an important economic farmed fish in many regions, while few studies has focused on phagocytosis of its leucocytes. In present study, largemouth bass peripheral blood leucocytes were separated using Percoll gradient to establish the phagocytic function. Flow cytometric analysis showed that largemouth bass leukocytes exhibited the phagocytic capacity to fluoresbrite microspheres and Aeromonas hydrophila, where higher phagocytic capacity to A. hydrophila were observed in granulocytes/monocytes than that of lymphocytes. The leukocytes engulfing fluoresbrite microspheres and A. hydrophila were also observed by fluorescence microscopy. Besides, manygenes associated with phagocytosis and TNF-α in leukocytes were up-regulated following A. hydrophila stimulation. Subsequently, the largemouth bass TNF-α was recombinantly expressed to investigate its role in regulating phagocytosis. The results showed that TNF-α in largemouth bass could significantly enhance the phagocytic ability of granulocytes/monocytes to A. hydrophila, but not lymphocytes. Moreover, we also found that TNF-α could not only significantly increase the ROS activity of granulocytes/monocytes, but also had the function of inducing its apoptosis. These results demonstrated that granulocytes/monocytes play more important role in phagocytosis, meanwhile, TNF-α has the function of enhancing the phagocytic ability of granulocytes/monocytes in largemouth bass.


Assuntos
Bass , Animais , Bass/genética , Fator de Necrose Tumoral alfa/genética , Fagocitose , Leucócitos
5.
Fish Shellfish Immunol ; 139: 108922, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37393061

RESUMO

Largemouth bass (Micropterus salmoides) is an important economic freshwater aquaculture fish originating from North America. However, the frequent outbreaks of Micropterus salmoides rhabdovirus (MSRV) have seriously limited the healthy development of Micropterus salmoides farming industry. In the present study, a strain of MSRV was isolated and identified from infected largemouth bass by PCR, transmission electron micrograph observation and genome sequences analysis, and tentatively named MSRV-HZ01 strain. Phylogenetic analyses showed that the MSRV-HZ01 presented the highest similarity to MSRV-2021, followed by MSRV-FJ985 and MSRV-YH01. The various tissues of juvenile largemouth bass exhibited significant pathological damage following MSRV-HZ01 immersion infection, and the mortality reached 90%. We also found that intestine was the key organ for MSRV to enter the fish body initially by dynamic analysis of viral infection, and the head kidney was the susceptible tissue of virus. Moreover, the MSRV was also transferred to the external mucosal tissue in later stage of viral infection to achieve horizontal transmission. In addition, the genes of IFN γ and IFN I-C were significantly up-regulated after MSRV infection to exert antiviral functions. The genes of cGAS and Sting might play an important role in the regulation of interferon expression. In conclusion, we investigated the virus infection dynamics and fish response following MSRV immersion infection, which would promote our understanding of the interaction between MSRV and largemouth bass under natural infection.


Assuntos
Bass , Doenças dos Peixes , Rhabdoviridae , Viroses , Animais , Bass/genética , Filogenia , Imersão
6.
Org Biomol Chem ; 20(32): 6459-6463, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35894817

RESUMO

A mild and efficient visible-light-induced radical method was developed to produce C3-malonated five-membered heterocycles using 2-substituted thiophenes/furans and diethyl bromomalonate as the starting materials. Various 2-substituted (benzo)thiophenes/furans were suitable for the C3-ethoxycarbonylmethylation. The free radical mechanism was proposed based on the results of control experiments, cyclic voltammetry experiments and luminescence quenching experiments. We suggested that the heteroleptic halogen-bridged iridium(III) dimers might play an important role in this system.


Assuntos
Furanos , Tiofenos , Luz , Estrutura Molecular
7.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36142687

