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Sample records for chloramphenicol

  1. Chloramphenicol acetyltransferase should not provide methanogens with resistance to chloramphenicol.

    OpenAIRE

    Beckler, G S; Hook, L A; Reeve, J N

    1984-01-01

    Growth of the four methanogens investigated was inhibited by chloramphenicol-3-acetate; therefore, introduction of chloramphenicol acetyltransferase-encoding genes should not confer chloramphenicol resistance on these methanogens. Reduction of the aryl nitro group of chloramphenicol produced a compound which did not inhibit the growth of these methanogens.

  2. Chemiluminescence immunoassay for chloramphenicol

    International Nuclear Information System (INIS)

    A simple, solid-phase chemiluminescence immunoassay (CLIA) for the measurement of Chloramphenicol(CAP) in foodstuffs is described. A rabbit anti-CAP IgG is passively adsorbed onto the walls of polypropylene plates. The labeled conjugant is horseradish peroxidase(HRP) conjugate of CAP. Luminol solution is used as the substrate of HRP. The light yield is inversely proportional to the concentration of CAP. The method has a similar sensitivity (0.05 ng/mL), specificity, precision, and accuracy to a conventional enzyme immunoassay (EIA). The intra-assay and inter-assay CVs of ten samples were <8 and <20%, respectively, and the analytical recovery of the method was 87% 100%. The experimental correlation coefficient of dilution was found to be 0.999 using milk supernatant as buffer. The assay range for the method was 0.1-10 ng/mL, and it displayed good linearity. (authors)

  3. Compound list: chloramphenicol [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available chloramphenicol CMP 00064 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Hu...man/in_vitro/chloramphenicol.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST.../Rat/in_vitro/chloramphenicol.Rat.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/...iosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/chloramphenicol.Rat.in_vivo.Liver.Repeat.zip ...

  4. A pharmacological study of chloramphenicol in horses.

    Science.gov (United States)

    Sisodia, C S; Kramer, L L; Gupta, V S; Lerner, D J; Taksas, L

    1975-04-01

    Pharmacological disposition of chloramphenicol was studied in horses. Minimum levels of the antibiotic (greater than or equal to 5 mu g/ml) in blood or plasma recommended to combat infections could not be achieved by 4.4 and 8.8 mg/kg I.V. or 30 and 50 mg/kg I.M. or 30 mg/kg oral (as palmitate salt) doses of chloramphenicol. Increasing the dose to 19.8 and 26.4 mg/kg I.V. provided such levels for about two and three hours respectively. A combination of 20 mg/kg I.V. and 30 mg/kg I.M. administered simultaneously did not provide more prolonged levels than 26.4 mg/kg I.V. alone. Chloramphenicol succinate produced higher but not more prolonged levels in blood and plasma than those produced by pure chloramphenicol. Succinate salt is very little, if at all, bound to red blood corpuscles. Plasma half life and the apparent volume of distribution of chloramphenicol in horses were determined as 0.98 hours and 0.92 L/kg, respectively. At 5-10 mu g/ml concentrations in equine plasma approximately 30 percent of the chloramphenicol is bound to plasma proteins. From these studies it is concluded that the biological half life of chloramphenicol may be too short for therapeutic application against systemic infections in horses. PMID:1125836

  5. Radiolysis characterization of chloramphenicol in powder and in eye ointment

    International Nuclear Information System (INIS)

    The effects of γ-radiation sterilization on chloramphenicol, in both pure powder state and petrolatum eye ointment, were investigated with high performance liquid chromatography. The content of chloramphenicol decreases by 1.0% in powder state and by 1.2% in eye ointment at the reference radiation dose of 25 kGy. The profile of chloramphenicol radiolysis products in powder state differs from that in eye ointment. It was found that microenvironment of chloramphenicol molecule is a key factor governing the radiolysis of chloramphenicol in powder state. Solvent residues in chloramphenicol powder could change the radiolysis behavior of chloramphenicol. The solvents, having good solubility for chloramphenicol, promote radiolytic hydrolysis of chloramphenicol, but the converses do not. Inert gas purging or diffusion by exposing in absorbent is efficient method to prevent chloramphenicol powder from radiolysis. The influence of the presence of oxygen was explored. Oxygen plays a role of scavenger and diminishes radiolysis of chloramphenicol. It was found that Nactyl-L-cysteine can protection chloramphenicol in eye ointment from radiolysis. Hydrophobic radiolysis products of chloramphenicol were observed in eye ointment part. Using scavengers and lower irradiation can be strategies to resist radiolysis of chloramphenicol in petrolatum eye ointment. (author)

  6. Characterization of two metagenome-derived esterases that reactivate chloramphenicol by counteracting chloramphenicol acetyltransferase.

