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1.
BMC Public Health ; 24(1): 389, 2024 02 06.
Article in English | MEDLINE | ID: mdl-38321421

ABSTRACT

BACKGROUND: Improving people with disabilities' participation in sports and cultural activities benefits their physical and mental health. However, only a few studies have examined the factors that influence participation systematically. METHODS: Using the survey data gathered from 4,319 disabled people living in a district in Wuhan, China, this study explored the impacts of sports and cultural activity participation in terms of individual physiological characteristics, socioeconomic factors, and built environmental features. The sports and cultural facility supply and the walkability index of their community environment were calculated to assess built environment features. Binary logistic regression models were also used to investigate the influence of the aforementioned variables. RESULTS: There is a significant positive correlation between sports and cultural activity participation and education (OR = 3.44, p < 0.01), employment status (OR = 2.04, p < 0.01), as well as the number of cultural facilities (OR = 1.33, p < 0.01) in the neighborhood area. No significant association was found between the inclination to participate frequently and individual psychological factors. CONCLUSION: Regarding people with disabilities' participation in sports and cultural activities, socioeconomic and built environment factors are more influential than individual psychological ones. The findings can give ideas for identifying targeted and comprehensive interventions to promote a healthy lifestyle for people with disabilities.


Subject(s)
Disabled Persons , Sports , Humans , Sports/psychology , Disabled Persons/psychology , Social Environment , Environment , Surveys and Questionnaires
2.
ACS Appl Mater Interfaces ; 16(7): 8346-8364, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38323561

ABSTRACT

Vaccines are widely regarded as one of the most effective weapons in the fight against infectious diseases. Currently, vaccines must be stored and transported at low temperatures as high temperatures can lead to a loss of vaccine conformation and reduced therapeutic efficacy. Metal-organic frameworks (MOFs), such as zeolitic imidazole framework-8 (ZIF-8), are a new class of hybrid materials with large specific surface areas, high loading rates, and good biocompatibility and are successful systems for vaccine delivery and protection. Silk fibroin (SF) has a good biocompatibility and thermal stability. In this study, the hepatitis B surface antigen (HBsAg) was successfully encapsulated in ZIF-8 to form HBsAg@ZIF-8 (HZ) using a one-step shake and one-pot shake method. Subsequently, the SF coating modifies HZ through hydrophobic interactions to form HBsAg/SF@ZIF-8 (HSZ), which enhanced the thermal stability and immunogenicity of HBsAg. Compared to free HBsAg, HZ and HSZ improved the thermostability of HBsAg, promoted the antigen uptake and lysosomal escape, stimulated dendritic cell maturation and cytokine secretion, formed an antigen reservoir to promote antibody production, and activated CD4+ T and CD8+ T cells to enhance memory T-cell production. Importantly, HSZ induced a strong immune response even after 14 days of storage at 25 °C. Furthermore, the nanoparticles prepared by the one-step shake method exhibited superior properties compared to those prepared by the one-pot shake method. This study highlights the importance of SF-coated ZIF-8, which holds promise for investigating thermostable vaccines and breaking the vaccine cold chain.


Subject(s)
Fibroins , Metal-Organic Frameworks , Hepatitis B Surface Antigens , Fibroins/pharmacology , Metal-Organic Frameworks/pharmacology , CD8-Positive T-Lymphocytes , Hepatitis B Vaccines/therapeutic use , Immunity, Cellular
3.
J Mater Chem B ; 11(40): 9712-9720, 2023 10 18.
Article in English | MEDLINE | ID: mdl-37791404