RESUMO

The improper components of formulated feed can cause the intestinal dysbiosis of juvenile largemouth bass and further affect fish health. A 28 day feeding trial was conducted to investigate the effect of partially replacing fish meal (FM) with autolyzed Yarrowia lipolytica (YL) on juvenile largemouth bass (Micropterus salmoides). We considered four diets-control, YL25, YL50, and YL75-in which 0%, 25%, 50%, and 75% of the FM content, respectively, was replaced with YL. According to results, the weight gain rate (WGR) and specific growth rate (SGR) of the fish with the YL25 and YL50 diets were significantly higher than the WGR and SGR with the control diet, while the YL75 diet significantly reduced fish growth and antioxidant enzymes activities, and shortened the villus height in the intestinal mucosa. The 16S rRNA analysis of the intestinal microbiota showed that the relative abundance of Mycoplasma was significantly increased with the YL25 and YL50 diets, while the Enterobacteriacea content was increased with the YL75 diet. Moreover, our transcriptome analysis revealed that certain differentially expressed genes (DEGs) that are associated with growth, metabolism, and immunity were modulated by YL inclusion treatment. Dietary YL25 and YL50 significantly reduced the mRNA level of ERBB receptor feedback inhibitor 1 (errfi1) and dual-specificity phosphatases (dusp), while the expression of the suppressor of cytokine signaling 1 (socs1), the transporter associated with antigen processing 2 subunit type a (tap2a), and the major histocompatibility complex class I-related gene (MHC-I-l) were sharply increased with YL75 treatment. We determined that the optimum dose of dietary YL required for maximum growth without any adverse influence on intestinal health was 189.82 g/kg (with 31.63% of the fishmeal replaced by YL), while an excessive substitution of YL for fishmeal led to suppressed growth and antioxidant capacity, as well as intestinal damage for juvenile largemouth bass.


Assuntos
Bass , Microbioma Gastrointestinal , Yarrowia , Animais , Antioxidantes/metabolismo , Bass/metabolismo , Citocinas/metabolismo , Fosfatases de Especificidade Dupla/metabolismo , Receptores ErbB/metabolismo , RNA Mensageiro/metabolismo , RNA Ribossômico 16S/metabolismo , Transcriptoma , Yarrowia/genética , Yarrowia/metabolismo
8.
J Biol Chem ; 295(31): 10638-10652, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32518157

RESUMO

Infections by many bacterial pathogens rely on their ability to degrade host glycans by producing glycoside hydrolases (GHs). Here, we discovered a conserved multifunctional GH, SsGalNagA, containing a unique combination of two family 32 carbohydrate-binding modules (CBM), a GH16 domain and a GH20 domain, in the zoonotic pathogen Streptococcus suis 05ZYH33. Enzymatic assays revealed that the SsCBM-GH16 domain displays endo-(ß1,4)-galactosidase activity specifically toward the host-derived αGal epitope Gal(α1,3)Gal(ß1,4)Glc(NAc)-R, whereas the SsGH20 domain has a wide spectrum of exo-ß-N-acetylhexosaminidase activities, including exo-(ß1,3)-N-acetylglucosaminidase activity, and employs this activity to act in tandem with SsCBM-GH16 on the αGal-epitope glycan. Further, we found that the CBM32 domain adjacent to the SsGH16 domain is indispensable for SsGH16 catalytic activity. Surface plasmon resonance experiments uncovered that both CBM32 domains specifically bind to αGal-epitope glycan, and together they had a KD of 3.5 mm toward a pentasaccharide αGal-epitope glycan. Cell-binding and αGal epitope removal assays revealed that SsGalNagA efficiently binds to both swine erythrocytes and tracheal epithelial cells and removes the αGal epitope from these cells, suggesting that SsGalNagA functions in nutrient acquisition or alters host signaling in S. suis Both binding and removal activities were blocked by an αGal-epitope glycan. SsGalNagA is the first enzyme reported to sequentially act on a glycan containing the αGal epitope. These findings shed detailed light on the evolution of GHs and an important host-pathogen interaction.


Assuntos
Proteínas de Bactérias/química , Epitopos/química , Glicosídeo Hidrolases/química , Polissacarídeos Bacterianos/química , Streptococcus suis/química , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Dissacarídeos/química , Dissacarídeos/genética , Dissacarídeos/metabolismo , Epitopos/genética , Epitopos/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Camundongos , Polissacarídeos Bacterianos/genética , Polissacarídeos Bacterianos/metabolismo , Domínios Proteicos , Coelhos , Streptococcus suis/genética , Streptococcus suis/metabolismo , Suínos
9.
Langmuir ; 37(31): 9396-9404, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34324346

RESUMO

In the manufacture of the emissive layer and the encapsulation layer of organic light-emitting diode panels, inkjet printing has the advantages of high material utilization, low cost, flexibility in patterning, and large-area production. Especially for emissive layer printing, the micro-pixel array brings a higher requirement of droplet positioning accuracy and volume of the liquid in a pixel. To achieve a uniform deposit morphology, several droplets are usually needed in the inkjet printing of emissive layers. As the printing process continues, these droplets coalesce, and its equilibrium outcome can be roughly approximated by a section of an ellipsoidal cap under the interaction of the surface tension and gravity. The existence of the "ellipsoidal cap" enlarges the spread, and the maximum allowable out-of-pixel spreading length is decreased because of the "ellipsoidal cap" in the neighboring pixel. In this research, the volume of fluid method is used to study the behavior of the last droplet deposition into the wetted microcavity. The effects of wettability, droplet deposition speed, and initial volume of the liquid in the pixel on the printable region are investigated, and printing parameter spaces that result in successful printing are established.