    Science.gov (United States)

    Tao, Weixin; Lee, Myung Hwan; Yoon, Mi-Young; Kim, Jin-Cheol; Malhotra, Shweta; Wu, Jing; Hwang, Eul Chul; Lee, Seon-Woo

    2011-12-01

    Function-driven metagenomic analysis is a powerful approach to screening for novel biocatalysts. In this study, we investigated lipolytic enzymes selected from an alluvial soil metagenomic library, and identified two novel esterases, EstDL26 and EstDL136. EstDL26 and EstDL136 reactivated chloramphenicol from its acetyl derivates by counteracting the chloramphenicol acetyltransferase (CAT) activity in Escherichia coli. These two enzymes showed only 27% identity in amino acid sequence to each other; however both preferentially hydrolyzed short-chain p-nitrophenyl esters (lipase (HSL), and since chloramphenicol acetate esterase (CAE) activity was detected from two other soil esterases in the HSL family, this suggests a distribution of CAE among the soil microorganisms. The isolation and characterization of EstDL26 and EstDL136 in this study may be helpful in understanding the diversity of CAE enzymes and their potential role in releasing active chloramphenicol in the producing bacteria. PMID:22210605

  7. Erythromycin induces expression of the chloramphenicol acetyltransferase gene cat-86.

    OpenAIRE

    Rogers, E J; Lovett, P S

    1990-01-01

    The plasmid gene cat-86 specifies chloramphenicol-inducible chloramphenicol acetyltransferase in Bacillus subtilis. This gene, like the erythromycin-inducible erm genes, is regulated by translational attenuation. Here we show that cat-86 is also inducibly regulated by erythromycin. cat-86 does not confer resistance to erythromycin.

  8. 21 CFR 520.390a - Chloramphenicol tablets.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chloramphenicol tablets. 520.390a Section 520.390a... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.390a Chloramphenicol tablets. (a)(1) Specifications. Each tablet contains 100, 250, or 500 milligrams, 1 or 2.5 grams...

  9. 21 CFR 524.390a - Chloramphenicol ophthalmic ointment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chloramphenicol ophthalmic ointment. 524.390a... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.390a Chloramphenicol ophthalmic ointment. (a) Specifications. Each gram contains 10...

  10. 21 CFR 524.390b - Chloramphenicol ophthalmic solution.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chloramphenicol ophthalmic solution. 524.390b... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.390b Chloramphenicol ophthalmic solution. (a) Specifications. Each milliliter contains...

  11. Radiolysis of chloramphenicol and its eye ointment during gamma sterilisation

    International Nuclear Information System (INIS)

    The effects of γ radiation sterilisation on chloramphenicol (CAP), both in pure powder state and in eye ointment, were investigated with high performance liquid chromatography (HPLC) and HPLC-MS. Five radiation degradation products were observed and identified, the radiolysis mechanisms were elucidated, and the application of γ radiation sterilisation on chloramphenicol was discussed. It has been determined that at irradiation dose of 25 kGy, the content of chloramphenicol decreases by 1.0% in powder state and by 3.3% in eye ointment. By comparing the radiolytic products of CAP in different matrices, it is concluded hydrolysis, oxidation and radical reduction are the main radiolytical degradation reactions of chloramphenicol, and the micro-environment surrounding chloramphenicol molecular plays an important role in the radiolysis process. Protection techniques to resist radiolyses are thus proposed based on the experimental findings. (author)

  12. Rapid quantitative assay for chloramphenicol acetyltransferase

    International Nuclear Information System (INIS)

    Measuring the expression of exogenous genetic material in mammalian cells is commonly done by fusing the DNA of interest to a gene encoding an easily-detected enzyme. Chloramphenicol acetyltransferase(CAT) is a convenient marker because it is not normally found in eukaryotes. CAT activity has usually been detected using a thin-layer chromatographic separation followed by autoradiography. An organic solvent extraction-based method for CAT detection has also been described, as well as a procedure utilizing HPLC analysis. Building on the extraction technique, they developed a rapid sensitive kinetic method for measuring CAT activity in cell homogenates. The method exploits the differential organic solubility of the substrate ([3H] or [14C]acetyl CoA) and the product (labeled acetylchloramphenicol). The assay is a simple one-vial, two-phase procedure and requires no tedious manipulations after the initial setup. Briefly, a 0.25 ml reaction with 100mM Tris-HCL, 1mM chloramphenicol, 0.1mM [14C]acetyl CoA and variable amounts of cell homogenate is pipetted into a miniscintillation vial, overlaid with 5 ml of a water-immiscible fluor, and incubated at 370C. At suitable intervals the vial is counted and the CAT level is quantitatively determined as the rate of increase in counts/min of the labeled product as it diffuses into the fluor phase, compared to a standard curve. When used to measure CAT in transfected Balb 3T3 cells the method correlated well with the other techniques

