Microorganisms are the dominant players driving the degradation and transformation of chloramphenicol (CAP) in the environment. However, little bacterial strains are able to efficiently degrade and mineralize CAP, and the CAP degrading pathways mediated by oxidative reactions remain unclear. In this study, a highly efficient CAP-degrading microbial consortium, which mainly consists of Rhodococcus (relative abundance >70%), was obtained through an enrichment process using CAP-contaminated activated sludge as the inoculum. A bacterial strain CAP-2 capable of efficiently degrading CAP was isolated from the consortium and identified as Rhodococcus sp. by 16S rRNA gene analysis. Strain CAP-2 can efficiently degrade CAP under different nutrient conditions. Based on the biotransformation characteristics of the detected metabolite p-nitrobenzoic acid and the reported metabolites p-nitrobenzaldehyde and protocatechuate by strain CAP-2, a new oxidative pathway for the degradation of CAP was proposed. The side chain of CAP was oxidized and broken to generate p-nitrobenzaldehyde, which was further oxidized to p-nitrobenzoic acid. Strain CAP-2 can be used to further study the molecular mechanism of CAP catabolism, and has the potential to be used in in situ bioremediation of CAP-contaminated environment.
Biodegradation, Environmental ; Chloramphenicol ; RNA, Ribosomal, 16S/genetics* ; Rhodococcus/genetics* ; Sewage

OBJECTIVE: To improve and establish the mouse model with aplastic anemia (AA) mediated by Cs γ-ray irradiation combined with cyclophosphamide (CTX) and chloramphenicol (CHL) injection,so as to provide a stable model for studying the pathogenesis and treatment of AA . METHODS: The BALB/c mice were exposed to Cs γ-ray of 3-5 Gy(91 cGy/min) and were intraperitoneally injected with CTX of 25 mg/(kg.d) and CHL of 62.5 mg/(kg.d) at D 4,5 and 6 after irradiation; the WBC, platelet and reticulocyte counts in peripheral blood as well as the mucleated cell count in bone marrow and bone marrow smears were detected . RESULTS: The 3-lineage cells in peripheral blood of BALB/c mouse model with acquired AA were rapidly reduced, especially WBC, platelet and reticulocyte counts were lowest at D 14,the 3-lineage cells in peripheral blood were still severely reduced at D 28; the nucleated cell count in bone marrow significantly dcreased,the bone marrow hyperplasia was reduced or severely reduced; the pathological sections of bone marrow showed the severe reduction of hematopoietic cells and the increased of non-hematopoietic cells such as fat cells. CONCLUSION The mouse model with acquired AA has been established by Cs γ-ray irradiation combined with CTX and CHL injection. All detection indicators of this model reach to diagnostic criteria for acquired AA,therefore this mouse model may be used as the model for study of pathogenesis and treatment of acquired AA.
Anemia, Aplastic ; Animals ; Chloramphenicol ; Cyclophosphamide ; Gamma Rays ; Mice ; Mice, Inbred BALB C

Hematopoiesis has a pivotal role in the maintenance of body homeostasis. Ironically, several hematological disorder caused by chemicals, drugs, and other environmental factors lead to severe bone marrow failure. Current treatments like stem cell transplantation and immunosuppression remain ineffective to ameliorate this diseases. Therefore, a newtreatment to overcome this entity is necessary, one of them by promoting the usage of medicinal plants. Thus, this study aimed to evaluate the hematopoiesis potency of S. javanica berries and leaves extracts in chloramphenicol (CMP)-induced aplastic anemia mice model. In this present study, several types of blood progenitor cell such as TER-119⁺VLA-4⁺ erythrocytes lineage, Gr-1⁺ granulocytes, and B220⁺ B-cell progenitor cells were evaluated by flow cytometry analysis. Accordingly, we revealed that S. javanica berries and leaves extracts significantly promoted TER-119⁺VLA-4⁺ erythrocytes lineage and Gr-1⁺ granulocytes after exposed by CMP. Thus, these results suggested that S. javanica berries and leaves extracts might have hematopoiesis activity in CMP-induced aplastic anemia mice model.
Anemia, Aplastic ; Animals ; B-Lymphocytes ; Bone Marrow ; Chloramphenicol ; Erythrocytes ; Flow Cytometry ; Fruit ; Granulocytes ; Hematopoiesis ; Homeostasis ; Immunosuppression ; Iron ; Mice ; Plants, Medicinal ; Sambucus ; Stem Cell Transplantation ; Stem Cells