10.
J Immunol ; 203(7): 1845-1856, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31484728

RESUMO

The immune signaling pathway mediated by Dectin-1 is important in mammals to modulate the production of IL-17 and TNF-α. Recently, IL-17 and TNF have also been characterized in invertebrates to play crucial roles in antibacterial immune responses, although the immune recognition and regulation mechanisms to produce IL-17 and TNF are still not well investigated. In the current study, a novel C-type lectin receptor (named CgCLec-HTM) with a signal peptide, a carbohydrate recognition domain, a transmembrane domain, and a nonclassical ITAM (hemITAM) in the cytoplasmic tail was identified from oyster Crassostrea gigas CgCLec-HTM could bind LPS and various bacteria. After binding to its ligands, CgCLec-HTM was associated with the Src homology 2 (SH2) domain of spleen tyrosine kinase (CgSyk) by the hemITAM in its cytoplasmic tail to promote ERK (CgERK) phosphorylation. The activated CgERK could interact with CgRel to induce CgRel nuclear translocation. The CgRel in the nucleus eventually induced the transcription of CgIL-17s and CgTNF. The results demonstrated that CgCLec-HTM with a broad binding spectrum of bacteria could be associated with CgSyk to transfer immune signals into the intracellular ERK-Rel pathway to induce CgIL-17 and CgTNF production.


Assuntos
Crassostrea/imunologia , Interleucina-17/imunologia , Lectinas Tipo C/imunologia , Lipopolissacarídeos/farmacologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/imunologia , Animais , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
11.
J Org Chem ; 85(23): 15051-15061, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33147963

RESUMO

Despite the various attractive properties of γ-pyrones, there are still some deficiencies in their synthetic approaches such as lower atom economy, multistep processes, and prefunctionalization of the reagents. In this work, an efficient and simple (CF3CO)2O/CF3SO3H-mediated "one-pot" approach was realized to produce γ-pyrones by applying aromatic ketones/heteroarenes and carboxylic acids as the starting materials. The target products were isolated in moderate to excellent yields. The reaction mechanism was studied by density functional theory calculational methods. The results of experimental and theoretical investigations not only helped us explain the reason of high selectivity formation of ß-diketones but also proved that 1,3,5-ketones might be important intermediates for the cyclization to afford γ-pyrones.

12.
Fish Shellfish Immunol ; 96: 152-160, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31794843

RESUMO

C-type lectins are Ca2+-dependent carbohydrate-binding proteins containing one or more carbohydrate-recognition domains (CRDs). C-type lectins play crucial roles in innate immunity, including nonself-recognition and pathogen elimination. In the present study, two C-type lectins (designated ReCTL-1 and ReCTL-2) were identified from the shrimp Rimicaris exoculata which dwells in deep-sea hydrothermal vents. The open reading frames of ReCTL-1 and ReCTL-2 encoded polypeptides of 171 and 166 amino acids respectively, which were both composed of a signal peptide and a single CRD. The key motifs determining the carbohydrate binding specificity of ReCTL-1 and ReCTL-2 were respectively Glu-Pro-Ala (EPA) and Gln-Pro-Asn (QPN), which were firstly discovered in R. exoculata. ReCTL-1 and ReCTL-2 displayed similar pathogen-associated molecular pattern (PAMP) binding features and they bound three PAMPs-ß-glucan, lipopolysaccharide and peptidoglycan-with relatively high affinity. In addition, both could efficiently recognize and bind Gram-positive bacteria, Gram-negative bacteria and fungi. However, ReCTL-1 and ReCTL-2 exhibited different microbial agglutination activities: ReCTL-1 agglutinated Staphylococcus aureus and Saccharomyces cerevisiae, while ReCTL-2 agglutinated Micrococcus luteus, Vibrio parahaemolyticus and V. fluvialis. Both ReCTL-1 and ReCTL-2 inhibited the growth of V. fluvialis. All these results illustrated that ReCTL-1 and ReCTL-2 could function as important pattern-recognition receptors with broad nonself-recognition spectra and be involved in immune defense against invaders, but their specificities are not the same. In addition, the two ReCTLs possessed different carbohydrate binding specificities from each other and from the classical pattern: ReCTL-1 with an EPA motif bound d-galactose and l-mannose, while ReCTL-2 with a QPN motif bound d-fucose and N-acetylglucosamine.