  13. Electrochemical degradation of the chloramphenicol at flow reactor

    International Nuclear Information System (INIS)

    This paper reports a study of electrochemical degradation of the chloramphenicol antibiotic in aqueous medium using a flow-by reactor with DSA anode. The process efficiency was monitored by chloramphenicol concentration analysis with liquid chromatography (HPLC) during the experiments. Analysis of Total Organic Carbon (TOC) was performed to estimate the degradation degree and Ion Chromatography (IC) was performed to determinate inorganic ions formed during the electrochemical degradation process. In electrochemical flow-by reactor, 52% of chloramphenicol was degraded, with 12% TOC reduction. IC analysis showed the production of chloride ions (25 mg L-1), nitrate ions (6 mg L-1) and nitrite ions (4.5 mg L-1). (author)

  14. Determination of chloramphenicol (CAP) residues in trout by radioimmunoassay

    International Nuclear Information System (INIS)

    Chloramphenicol (CAP) concentrations in the muscle of rainbow trout from natural lakes, culture pools and markets were determined by radioimmunoassay technique. Chloramphenicol concentrations in the fish muscle samples from natural lakes were found in the ranges of 0-0.8 ng/g. In the fish muscle samples from markets and aqua cultured Chloramphenicol was not observed. The results from natural lakes will provide a basis for determination of the detection limit of CAP for other laboratories to be established in the future where analyses will be carried out regularly. (author)

  15. Pseudosecretion of Escherichia coli chloramphenicol acetyltransferase by Bacillus subtilis.

    OpenAIRE

    Le Grice, S F; Gentz, R; Bannwarth, W; Kocher, H. P.

    1987-01-01

    Bacillus subtilis harboring the vector 25RBSII secrets an Escherichia coli-derived chloramphenicol acetyltransferase into culture supernatants. The secreted enzyme lacks 18 amino acids; these are removed externally rather than during secretion.

  16. Inhibition of existing denitrification enzyme activity by chloramphenicol.

    OpenAIRE

    Brooks, M H; Smith, R L; Macalady, D L

    1992-01-01

    Chloramphenicol completely inhibited the activity of existing denitrification enzymes in acetylene-block incubations with (i) sediments from a nitrate-contaminated aquifer and (ii) a continuous culture of denitrifying groundwater bacteria. Control flasks with no antibiotic produced significant amounts of nitrous oxide in the same time period. Amendment with chloramphenicol after nitrous oxide production had begun resulted in a significant decrease in the rate of nitrous oxide production. Chlo...

  17. Assaying the reporter gene chloramphenicol acetyltransferase

    International Nuclear Information System (INIS)

    These experiments document the presence of enzymatic activities in extracts of commonly used cell lines which interfere with the determination of CAT activity. We suspect that the deacetylase activity is the most important, as the extract of the H4IIE C3 cells was capable of completely deacetylating the mono- and diacetylchloramphenicol formed during a 2-hr incubation of CAT with chloramphenicol and acetyl-CoA. The results of the inhibitor experiments are consistent with the presence of proteases which degrade CAT, or a serine carboxylesterase. The interference was also reduced by about half by EDTA; a metalloenzyme (either a protease or esterase) may therefore be involved. This interference appears to be a common phenomenon. We have surveyed 23 different cell types for the presence of the interfering activity and found it in 15. The interference was particularly prominent in several neuroendocrine and hepatoma cells. We took advantage of the effect of EDTA and the heat stability of CAT to eliminate the interference. Addition of 5 mM EDTA and a 10-min incubation of the sonicated cell suspension at 60 degrees prior to centrifugation abolished the interference in all cell lines tested. It is important to note that in order to reveal any CAT activity in some of the extracts (e.g., PC-12 or Hep3B), it was necessary to run the CAT assay for 2 hr. The control assays were therefore run almost to completion, and were well beyond the linear range of the assay. Therefore, the small differences which we observed between the heat-treated and control samples in some instances (e.g., rice, corn, or HeLa cells) will be dramatically amplified when the CAT assay is performed under conditions in which only a small percentage of the substrate is converted to product

