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1.
Vet Microbiol ; 288: 109923, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38061277

ABSTRACT

Escherichia coli and Salmonella Typhimurium are the main pathogens of diarrhea in weaned piglets. The prevention of bacterial diarrhea in weaned piglets by phage is rarely reported. We conducted this study to evaluate the preventive effect of phages on mixed Escherichia coli and Salmonella Typhimurium infections in weaned piglets. A novel phage named NJ12 was isolated by using Salmonella Typhimurium SM022 as host bacteria and characterized by electron microscopy, genomic analysis and in vitro bacteriostatic activity. Phage NJ12 and a previously reported phage EP01 were microencapsulated with sodium alginate to make phage cocktail. Microencapsulated phage cocktail and PBS (Phosphate buffer solution) were used to piglets the phage and phage-free group through oral administration before bacterial infection 2 h, respectively. Piglets of the phage and phage-free group were consumed with feed contaminated with 6 mL (108CFU/mL) Escherichia coli O157:H7 GN07 (GXEC-N07) and 6 mL (108CFU/mL) SM022 every day for seven consecutive days. The results showed that piglets in the phage-free group had more severe diarrhea, larger decreased average weight gain and higher levels of neutrophils compared with piglets in phage group. Meanwhile, piglets in the phage-free group had higher load of SM022 and GN07 in jejunal tissue and more severe intestinal damage compared with piglets in group phage in vivo. In addition, oral administration phage can significant decreased the relative abundance of Enterobacteriaceae but hardly repaired the changes of diversity and composition of gut microbiota caused by the mixed infection of SM022 and GN07. This implies that phage used as a feed additive have a marvelous preventive effect on bacterial diarrhea during weaning of piglets.


Subject(s)
Bacteriophages , Dysentery , Escherichia coli Infections , Escherichia coli O157 , Salmonella Infections , Swine Diseases , Animals , Swine , Salmonella typhimurium , Escherichia coli O157/genetics , Weaning , Diarrhea/prevention & control , Diarrhea/veterinary , Diarrhea/microbiology , Escherichia coli Infections/prevention & control , Escherichia coli Infections/veterinary , Escherichia coli Infections/microbiology , Dysentery/veterinary , Swine Diseases/prevention & control , Swine Diseases/microbiology
2.
Article in English | MEDLINE | ID: mdl-37668855

ABSTRACT

Salmonellosis is a disease caused by non-typhoid Salmonella, and although some lactic acid bacteria strains have been shown previously to relieve Salmonellosis symptoms, little has been studied about the preventive mechanism of Lentilactobacillus buchneri (L. buchneri) against Salmonella infection in vivo. Therefore, the L. buchneri was fed to C57BL/6 mice for 10 days to build a protective system of mice to study its prevention and possible mechanisms. The results showed that L. buchneri GX0328-6 alleviated symptoms caused by Salmonella typhimurium infection among C57BL/6 mice, including low survival rate, weight loss, increase in immune organ index and hepatosplenomegaly, and modulated serum immunoglobulin levels and intrinsic immunity. Importantly, the L. buchneri GX0328-6 enhanced the mucosal barrier of the mouse jejunum by upregulating the expression of tight junction proteins such as ZO-1, occludins, and claudins-4 and improved absorptive capacity by increasing the length of mouse jejunal villus and the ratio of villus length to crypt depth and decreasing the crypt depth. L. buchneri GX0328-6 reduced the intestinal proliferation and invasion of Salmonella typhimurium by modulating the expression of antimicrobial peptides in the intestinal tract of mice, and reduced intestinal inflammation and systemic spread in mice by downregulating the expression of IL-6 and promoting the expression of IL-10. Furthermore, L. buchneri GX0328-6 increased the relative abundance of beneficial bacteria colonies and decreased the relative abundance of harmful bacteria in the cecum microflora by modulating the microflora in the cecum contents.