Assuntos
Decápodes/genética , Decápodes/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Sequência de Bases , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Lectinas Tipo C/química , Filogenia , Receptores de Reconhecimento de Padrão/metabolismo , Alinhamento de Sequência
13.
Org Biomol Chem ; 18(17): 3346-3353, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32301954

RESUMO

A mild and simple one-pot stepwise method to synthesize 3-arylacetylene coumarins from alkynoates was demonstrated. This catalytic system involves photosensitizer-free photocatalysis and thermocatalysis processes. A series of alkynoates and phenylacetylenes were well tolerated in the optimized multi-catalytic system. The corresponding 3-arylacetylene coumarins were obtained in moderate to excellent yields. The results of the studies of their optical properties showed that the aromatic ring at the C4-position of coumarins is unfavorable for improving the molecular fluorescence quantum yield in solution. Based on the spectral studies and X-ray single crystal diffraction analysis, it was found that AIE activities may exist in some of the 3-arylvinyl-4-aryl-coumarins in their solid state. We expect that these molecules may have potential optical applications.

14.
Mol Pharm ; 16(12): 4826-4835, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31663764

RESUMO

Tumor-targeted ligand modification and nanosized coloaded drug delivery systems are promising for cancer therapy. In this study, we showed that coix seed oil and tripterine coloaded microemulsions with a transferrin modification (Tf-CT-MEs) could improve the treatment of cervical cancer. Tf-CT-MEs exhibited good stability in serum and a notably synergistic antiproliferation effect. In the HeLa xenograft tumor-bearing mouse model, Tf-CT-MEs accumulated at tumor sites and penetrated deeply in tumor tissues. Tf-CT-MEs had superior anticancer efficacy in vivo, which greatly slowed the growth of tumors (***p < 0.001 vs saline). We also found that Tf-CT-MEs inhibited tumor cell proliferation, enhanced antiangiogenesis, and induced apoptosis by regulating bax/bcl-2 and the activating caspase-3 pathway. Tf-CT-MEs decreased by 27.7, 26.9, 61.2, and 42.5% of concentrations of TGF-ß1, CCL2, TNF-α, and IL-6 in serum, respectively. In addition, Tf-CT-MEs showed little toxicity in vital organs. These results were due to the improved drug delivery efficiency. Collectively, Tf-CT-MEs enhance tumor-targeting, facilitate deep penetration of drugs, and have promising potential as an efficient treatment for cervical cancer.


Assuntos
Coix/química , Emulsões/farmacologia , Óleos de Plantas/farmacologia , Sementes/química , Transferrina/farmacologia , Triterpenos/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Triterpenos Pentacíclicos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
15.
Fish Shellfish Immunol ; 84: 704-710, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30359751

RESUMO

Japanese eel (Anguilla japonica) has become a commercially important fish species all over the world. High-density aquaculture has led to congestion and contributed to bacterial infection outbreaks that have caused high mortality. Therefore a 56-days feeding trial was conducted to determine the effects of dietary Bacillus amyloliquefaciens (GB-9) and Yarrowia lipolytica lipase2 (YLL2) on growth performance, digestive enzymes activity, innate immunity and resistance to pathogens of A. japonica. Fish growth performance was significantly affected by dietary YLL2 supplementation but not by GB-9. Fish fed diets with YLL2 at 2.0 g/kg diet in combination of high and low levels of GB-9 (5.0 g/kg and 2.0 g/kg) produced the highest growth. For digestive enzyme, lipase and trypsin activities was promoted by dietary containing YLL2, while amylase activities was increased by dietary containing YLL2, GB-9 single or combination. For innate immunity, the mucus lysozyme activity, leukocytes phagocytosis activity and reactive oxygen species level of skin, peroxidase and lysozyme activity of serum were enhanced in fish fed with GB-9 compared to those in control group (p < 0.05). The highest resistance to Vibrio anguillarum and Aeromonas hydrophila was determined in fish fed with 5.0 g kg-1 GB-9 + 2.0 g/kg YLL2. This study demonstrated that GB-9 and YLL2 enhanced non-specific immune defense system of A. japonica, providing them with higher resistance to pathogens. The present results suggested that the combination of these supplements could be considered as potential biological additives for aquaculture farmed fish.