ABSTRACT

The development of organic dyes with emission peaks in the second near-infrared window (NIR-II 1000-1700 nm) is highly desirable for in vivo imaging and imaging-guided phototheranostics. However, the lack of appropriate molecular frameworks and the challenges associated with complex synthesis critically hinder the development of new candidate fluorophores. J-Aggregation is considered as a smart and straightforward way to construct such a therapeutic agent with NIR-II fluorescence imaging properties. Here, we present the design and synthesis of an aza-BODIPY probe (TA). Upon encapsulation within the amphiphilic polymer DSPEG-PEG2000-NH2, TA underwent self-assembly and formed J-aggregates (TAJ NPs), which showed emission at 1020 nm. High spatial resolution and adequate signal-to-noise ratio of the TAJ NPs are demonstrated for noninvasive bioimaging of the vasculature, lymph nodes and bones of mice in the NIR-II region. Moreover, the TAJ NPs exhibited good tumor enrichment efficiency with reduced liver accumulation and significant imaging-guided phototherapy performance against lung cancer cells. Taken together, this work not only introduces a new NIR-II imaging and phototheranostic agent based on J-aggregates, but also provides insight into the development of versatile organic dyes for future clinical implementation.


Subject(s)
Nanoparticles , Neoplasms , Animals , Mice , Nanoparticles/chemistry , Neoplasms/therapy , Boron Compounds , Fluorescent Dyes/chemistry
4.
Influenza Other Respir Viruses ; 17(3): e13114, 2023 03.
Article in English | MEDLINE | ID: mdl-36909299

ABSTRACT

The surface-enhanced Raman scattering (SERS) has recently drawn attention in the detection of respiratory viruses, but there have been few reports of the direct detection of viruses. In this study, a sandwich immunomagnetic bead SERS was established for the rapid diagnosis of the H5N1 influenza virus. The detection limit was estimated to be 5.0 × 10-6 TCID50/ml. The method showed excellent specificity with no cross-reaction with H1N1, H5N6 or H9N2. The H5N1 influenza virus detection accuracy of the SERS method was 100% in chicken embryos. The results hold great promise for the utilization of SERS as an innovative approach in the diagnosis of influenza virus.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza A Virus, H5N1 Subtype , Influenza A Virus, H9N2 Subtype , Influenza in Birds , Influenza, Human , Animals , Chick Embryo , Humans , Chickens
5.
PLoS Negl Trop Dis ; 16(12): e0011017, 2022 12.
Article in English | MEDLINE | ID: mdl-36542659

ABSTRACT

BACKGROUND: Ticks act as important vectors of infectious agents, and several emerging tick-borne viruses have recently been identified to be associated with human diseases in northeastern China. However, little is known about the tick virome in northeastern China. METHODS: Ticks collected from April 2020 to July 2021 were pooled for metagenomic analysis to investigate the virome diversity in northeastern China. RESULTS: In total, 22 RNA viruses were identified, including four each in the Nairoviridae and Phenuiviridae families, three each in the Flaviviridae, Rhabdoviridae, and Solemoviridae families, two in the Chuviridae family, and one each in the Partitiviridae, Tombusviridae families and an unclassified virus. Of these, eight viruses were of novel species, belonging to the Nairoviridae (Ji'an nairovirus and Yichun nairovirus), Phenuiviridae (Mudanjiang phlebovirus), Rhabdoviridae (Tahe rhabdovirus 1-3), Chuviridae (Yichun mivirus), and Tombusviridae (Yichun tombus-like virus) families, and five members were established human pathogens, including Alongshan virus, tick-borne encephalitis virus, Songling virus, Beiji nairovirus, and Nuomin virus. I. persulcatus ticks had significant higher number of viral species than H. japonica, H. concinna, and D. silvarum ticks. Significant differences in tick viromes were observed among Daxing'an, Xiaoxing'an and Changbai mountains. CONCLUSIONS: These findings showed an extensive diversity of RNA viruses in ticks in northeastern China, revealing potential public health threats from the emerging tick-borne viruses. Further studies are needed to explain the natural circulation and pathogenicity of these viruses.