  18. Chloramphenicol Inhibition of Denitrifying Enzyme Activity in Two Agricultural Soils

    OpenAIRE

    Murray, Robert E.; Knowles, Roger

    1999-01-01

    Chloramphenicol, at concentrations greater than 0.1 g/liter (0.3 mM), inhibited the denitrifying enzyme activity (DEA) of slurries of humisol and sandy loam soils by disrupting the activity of existing nitrate reductase enzymes. When the concentration of chloramphenicol was increased from 0.1 to 2.0 g/liter (6.0 mM), the rate of nitrite production from nitrate decreased by 25 to 46%. The rate of NO production from nitrate decreased by 20 to 39%, and the rate of N2O production from nitrate, in...

  19. Rapid, sensitive, and inexpensive assay for chloramphenicol acetyltransferase

    International Nuclear Information System (INIS)

    We present a rapid, sensitive enzymatic assay for chloramphenicol acetyltransferase (CAT) that does not require chromatography, HPLC, or autoradiography. The assay is based on the use of an inexpensive substrate, tritiated acetate, instead of [14C]chloramphenicol. The method is adapted from one originally used by de Crombrugghe et al. and by Shaw, but with simplifications appropriate for routine use. In our hands, the method is as sensitive as the customary thin-layer chromatography assay and is far more efficient for the performance of many assays, both in terms of labor and expense

  20. Induction of Chloramphenicol and Tetracycline Resistance in Flexibacter sp. Strain FS-1

    OpenAIRE

    Barcak, G J; Burchard, R P

    1985-01-01

    The gliding bacterium Flexibacter sp. strain FS-1 exhibits inducible resistance to chloramphenicol (Cmr) and tetracycline (Tcr). Either chloramphenicol or tetracycline alone induced a Cmr Tcr phenotype. The resistance is apparently not plasmid encoded.

  1. A REVIEW OF THERAPEUTIC MONITORING OF CHLORAMPHENICOL IN PATIENTS WITH HAEMOPHILUS-INFLUENZAE MENINGITIS

    NARCIS (Netherlands)

    COAKLEY, JC; HUDSON, [No Value; SHANN, F; CONNELLY, JF

    1992-01-01

    Two hundred and seventy-seven serum chloramphenicol concentrations in 90 patients with Haemophilus influenzae type b meningitis were analysed retrospectively- Most patients were given chloramphenicol 25 mg/kg 6 hourly initially. Chloramphenicol concentrations were categorized as pre-dose ('trough')

  2. Pharmacokinetic, residue and irritation aspects of chloramphenicol sodium succinate and a chloramphenicol base formulation following intramuscular administration to ruminants.

    Science.gov (United States)

    Nouws, J F; Vree, T B; Holtkamp, J; Baakman, M; Driessens, F; Guelen, P J

    1986-07-01

    The disposition of chloramphenicol (CAP) and of its glucuronide metabolite in plasma and milk was studied following a single intramuscular injection of a chloramphenicol base formulation (Amicol Forte; product A) and of chloramphenicol sodium succinate (product B) to dairy cows. The dose applied of both formulations was equivalent to 50 mg CAP base/kg body weight. The HPLC determined CAP concentrations were microbiologically active. Product A revealed 30% higher plasma CAP peak concentrations (13.0 vs 9.0 micrograms/ml) and 36% larger areas under the plasma concentration-time curves than product B, whereas their absorption and elimination half-lives were of the same order of magnitude. In the onset phase (during 4 h p.i.) unhydrolysed CAP sodium succinate could be detected in plasma and the glucuronide fraction was 26% of the parent drug. After 25 h p.i. the glucuronide fraction equalled that of the parent drug. The maximum CAP concentration in milk was for product B equal to, and for product A 80% of, the CAP plasma concentration. In milk no chloramphenicol glucuronide metabolites could be detected. HPLC methods for detecting ultra-trace CAP concentrations in edible tissues were developed by the employment of extraction with or without a clean-up procedure. Seven days after i.m. administration of product A and B to calves, the CAP residue concentrations in the kidney, liver, and muscle were less than 2 nanogram/g tissue. Traces of CAP residues could be still found at the injection site and in the urine. Chloramphenicol sodium succinate (product B) caused extensive tissue irritation at the injection site, while in the case of product A the irritation was limited.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3750804

  3. Examinations of hens' eggs on residues of Chloramphenicol using a radioimmunoassay

    International Nuclear Information System (INIS)

    In the Federal Republic of Germany the application of Chloramphenicol to animals used for human food supply is restricted by law. Milk and dairy products as well as hen's eggs and egg products are not allowed to contain more than 1 ppb Chloramphenicol. 18 hens were fed with water treated with Chloramphenicol. The eggs of the treated animals were then analysed by means of radioimmunoassay. The applied radioimmunoassay is suitable for routine analysis to a minimum detection limit of 1 ppb. 378 eggs from the Weser-Ems district were tested for Chloramphenicol. No sample contained Chloramphenicol. (orig.)