Assuntos
Anguilla/imunologia , Bacillus amyloliquefaciens/química , Hidrolases de Éster Carboxílico/administração & dosagem , Doenças dos Peixes/imunologia , Proteínas Fúngicas/administração & dosagem , Imunidade Inata/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Probióticos/farmacologia , Aeromonas hydrophila/fisiologia , Anguilla/crescimento & desenvolvimento , Anguilla/metabolismo , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Trato Gastrointestinal/enzimologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Distribuição Aleatória , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
16.
Org Biomol Chem ; 17(18): 4621-4628, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31017597

RESUMO

An efficient one-pot stepwise method to synthesize 3-styryl-4-arylcoumarins from simple alkynoates is demonstrated. On the basis of the control experiments, a possible mechanism involving light-driven radical cyclization and Pd-catalysed cross-coupling processes for this synthesis method is proposed. The results of X-ray analysis and spectroscopy experiments prove that the substituent effect has a significant influence on the absorption and emission properties of the synthesized 3-styryl coumarins.

17.
Environ Sci Technol ; 53(7): 3610-3619, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30835446

RESUMO

The application of tandem catalysis is rarely investigated in degrading organic pollutants in the environment. Herein, a tandem catalyst on single platinum (Pt) nanoparticles (Pt0 NPs) is prepared for the sequential degradation of formaldehyde (HCHO) to carbon dioxide gas [CO2(g)] at room temperature. The synthesis approach includes coating of uniform Pt NPs on SrBi2Ta2O9 platelets using a photoreduction process, followed by calcination of the sample in the atmosphere to tune partial transformation of Pt0 atoms to Pt2+ ions in the tandem catalyst. The conversion of HCHO to CO2(g) is monitored by in situ Fourier transform infrared spectroscopy, which shows first conversion of HCHO to CO32- ions onto Pt0 active sites and subsequently the conversion of CO32- ions to CO2(g) by neighboring Pt2+ species of the catalyst. The later process with Pt2+ species does not allow CO32- poisoning of the catalyst. The enhanced activity of the prepared tandem catalyst to oxidize HCHO is maintained continuously for 680 min. Comparatively, the catalyst without Pt2+ shows activity for only 40 min. Additionally, the tandem catalyst presented herein performs better than the Pt/titanium dioxide (TiO2) catalyst to degrade HCHO. Overall, the tandem catalyst may be applied to degrade organic pollutants efficiently.


Assuntos
Nanopartículas Metálicas , Platina , Catálise , Domínio Catalítico , Formaldeído , Oxirredução , Temperatura
18.
Int J Syst Evol Microbiol ; 68(1): 409-415, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29219804

RESUMO

A Gram-stain-negative, rod-shaped bacterium, designated 157T, was isolated from seawater collected from the Philippine Sea. Cells of strain 157T grew in medium containing 0.5-10.0 % NaCl (w/v, optimum 3 %), at pH 6.0-8.5 (optimum 7.0) and at 15-40 °C (optimum 30 °C). Tweens 20, 40 and 80 as well as urea were hydrolysed. The 16S rRNA gene sequence of strain 157T had a high sequence similarity with respect to Pseudooceanicola marinus AZO-CT (97.2 %), and exhibited less than 97.0 % sequence similarity to other type strains of the species with validly published names. Phylogenetic analyses revealed that strain 157T fell within a cluster comprising the Pseudooceanicola species and formed a coherent clade with P. marinus AZO-CT and Pseudooceanicola antarcticus Ar-45T. Strain 157T exhibited average nucleotide identity values of 74.5 and 74.9 % to P. marinus LMG 23705T and P. antarcticus Ar-45T, respectively. In silico DNA-DNA hybridization analysis revealed that strain 157T shared 20.2 % DNA relatedness with P. marinus LMG 23705T and 20.6 % with P. antarcticus Ar-45T, respectively. The sole isoprenoid quinone was ubiquinone 10. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C19 : 0 cyclo ω8c, C16 : 0 2-OH and C16 : 0. The major polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminolipid and one unidentified glycolipid. The DNA G+C content was 64.6 mol%. According to the phylogenetic, chemotaxonomic and phenotypic data, it represents a novel species of the genus Pseudooceanicola, for which the name Pseudooceanicolalipolyticus is proposed. The type strain is 157T (=KCTC 52654T=MCCC 1K03317T). In addition, the description of the genus Pseudooceanicola is emended and Oceanicola flagellatus is reclassified as Pseudooceanicola flagellatus comb. nov., with the type strain DY470T (=CGMCC 1.12664T=LMG 27871T) proposed.