Subject(s)
RNA Viruses , Rhabdoviridae , Ticks , Viruses , Animals , Humans , Metagenomics , RNA Viruses/genetics , Viruses/genetics , China , Phylogeny
6.
J Neuroimmunol ; 360: 577722, 2021 11 15.
Article in English | MEDLINE | ID: mdl-34583093

ABSTRACT

The present study aims to develop a bioluminescence Cronobacter muytjensii (C. muytjensii) infection animal model for use to evaluate the spatiotemporal acetylation and cytokine levels of brain. Frist, we cultured a luciferase expressing C. muytjensii that could be used for real-time monitoring in BALB/c mice. Then we performed a comparative acetylation analysis and cytokine levels analysis of the host's brain tissue. Further bioinformatic analysis studies have revealed that that some key acetylation proteins and inflammatory mediators involve in C. muytjensii infection. In this paper, the integration of bioluminescence imaging with Liquid Chromatography and Mass Spectrometry (LC-MS) based proteomics and quantitative analysis cytokine levels provide a systems-level understanding of infected brain response caused by C. muytjensii.


Subject(s)
Brain Chemistry , Cronobacter , Cytokines/metabolism , Enterobacteriaceae Infections/metabolism , Inflammation Mediators/metabolism , Nerve Tissue Proteins/metabolism , Protein Processing, Post-Translational , Whole Body Imaging/methods , Acetylation , Animals , Chromatography, Liquid , Computer Systems , Enterobacteriaceae Infections/drug therapy , Genes, Reporter , Intravital Microscopy , Luciferases , Luminescent Measurements , Mice , Mice, Inbred BALB C , Proteomics , Random Allocation , Tandem Mass Spectrometry , Tigecycline/therapeutic use
7.
Virulence ; 12(1): 2149-2161, 2021 12.
Article in English | MEDLINE | ID: mdl-34369293

ABSTRACT

Drug-resistant pathogenic Staphylococcus aureus (S. aureus) has severely threatened human health and arouses widespread concern. Sortase A (SrtA) is an essential virulence factor of S. aureus, which is responsible for the covalent anchoring of a variety of virulence-related proteins to the cell wall. SrtA has always been regarded as an ideal pharmacological target against S. aureus infections. In this research, we have determined that orientin, a natural compound isolated from various medicinal plants, can effectively inhibit the activity of SrtA with an IC50 of 50.44 ± 0.51 µM. We further demonstrated that orientin inhibited the binding of S. aureus to fibrinogen and diminished biofilm formation and the attaching of Staphylococcal protein A (SpA) to the cell wall in vitro. Using the fluorescence quenching assay, we demonstrated a direct interaction between orientin and SrtA. Further mechanistic studies revealed that the residues Glu-105, Thr-93, and Cys-184 were the key sites for the binding of SrtA to orientin. Importantly, we demonstrated that treatment with orientin attenuated S. aureus virulence of in vivo and protected mice against S. aureus-induced lethal pneumonia. These findings indicate that orientin is a potential drug to counter S. aureus infections and limit the development of drug resistance.


Subject(s)
Aminoacyltransferases/antagonists & inhibitors , Bacterial Proteins/antagonists & inhibitors , Flavonoids/pharmacology , Glucosides/pharmacology , Pneumonia, Bacterial , Staphylococcal Infections , Aminoacyltransferases/genetics , Animals , Cysteine Endopeptidases , Methicillin-Resistant Staphylococcus aureus , Mice , Pneumonia, Bacterial/prevention & control , Staphylococcal Infections/prevention & control
8.
Front Microbiol ; 12: 686864, 2021.
Article in English | MEDLINE | ID: mdl-34295320