3.
BMC Vet Res ; 19(1): 165, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37730566

ABSTRACT

BACKGROUND: Escherichia coli (E. coli) is a common pathogen that often causes diarrhea in piglets. Since bacteria are becoming more and more resistant to antibiotics, phages have become a promising alternative therapy. However, the therapy of oral phage often fails to achieve the desired effect. A novel phage named A221 was isolated by using E. coli GXXW-1103 as host strain, characterized by electron microscopy, genomic sequencing and analyzed by measuring lysis ability in vitro. RESULTS: Phage A221 was identified as a member of Ackermannviridae, Aglimvirinae, Agtrevirus with 153297 bp genome and effectively inhibited bacterial growth in vitro for 16 h. This study was conducted to evaluate the therapeutic effect of oral microencapsulated phage A221 on E. coli GXXW-1103 infections in weaned piglets. The protective effect of phage was evaluated by body weight analysis, bacterial load and histopathological changes. The results showed that with the treatment of phage A221, the body weight of piglets increased, the percentage of Enterobacteriaceae in duodenum decreased to 0.64%, the lesions in cecum and duodenum were alleviated, and the bacterial load in the jejunal lymph nodes, cecum and spleen were also significantly different with infected group (P < 0.001). CONCLUSIONS: The results showed that phage A221 significantly increased the daily weight gain of piglets, reduced the bacterial load of tissues and the intestinal lesions, achieved the same therapeutic effect as antibiotic Florfenicol. Taken together, oral microencapsulated phage A221 has a good therapeutic effect on bacterial diarrhea of weaned piglets, which provides guidance for the clinical application of phage therapy in the future.


Subject(s)
Bacteriophages , Escherichia coli Infections , Phage Therapy , Swine Diseases , Animals , Swine , Escherichia coli , Phage Therapy/veterinary , Escherichia coli Infections/therapy , Escherichia coli Infections/veterinary , Diarrhea/therapy , Diarrhea/veterinary , Anti-Bacterial Agents/therapeutic use , Body Weight , Swine Diseases/therapy
4.
Front Immunol ; 14: 1195382, 2023.
Article in English | MEDLINE | ID: mdl-37465686

ABSTRACT

Lactobacillus plantarum has recently been found to be a natural source feed additive bacteria with great advantages in food safety and animal welfare. Discovering novel strains with commercial application potentiation could benefit the local poultry industry, and in particular support Chinese farmers. In this study, we tested a recently isolated novel strain of Lactobacillus plantarum GX17 as a feed additive on the growth performance and intestinal barrier functions of 1-day-old Chinese yellow-feather chicks. As good as other commercial probiotics, feeding with Lactobacillus plantarum GX17 showed significant improvements in humoral immune responses and enhanced the immune effect after vaccination for either the Newcastle disease vaccine or the avian influenza vaccine. This study also found that feeding with Lactobacillus plantarum GX17 improved the feed-to-weight ratio and caused a significant increase of the villus length to crypt depth ratio. Furthermore, Lactobacillus plantarum GX17 significantly up-regulated the mRNA expression of CLDN, MUC2, and TLR2, all of which are jejunum-associated barrier genes, indicating an improvement of the intestinal barrier functions by enhancing the tight junction between epithelia cells. These results are comparable to the effects of feeding the commercial complex probiotics that improve the expression levels of CLDN, ocludin, MUC2, TLR2, and TLR4. In terms of maintaining intestinal health, commercial complex probiotics increased the relative abundance of Parabacteroides and Romboutsia, while Lactobacillus plantarum GX17 increased the relative abundance of Pseudoflavonifractor. Our data suggest that Lactobacillus plantarum GX17 could enhance the intestinal absorption of nutrients and therefore improve the growth performance of Chinese yellow-feather chicks. In conclusion, compared with the commercial complex probiotics, Lactobacillus plantarum GX17 has more positive effects on the growth performance and intestinal barrier function of yellow-feather chickens, and can be used as a feed additive.


Subject(s)
Gastrointestinal Microbiome , Lactobacillus plantarum , Animals , Lactobacillus plantarum/physiology , Chickens/microbiology , Feathers , Toll-Like Receptor 2
5.
Virus Genes ; 59(4): 613-623, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37170002

ABSTRACT

As the problem of bacterial resistance becomes serious day by day, bacteriophage as a potential antibiotic substitute attracts more and more researchers' interest. In this study, Escherichia phage Kayfunavirus CY1 was isolated from sewage samples of swine farms and identified by biological characteristics and genomic analysis. One-step growth curve showed that the latent period of phage CY1 was about 10 min, the outbreak period was about 40 min and the burst size was 35 PFU/cell. Analysis of the electron microscopy and whole-genome sequence showed that the phage should be classified as a member of the Autographiviridae family, Studiervirinae subfamily. Genomic analysis of phage CY1 (GenBank accession no. OM937123) revealed a genome size of 39,173 bp with an average GC content of 50.51% and 46 coding domain sequences (CDSs). Eight CDSs encoding proteins involved in the replication and regulation of phage DNA, 2 CDSs encoded lysis proteins, 14 CDSs encoded packing and morphogenesis proteins. Genomic and proteomic analysis identified no sequence that encoded for virulence factor, integration-related proteins or antibiotic resistance genes. In summary, morphological and genomics suggest that phage CY1 is more likely a novel Escherichia phage.