Assuntos
Filogenia , Rhodobacteraceae/classificação , Água do Mar/microbiologia , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Filipinas , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/química
19.
Fish Shellfish Immunol ; 82: 250-257, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30125703

RESUMO

A 12-weeks feeding trial was performed to investigate the possible effects of supplementation of Hybrid sturgeon diet with Bacillus amyloliquefaciens (GB-9) and Yarrowia lipolytica lipase2 (YLL2) single or combined on immune response and growth performance of Hybrid sturgeon (Acipenser schrenkii ♂and Acipenser baeri ♀). For this aim, Hybrid sturgeons were fed with four experimental diets namely: Diet 1 (0-control), Diet 2 (5.0 g/kg GB-9), Diet 3 (4.0 g/kg YLL2), and Diet 4 (5.0 g/kg GB-9 + 4.0 g/kg YLL2), respectively. After fed with varied diets, growth performance, mucosal immune response, leukocytes immune response and serum immunological response were measured. The results indicated that supplementations of GB-9 + YLL2 resulted in a significant increase in final weight, Docosahexaenoic acid (DHA) and Eicosapentenoic acid (EPA) concentration, compared with that of control (p < 0.05). For innate immunity, the results showed that skin mucus lysozyme activity, leukocytes phagocytosis activity and reactive oxygen species level, and serum alternative complement pathway activity, peroxidase and lysozyme activity were significantly higher in supplemented groups compared to the control (p < 0.05). The highest values were recorded in fish fed both YLL2 and GB-9 with respect to the individual application. The present results suggested that the combination of these supplementation could be considered as potential feed-additives for aquaculture farmed fish.


Assuntos
Bacillus amyloliquefaciens/química , Hidrolases de Éster Carboxílico/administração & dosagem , Peixes/crescimento & desenvolvimento , Peixes/imunologia , Proteínas Fúngicas/administração & dosagem , Probióticos/farmacologia , Ração Animal/análise , Animais , Cruzamento , Dieta/veterinária , Suplementos Nutricionais/análise , Imunidade Inata/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Distribuição Aleatória
20.
Fish Shellfish Immunol ; 78: 238-247, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29678793

RESUMO

Galectins are ß-galactoside binding lectins that play crucial roles in innate immunity in vertebrates and invertebrates through their conserved carbohydrate-recognition domains (CRDs). In the present study, single- and four-CRD-containing galectins were identified in oyster Crassostrea gigas (designated CgGal-2 and CgGal-3). The open reading frames (ORFs) of CgGal-2 and CgGal-3 encode polypeptides of 200 and 555 amino acids, respectively. All CRDs of CgGal-3 include two consensus motifs essential for ligand-binding, and a novel motif is present in CgGal-2. Pathogen-associated molecular pattern (PAMP) profiles were determined for recombinant rCgGal-2 and rCgGal-3, and rCgGal-2 displayed low binding affinity for PAMPs, while rCgGal-3 bound various PAMPs including glucan, lipopolysaccharide (LPS), and peptidoglycan (PGN) with relatively high affinity. Furthermore, rCgGal-2 and rCgGal-3 exhibited different microbe binding profiles; rCgGal-2 bound to Gram-negative bacteria (Escherichia coli and Vibrio vulnificus) and fungi (Saccharomyces cerevisiae and Pichia pastoris), while rCgGal-3 bound to these microbes but also to Gram-positive bacteria (Micrococcus luteus). In addition, rCgGal-3 possessed microbial agglutinating activity and coagulation activity against fungi and erythrocytes, respectively, but rCgGal-2 lacked any agglutinating activity. Carbohydrate binding specificity analysis showed that rCgGal-3 specifically bound D-galactose. Furthermore, rCgGal-2 and rCgGal-3 functioned as opsonin participating in the clearance against invaders in C. gigas. Thus, CgGal-2 with one CRD and CgGal-3 with four CRDs are new members of the galectin family involved in immune responses against bacterial infection. Differences in the organisation and amino acid sequences of CRDs may affect their specificity and affinity for nonself substances.


Assuntos
Crassostrea/genética , Galectina 2/genética , Galectina 3/genética , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Sequência de Aminoácidos , Animais , Crassostrea/imunologia , Fungos/fisiologia , Galectina 2/química , Galectina 2/imunologia , Galectina 3/química , Galectina 3/imunologia , Perfilação da Expressão Gênica , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Filogenia , Alinhamento de Sequência
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