ABSTRACT

The evolution and spread of methicillin-resistant Staphylococcus aureus (MRSA) poses a significant hidden risk to human public health. The majority of antibiotics used clinically have become mostly ineffective, and so the development of novel anti-infection strategies is urgently required. Since Staphylococcus aureus (S. aureus) cysteine transpeptidase sortase A (SrtA) mediates the surface-anchoring of proteins to its surface, compounds that inhibit SrtA are considered potential antivirulence treatments. Herein, we report on the efficacy of the potent SrtA inhibitor taxifolin (Tax), a flavonoid compound isolated from Chinese herbs. It was able to reversibly block the activity of SrtA with an IC50 of 24.53 ± 0.42 µM. Tax did not display toxicity toward mammalian cells or S. aureus at a concentration of 200 µM. In addition, Tax attenuated the virulence-related phenotype of SrtA in vitro by decreasing the adherence of S. aureus, reducing the formation of a biofilm, and anchoring of S. aureus protein A on its cell wall. The mechanism of the SrtA-Tax interaction was determined using a localized surface plasmon resonance assay. Subsequent mechanistic studies confirmed that Asp-170 and Gln-172 were the principal sites on SrtA with which it binds to Tax. Importantly, in vivo experiments demonstrated that Tax protects mice against pneumonia induced by lethal doses of MRSA, significantly improving their survival rate and reducing the number of viable S. aureus in the lung tissue. The present study indicates that Tax is a useful pioneer compound for the development of novel agents against S. aureus infections.

9.
Front Microbiol ; 12: 635710, 2021.
Article in English | MEDLINE | ID: mdl-33679670

ABSTRACT

New anti-infective approaches are urgently needed to control multidrug-resistant (MDR) pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA). Sortase A (SrtA) is a membrane-bound cysteine transpeptidase that plays an essential role in the catalysis of covalent anchoring of surface proteins to the cell wall of Staphylococcus aureus (S. aureus). The present study reports identification of a flavonoid, eriodictyol, as a reversible inhibitor of SrtA with an IC50 of 2.229 ± 0.014 µg/mL that can be used as an innovative means to counter both resistance and virulence. The data indicated that eriodictyol inhibited the adhesion of the bacteria to fibrinogen and reduced the formation of biofilms and anchoring of staphylococcal protein A (SpA) on the cell wall. The results of fluorescence quenching experiments demonstrated a strong interaction between eriodictyol and SrtA. Subsequent mechanistic studies revealed that eriodictyol binds to SrtA by interacting with R197 amino acid residue. Importantly, eriodictyol reduced the adhesion-dependent invasion of A549 cells by S. aureus and showed a good therapeutic effect in a model of mouse pneumonia induced by S. aureus. Overall, the results indicated that eriodictyol can attenuate MRSA virulence and prevent the development of resistance by inhibiting SrtA, suggesting that eriodictyol may be a promising lead compound for the control of MRSA infections.

10.
Anal Biochem ; 564-565: 47-53, 2019 01 01.
Article in English | MEDLINE | ID: mdl-30336124

ABSTRACT

Complement factor 5a is a potent proinflammatory mediator that contributes to the pathogenesis of numerous inflammatory diseases. Protein-based C5a inhibitors have proven to be clinically valuable. Aptamers, which are oligonucleic acid chains or polypeptides, can bind to target molecules and hence have the potential to be used for detection and blockade of targets. Here, we describe the discovery that the single-stranded DNA aptamer S1 can bind specifically to swine C5a, which can then be quickly selected for with capillary electrophoresis for high-throughput sequencing. Aptamer S1 bound specifically to swine C5a with a dissociation constant of 4 µM as measured by surface plasmon resonance (SPR). Moreover, aptamer S1 inhibited C5a-induced chemotaxis of neutrophils in vitro. Our study suggests that the S1 aptamer has great potential to be a key structure in the development of effective therapeutic agents against inflammatory diseases.


Subject(s)
Aptamers, Nucleotide/chemistry , Complement C5a/chemistry , Electrophoresis, Capillary/methods , Animals , Swine
11.
Mol Imaging Biol ; 20(1): 21-26, 2018 02.
Article in English | MEDLINE | ID: mdl-28791565

ABSTRACT

PURPOSE: The present study aims to develop five Gram-negative bacteria expressing bacterial luciferase for use to evaluate the influence of different antibiotics on bacterial bioluminescence. PROCEDURES: The pBBR-lux plasmid was introduced into five Gram-negative bacteria; the bioluminescent signals and colony-forming unit (CFU)/ml of all the bioluminescent strains were monitored with six antibiotics at various concentrations. RESULTS: Dose-dependent bioluminescence signals can be used for rapid bacterial antibiotic susceptibility test (AST). All five bioluminescent bacterial strains have similar bioluminescence and CFU enhancement at sub-minimum inhibitory concentration (MIC) of six different antibiotics. CONCLUSION: The bioluminescent signals and CFU enhancement at sub-MIC antibiotic concentrations should be of value in the research of new antibiotic drugs and bioluminescent imaging.