Subject(s)
Bacteriophages , Caudovirales , Swine , Animals , Proteomics , Genome, Viral/genetics , Genomics , Bacteriophages/genetics , Caudovirales/genetics , Escherichia/genetics
6.
Microbiol Spectr ; 11(3): e0070123, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37140381

ABSTRACT

The interferon (IFN) system is an extremely powerful antiviral response in animal cells. The subsequent effects caused by porcine astrovirus type 1 (PAstV1) IFN activation are important for the host's response to viral infections. Here, we show that this virus, which causes mild diarrhea, growth retardation, and damage of the villi of the small intestinal mucosa in piglets, induces an IFN response upon infection of PK-15 cells. Although IFN-ß mRNA was detected within infected cells, this response usually occurs during the middle stages of infection, after genome replication has taken place. Treatment of PAstV1-infected cells with the interferon regulatory factor 3 (IRF3) inhibitor BX795 decreased IFN-ß expression, whereas the nuclear factor kappa light chain enhancer of activated B cells (NF-κB) inhibitor BAY11-7082 did not. These findings indicate that PAstV induced the production of IFN-ß via IRF3-mediated rather than NF-κB-mediated signaling pathways in PK-15 cells. Moreover, PAstV1 increased the protein expression levels of retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5) in PK-15 cells. The knockdown of RIG-I and MDA5 decreased the expression levels of IFN-ß and the viral loads and increased the infectivity of PAstV1. In conclusion, PAstV1 induced the production of IFN-ß via the RIG-I and MDA5 signaling pathways, and the IFN-ß produced during PAstV1 infection inhibited viral replication. These results will help provide new evidence that PAstV1-induced IFNs may protect against PAstV replication and pathogenesis. IMPORTANCE Astroviruses (AstVs) are widespread and can infect multiple species. Porcine astroviruses produce mainly gastroenteritis and neurological diseases in pigs. However, astrovirus-host interactions are less well studied, particularly with respect to their antagonism of IFN. Here, we report that PAstV1 acts via IRF3 transcription pathway activation of IFN-ß. In addition, the knockdown of RIG-I and MDA5 attenuated the production of IFN-ß induced by PAstV1 in PK-15 cells and increased efficient viral replication in vitro. We believe that these findings will help us to better understand the mechanism of how AstVs affect the host IFN response.


Subject(s)
NF-kappa B , Signal Transduction , Animals , Swine , Interferon-Induced Helicase, IFIH1/metabolism , NF-kappa B/metabolism , Interferons
7.
Virus Genes ; 59(2): 302-311, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36701048

ABSTRACT

Escherichia coli is a common conditional pathogen, for which antibiotic therapy is considered an effective treatment. The imprudent use of antibiotics has led to the increase of multiple-antibiotic-resistant E. coli species. With the incidence of antibiotic resistance reaching a crisis point, it is imperative to find alternative treatments for multidrug-resistant infections. Using phage for pathogen control is a promising treatment option to combat bacterial resistance. In this study, a novel virulent Podoviridae phage Kayfunavirus TM1 infecting Escherichia coli was isolated from pig farm sewage in Guangxi, China. The one-step growth curve with the optimal multiplicity of infection of 0.01 revealed a latent period of 10 min and a burst size of 50 plaque-forming units per cell. The stability test reveals that it is stable from 4 to 60 °C and pH from 3 to 11. The double-stranded DNA genome of phage Kayfunavirus TM1 is composed of 39,948 base pairs with a GC content of 50.03%.


