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1.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
2.
Plast Reconstr Surg ; 144(1S Utilizing a Spectrum of Cohesive Implants in Aesthetic and Reconstructive Breast Surgery): 13S-20S, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31246756

RESUMO

Two important topics in breast augmentation and reconstruction relate to device surface texture and practices to mitigate biofilm contamination of implants. Breast augmentation can be considered a manufacturing process where planning concepts of process engineering and quality can be used to produce great outcomes. This article reviews the options available for surgeons with regards to device surface texture selection and practices to mitigate biofilm contamination of implants at the time of surgery.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Biofilmes/efeitos dos fármacos , Implante Mamário/efeitos adversos , Implantes de Mama/microbiologia , Infecções Relacionadas à Prótese/prevenção & controle , Implante Mamário/instrumentação , Implante Mamário/métodos , Feminino , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/patogenicidade , Bactérias Gram-Positivas/fisiologia , Humanos , Povidona-Iodo/administração & dosagem , Infecções Relacionadas à Prótese/etiologia , Propriedades de Superfície , Irrigação Terapêutica
3.
Fish Shellfish Immunol ; 90: 446-455, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31002928

RESUMO

Adiponectin (APN) is an important cytokine secreted by fat cells that is responsible for regulating numerous biological functions. However, the APN gene in lamprey and its precise function remain unidentified. In this study, the full-length cDNA sequence of L-APN was cloned, and it encoded a protein of 267 amino acid residues with a globular domain. The results of immunohistochemistry and FACS assays showed that APN protein was distributed in multiple tissues. L-APN expression in the supraneural body (SB) and leukocytes was differentially upregulated in response to Gram-negative bacteria, Gram-positive bacteria and poly (I:C). The expression levels of inflammatory cytokines were upregulated, and a proapoptotic effect was stimulated in SB cells treated with recombinant APN. Furthermore, L-APN could inhibit cell proliferation and arrest cell growth in the G1 phase. In summary, the APN protein from the lamprey plays an important role in inhibiting cell proliferation, inducing the production of inflammatory cytokines and promoting cell apoptosis, and it is also involved in immune responses and immune defenses. Our data provide insights into the evolutionary origin of the structure and function of APN gene.


Assuntos
Adiponectina/genética , Adiponectina/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lampreias/genética , Lampreias/imunologia , Adiponectina/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Citocinas/genética , Citocinas/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Inflamação/imunologia , Inflamação/veterinária , Filogenia , Poli I-C/farmacologia , Alinhamento de Sequência/veterinária
4.
Microbiol Spectr ; 7(2)2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31025623

RESUMO

In this article, we explore the unique adaptations of intracellular bacterial pathogens that manipulate conserved cellular pathways, organelles, and cargo to convert the phagosome into a pathogen-containing vacuole (PCV). The phagosome is a degradative organelle that rapidly acidifies as it delivers cargo to the lysosome to destroy microbes and cellular debris. However, to avoid this fate, intracellular bacterial pathogens hijack the key molecular modulators of intracellular traffic: small GTPases, phospholipids, SNAREs, and their associated effectors. Following uptake, pathogens that reside in the phagosome either remain associated with the endocytic pathway or rapidly diverge from the preprogrammed route to the lysosome. Both groups rely on effector-mediated mechanisms to meet the common challenges of intracellular life, such as nutrient acquisition, vacuole expansion, and evasion of the host immune response. Mycobacteria, Salmonella, and Coxiella serve as a lens through which we explore regulators of the canonical endocytic route and pathogens that seek to subvert it. On the other hand, pathogens such as Chlamydia, Legionella, and Brucella disconnect from the canonical endocytic route. This bifurcation is linked to extensive hijacking of the secretory pathway and repurposing of the PCV into specialized compartments that resemble organelles in the secretory network. Finally, each pathogen devises specific strategies to counteract host immune responses, such as autophagy, which aim to destroy these aberrant organelles. Collectively, each unique intracellular niche and the pathogens that construct them reflect the outcome of an aggressive and ongoing molecular arms race at the host-pathogen interface. Improving our understanding of these well-adapted pathogens can help us refine our knowledge of conserved cell biological processes.