Subject(s)
Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Luminescent Measurements , Plasmids/metabolism , Animals , Bacterial Load/drug effects , Escherichia coli/drug effects , Female , Imaging, Three-Dimensional , Mice, Inbred BALB C , Microbial Sensitivity Tests , Organ Specificity/drug effects , Tigecycline/pharmacology
12.
Anal Chem ; 89(18): 9836-9842, 2017 09 19.
Article in English | MEDLINE | ID: mdl-28803475

ABSTRACT

The characteristic of an ideal bacteria-detection method should have high sensitivity and specificity, be easy to operate, and not have a time-consuming culture process. In this study, we report a new bacteria-detection strategy that can recognize bacteria quickly and directly by surface-enhanced Raman scattering (SERS) with the formation of well-defined bacteria-aptamer@AgNPs. SERS signals generated by bacteria-aptamer@AgNPs exhibited a linear dependence on bacteria (R2 = 0.9671) concentration ranging from 101 to 107 cfu/mL. The detection limit is sensitive down to 1.5 cfu/mL. Meanwhile, the bacteria SERS signal was dramatically enhanced by its specifically recognized aptamer, and the bacteria could be identified directly and visually through the SERS spectrum. This strategy eliminates the puzzling data analysis of previous studies and offers significant advantages over existing approaches, getting a critical step toward the creation of SERS-based biochips for rapid in situ bacteria detection in mixture samples.


Subject(s)
Aptamers, Nucleotide/chemistry , Escherichia coli/isolation & purification , Listeria monocytogenes/isolation & purification , Shigella flexneri/isolation & purification , Staphylococcus aureus/isolation & purification , Metal Nanoparticles/chemistry , Silver/chemistry , Spectrum Analysis, Raman , Surface Properties
13.
Mol Imaging Biol ; 18(4): 519-26, 2016 08.
Article in English | MEDLINE | ID: mdl-26846129

ABSTRACT

PURPOSE: The goal of this study was to develop a plasmid-based lux bio-reporter for use to obtain in vivo images of Brucella suis vaccine strain 2 (B.suis S2) infection with high resolution and good definition. PROCEDURES: The pBBR-lux (pBBR1MCS-2-lxCDABE) plasmid that carries the luxCDABE operon was introduced into B. suis S2 by electroporation yielding B. suis S2-lux. The spatial and temporal transit of B. suis S2 in mice and guinea pigs was monitored by bioluminescence imaging. RESULTS: The plasmid pBBR-lux is stable in vivo and does not appear to impact the virulence or growth of bacteria. This sensitive luciferase reporter could represent B. suis S2 survival in real time. B. suis S2 mainly colonized the lungs, liver, spleen, and uterus in mice and guinea pigs as demonstrated by bioluminescence imaging. CONCLUSION: The plasmid-based lux bioreporter strategy can be used to obtain high resolution in vivo images of B. suis S2 infection in mice and guinea pigs.


Subject(s)
Brucella Vaccine/immunology , Brucella suis/growth & development , Brucella suis/immunology , Brucellosis/immunology , Brucellosis/microbiology , Animals , Bacterial Load , Colony Count, Microbial , Female , Guinea Pigs , Imaging, Three-Dimensional , Luciferases/metabolism , Luminescent Measurements , Mice, Inbred BALB C , Organ Specificity , Peritoneum/microbiology , Peritoneum/pathology
14.
J Food Prot ; 78(5): 1007-12, 2015 May.
Article in English | MEDLINE | ID: mdl-25951398

