scholarly journals Isolation and characterization of bacteriaophages against virulent Aeromonas hydrophila

2020 ◽  
Author(s):  
Jin Liu ◽  
Shanshan Gao ◽  
Yuhao Dong ◽  
Chengping Lu ◽  
Yongjie Liu
Keyword(s):  
Aeromonas Hydrophila ◽  
Bacterial Infections ◽  
Economic Loss ◽  
Mice Model ◽  
Bacterial Killing ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Potential Alternative ◽  
Virulent Aeromonas Hydrophila ◽  
Drug Resistant Strains

Abstract Background: Aeromonas hydrophila is an important water-borne pathogen that leads to a great economic loss in aquaculture. Along with the abuse of antibiotics, drug-resistant strains rise rapidly. In addition, the biofilms formed by this bacterium limited the antibacterial effect of antibiotics. Bacteriophages have been attracting increasing attention as a potential alternative to antibiotics against bacterial infections. Results: Five phages against pathogenic A. hydrophila, named N21, W3, G65, Y71 and Y81, were isolated. Morphological analysis by transmission electron microscopy revealed that phages N21, W3 and G65 belong to the family Myoviridae, while Y71 and Y81 belong to the Podoviridae. These phages were found to have broad host spectra, short latent periods and normal burst sizes. They were sensitive to high temperature but had a wide adaptability to the pH. In addition, the phages G65 and Y81 showed considerable bacterial killing effect and potential in preventing formation of A. hydrophila biofilm; and the phages G65, W3 and N21 were able to scavenge mature biofilm effectively. Phage treatments applied to the pathogenic A. hydrophila in mice model resulted in a significantly decreased bacterial loads in tissues. Conclusions: Five A. hydrophila phages were isolated with broad host ranges, low latent periods, and wide pH and thermal tolerance. And the phages exhibited varying abilities in controlling A. hydrophila infection. This work presents promising data supporting the future use of phage therapy.

scholarly journals Isolation and characterization of bacteriophages against virulent Aeromonas hydrophila

2020 ◽  
Author(s):  
Jin Liu ◽  
Shanshan Gao ◽  
Yuhao Dong ◽  
Chengping Lu ◽  
Yongjie Liu
Keyword(s):  
Aeromonas Hydrophila ◽  
Bacterial Infections ◽  
Economic Loss ◽  
Mice Model ◽  
Bacterial Killing ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Potential Alternative ◽  
Virulent Aeromonas Hydrophila ◽  
Drug Resistant Strains

Abstract Background: Aeromonas hydrophila is an important water-borne pathogen that leads to a great economic loss in aquaculture. Along with the abuse of antibiotics, drug-resistant strains rise rapidly. In addition, the biofilms formed by this bacterium limited the antibacterial effect of antibiotics. Bacteriophages have been attracting increasing attention as a potential alternative to antibiotics against bacterial infections. Results: Five phages against pathogenic A. hydrophila, named N21, W3, G65, Y71 and Y81, were isolated. Morphological analysis by transmission electron microscopy revealed that phages N21, W3 and G65 belong to the family Myoviridae, while Y71 and Y81 belong to the Podoviridae. These phages were found to have broad host spectra, short latent periods and normal burst sizes. They were sensitive to high temperature but had a wide adaptability to the pH. In addition, the phages G65 and Y81 showed considerable bacterial killing effect and potential in preventing formation of A. hydrophila biofilm; and the phages G65, W3 and N21 were able to scavenge mature biofilm effectively. Phage treatments applied to the pathogenic A. hydrophila in mice model resulted in a significantly decreased bacterial loads in tissues. Conclusions: Five A. hydrophila phages were isolated with broad host ranges, low latent periods, and wide pH and thermal tolerance. And the phages exhibited varying abilities in controlling A. hydrophila infection. This work presents promising data supporting the future use of phage therapy.

scholarly journals Isolation and characterization of bacteriaophages against virulent Aeromonas hydrophila

2020 ◽  
Author(s):  
Jin Liu ◽  
Shanshan Gao ◽  
Yuhao Dong ◽  
Chengping Lu ◽  
Yongjie Liu
Keyword(s):  
Aeromonas Hydrophila ◽  
Bacterial Infections ◽  
Economic Loss ◽  
Considerable Effect ◽  
Mice Model ◽  
Biofilm Inhibition ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Virulent Aeromonas Hydrophila ◽  
Drug Resistant Strains