  4. Establishment of an enzyme linked immunoassay for chloramphenicol

    International Nuclear Information System (INIS)

    A sensitive and specific EIA for chloramphenicol (CAP) is established by using one anti-CAP polyclonal antibody. The antibody is coated on the microtiter plate. The labelled compound is horseradish peroxidase (HRP) conjugate of chloramphenicol. TMB-H2O2 solution is used as the substrate of HRP. The sensitivity of the assay is 0.046 μg/L. The intra- and inter-CVs of 10 samples are lower than 10% and 24%, respectively. The analytical recovery is 62%-145%. The correlative equation is y=3.988x-0.234, r=0.999, using milk supernatant as buffer. The analytical range is 0.1-10 μg/L. (authors)

  5. 21 CFR 524.390d - Chloramphenicol-prednisolone ophthalmic ointment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chloramphenicol-prednisolone ophthalmic ointment... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.390d Chloramphenicol-prednisolone ophthalmic ointment. (a) Specifications. Each...

  6. Radioimmunological determination of chloramphenicol in the saliva of lactating cows

    International Nuclear Information System (INIS)

    In an effort to search for noninvasive methods suitable to monitor compliance with the ban of chloramphenicol (CAP) in milkproducing animals, the pharmacokinetic behavior of this drug in bovine saliva was investigated. As revealed by studies using a radioimmunological assay, CAP appears following its intracisternal (i.c.) or subcutaneous (s.c.) administration in the saliva of lactating cows. The level of sensitivity of the method (1.5 ng CAP per g saliva) was reached 14 and 18 days after i.c. and s.c. administration, respectively. At present, the question must remain open as to whether the concentration of CAP in the saliva can serve as a reliable indicator for the enforcement of the highest permissible level set at 1 ng CAP per g of milk by German regulations. (orig.)

  7. Rapid Screening of chloramphenicol in Turbot with photobacterium phosphoreum DB

    Institute of Scientific and Technical Information of China (English)

    Zhu Lanlan; Wang Jingxue; Lin Hong; Wang Yaqun; Wang Jing; Mei Cexia

    2009-01-01

    A new, simple, rapid microbial assay was put forward for the detection of chloramphenicol (CAP) residues in Turbot muscles using luminescent bacteria DB (Photobacterium phosphoreum) as test organism. By the luminescence inhibition of DB, the concentrations of CAP were determined. CAP spiked in Turbot muscle tissues ranging from 0.5 to 100μg/kg was extracted using ethyl acetate and hexane. The method had a good recovery of 93.69% with a minimum detection limit of 0.65μg/kg. It can be performed within 30min following simple extraction. The method therefore proved to be advantageous over chromatographic procedures as it was inexpensive, quite sensitive and can be adopted for rapid screening of CAP in Turbot tissues.

  8. Recombinant genomes which express chloramphenicol acetyltransferase in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Gorman, C.M.; Moffat, L.F.; Howard, B.H.

    1982-09-01

    The authors constructed a series of recombinant genomes which directed expression of the enzyme chloramphenicol acetyltransferase (CAT) in mammalian cells. The prototype recombinant in this series, pSV2-cat, consisted of the beta-lactamase gene and origin of replication from pBR322 coupled to a simian virus 40 (SV40) early transcription region into which CAT coding sequences were inserted. Readily measured levels of CAT accumulated within 48 h after the introduction of pSV2-cat DNA into African green monkey kidney CV-1 cells. Because endogenous CAT activity is not present in CV-1 or other mammalian cells, and because rapid, sensitive assays for CAT activity are available, these recombinants provided a uniquely convenient system for monitoring the expression of foreign DNAs in tissue culture cells. To demonstrate the usefulness of this system, we constructed derivatives of pSV2-cat from which part or all of the SV 40 promoter region was removed. Deletion of one copy of the 72-base-pair repeat sequence in the SV40 promoter caused no significant decrease in CAT synthesis in monkey kidney CV-1 cells; however, an additional deletion of 50 base pairs from the second copy of the repeats reduced CAT synthesis to 11% of its level in the wild type. They also constructed a recombinant, pSVO-cat, in which the entire SV40 promoter region was removed and a unique HindIII site was substituted for the insertion of other promoter sequences.