Subject(s)
Bacteriophages , Swine , Animals , Bacteriophages/genetics , Escherichia coli/genetics , Genome, Viral , DNA, Viral/genetics , China , Anti-Bacterial Agents
8.
Viruses ; 14(12)2022 11 27.
Article in English | MEDLINE | ID: mdl-36560651

ABSTRACT

Food contamination by Salmonella can lead to serious foodborne diseases that constantly threaten public health. Innovative and effective strategies are needed to control foodborne pathogenic contamination since the incidence of foodborne diseases has increased gradually. In the present study, two broad-spectrum phages named Salmonella phage PSE-D1 and Salmonella phage PST-H1 were isolated from sewage in China. Phages PSE-D1 and PST-H1 were obtained by enrichment with Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) CVCC1806 and Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) CVCC3384, respectively. They were able to lyse Salmonella, E. coli and K. pneumoniae and exhibited broad host range. Further study demonstrated that PSE-D1 and PST-H1 showed high pH and thermal tolerances. Phage PSE-D1 belongs to the Jiaodavirus genus, Tevenvirinae subfamily, while phage PST-H1 belongs to the Jerseyvirus genus, Guernseyvirinae subfamily according to morphology and phylogeny. The results of genome analysis showed that PSE-D1 and PST-H1 lack virulence and drug-resistance genes. The effects of PSE-D1 and PST-H1 on controlling S. Enteritidis CVCC1806 and S. Typhimurium CVCC3384 contamination in three kinds of foods (eggshells, sausages and milk) were further investigated, respectively. Our results showed that, compared to phage-free groups, PSE-D1 and PST-H1 inhibited the growth of their host strain significantly. A significant reduction of host bacteria titers (1.5 and 1.9 log10 CFU/sample, p < 0.001) on eggshells was observed under PSE-D1 and PST-H1 treatments, respectively. Furthermore, administration of PSE-D1 and PST-H1 decreased the counts of bacteria by 1.1 and 1.2 log10 CFU/cm2 (p < 0.001) in sausages as well as 1.5 and 1.8 log10 CFU/mL (p < 0.001) in milk, respectively. Interesting, the bacteriostasis efficacy of both phages exhibited more significantly at 4 °C than that at 28 °C in eggshells and milk and sausages. In sum, the purpose of our research was evaluating the counteracting effect of phage PSE-D1 and PST-H1 on the spread of Salmonella on contaminated foods products. Our results suggested that these two phage-based biocontrol treatments are promising strategies for controlling pathogenic Salmonella contaminated food.


Subject(s)
Foodborne Diseases , Salmonella Phages , Humans , Escherichia coli , Food Microbiology , Salmonella enteritidis , Salmonella typhimurium
9.
Vet Sci ; 9(12)2022 Dec 05.
Article in English | MEDLINE | ID: mdl-36548836

ABSTRACT

Escherichia coli (O78) is an avian pathogenic Escherichia coli (APEC). It can cause perihepatitis, pericarditis, septicemia and even systemic infections in the poultry industry. With the incidence of antibiotic resistance reaching a crisis point, it is important to find alternative treatments for multidrug-resistant infections. The use of phages to control pathogens is a promising therapeutic option for antibiotic replacement. In this study, we isolated a lytic phage called vB_EcoS_GN06 from sewage. It lysed APEC GXEC-N22. Transmission electron microscopy showed that the phage belongs to family Siphoviridae. Phage GN06 has a 107,237 bp linear double-stranded DNA genome with 39.2% GC content and 155 coding sequences. It belongs to the genus Tequintavirus, subfamily Markadamsvirinae. The multiplicity of infection of 0.01 and the one-step growth showed that the latent time is 60 min and the burst size is 434 PFU/cell. Temperature and pH stability tests showed that phage GN06 was stable in the range of 4 °C-60 °C and pH 5-9. GN06 showed significant inhibition of APEC both within the liquid medium and in biofilm formation. These results suggest that phage GN06 has the potential to control bacterial pathogens. Thus, GN06 has the potential to be a new potential candidate for phage therapy.