Abstract Background: Aeromonas hydrophila is an important water-borne pathogen that leads to a great economic loss in aquaculture. Along with the abuse of antibiotics, drug-resistant strains rise rapidly. In addition, the biofilms formed by this bacterium limited the antibacterial effect of antibiotics. Bacteriaophages have been attracted increasing attention as a potential alternative to antibiotics against bacterial infections. Results: Five phages against pathogenic A. hydrophila, named N21, W3, G65, Y71 and Y81, were isolated. Morphological analysis by transmission electron microscopy revealed that phages N21, W3 and G65 belong to the family Myoviridae, while Y71 and Y81 belong to the Podoviridae. These phages were found to have broad host spectra, although their burst sizes were varied per infected host cell at their optimal multiplicity of infection. They were sensitive to high temperature but had a wide adaptability to the pH. In addition, the phages G65 and Y81 showed considerable effect on growth and biofilm inhibition of A. hydrophila; and the phages G65, W3 and N21 were able to scavenge mature biofilm effectively. Phage treatments applied to the pathogenic A. hydrophila in mice model resulted in a significantly decreased bacterial loads in tissues. Conclusions: Five A. hydrophila phages were isolated with broad host ranges, low latent periods, and wide pH and thermal tolerance. And the phages exhibited varying abilities in controlling A. hydrophila infection. This work presents promising data supporting the future use of phage therapy.

Silver Oxide–Copper Oxide Nanocomposite Preparation and Antimicrobial Activity as a Source for the Treatment of Fish Diseases

2017 ◽  
pp. 140-151
Author(s):  
Sayed Reza Shaffiey ◽  
Sayedeh Fatemeh Shaffiey
Keyword(s):  
Aeromonas Hydrophila ◽  
Bacterial Infections ◽  
Antimicrobial Activities ◽  
Cuo Nanoparticles ◽  
Negative Bacterium ◽  
Electron Micrograph ◽  
X Ray Diffraction ◽  
Gram Negative ◽  
Transmission Electron ◽  
Scanning Electron

Aeromonas hydrophila is a heterotrophic, gram negative bacterium which is primary or secondary cause of ulcers, fin rot, tail rot, and hemorrhagic septicaemia in fish. The treatments for this infection are only restricted to some antibiotics. So, novel materials are being searched for combating with bacterial infections and the resulting consequences. In this chapter, Ag2O/CuO nanocomposites were synthesized chemically and characterized by X-ray diffraction (XRD), scanning electron micrograph (SEM) and transmission electron microscope (TEM). The antimicrobial activities of Ag2O/CuO nanoparticles (NPs), was checked by both well diffusion and turbidometric (spectrophotometric) method. Synthesized nanoparticles exhibited their antimicrobial efficacy in both the standard inhibitory assays; these results thus provide a scope for further research on the application of Ag2O/CuO nanoparticles as disinfectant and/or antibiotic in the fishery industry.

scholarly journals Isolation and characterization of bacteriophages against virulent Aeromonas hydrophila

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Jin Liu ◽  
Shanshan Gao ◽  
Yuhao Dong ◽  
Chengping Lu ◽  
Yongjie Liu
Keyword(s):  
Aeromonas Hydrophila ◽  
Isolation And Characterization ◽  
Virulent Aeromonas Hydrophila

scholarly journals Zinc-doped Prussian blue enhances photothermal clearance of Staphylococcus aureus and promotes tissue repair in infected wounds

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jun Li ◽  
Xiangmei Liu ◽  
Lei Tan ◽  
Zhenduo Cui ◽  
Xianjin Yang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Prussian Blue ◽  
Metabolic Pathways ◽  
Bacterial Infections ◽  
Wound Repair ◽  
Local Heat ◽  
Photothermal Effect ◽  
Bacterial Killing ◽  
Potential Alternative

Abstract The application of photothermal therapy to treat bacterial infections remains a challenge, as the high temperatures required for bacterial elimination can damage healthy tissues. Here, we develop an exogenous antibacterial agent consisting of zinc-doped Prussian blue (ZnPB) that kills methicillin-resistant Staphylococcus aureus in vitro and in a rat model of cutaneous wound infection. Local heat triggered by the photothermal effect accelerates the release and penetration of ions into the bacteria, resulting in alteration of intracellular metabolic pathways and bacterial killing without systemic toxicity. ZnPB treatment leads to the upregulation of genes involved in tissue remodeling, promotes collagen deposition and enhances wound repair. The efficient photothermal conversion of ZnPB allows the use of relatively few doses and low laser flux, making the platform a potential alternative to current antibiotic therapies against bacterial wound infections.