  9. Photocatalytic degradation of the antibiotic chloramphenicol and effluent toxicity effects.

    Science.gov (United States)

    Lofrano, Giusy; Libralato, Giovanni; Adinolfi, Roberta; Siciliano, Antonietta; Iannece, Patrizia; Guida, Marco; Giugni, Maurizio; Volpi Ghirardini, Annamaria; Carotenuto, Maurizio

    2016-01-01

    Chloramphenicol sodium succinate (CAP, C15H15Cl2N2 Na2O8) is a broad-spectrum antibiotic exhibiting activity against both Gram-positive and Gram-negative bacteria as well as other groups of microorganisms only partially removed by conventional activated sludge wastewater treatment plants. Thus, CAP and its metabolites can be found in effluents. The present work deals with the photocatalytic degradation of CAP using TiO2 as photocatalyst. We investigated the optimization of reaction contact time and concentration of TiO2 considering CAP and its by-products removal as well as effluent ecotoxicity elimination. Considering a CAP real concentration of 25mgL(-1), kinetic degradation curves were determined at 0.1, 0.2, 0.4, 0.8, 1.6 and 3.2gL(-1) TiO2 after 5, 10, 30, 60 and 120min reaction time. Treated samples were checked for the presence of by-products and residual toxicity (V. fischeri, P. subcapitata, L. sativum and D. magna). Results evidenced that the best combination for CAP and its by-products removal could be set at 1.6gL(-1) of TiO2 for 120min with an average residual toxicity of approximately 10%, that is the threshold set for negative controls in most toxicity tests for blank and general toxicity test acceptability. PMID:26256248

  10. Detoxification of the veterinary antibiotic chloramphenicol using electron beam irradiation.

    Science.gov (United States)

    Cho, Jae Young; Chung, Byung Yeoup; Hwang, Seon Ah

    2015-07-01

    Electron beam irradiation has shown potential as an alternative process for the treatment of industrial effluents that contain toxic organic chemicals. This study investigated the effectiveness of electron beam in degrading chloramphenicol (CAP) in aqueous solution. The degradation efficiency was 32.4% at 1 kGy, 86.9% at 5 kGy, and 100% at 10 kGy. The total organic carbon (TOC) of CAP in aqueous solution declined 4.6% at 1 kGy, 12.1% at 5 kGy, and 17.1% at 10 kGy of irradiation with electron beam. The CAP degradation products after irradiation were CAP1 ([M + H] m/z 307.1), CAP2 ([M + H] m/z 291.1), and CAP3 ([M + H] m/z 321.1). The degradation products were tested for microbial toxicity against Escherichia coli, Pseudomonas putida, and Bacillus subtilis and did not show any toxic antimicrobial effects caused by the CAP degradation products after irradiation with electron beam. The results of this study suggest that electron beam irradiation is the best technology for the comprehensive treatment of veterinary antibiotics at wastewater treatment plants. PMID:25616384

  11. Dissolution profile evaluation of solid pharmaceutical forms containing chloramphenicol marketed in Brazil

    OpenAIRE

    Humberto Gomes Ferraz; Leticia Norma Carpentieri; Sayuri Pereira Watanabe

    2007-01-01

    The dissolution profile for solid pharmaceutical forms containing chloramphenicol 250 mg available in Brazil was determined using a method from the American Pharmacopoeia (United States Pharmacopoeia, 2004) and then compared. Two different methods of dissolution profile comparison were used: ANOVA, and an independent model. Differences between the formulations were reflected in the dissolution profiles. The presence of metastable polymorphs or amorphous forms of chloramphenicol palmitate migh...