10.
BMC Microbiol ; 22(1): 311, 2022 12 20.
Article in English | MEDLINE | ID: mdl-36539715

ABSTRACT

BACKGROUND: Cattle industry is critical for China's livestock industry, whereas E. coli infection and relevant diseases could lead huge economic loss. Traditional mammalian models would be costly, time consuming and complicated to study pathological changes of bovine E. coli. There is an urgent need for a simple but efficient animal model to quantitatively evaluate the pathological changes of bovine-derived E. coli in vivo. Caenorhabditis elegans (C. elegans) has a broad host range of diverse E. coli strains with advantages, including a short life cycle, a simple structure, a transparent body which is easily visualized, a well-studied genetic map, an intrinsic immune system which is conservable with more complicated mammalians. RESULTS: Here, we considered that O126 was the dominant serotype, and a total of 19 virulence factors were identified from 41 common E. coli virulence factors. Different E. coli strains with diverse pathogenicity strengths were tested in C. elegans in E. coli with higher pathogenicity (EC3/10), Nsy-1, Sek-1 and Pmk-1 of the p38 MAPK signaling pathway cascade and the expression of the antimicrobial peptides Abf-3 and Clec-60 were significantly up-regulated comparing with other groups. E. coli with lower pathogenicity (EC5/13) only activated the expression of Nsy-1 and Sek-1 genes in the p38 MAPK signaling pathway, Additionally, both groups of E. coli strains caused significant upregulation of the antimicrobial peptide Spp-1. CONCLUSION: Thirteen E. coli strains showed diverse pathogenicity in nematodes and the detection rate of virulence factors did not corresponding to the virulence in nematodes, indicating complex pathogenicity mechanisms. We approved that C. elegans is a fast and convenient detection model for pathogenic bacteria virulence examinations.


Subject(s)
Caenorhabditis elegans Proteins , Escherichia coli Infections , Cattle , Animals , Caenorhabditis elegans/microbiology , Escherichia coli/genetics , Escherichia coli/metabolism , Caenorhabditis elegans Proteins/genetics , Escherichia coli Infections/veterinary , Escherichia coli Infections/microbiology , Virulence Factors/genetics , Virulence Factors/metabolism , p38 Mitogen-Activated Protein Kinases/genetics , Mammals/metabolism
11.
Mitochondrial DNA B Resour ; 7(7): 1288-1290, 2022.
Article in English | MEDLINE | ID: mdl-35844973

ABSTRACT

The complete mitogenome sequence of Coilia brachygnathus (Kreyenberg & Pappenheim, 1908) from Wabu Lake in Huai River Basin was annotated and characterized in this study. This mitochondrial genome is a circular DNA molecule of 16.896 bp in size with 57.52% AT content, including 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and an AT-rich region (control region) as other bony fishes. There are a total of 10 overlap locations and 15 intergenic spacer regions throughout the mitogenome of C. brachygnathus. All PCGs employed a standard ATG as a start codon, except cytochrome c oxidase 1 (cox1) with GTG. In addition, TAA or TAG was identified as the typical stop codon. A phylogenetic tree reconstructed with the maximum likelihood method depicted a clone relationship with eight species of genus Coilia and our previous study based on the amino acid sequences of 13 mitochondrial PCGs. The complete mitochondrial genome is a valuable resource in classifying and conserving C. brachygnathus.

12.
Virus Genes ; 58(5): 448-457, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35716226

ABSTRACT

Escherichia coli, a gram-negative bacterium, was generally considered conditional pathogenic bacteria and the proportion of bacteria resistant to commonly used specified antibacterial drugs exceeded 50%. Phage therapeutic application has been revitalized since antibiotic resistance in bacteria was increasing. Compared with antibiotics, phage is the virus specific to bacterial hosts. However, further understanding of phage-host interactions is required. In this study, a novel phage specific to a E. coli strain, named as phage Kayfunavirus ZH4, was isolated and characterized. Transmission electron microscopy showed that phage ZH4 belongs to the family Autographiviridae. The whole-genome analysis showed that the length of phage ZH4 genome was 39,496 bp with 49 coding domain sequence (CDS) and no tRNA was detected. Comparative genome and phylogenetic analysis demonstrated that phage ZH4 was highly similar to phages belonging to the genus Kayfunavirus. Moreover, the highest average nucleotide identity (ANI) values of phage ZH4 with all the known phages was 0.86, suggesting that ZH4 was a relatively novel phage. Temperature and pH stability tests showed that phage ZH4 was stable from 4° to 50 °C and pH range from 3 to 11. Host range of phage ZH4 showed that there were only 2 out of 17 strains lysed by phage ZH4. Taken together, phage ZH4 was considered as a novel phage with the potential for applications in the food and pharmaceutical industries.