The size of extracellular vesicles secreted by different types of stem cells

2018 ◽  
pp. 38-42
Author(s):  
И.Б. Алчинова ◽  
М.В. Полякова ◽  
И.Н. Сабурина ◽  
М.Ю. Карганов
Keyword(s):  
Stem Cells ◽  
Extracellular Vesicles ◽  
Culture Media ◽  
Living Organism ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Study Results ◽  
Multipotent Mesenchymal Stem Cells ◽  
Rat Adipose Tissue ◽  
Almost All

Механизм терапевтического действия мультипотентных мезенхимных стволовых клеток (ММСК) на облученный организм в последнее время вызывает повышенный интерес исследователей. В качестве активного участника паракринного механизма реализации этого эффекта предлагают рассматривать внеклеточные везикулы, секретируемые практически всеми клетками живого организма. Цель работы: выделить и охарактеризовать внеклеточные везикулы, продуцируемые стволовыми клетками различной природы. Материалы и методы. Суспензии внеклеточных везикул, выделенных по модифицированному протоколу дифференциального центрифугирования из культуральных жидкостей от культур ММСК костного мозга человека 2-го пассажа и ММСК жировой ткани крысы 4-го пассажа, были проанализированы методом просвечивающей электронной микроскопии и методом анализа траекторий наночастиц. Результаты. Исследование показало наличие в обоих образцах микрочастиц размерами до и около 100 нм, однако процентное содержание частиц разных размеров в суспензии различалось для двух анализируемых типов клеток. Заключение. Полученные результаты могут свидетельствовать о специфике секреции, обусловленной клеточным типом. A mechanism of the therapeutic effect of multipotent mesenchymal stem cells (MMSC) on irradiated body has recently arisen much interest of researchers. Extracellular vesicles (EVs) secreted by almost all cells of a living organism were suggested to actively contribute to the paracrine mechanism of this effect. The aim of the study was isolation and characterization of extracellular vesicles produced by various types of stem cells. Materials and methods. Suspensions of EVs were isolated from culture media of passage 2 human bone marrow-derived MMSC and passage 4 rat adipose tissue-derived MMSC using a modified protocol of differential centrifugation and then studied using transmission electron microscopy and nanoparticle tracking analysis. Results. The study showed the presence of microparticles with a size of >100 nm in the examined samples. However, the percent content of particles with different sizes in the suspension was different in two analyzed types of cell culture. Conclusion. The study results might reflect a specificity of secretion determined by the cell type.

scholarly journals Novel Carbon Dots Derived from Glycyrrhizae Radix et Rhizoma and Their Anti-Gastric Ulcer Effect

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1512
Author(s):  
Yuhan Liu ◽  
Meiling Zhang ◽  
Jinjun Cheng ◽  
Yue Zhang ◽  
Hui Kong ◽  
...  
Keyword(s):  
Gastric Ulcer ◽  
Photoelectron Spectroscopy ◽  
Carbon Dots ◽  
High Performance ◽  
Raw264.7 Cells ◽  
Mice Model ◽  
X Ray ◽  
Glycyrrhizae Radix ◽  
Transmission Electron ◽  
High Resolution Tem