  12. Biomimetic piezoelectric quartz crystal sensor with chloramphenicol-imprinted polymer sensing layer.

    Science.gov (United States)

    Ebarvia, Benilda S; Ubando, Isaiah E; Sevilla, Fortunato B

    2015-11-01

    The measurement of banned antibiotic like chloramphenicol is significant for customer protection and safety. The presence of residual antibiotics in foods and food products of animal origin could pose as health hazards and affect food quality for global acceptance. In this study, the potential of a chloramphenicol sensor based on molecularly imprinted polymer (MIP) coupled with a piezoelectric quartz crystal was explored. The MIP was prepared by precipitation polymerization at 60 °C. Methacrylic acid was used as monomer, trimethylolpropane trimethacrylate (TRIM) as crosslinker, and chloramphenicol as the template. Template removal on the resulting polymer was done by extraction using methanol-acetic acid. Characterization of the MIP and NIP were conducted by spectroscopic and microscopic methods. These further supported the imprinting and rebinding process of chloramphenicol to the polymer matrix. The chloramphenicol sensor was devised by spin-coating onto one side of the 10 MHz AT-cut quartz crystal the MIP suspension in polyvinylchloride-tetrahydrofuran (6:2:1 w/w/v) solution. Optimization of sensor response was performed by varying the type of cross-linker, amount of MIP sensing layer, curing time, and pH. The sensor exhibited good sensitivity of about 73 Hz/log (conc., µg mL(-1)) and good repeatability (rsd<10%). A linear relationship (r(2)=0.9901) between frequency shift and chloramphenicol concentration in the range of 1×10(-6) up to 1×10(-1) µg/mL was obtained. The sensor response was highly selective to chloramphenicol than with other compounds of similar chemical structures. Acceptable percent recovery was obtained for real sample analysis using the sensor. The proposed sensor could be a promising low cost and highly sensitive approach for residual chloramphenicol quantification in food products. PMID:26452956

  13. In vitro susceptibility of chloramphenicol against methicillin-resistant staphylococcus aureus

    International Nuclear Information System (INIS)

    To determine the in vitro susceptibility of chloramphenicol against methicillin-resistant Staphylococcus aureus. Study Design: Cross-sectional study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from January to June 2012. Methodology: One hundred and seventy four isolates of methicillin-resistant Staphylococcus aureus were included in this study using cefoxitin (30 A g) disc for detection. Minimum inhibitory concentration (MIC) of chloramphenicol against MRSA was determined by using E-strip (AB BIO DISK). The susceptibility was determined by swabbing the Mueller-Hinton agar (MHA) plates with the resultant saline suspension of MRSA and applying E-strip of chloramphenicol from AB Biodisk Sweden and determining the MIC of chloramphenicol (in A g/ml). Clinical and Laboratory Standards Institute (CLSI) recommendations of A=8 A g/ml being sensitive, 16 A g/ml as intermediate and A 32 A g/ml as resistant were followed in interpreting the results. Results: Out of the 174 MRSA isolates, 132 (75.86%) isolates were susceptible to chloramphenicol with MICs of A=8 A g/ml, 38 (21.84%) were resistant A=32 A g/ml while 4 (2.30%) were in intermediate range with MIC of 16 A g/ml. Conclusion: Chloramphenicol has shown good in vitro activity against MRSA and is likely to have a key role in the treatment of MRSA infections providing us a good alternative to newer expensive antimicrobials in resource limited countries. (author)

  14. Radiation induced degradation of pharmaceutical residues in water: Chloramphenicol

    International Nuclear Information System (INIS)

    The γ-radiolytic degradation of chloramphenicol (CPL) was investigated in 0.1–1 mmol dm−3 aqueous solutions at various radiation conditions. The destruction of CPL was monitored by UV–vis spectrophotometric method through the decrease in the intensity of the absorbance band at 276 nm. LC-MS/MS was used to identify the degradation products. Results indicate that •OH can add onto the CPL aromatic ring or can abstract H-atom from the side chain. The reductive dechlorination of CPL was also studied based on the reaction of eaq− with CPL. In 0.1 mmol dm−3 solution above 2.5 kGy dose complete CPL degradation was achieved. In the presence of dissolved oxygen at relatively low dose, various oxidation products were observed. In the presence of tertiary butanol radical scavenger tertiary butanol group containing products were also detected. The toxicity increased as a function of dose to 1.0 kGy. At doses higher than 1.0 kGy the toxicity decreased continuously due to further degradation. It was also demonstrated that the O2−•/HO2• pair has low reactivity in CPL solution. - Highlights: ► At 0.1 mmol dm−3 concentration at 2.5 kGy complete CPL degradation was observed. ► At 0.1 mmol dm−3 concentration for mineralization 7–10 kGy is needed. ► First stable products are molecules hydroxylated in the ring or in the side chain. ► The toxicity of the solutions goes through a maximum as a function of dose.

  15. An In Vitro Synergistic Interaction of Combinations of Thymus glabrescens Essential Oil and Its Main Constituents with Chloramphenicol

    OpenAIRE

    Ilić, Budimir S.; Kocić, Branislava D.; Vojislav M. Ćirić; Cvetković, Olga G.; Miladinović, Dragoljub L.