Subject(s)
Bacteriophages , Caudovirales , Anti-Bacterial Agents , Bacteriophages/genetics , Caudovirales/genetics , Coliphages/genetics , Escherichia coli/genetics , Genome, Viral , Nucleotides , Phylogeny
13.
Addict Behav ; 132: 107341, 2022 09.
Article in English | MEDLINE | ID: mdl-35584984

ABSTRACT

BACKGROUND AND OBJECTIVE: Metacognitive monitoring refers to the process in which an individual analyzes their own mental state, then monitors and adjusts cognitive activities to achieve a predetermined goal. Recent research has suggested a strong link between metacognition and drug cravings. Conversely, few studies on the impact of metacognitive monitoring on methamphetamine (MA) cravings exist. Thus, this study investigated whether drug cravings would impair MA abusers' metacognitive monitoring and explored the prediction effects of drug cravings. METHOD: Seventy MA abusers from the Zhejiang Compulsory Isolation Drug Rehabilitation Center and 65 non-users from the Wenzhou Medical University were recruited for this experimental study. The judgment of learning (JOL) paradigm was used to examine metacognitive monitoring, and cue-induced pictures were used to induce MA abusers' drug cravings. Analysis of covariance (ANCOVA), partial correlation, and regression analysis were performed. RESULTS: Compared with non-users, MA abusers had significantly poorer metacognitive monitoring and tended to overestimate their performance. Furthermore, there was a significant correlation between the accuracy of JOLs and drug cravings, which indicated that metacognitive monitoring was weakened by drug cravings with higher cravings imposing more severe impacts. In addition, the regression analysis suggested that drug cravings can predict metacognitive monitoring.


Subject(s)
Metacognition , Methamphetamine , Craving , Humans , Judgment , Learning
14.
Glob Health Action ; 15(1): 2015743, 2022 12 31.
Article in English | MEDLINE | ID: mdl-35114900

ABSTRACT

BACKGROUND: Community health workers (CHWs) are individuals who are trained and equipped to provide essential health services to their neighbors and have increased access to healthcare in communities worldwide for more than a century. However, the World Health Organization (WHO) Guideline on Health Policy and System Support to Optimize Community Health Worker Programmes reveals important gaps in the evidentiary certainty about which health system design practices lead to quality care. Routine data collection across countries represents an important, yet often untapped, opportunity for exploratory data analysis and comparative implementation science. However, epidemiological indicators must be harmonized and data pooled to better leverage and learn from routine data collection. METHODS: This article describes a data harmonization and pooling Collaborative led by the organizations of the Community Health Impact Coalition, a network of health practitioners delivering community-based healthcare in dozens of countries across four WHO regions. OBJECTIVES: The goals of the Collaborative project are to; (i) enable new opportunities for cross-site learning; (ii) use positive and negative outlier analysis to identify, test, and (if helpful) propagate design practices that lead to quality care; and (iii) create a multi-country 'brain trust' to reinforce data and health information systems across sites. RESULTS: This article outlines the rationale and methods used to establish a data harmonization and pooling Collaborative, early findings, lessons learned, and directions for future research.


Subject(s)
Community Health Workers , Public Health , Community Health Services , Delivery of Health Care , Health Services , Humans
15.
Viruses ; 14(2)2022 01 29.
Article in English | MEDLINE | ID: mdl-35215879

ABSTRACT

Salmonella and Escherichia coli (E. coli) food contamination could lead to serious foodborne diseases. The gradual increase in the incidence of foodborne disease invokes new and efficient methods to limit food pathogenic microorganism contamination. In this study, a polyvalent broad-spectrum Escherichia phage named Tequatrovirus EP01 was isolated from pig farm sewage. It could lyse both Salmonella Enteritidis (S. Enteritidis) and E. coli and exhibited broad host range. EP01 possessed a short latent period (10 min), a large burst size (80 PFU/cell), and moderate pH stability (4-10) and appropriate thermal tolerance (30-80 °C). Electron microscopy and genome sequence revealed that EP01 belonged to T4-like viruses genus, Myoviridae family. EP01 harbored 12 CDSs associated with receptor-binding proteins and lacked virulence genes and drug resistance genes. We tested the inhibitory effect of EP01 on S. Enteritidis, E. coli O157:H7, E. coli O114:K90 (B90), and E. coli O142:K86 (B) in liquid broth medium (LB). EP01 could significantly reduce the counts of all tested strains compared with phage-free groups. We further examined the effectiveness of EP01 in controlling bacterial contamination in two kinds of foods (meat and milk) contaminated with S. Enteritidis, E. coli O157:H7, E. coli O114:K90 (B90), and E. coli O142:K86 (B), respectively. EP01 significantly reduced the viable counts of all the tested bacteria (2.18-6.55 log10 CFU/sample, p < 0.05). A significant reduction of 6.55 log10 CFU/cm2 (p < 0.001) in bacterial counts on the surface of meat was observed with EP01 treatment. Addition of EP01 at MOI of 1 decreased the counts of bacteria by 4.3 log10 CFU/mL (p < 0.001) in milk. Generally, the inhibitory effect exhibited more stable at 4 °C than that at 28 °C, whereas the opposite results were observed in milk. The antibacterial effects were better at MOI of 1 than that at MOI of 0.001. These results suggests that phage EP01-based method is a promising strategy of controlling Salmonella and Escherichia coli pathogens to limit microbial food contamination.