Glycyrrhizae Radix et Rhizoma (GRR) is one of the commonly used traditional Chinese medicines in clinical practice, which has been applied to treat digestive system diseases for hundreds of years. GRR is preferred for anti-gastric ulcer, however, the main active compounds are still unknown. In this study, GRR was used as precursor to synthesize carbon dots (CDs) by a environment-friendly one-step pyrolysis process. GRR-CDs were characterized by using transmission electron microscopy, high-resolution TEM, fourier transform infrared, ultraviolet-visible and fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. In addition, cellular toxicity of GRR-CDs was studied by using CCK-8 in RAW264.7 cells, and the anti-gastric ulcer activity was evaluated and confirmed using mice model of acute alcoholic gastric ulcer. The experiment confirmed that GRR-CDs were the spherical structure with a large number of active groups on the surface and their particle size ranged from 2 to 10 nm. GRR-CDs had no toxicity to RAW264.7 cells at concentration of 19.5 to 5000 μg/mL and could reduce the oxidative damage of gastric mucosa and tissues caused by alcohol, as demonstrated by restoring expression of malondialdehyde, superoxide dismutase and nitric oxide in serum and tissue of mice. The results indicated the explicit anti-ulcer activity of GRR-CDs, which provided a new insights for the research on effective material basis of GRR.

scholarly journals AMPK activates Parkin independent autophagy and improves post sepsis immune defense against secondary bacterial lung infections

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nathaniel B. Bone ◽  
Eugene J. Becker ◽  
Maroof Husain ◽  
Shaoning Jiang ◽  
Anna A. Zmijewska ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Inflammatory Responses ◽  
Abdominal Sepsis ◽  
Immune Defense ◽  
Bacterial Killing ◽  
Lung Infections ◽  
Sepsis Survivors ◽  
The Impact

AbstractMetabolic and bioenergetic plasticity of immune cells is essential for optimal responses to bacterial infections. AMPK and Parkin ubiquitin ligase are known to regulate mitochondrial quality control mitophagy that prevents unwanted inflammatory responses. However, it is not known if this evolutionarily conserved mechanism has been coopted by the host immune defense to eradicate bacterial pathogens and influence post-sepsis immunosuppression. Parkin, AMPK levels, and the effects of AMPK activators were investigated in human leukocytes from sepsis survivors as well as wild type and Park2−/− murine macrophages. In vivo, the impact of AMPK and Parkin was determined in mice subjected to polymicrobial intra-abdominal sepsis and secondary lung bacterial infections. Mice were treated with metformin during established immunosuppression. We showed that bacteria and mitochondria share mechanisms of autophagic killing/clearance triggered by sentinel events that involve depolarization of mitochondria and recruitment of Parkin in macrophages. Parkin-deficient mice/macrophages fail to form phagolysosomes and kill bacteria. This impairment of host defense is seen in the context of sepsis-induced immunosuppression with decreased levels of Parkin. AMPK activators, including metformin, stimulate Parkin-independent autophagy and bacterial killing in leukocytes from post-shock patients and in lungs of sepsis-immunosuppressed mice. Our results support a dual role of Parkin and AMPK in the clearance of dysfunctional mitochondria and killing of pathogenic bacteria, and explain the immunosuppressive phenotype associated Parkin and AMPK deficiency. AMPK activation appeared to be a crucial therapeutic target for the macrophage immunosuppressive phenotype and to reduce severity of secondary bacterial lung infections and respiratory failure.

scholarly journals Isolation and characterization of pathogenic Escherichia coli bacteriophages from chicken and beef offal

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Celosia Lukman ◽  
Christopher Yonathan ◽  
Stella Magdalena ◽  
Diana Elizabeth Waturangi
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
High Efficiency ◽  
Multiplicity Of Infection ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Pathogenic Escherichia Coli ◽  
Family Based

Abstract Objective This study was conducted to isolate and characterize lytic bacteriophages for pathogenic Escherichia coli from chicken and beef offal, and analyze their capability as biocontrol for several foodborne pathogens. Methods done in this research are bacteriophage isolation, purification, titer determination, application, determination of host range and minimum multiplicity of infection (miMOI), and bacteriophage morphology. Results Six bacteriophages successfully isolated from chicken and beef offal using EPEC and EHEC as host strain. Bacteriophage titers observed between 109 and 1010 PFU mL−1. CS EPEC and BL EHEC bacteriophage showed high efficiency in reduction of EPEC or EHEC contamination in meat about 99.20% and 99.04%. The lowest miMOI was 0.01 showed by CS EPEC bacteriophage. CI EPEC and BL EPEC bacteriophage suspected as Myoviridae family based on its micrograph from Transmission Electron Microscopy (TEM). Refers to their activity, bacteriophages isolated in this study have a great potential to be used as biocontrol against several foodborne pathogens.

Sign in / Sign up

Export Citation Format

Share Document