Assuntos
Endocitose/fisiologia , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/fisiologia , Bactérias Gram-Positivas/patogenicidade , Proteínas de Bactérias/metabolismo , Transporte Biológico , GTP Fosfo-Hidrolases/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Lisossomos/fisiologia , Fagocitose/fisiologia , Fagossomos/fisiologia , Vacúolos/fisiologia
5.
Microbiol Spectr ; 7(2)2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31004421

RESUMO

The main strategies used by pathogenic bacteria to infect eukaryotic tissue include their adherence to cells and the extracellular matrix (ECM), the subsequent colonization and invasion as well as the evasion of immune defences. A variety of structurally and functionally characterized adhesins and binding proteins of gram-positive bacteria facilitate these processes by specifically recognizing and interacting with various components of the host ECM, including different collagens, fibronectin and other macromolecules. The ECM affects the cellular physiology of our body and is critical for adhesion, migration, proliferation, and differentiation of many host cell types, but also provides the support for infiltrating pathogens, particularly under conditions of injury and trauma. Moreover, microbial binding to a variety of adhesive components in host tissue fluids leads to structural and/or functional alterations of host proteins and to the activation of cellular mechanisms that influence tissue and cell invasion of pathogens. Since the diverse interactions of gram-positive bacteria with the ECM represent important pathogenicity mechanisms, their characterization not only allows a better understanding of microbial invasion but also provides clues for the design of novel therapeutic strategies to manage infectious diseases.


Assuntos
Matriz Extracelular/microbiologia , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Animais , Aderência Bacteriana , Fibronectinas/genética , Fibronectinas/metabolismo , Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/metabolismo , Humanos
6.
Biofouling ; 35(2): 187-203, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30913919

RESUMO

Biofilm related bacterial infection is one of the primary causes of implant failure. Limiting bacterial adhesion and colonization of pathogenic bacteria is a challenging task in health care. Here, a highly simplistic processing technique for imparting antibacterial properties on a biomedical grade stainless steel is demonstrated. Low-temperature high strain-rate deformation achieved using submerged friction stir processing resulted in a nearly single phase ultra-fine grain structure. The processed stainless steel demonstrated improved antibacterial properties for both Gram-positive and Gram-negative bacteria, significantly impeding biofilm formation during the in vitro study. Also, the processed stainless steel showed better compatibility with human fibroblasts manifested through apparent cell spreading and proliferation. The substantial antibacterial properties of the processed steel are explained in terms of the favorable electronic characteristics of the metal-oxide and by using classical Derjaguin-Landau-Verwey-Overbeek (DLVO) and the extended DLVO (XDLVO) approach at the cell-substrate interface.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fricção , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Aço Inoxidável/química , Aderência Bacteriana/fisiologia , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Humanos , Propriedades de Superfície
7.
Prep Biochem Biotechnol ; 49(5): 477-484, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30896323

RESUMO

Polymicrobial biofilms often form on the surfaces of food-processing machinery, causing equipment damage and posing a contamination risk for the foods processed by the system. The composition of the microbial communities that make up these biofilms is largely unknown, especially in the dairy industry. To address this deficit, we investigated the bacterial composition of biofilms that form on the surfaces of equipment during dairy processing using Illumina MiSeq sequencing and culture-dependent methods. Illumina sequencing identified eight phyla, comprising six classes, ten orders, fifteen families, eighteen genera, and eighteen species. In contrast, only eight species were isolated from the same samples using the culture-based method. To determine the ability of the identified bacteria to form biofilms, biofilm formation analysis via crystal violet staining was performed. Five of the eight culturable species, Acinetobacter baumannii, Acinetobacter junii, Enterococcus faecalis, Corynebacterium callunae, and Stenotrophomonas maltophilia, were able to form biofilms. Since most of the identified bacteria are potential food-borne or opportunistic pathogens, this study provides guidance for quality control of products produced in dairy processing facilities.