ABSTRACT

Cronobacter sakazakii is an emerging pathogen that causes severe and life-threatening conditions including meningitis, bacteremia, and necrotizing enterocolitis. An animal model study for extrapolation of C. sakazakii infection can provide a better understanding of pathogenesis. However, methods for real-time monitoring of the course of C. sakazakii infection in living animals have been lacking. We developed a bioluminescent C. sakazakii strain (ATCC 29544) that can be used for real-time monitoring of C. sakazakii infection in BALB/c mice. C. sakazakii ATCC 29544 mainly colonized brain, liver, spleen, kidney, and gastrointestinal tract, as indicated by bioluminescence imaging. This work provides a novel approach for studying the progression of C. sakazakii infection and evaluating therapeutics in a living mouse model.


Subject(s)
Cronobacter sakazakii/isolation & purification , Disease Models, Animal , Enterobacteriaceae Infections/diagnosis , Luminescent Measurements/methods , Animals , Mice , Mice, Inbred BALB C
15.
Vaccine ; 26(10): 1314-21, 2008 Mar 04.
Article in English | MEDLINE | ID: mdl-18262313

ABSTRACT

Several recombinant vaccines expressing the rabies virus glycoprotein have been developed, particularly for the oral vaccination of wildlife. While these vaccines induce protective immunity in some animal species such as foxes, they are less effective in others. Pseudorabies virus (PRV) has been licensed for use as a live vaccine in pigs and possesses an excellent safety and efficacy record. We have used it to construct a recombinant virus, rPRV/eGFP/rgp, expressing the rabies virus glycoprotein. This recombinant virus has been shown to be safe for dogs by oral and intramuscular routes of inoculation and was demonstrated to induce immune responses against both pseudorabies and rabies in dogs after a single oral dose of 2 x 10(7.0) plaque forming units (PFU). Neutralizing antibody titers against rabies reached > 0.5 IU/ml and 1:64-1:128 against pseudorabies by 5 weeks post-vaccination in all dogs, indicating that the pseudorabies virus vector infected dogs and replicated in vivo, and that the rabies virus glycoprotein had been expressed and an effective immune response elicited. Antibody titers were maintained for over 6 months. This suggests that pseudorabies virus could be an effective live vector for recombinant rabies oral vaccination.


Subject(s)
Dog Diseases/immunology , Dog Diseases/prevention & control , Herpesvirus 1, Suid/immunology , Pseudorabies Vaccines/adverse effects , Pseudorabies Vaccines/immunology , Pseudorabies/immunology , Pseudorabies/prevention & control , Animals , Antibodies, Viral/analysis , Antibodies, Viral/biosynthesis , Blotting, Southern , Blotting, Western , Cell Line , Chlorocebus aethiops , DNA, Viral/genetics , DNA, Viral/immunology , Dogs , Flow Cytometry , Glycoproteins/biosynthesis , Glycoproteins/genetics , Glycoproteins/immunology , Herpesvirus 1, Suid/genetics , Neutralization Tests , Pseudorabies Vaccines/genetics , Rabies virus/immunology , Vaccination , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Vero Cells
16.
FEMS Yeast Res ; 8(1): 6-9, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18031531

ABSTRACT

The GAL1 and GAL10 genes of Saccharomyces cerevisiae are transcribed divergently and transcription of both genes can be induced by galactose and repressed by glucose. This study describes the construction and characterization of 8 bidirectional expression vectors. These vectors carry both a modified inducible GAL promoter in one direction and a constitutive GPD promoter in the reverse direction. When the gene-encoded alpha-galactosidase was cloned into the modified GAL1 and GAL10 vectors, promoter activity was 85% of wild-type for the GAL1 promoter and 90% of wild-type for the GAL10 promoter, respectively. The modified GAL promoters and GPD promoter did not interfere with one another in the bidirectional vectors. Furthermore, yeast overexpressing human Bax under the control of either modified GAL1 or modified GAL10 in a bidirectional vector conferred a lethal phenotype that was rescued by coexpression of human Bcl-2 under the control of the GPD promoter in the same vector. These eight vectors can be used to express lethal genes and screen for genes that rescue the yeast from the lethal gene product.