Subject(s)
Escherichia coli/virology , Food Contamination/prevention & control , Myoviridae/physiology , Salmonella enteritidis/virology , Animals , Bacteriolysis , Escherichia coli/growth & development , Food Microbiology , Genome, Viral , Host Specificity , Meat/microbiology , Milk/microbiology , Myoviridae/classification , Myoviridae/genetics , Myoviridae/isolation & purification , Phylogeny , Salmonella enteritidis/growth & development , Sewage/virology , Swine
16.
Vet Microbiol ; 266: 109332, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35033842

ABSTRACT

Phage therapy is a promising alternative antibiotic strategy to combat multidrug-resistant bacteria infections. Most studies focus on the synergistic effects, while the antagonistic interactions between phage and antibiotics is rarely studied. Here, we isolated and identified a novel polyvalent phage SaP7, which is capable of infecting multidrug-resistant Salmonella S7 and several E. coli strains. Morphology via electron microscopy showed that SaP7 belonged to the Myoviridae family. Genomic analysis revealed that the genome of SaP7 lacked any genes associated with antibiotic resistance, toxins, lysogeny, and virulence factors. We discovered the antagonism efficacy of SaP7 combined amoxicillin/potassium clavulanate (AMC) in counteracting Salmonella S7 in piglet-models by bacterial loads in feces and tissues. The consistent result as above between SaP7 and amoxicillin (AMX) was further verified in BALB/c mice-models. Furthermore, in vitro, plaque assay and minimum inhibitory concentration (MIC) determinations showed that AMX or AMC or cefepime (FEP) inhibited SaP7 plaque formation respectively and SaP7 decreased bacterial susceptibility of Salmonella S7 to AMX, AMC and FEP. And the negative interference of SaP7 with the bacteriostasis to Salmonella S7 of these three ß-lactam antibiotics was observed in planktonic cultures via microtiter plates, but could not prevent the bacteriostasis of high titer of phage or high concentration of antibiotics. Finally, our research suggested that a polyvalent phage SaP7 existed antagonism with several ß-lactam antibiotics. It is therefore crucial to fully and cautiously evaluate phage/antibiotic interactions and probable outcomes to avoid antagonistic impacts and failure of antibiotic and phage combination therapy.


Subject(s)
Bacteriophages , Phage Therapy , Animals , Anti-Bacterial Agents/pharmacology , Bacteriophages/genetics , Escherichia coli , Mice , Phage Therapy/veterinary , Swine , beta-Lactams/pharmacology
17.
Dalton Trans ; 45(44): 17748-17758, 2016 Nov 28.
Article in English | MEDLINE | ID: mdl-27766332

ABSTRACT

Highly crystalline and idiomorphic CoTiO3 single crystals with a well-defined polyhedral morphology were grown successfully for the first time by a facile flux method. Herein, the effects of the molten salt type and cobalt precursor on the phase composition, crystallization habit and morphology of the CoTiO3 products were also investigated. Importantly, using the flux-grown CoTiO3 crystal as the visible-light sensitizer due to its narrow band gap to couple with graphitic carbon nitride (g-C3N4) by a direct in situ thermal induced polycondensation route, novel CoTiO3/g-C3N4 composite photocatalysts were obtained. The as-synthesized samples were systematically characterized by XRD, EDS, SEM, TEM, SAED, HRTEM, FT-IR, XPS, DRS and PL techniques. The results revealed that CoTiO3 polyhedral crystals were closely combined with g-C3N4 nanosheets leading to the formation of a heterojunction structure at the interface between CoTiO3 and g-C3N4. Photocatalytic evaluation showed that the heterostructured CoTiO3/g-C3N4 composite exhibited much higher photocatalytic activity for the degradation of methyl orange under visible light irradiation than that of individual CoTiO3 and g-C3N4, which could be mainly ascribed to the synergistic effect between CoTiO3 and g-C3N4, including the enhanced visible-light harvesting ability and more efficient separation and longer lifetime of photogenerated charge carriers. Furthermore, the composite photocatalyst showed an excellent stability and reusability during four successive cycles. Finally, a possible mechanism responsible for the charge separation and improved photocatalytic activity was proposed.