Assuntos
Biofilmes , Indústria de Laticínios/instrumentação , Contaminação de Equipamentos , Equipamentos e Provisões/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Técnicas de Tipagem Bacteriana/métodos , Técnicas de Cultura de Células/métodos , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/fisiologia , Microbiota/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos
8.
Int J Infect Dis ; 81: 210-214, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30794940

RESUMO

Dalbavancin, a lipoglycopeptide with prolonged half-life approved for the treatment of acute bacterial skin and soft tissue infections, can be used for the treatment of infections caused by gram-positive bacteria requiring long term treatment such as endocarditis, prosthetic joint infections (PJI) or osteomyelitis. Clinical data are limited in these settings. OBJECTIVES: To evaluate indications, safety, tolerability and long-term outcomes of dalbavancin-treated patients. Patients and methods Our multicenter, retrospective study includes patients who received dalbavancin in Austria from September 2016 to March 2018. 90-day outcomes and tolerability were determined. RESULTS: A total of 101 patients were included in 3 centers (57% male, median age 65 years). The treated infections were PJI (31%), osteomyelitis (29%), endocarditis (25%) and acute bacterial skin and soft tissue infections (12%). Concomitant use of other antimicrobial substances was common (63%). The mean total cumulative dose of dalbavancin was 3,357mg (±2,283mg). Clinical success rate was 89%. Side effects occurred in 3/101 patients. CONCLUSION: In this real-life study dalbavancin was primarily used in off-label indications for treatment of PJI, osteomyelitis and endocarditis. Success rate was high (89%), tolerability and safety were excellent in this setting. Dalbavancin may therefore be used in these off-label indications as alternative treatment approach.


Assuntos
Antibacterianos/administração & dosagem , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Teicoplanina/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Áustria , Criança , Feminino , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/isolamento & purificação , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteomielite/microbiologia , Estudos Retrospectivos , Infecções dos Tecidos Moles/tratamento farmacológico , Infecções dos Tecidos Moles/microbiologia , Teicoplanina/administração & dosagem , Teicoplanina/efeitos adversos , Adulto Jovem
9.
Fish Shellfish Immunol ; 87: 582-589, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30711491

RESUMO

Protein enhancer of sevenless 2B, E(sev)2B, is a key adapter protein in the Ras/MAPK signaling pathway which has been reported to be involved in innate immunity. In this study, the gene that encodes AsE(sev)2B was isolated from A. sinica. It was found to contain a 636 bp open reading frame encoding 211 amino acids with a calculated molecular mass of 24.357 kDa and a predicted isoelectric point of 5.39. The predicted protein contains a N-terminal Src homology 3 domain (SH3), a central Src homology 2 domain (SH2), and a C-terminal Src homology 3 domain (SH3). Homology analysis revealed that AsE(sev)2B shares 49%-95% identity with E(sev)2B homologs from other species. In this study, the expression pattern and location of AsE(sev)2B during different stages of embryonic development and bacterial challenge were investigated by means of real-time qPCR, Western blotting and immunohistochemistry. Results showed that the highest expression level of AsE(sev)2B was at 0 h. After challenged by Gram-positive bacteria and Gram-negative bacteria, AsE(sev)2B was remarkably upregulated at 106 cellsL-1 bacterial concentrations. These results suggested that AsE(sev)2B plays a vital role during early embryonic development and in immune responses against bacterial challenge.


Assuntos
Artemia/genética , Artemia/imunologia , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Sequência de Bases , Perfilação da Expressão Gênica , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Filogenia , Alinhamento de Sequência
10.
Fish Shellfish Immunol ; 87: 737-743, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30779996

RESUMO

galectin-2 plays important roles in innate and adaptive immunity. In this study, galectin-2 (OnGal-2) was identified from Nile tilapia (Oreochromis niloticus). Its tissue distribution and expression patterns following bacterial infection were also investigated. OnGal-2 is widely distributed in various tissues of healthy tilapia. After Streptococcus agalactiae challenge, OnGal-2 expressions were significantly up-regulated in all tested tissues. Meanwhile, the recombinant OnGal-2 (rOnGal-2) protein showed strong agglutinating activities against both Gram-negative bacteria and Gram-positive bacteria. Moreover, rOnGal-2 could promote phagocytosis of macrophages. Taken together, the present study indicated that OnGal-2 might play roles in the immune responses of Nile tilapia against bacterial pathogens.