To establish appropriate conditions for a disinfectant efficacy test at subzero temperatures, this study examined mixtures of frozen foot-and-mouth disease virus or avian influenza virus solutions and disinfectant diluents at −5℃ and monitored temperature and freezing status of an anti-freezing diluent (AFD, 15% ethanol + 30% propylene glycol + 55% distilled water) over time at various subzero temperatures. Viral solutions and disinfectant diluents froze before the mixtures reached −5℃, whereas the AFD was not frozen at −30℃. The times taken for the AFD to reach −10, −20, −30, and −40℃ from room temperature were 36, 39, 45, and 48 min, respectively.
Animals ; Ethanol ; Foot-and-Mouth Disease Virus ; Freezing ; Influenza in Birds ; Propylene Glycol

The present study was designed to examine the effect of heme oxygenase-1 (HO-1) induction by cobalt protoporphyrin (CoPP) on the cardiac functions and morphology, electrocardiogram (ECG) changes, myocardial antioxidants (superoxide dismutase [SOD] and glutathione [GSH]), and expression of heat shock protein (Hsp) 70 and connexin 43 (Cx-43) in myocardial muscles in isoproterenol (ISO) induced myocardial infarction (MI). Thirty two adult male Sprague Dawely rats were divided into 4 groups (each 8 rats): normal control (NC) group, ISO group: received ISO at dose of 150 mg/kg body weight intraperitoneally (i.p.) for 2 successive days; ISO + Trizma group: received (ISO) and Trizma (solvent of CoPP) at dose of 5 mg/kg i.p. injection 2 days before injection of ISO, with ISO at day 0 and at day 2 after ISO injections; and ISO + CoPP group: received ISO and CoPP at a dose of 5 mg/kg dissolved in Trizma i.p. injection as Trizma. We found that, administration of ISO caused significant increase in heart rate, corrected QT interval, ST segment, cardiac enzymes (lactate dehydrogenase, creatine kinase-muscle/brain), cardiac HO-1, Hsp70 with significant attenuation in myocardial GSH, SOD, and Cx-43. On the other hand, administration of CoPP caused significant improvement in ECG parameters, cardiac enzymes, cardiac morphology; antioxidants induced by ISO with significant increase in HO-1, Cx-43, and Hsp70 expression in myocardium. In conclusions, we concluded that induction of HO-1 by CoPP ameliorates ISO-induced myocardial injury, which might be due to up-regulation of Hsp70 and gap junction protein (Cx-43).
Adult ; Animals ; Antioxidants ; Body Weight ; Cobalt ; Connexin 43 ; Connexins ; Creatine ; Electrocardiography ; Glutathione ; Hand ; Heart Rate ; Heat-Shock Proteins ; Heme Oxygenase-1 ; Heme ; HSP70 Heat-Shock Proteins ; Humans ; Isoproterenol ; Male ; Muscles ; Myocardial Infarction ; Myocardium ; Oxidoreductases ; Rats ; Tromethamine ; Up-Regulation

BACKGROUND: Campylobacter jejuni is an important food-borne pathogen that causes human gastroenteritis. This study was conducted to investigate the incidence of isolation, antimicrobial susceptibility pattern, and C. jejuni genotype from diarrhea patients in Busan, Korea. METHODS: A total of 97 C. jejuni were isolated from diarrhea patients during five food-borne outbreaks from 2014 to September 2017. Antimicrobial susceptibility tests were carried out by the broth microdilution method for ciprofloxacin (CIP), nalidixic acid (NAL), tetracycline (TET), chloramphenicol, azithromycin (AZI), erythromycin (ERY), streptomycin (STR), gentamicin, and telithromycin. To investigate C. jejuni genotypes, pulsed-field gel electrophoresis (PFGE) profile analysis was performed. RESULTS: The isolation rate of C. jejuni was 2.0% for the last 4 years and increased annually. Antimicrobial resistance rates of C. jejuni were shown to be in the order of NAL (90.9%), CIP (89.4%), TET (13.6%), AZI (3.0%), ERY (3.0%), and STR (1.5%). The proportion of multidrug-resistance was 18.2%, and they commonly contained quinolones (CIP-NAL). Analysis of PFGE patterns of SmaI-restricted DNA of C. jejuni isolates showed 17 clusters; cluster 11 was the major genotype pattern. CONCLUSION: This study will provide useful data for the proper use of antimicrobials and the management of resistant C. jejuni. Also it will help to provide data for the epidemiological investigation of foodborne diseases caused by C. jejuni, which is expected to increase in the future.
Azithromycin ; Busan ; Campylobacter jejuni ; Campylobacter ; Chloramphenicol ; Ciprofloxacin ; Diarrhea ; Disease Outbreaks ; DNA ; Electrophoresis, Gel, Pulsed-Field ; Erythromycin ; Foodborne Diseases ; Gastroenteritis ; Genotype ; Gentamicins ; Humans ; Incidence ; Korea ; Methods ; Nalidixic Acid ; Quinolones ; Streptomycin ; Tetracycline