Subject(s)
Genes, Fungal , Genetic Vectors , Promoter Regions, Genetic , Recombinant Fusion Proteins/metabolism , Saccharomyces cerevisiae/genetics , Cloning, Molecular , Galactose/pharmacology , Genes, Regulator , Genes, bcl-2/genetics , Glucose/pharmacology , Humans , Recombinant Fusion Proteins/biosynthesis
17.
Am J Vet Res ; 68(8): 812-5, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17669019

ABSTRACT

OBJECTIVE: To investigate the development of enrofloxacin resistance among Escherichia coli isolates obtained from chickens by determining mutant-prevention concentrations (MPCs) and sequence the quinolone resistance-determining regions (QRDRs) of gyrA and parC genes in selected isolates. SAMPLE POPULATION: 15 chicken-derived E coli isolates. PROCEDURES: For all isolates, MPC and minimal inhibition concentration (MIC) of enrofloxacin were determined. The MPCs and maximum serum drug concentrations attained with enrofloxacin doses recommended for treatment of E coli infections in chickens were compared. Mutation frequencies and QRDR sequence changes in gyrA and parC were also determined. RESULTS: In 2 of 15 E coli strains, MPCs were low (0.016 and 0.062 microg/mL), MPC:MIC ratios were 2 and 4, and the GyrA and ParC proteins had no mutations. In 9 susceptible isolates with a GyrA point mutation, MPCs ranged from 2 to 16 microg/mL. For isolates with double mutations in GyrA and a single mutation in ParC, MPCs were > 32 microg/mL (several fold greater than the maximal plasma concentration of enrofloxacin in chickens); mutation frequencies were also much lower, compared with frequencies for single-mutation isolates. CONCLUSIONS AND CLINICAL RELEVANCE: For E coli infections of chickens, MPC appears to be useful for determining enrofloxacin-dosing strategies. The high MPC:MIC ratio may result in enrofloxacin-treatment failure in chickens infected with some wild-type gyrA E coli isolates despite the isolates' enrofloxacin susceptibility (MICs 0.125 to 1 microg/mL). For infections involving isolates with high MPCs, especially those containing mutations in gyrA and parC genes, treatment with combinations of antimicrobials should be adopted.


Subject(s)
Anti-Bacterial Agents/pharmacology , Chickens/microbiology , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/drug effects , Escherichia coli/genetics , Fluoroquinolones/pharmacology , Animals , DNA Gyrase/genetics , DNA Topoisomerase IV/genetics , Dose-Response Relationship, Drug , Enrofloxacin , Microbial Sensitivity Tests , Mutation
18.
Article in Chinese | MEDLINE | ID: mdl-21162201

ABSTRACT

AIM: To screen swimming-fatigue related genes in mice and lay theoretic basis for researching the molecular mechanism of fatigue. METHODS: 30 male BALB/c mice (20 +/- 2g) were divided into control group, dipping in water group and swimming-fatigue group respectively. After fatigue for swimming in swimming-fatigue group, with control group and dipping in water group, liver tissues in mice were collected. With improved silver staining mRNA differential display method, the differentially expressed genes in mice livers were screened and evaluated by reversed Northern blot. The positive segments were analyzed homology by BLAST. RESULTS: 7 of DD-ESTs were gained. Two of them only expressed in swimming-fatigue group, two down-regulated expressed, and three up-regulated. One of them was a novel gene and was accepted by GenBank, AY615302. CONCLUSION: Seven DD-ESTs in swimming-fatigue mice were gained by silver staining mRNA differential display method.


Subject(s)
Fatigue/metabolism , Gene Expression Profiling/methods , Liver/metabolism , Polymerase Chain Reaction/methods , Animals , Male , Mice , Mice, Inbred BALB C , Molecular Sequence Data , RNA, Messenger/genetics , Silver Staining , Swimming
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