Assuntos
Ciclídeos/genética , Ciclídeos/imunologia , Doenças dos Peixes/imunologia , Galectina 2/genética , Galectina 2/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Testes de Aglutinação/veterinária , Animais , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Análise de Sequência de DNA/veterinária , Infecções Estreptocócicas/imunologia , Streptococcus agalactiae/fisiologia
11.
Int J Mol Sci ; 20(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769793

RESUMO

Living organisms display internal biological rhythms, which are an evolutionarily conserved adaptation to the environment that drives their rhythmic behavioral and physiological activities. The gut microbiota has been proposed, in association with diet, to regulate the intestinal peripheral clock. However, the effect of gut dysbiosis on liver remains elusive, despite that germfree mice show alterations in liver metabolic functions and the hepatic daily rhythm. We analyzed whether the disruption of gut microbial populations with various antibiotics would differentially impact liver functions in mice. Our results support the notion of an impact on the hepatic biological rhythm by gram-positive bacteria. In addition, we provide evidence for differential roles of gut microbiota spectra in xenobiotic metabolism that could protect against the harmful pharmacological effects of drugs. Our results underscore a possible link between liver cell proliferation and gram-positive bacteria.


Assuntos
Relógios Circadianos/genética , Disbiose/genética , Microbioma Gastrointestinal/genética , Fígado/fisiologia , Animais , Proliferação de Células/efeitos dos fármacos , Disbiose/tratamento farmacológico , Disbiose/fisiopatologia , Microbioma Gastrointestinal/fisiologia , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/fisiologia , Humanos , Intestinos/microbiologia , Intestinos/fisiologia , Fígado/efeitos dos fármacos , Fígado/microbiologia , Camundongos
12.
Chem Soc Rev ; 48(2): 428-446, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30601473

RESUMO

Bacterial-infections are mostly due to bacteria in an adhering, biofilm-mode of growth and not due to planktonically growing, suspended-bacteria. Biofilm-bacteria are much more recalcitrant to conventional antimicrobials than planktonic-bacteria due to (1) emergence of new properties of biofilm-bacteria that cannot be predicted on the basis of planktonic properties, (2) low penetration and accumulation of antimicrobials in a biofilm, (3) disabling of antimicrobials due to acidic and anaerobic conditions prevailing in a biofilm, and (4) enzymatic modification or inactivation of antimicrobials by biofilm inhabitants. In recent years, new nanotechnology-based antimicrobials have been designed to kill planktonic, antibiotic-resistant bacteria, but additional requirements rather than the mere killing of suspended bacteria must be met to combat biofilm-infections. The requirements and merits of nanotechnology-based antimicrobials for the control of biofilm-infection form the focus of this Tutorial Review.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Portadores de Fármacos/química , Nanotecnologia/métodos , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Farmacorresistência Bacteriana/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Humanos , Nanopartículas/química
13.
Fish Shellfish Immunol ; 87: 193-201, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30639866

RESUMO

The serum complement component C1q mediates a variety of immune regulatory functions. Herein, we identified a globular head C1q (ghC1q) gene in razor clam Sinonovacula constricta. The complete Sc-ghC1q gene was 872 bp long included an 81 bp 5'-untranslated region (UTR), a 95 bp 3'-UTR with a poly(A) tail, and an open reading frame (ORF) of 696 bp. The mRNA expression of Sc-ghC1q was upregulated in hepatopancreas and hemocytes. After Staphylococcus aureus or Vibrio anguillarum challenge, Sc-ghC1q mRNA transcript abundance was significantly upregulated in hemolymph. Recombinant Sc-ghC1q protein could bind lipopolysaccharide (LPS) and lipoteichoic acid (LTA), and it could agglutinate both Gram-positive and Gram-negative bacteria. Additionally, flow cytometry revealed that Sc-ghC1q strongly promoted phagocytosis in hemocytes. Together, these results demonstrated that Sc-ghC1q played an important role in innate immunity in S. constricta.