BACKGROUND: Salmonella is an important pathogen that causes gastroenteritis and sepsis in humans. Recently, changes in serotype prevalence and an increase in antimicrobial resistance have been reported. This study investigated the distribution of Salmonella serotypes and determined the antimicrobial susceptibility of various strains. METHODS: We collected 113 Salmonella isolates other than Salmonella serotype Typhi from 18 university hospitals in 2015. The serotypes were identified by Salmonella antisera O and H according to the Kauffman White scheme. Antimicrobial susceptibility tests for 12 antibiotics were performed using the disk diffusion method or E-test. RESULTS: We identified 22 serotypes. Serotype group B (44.2%) was the most common, followed by groups C (34.5%) and D (21.2%). Salmonella I 4,[5],12:i:- (23.0%), S. Enteritidis (16.8%), and S. Typhimurium (12.4%) were the most common species. Resistance rates for ampicillin, chloramphenicol, ceftriaxone, and trimethoprim/sulfamethoxazole were 46.9%, 18.5%, 8.8%, and 5.3%, respectively. The intermediate resistance rate to ciprofloxacin was 29.2%. Six isolates were extended-spectrum β-lactamase (ESBL) producers, including 5 bla(CTX-M-15) and 1 bla(CTX-M-55). CONCLUSION: There have been changes in the serotype prevalence and antimicrobial resistance of Salmonella in Korea, with a high prevalence of CTX-M 15-positive strains. Continuous monitoring of Salmonella serotypes and antimicrobial resistance is warranted.
Ampicillin ; Anti-Bacterial Agents ; Ceftriaxone ; Chloramphenicol ; Ciprofloxacin ; Diffusion ; Gastroenteritis ; Hospitals, University ; Humans ; Immune Sera ; Korea ; Methods ; Prevalence ; Salmonella ; Sepsis ; Serogroup ; Serotyping

Anthrax, caused by Bacillus anthracis, is a non-contagious infectious disease that affects a wide range of animal species (primarily ruminants) including humans. Due to the often-fatal outcome in humans, quick administration of definitely effective antimicrobials is crucial either as prophylaxis or as a clinical case therapy. In this study, 110 B. anthracis strains, temporally, geographically, and genetically different, isolated during anthrax outbreaks in Italy from 1984 to 2017, were screened using a broth microdilution method to determine their susceptibility to 16 clinically relevant antimicrobial agents. The strains were isolated from various matrices (human, animal, and environmental samples) and were representative of thirty distinct genotypes previously identified by 15-loci multiple-locus variable-number of tandem repeats analysis. The antimicrobials tested were gentamicin, ceftriaxone, streptomycin, penicillin G, clindamycin, chloramphenicol, vancomycin, linezolid, cefotaxime, tetracycline, erythromycin, rifampin, amoxicillin, ciprofloxacin, doxycycline, and trimethoprim. All isolates were susceptible to most of the tested antimicrobials, with the exception of trimethoprim for which all of them showed high minimal inhibitory concentration values. An intermediate level of susceptibility was recorded for ceftriaxone and cefotaxime. Although the Centers for Disease Control and Prevention recommend the use of doxycycline, ciprofloxacin, penicillin G, and amoxicillin for treatment of human cases and for post-exposure prophylaxis to anthrax spores, this study shows a high degree of in vitro susceptibility of B. anthracis to many other antimicrobials, suggesting the possibility of an alternative choice for prophylaxis and therapy.
Amoxicillin ; Animals ; Anthrax ; Anti-Infective Agents ; Bacillus anthracis ; Bacillus ; Cefotaxime ; Ceftriaxone ; Centers for Disease Control and Prevention (U.S.) ; Chloramphenicol ; Ciprofloxacin ; Clindamycin ; Communicable Diseases ; Disease Outbreaks ; Doxycycline ; Erythromycin ; Genotype ; Gentamicins ; Humans ; In Vitro Techniques ; Italy ; Linezolid ; Methods ; Microbial Sensitivity Tests ; Penicillin G ; Post-Exposure Prophylaxis ; Rifampin ; Spores ; Streptomycin ; Tandem Repeat Sequences ; Tetracycline ; Trimethoprim ; Vancomycin