18.
J Dermatol ; 42(3): 296-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25639454

ABSTRACT

This study was designed to investigate the relationship between plasma lipid profile and acne. Acne patients (n = 181) and healthy volunteers (n = 130) matched in terms of both age and sex were enrolled. Plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C) and lipoprotein (LP)(a) levels were measured. TC, LDL-C and LP(a) levels in male and female patients with severe acne were significantly higher than in the healthy control group (P < 0.05). TG in male patients with severe and moderate acne was significantly higher than in the healthy control group (P < 0.05). LP(a) in male and female patients with mild, moderate and severe acne was significantly higher than in the healthy control group (P < 0.05). The constituent ratio of male and female patients with TC, TG, LDL-C and LP(a) over the normal range was significantly higher than in the healthy control group. In this study, acne patients were frequently associated with abnormal lipid profile, providing a new basis for further exploration of the pathogenesis, as well as new treatments, of acne vulgaris.


Subject(s)
Acne Vulgaris/blood , Lipids/blood , Adolescent , Adult , Case-Control Studies , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Female , Humans , Lipoprotein(a)/blood , Male , Severity of Illness Index , Sex Factors , Triglycerides/blood , Young Adult
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(1): 99- following 102, 2014 Jan.
Article in Chinese | MEDLINE | ID: mdl-24461191

ABSTRACT

Steroid-resistant nephrotic syndrome poses a significant clinical challenge. Its pathogenesis has not been fully elucidated. In recent years, numerous studies have shown that podocyte-specific gene mutations may play important roles in the development of steroid-resistant nephrotic syndrome. Among the identified genes mutated in podocytes include NPHS2, NPHS1, WT1, TRPC6, MDR1, PLCE1, LMX1B, and LAMB2. This review aims to summarize the characteristics of these mutated genes in podocytes. The putative role for these podocyte-specific mutated genes in the pathogenesis, diagnosis, treatment and prognosis of steroid-resistant nephrotic syndrome is also discussed.


Subject(s)
Mutation , Nephrotic Syndrome/congenital , Podocytes/metabolism , ATP Binding Cassette Transporter, Subfamily B , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Genes, Wilms Tumor , Humans , Intracellular Signaling Peptides and Proteins/genetics , LIM-Homeodomain Proteins/genetics , Membrane Proteins/genetics , Nephrotic Syndrome/genetics , TRPC Cation Channels/genetics , TRPC6 Cation Channel , Transcription Factors/genetics
20.
Wei Sheng Yan Jiu ; 42(2): 302-5, 2013 Mar.
Article in Chinese | MEDLINE | ID: mdl-23654112

ABSTRACT

OBJECTIVE: To establish a TLC-FTIR method for detection of western medicine phenolphthalein added illegally into anti-obesity and healthcare food. METHODS: The sample was extracted with anhydrous alcohol. The stationary phase was the GF254 aluminium alloy silica gel plates (10 cm x 20 cm) while the developing solvent was acetic ether: petroleum ether (60-90): methanol = 10: 6: 1. The sample volume was 2 microl. After primary screening by the UV lamp 254nm and self-made 2% NaOH test paper, the preparative technique of TLC was used to separate the component. Then the component was detected by FTIR and compared with the FTIR spectrogram of standard substance. RESULTS: Five of the ten samples contained phenolphthalein with the same testing results by using the TLC scanning and HPLC. CONCLUSION: The established method is accurate and reliable and can be used for detection of phenolphthalein illegally added into the products.


Subject(s)
Dietary Supplements/analysis , Food Contamination/analysis , Obesity/prevention & control , Phenolphthalein/analysis , Chromatography, Thin Layer/methods , Dietary Supplements/adverse effects , Humans , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared/methods
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