Assuntos
Complemento C1q/genética , Complemento C1q/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Penaeidae/genética , Penaeidae/imunologia , Testes de Aglutinação , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Complemento C1q/química , Perfilação da Expressão Gênica , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Lipopolissacarídeos/farmacologia , Filogenia , Alinhamento de Sequência , Ácidos Teicoicos/farmacologia
14.
Int Immunopharmacol ; 61: 283-289, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29906743

RESUMO

Lipoteichoic acid (LTA)-induced acute lung injury (ALI) is an experimental model for mimicking Gram-positive bacteria-induced pneumonia that is a refractory disease with lack of effective medicines. Here, we reported that costunolide, a sesquiterpene lactone, ameliorated LTA-induced ALI. Costunolide treatment reduced LTA-induced neutrophil lung infiltration, cytokine and chemokine production (TNF-α, IL-6 and KC), and pulmonary edema. In response to LTA challenge, treatment with costunolide resulted less iNOS expression and produced less inflammatory cytokines in bone marrow derived macrophages (BMDMs). Pretreatment with costunolide also attenuated the LTA-induced the phosphorylation of p38 MAPK and ERK in BMDMs. Furthermore, costunolide treatment reduced the phosphorylation of TAK1 and inhibited the interaction of TAK1 with Tab1. In conclusion, we have demonstrated that costunolide protects against LTA-induced ALI via inhibiting TAK1-mediated MAPK signaling pathway, and our studies suggest that costunolide is a promising agent for treatment of Gram-positive bacteria-mediated pneumonia.


Assuntos
Anti-Inflamatórios/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Bactérias Gram-Positivas/fisiologia , Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Pneumonia Bacteriana/tratamento farmacológico , Edema Pulmonar/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Pulmão/imunologia , Pulmão/patologia , MAP Quinase Quinase Quinases/metabolismo , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Transdução de Sinais , Ácidos Teicoicos
15.
J Photochem Photobiol B ; 183: 318-330, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29754050

RESUMO

The green synthesis of metal nanoparticles using phytochemical from marine seaweeds is a fast-growing research field in nanotechnology. Here, the biosynthesis of zinc oxide nanoparticles was achieved using the hot water extract of Sargassum wightii. The hot water extract prepared from S. wightii (H Sw) and ZnO NPs were studied by UV-visible and FTIR spectroscopy, SEM and XRD. Then, both products were evaluated for antibiofilm activity towards aquatic pathogens. The nanoparticles' immunostimulating potential on green tiger prawns, Penaeus semisulcatus was studied through immersion and dietary administration. Shrimp immune parameters (i.e., total hemocytes count (THC), respiratory bursts (RBs), phenoloxidase (PO) and superoxide dismutase (SOD) activity) were significantly affected by exposure or ingestion of ZnO nanoparticles. In addition, the hot water extract and ZnO nanoparticles had high antibiofilm activity against Gram-positive (B. subtilis, S. aureus) and Gram-negative (S. sonnei, P. aeruginosa) microbial pathogens. It was accomplished that the ZnO nanoparticles can be used as the bacteriostatic and immunostimulant agents through immersion and dietary administration enhancing immunity of green tiger shrimp. Furthermore, the toxicity effects of ZnO nanoparticles were 100% at 24 h on Aedes aegypti 3 rd instar larvae at the concentration of 100 µg/mL and the greatest efficacy was accomplished by H Sw ZnO NPs against the Ae. aegypti after 24 h (LC50 49.22; LC90 86.96 mg/mL), if compared to the seaweed extract alone. Morphological and histological damages triggered by nanoexposure were investigated.