PURPOSE: Neutrophils are considered key effector cells in the pathogenic mechanisms of airway inflammation in asthma. This study assessed the activation status of neutrophils in adult asthmatics, and the therapeutic potential of FTY720, a synthetic sphingosine-1-phosphate analog, on activated neutrophils using an in vitro stimulation model. METHODS: We isolated peripheral blood neutrophils (PBNs) from 59 asthmatic patients (including 20 aspirin-exacerbated respiratory disease [AERD] and 39 aspirin-tolerant asthma [ATA] groups). PBNs were stimulated with N-formyl-methionyl-leucyl-phenylalanine (fMLP) or lipopolysaccharide (LPS) and their activation status was determined based on reactive oxygen species (ROS) production, cell surface expression of CD11b, interleukin (IL)-8 and matrix metallopeptidase (MMP)-9 release. PBNs were primed with FTY720 to evaluate its anti-inflammatory action. RESULTS: In vitro PBN stimulation with fMLP or LPS induced a significant increase in ROS/CD11b/IL-8/MMP-9 levels (P < 0.05 for all). In asthmatics, fMLP-induced ROS level was significantly correlated with values of forced expiratory volume in 1 second/forced vital capacity (r = −0.278; P = 0.036), maximal mid-expiratory flow (r = −0.309; P = 0.019) and PC20 methacholine (r = −0.302; P = 0.029). In addition, ROS levels were significantly higher in patients with AERD and in those with severe asthma than in those with ATA or non-severe asthma (P < 0.05 for all). FTY720 treatment could suppress ROS/CD11b levels, and LPS-induced IL-8 and MMP-9 levels (P < 0.05 for all). Responders to FTY720 treatment had significantly higher neutrophil counts in sputum (P = 0.004). CONCLUSIONS: Our findings suggest a useful in vitro PBN stimulation model for evaluating the neutrophil functional status and the therapeutic potentials of neutrophil-targeting candidates in asthmatics.
Adult ; Asthma ; Fingolimod Hydrochloride ; Forced Expiratory Volume ; Humans ; In Vitro Techniques ; Inflammation ; Interleukin-8 ; Interleukins ; Methacholine Chloride ; N-Formylmethionine Leucyl-Phenylalanine ; Neutrophil Activation ; Neutrophils ; Phenotype ; Reactive Oxygen Species ; Sputum ; Vital Capacity

Clostridium perfringens causes diarrhea and other diseases in animals and humans. We investigated the prevalence, toxin gene profiles, and antibiotic resistance of C. perfringens isolated from diarrheic dogs (DD) and non-diarrheic dogs (ND) in two animal hospitals in Seoul, Korea. Fecal samples were collected from clinically DD (n = 49) and ND (n = 34). C. perfringens was isolated from 31 of 49 DD (63.3%) and 21 of 34 ND dogs (61.8%). All C. perfringens strains were positive for the α toxin gene, but not for the β, ε, or ι toxin genes; therefore, all strains were identified as type A C. perfringens. All isolates were cpe-negative, whereas the β2 toxin gene was identified in 83.9% and 61.9% of isolates from DD and ND, respectively. Most isolates were susceptible to ampicillin (94%), chloramphenicol (92%), metronidazole (100%), moxifloxacin (96%), and imipenem (100%). However, 25.0% and 21.2% of isolates were resistant to tetracycline and clindamycin, respectively. Molecular subtyping of the isolated strains was performed by using pulsed-field gel electrophoresis. Fifty-two isolates were classified into 48 pulsotypes based on more than 90% similarity of banding patterns. No notable differences were observed among the isolates from DD and ND.
Ampicillin ; Animals ; Bacterial Toxins ; Chloramphenicol ; Clindamycin ; Clostridium perfringens ; Clostridium ; Diarrhea ; Dogs ; Drug Resistance ; Drug Resistance, Microbial ; Electrophoresis, Gel, Pulsed-Field ; Hospitals, Animal ; Humans ; Imipenem ; Korea ; Metronidazole ; Prevalence ; Seoul ; Tetracycline