Assuntos
Antibacterianos/química , Imunidade Inata/efeitos dos fármacos , Nanopartículas Metálicas/química , Penaeidae/efeitos dos fármacos , Penaeidae/imunologia , Sargassum/química , Óxido de Zinco/química , Aedes/efeitos dos fármacos , Aedes/crescimento & desenvolvimento , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemócitos/citologia , Hemócitos/efeitos dos fármacos , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Nanopartículas Metálicas/toxicidade , Monofenol Mono-Oxigenase/metabolismo , Explosão Respiratória/efeitos dos fármacos , Sargassum/metabolismo , Superóxido Dismutase
16.
Fish Shellfish Immunol ; 79: 340-350, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29803666

RESUMO

C-type lectin (CTL) is an immune receptor and is received extensive attention of its important roles in immune response and immune escape. Some CTL, such as CTL4, has been well characterized in human and several other mammals, but much less documentation exists about the immunological function of CTL4 in lower vertebrates. In the present study, a C-type lectin domain family 4 member, SsCTL4, which is also high homology with CD209 antigen-like protein, from the teleost fish black rockfish (Sebastes schlegelii) was identified and examined at expression and functional levels. The open reading frame of SsCTL4 is 765 bp, and the deduced amino acid sequence of SsCTL4 shares 78%-84% overall identities with the C-type lectin of several fish species. In silico analysis identified several conserved C-type lectin features, including a carbohydrate-recognition domain and four disulfide bond-forming cysteine residues. Expression of SsCTL4 occurred in multiple tissues and was upregulated during bacterial and viral infection. Recombinant SsCTL4 (rSsCTL4) exhibited apparent binding activities against bacteria (Edwardsiella tarda and Vibrio anguillarum) and virus (infectious spleen and kidney necrosis virus, ISKNV). rSsCTL4 was able to agglutinate the Gram-negative and Gram-positive bacteria in a Ca2+-dependent manner. The agglutinating ability of rSsCTL4 was abolished in the absence of calcium or presence of mannose. rSsCTL4 also increased macrophage bactericidal activity. In the presence of rSsCTL4, fish exhibited enhanced resistance against bacterial infection but increased susceptibility to viral infections. Collectively, these results indicate that SsCTL4 serves as a pattern recognition receptor that not only promotes bactericidal activity, but may also serve as targets for virus manipulation of host defense system.


Assuntos
Doenças dos Peixes/imunologia , Peixes/genética , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Aglutinação , Sequência de Aminoácidos , Animais , Sequência de Bases , Infecções por Vírus de DNA/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/imunologia , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Iridoviridae/fisiologia , Lectinas Tipo C/química , Filogenia , Distribuição Aleatória , Alinhamento de Sequência/veterinária
17.
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
18.
PLoS One ; 13(4): e0194898, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29617411

RESUMO

The emergence of pathogenic multidrug-resistant bacteria demands new approaches in finding effective antibacterial agents. Synthetic flavonoids could be a reliable solution due to their important antimicrobial activity. We report here the potent in vitro antibacterial activity of ClCl-flav-a novel synthetic tricyclic flavonoid. The antimicrobial effects were tested using the minimum inhibitory concentration (MIC), time kill and biofilm formation assays. Fluorescence microscopy and scanning electron microscopy were employed to study the mechanism of action. MTT test was used to assess the cytotoxicity of ClCl-flav. Our results showed that Gram positive bacteria were more sensitive (MIC = 0.24 µg/mL) to ClCl-flav compared to the Gram negative ones (MIC = 3.9 µg/mL). We found that our compound showed significantly enhanced antibacterial activities, 32 to 72-fold more active than other synthetic flavonoids. ClCl-flav showed bactericidal activity at concentrations ranging from 0.48 to 15.62 µg/mL. At twice the MIC, all Escherichia coli and Klebsiella pneumoniae cells were killed within 1 h. Also ClCl-flav presented good anti-biofilm activity. The mechanism of action is related to the impairment of the cell membrane integrity. No or very low cytotoxicity was evidenced at effective concentrations against Vero cells. Based on the strong antibacterial activity and cytotoxicity assessment, ClCl-flav has a good potential for the design of new antimicrobial agents.


Assuntos
Antibacterianos/síntese química , Flavonoides/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cercopithecus aethiops , Flavonoides/síntese química , Flavonoides/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Células Vero
19.
BMC Ophthalmol ; 18(1): 85, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29614999

RESUMO

BACKGROUND: To investigate characteristics of biofilm which is usually found in silicone tube for nasolacrimal duct surgery and can be the root of chronic bacterial infections eventually resulted in surgical failure. METHODS: To form a biofilm, sterile silicone tube was placed in culture media of Staphylococcus aureus, Corynebacterium matruchotii, Pseudomonas aeruginosa, or Streptococcus pneumonia. Biofilms formed on these silicone tubes were fixed with 95% ethanol and stained with 0.1% crystal violet. After staining, the optical densities of biofilms were measured using spectrophotometer on a weekly basis for 12 weeks. RESULTS: Staphylococcus aureus group and Pseudomonas aeruginosa group formed significantly more amounts of biofilms compared to the control group. The maximum optical densities of the two groups were found on week 3-4 followed by a tendency of decrease afterwards. However, the amounts of biofilms formed in other groups of silicone tubes were not statistically significant from that of the control group. CONCLUSIONS: Bacterial species that could form biofilm on silicone tube included Staphylococcus aureus (week 3) and Pseudomonas aeruginosa (Week 4). It is important to first consider that the cause of infection around 1 month after silicone tube intubation can be Staphylococcus aureus and Pseudomonas aeruginosa.


Assuntos
Biofilmes/crescimento & desenvolvimento , Dacriocistorinostomia/instrumentação , Bactérias Gram-Positivas/fisiologia , Pseudomonas/isolamento & purificação , Stents/microbiologia , Análise de Variância , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Ducto Nasolacrimal/cirurgia , Silicones , Especificidade da Espécie
20.
Medicine (Baltimore) ; 97(14): e0150, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29620628

RESUMO

In general, physicians believe that the presence of bacterial engulfment in white blood cells (WBCs) on Gram-stained sputum is a hallmark of lower respiratory infection. However, no studies have described the significance or diagnostic accuracy of engulfment in lower respiratory tract infections.We prospectively studied sputum samples by Gram staining (Favor method) for their quality and engulfment score in WBCs obtained from patients with respiratory symptoms at inpatient and outpatient settings at Kyorin University Hospital between December 2012 and April 2015.A total of 163 patients were enrolled. The patients were classified into an infection (n = 93) or non-infection (n = 70) group based on clinical or radiological findings prior to the evaluation of sputum samples. The proportion of engulfment-positive cases was equal in the infection and non-infection groups (49.5% vs 35.7%, P = 0.11). In the infection group, the engulfment score (%) for Streptococcus pneumoniae was significantly lower (median 3%, interquartile range [IQR]: 2% to 5%, P = 0.005) than that of the non-S. pneumoniae bacteria (H. influenzae, M. catarrhalis, and methicillin-susceptible Staphylococcus aureus (MSSA))(median 22.5%, IQR: 17% to 35.5%). The engulfment score of S. pneumoniae in the WBC was low in the infection group, and no cases were recognized in the non-infection group. Using a cut-off value of 3%, the diagnostic accuracy for infection was as follows: sensitivity: 50%, specificity: 65.7%, and area under the curve (AUC): 0.579 (95% CI 0.464 to 0.694). For the non-S. pneumoniae bacteria (H. influenzae, M. catarrhalis, and MSSA), the engulfment score was significantly higher in the infection group (median 22.5%, IQR 17 to 35.5%) than in the non-infection group (median 6.0%, IQR: 3 to 13%, P = 0.011), and the diagnostic accuracy for infection was as follows: sensitivity: 75%, specificity: 85.7%, and AUC: 0.902 (95% CI 0.75 to 1.00) when the threshold for the engulfment score was defined as 18%.This study provides the first evidence that the engulfment of bacteria in WBCs is not always indicative of infection and that the engulfment score can fluctuate according to the pathogen.


Assuntos
Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Interações Hospedeiro-Patógeno/fisiologia , Leucócitos/microbiologia , Infecções Respiratórias/diagnóstico , Escarro/microbiologia , Idoso , Área Sob a Curva , Feminino , Violeta Genciana , Bactérias Gram-Positivas/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Contagem de Leucócitos , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/fisiologia , Fenazinas , Estudos Prospectivos , Infecções Respiratórias/microbiologia , Sensibilidade e Especificidade , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/fisiologia
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