    2014-01-01

    The chemical composition and antibacterial activity of Thymus glabrescens Willd. (Lamiaceae) essential oil were examined, as well as the association between it and chloramphenicol. The antibacterial activities of geraniol and thymol, the main constituents of T. glabrescens oil, individually and in combination with chloramphenicol, were also determined. The interactions of the essential oil, geraniol, and thymol with chloramphenicol toward five selected strains were evaluated using the microdi...

  16. Electrochemical degradation of the chloramphenicol at flow reactor; Degradacao eletroquimica do cloranfenicol em reator de fluxo

    Energy Technology Data Exchange (ETDEWEB)

    Rezende, Luis Gustavo P.; Prado, Vania M. do [Universidade Sao Francisco, Braganca Paulista, SP (Brazil); Rocha, Robson S. [Universidade Estadual de Campinas (DEMa/UNICAMP), SP (Brazil). Dept. de Engenharia de Materiais; Beati, Andre A.G.F. [Universidade Sao Francisco, Braganca Paulista, SP (Brazil). Dept. de Engenharia de Materiais; Sotomayor, Maria del Pilar T. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Quimica Analitica; Lanza, Marcos R.V., E-mail: marcoslanza@iqsc.usp.b [Universidade de Sao Paulo (IQSC/USP), Sao Carlos, SP (Brazil). Inst. de Quimica. Dept. de Quimica e Fisica Molecular

    2010-07-01

    This paper reports a study of electrochemical degradation of the chloramphenicol antibiotic in aqueous medium using a flow-by reactor with DSA anode. The process efficiency was monitored by chloramphenicol concentration analysis with liquid chromatography (HPLC) during the experiments. Analysis of Total Organic Carbon (TOC) was performed to estimate the degradation degree and Ion Chromatography (IC) was performed to determinate inorganic ions formed during the electrochemical degradation process. In electrochemical flow-by reactor, 52% of chloramphenicol was degraded, with 12% TOC reduction. IC analysis showed the production of chloride ions (25 mg L{sup -1}), nitrate ions (6 mg L{sup -1}) and nitrite ions (4.5 mg L{sup -1}). (author)

  17. An In Vitro Synergistic Interaction of Combinations of Thymus glabrescens Essential Oil and Its Main Constituents with Chloramphenicol

    Directory of Open Access Journals (Sweden)

    Budimir S. Ilić

    2014-01-01

    Full Text Available The chemical composition and antibacterial activity of Thymus glabrescens Willd. (Lamiaceae essential oil were examined, as well as the association between it and chloramphenicol. The antibacterial activities of geraniol and thymol, the main constituents of T. glabrescens oil, individually and in combination with chloramphenicol, were also determined. The interactions of the essential oil, geraniol, and thymol with chloramphenicol toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods. Oxygenated monoterpenes were the most abundant compound class in the oil, with geraniol (22.33% as the major compound. The essential oil exhibited in vitro antibacterial activity against all tested bacterial strains, but the activities were lower than those of the standard antibiotic and thymol. A combination of  T. glabrescens oil and chloramphenicol produced a strong synergistic interaction (FIC indices in the range 0.21–0.87 and a substantial reduction of the MIC value of chloramphenicol, thus minimizing its adverse side effects. The combinations geraniol-chloramphenicol and thymol-chloramphenicol produced synergistic interaction to a greater extent, compared with essential oil-chloramphenicol association, which may indicate that the activity of the thyme oil could be attributed to the presence of significant concentrations of geraniol and thymol.

  18. Sensitization of Micrococcus radiophilus to gamma-rays by postirradiation incubation with chloramphenicol or at nonpermissive temperature

    International Nuclear Information System (INIS)

    M. radiophilus was sensitized to gamma-rays by postirradiation incubation at 420C or at 300C in the presence of chloramphenicol. Radiation induced strand scissions and alkali labile bonds in DNA were repaired by post-irradiation incubation under normal conditions. However, these lesions were repaired only partially during the incubation at 420C or in the presence of chloramphenicol. (author)

  19. An In Vitro Synergistic Interaction of Combinations of Thymus glabrescens Essential Oil and Its Main Constituents with Chloramphenicol

    Science.gov (United States)

    Ilić, Budimir S.; Kocić, Branislava D.; Ćirić, Vojislav M.; Cvetković, Olga G.; Miladinović, Dragoljub L.

    2014-01-01

    The chemical composition and antibacterial activity of Thymus glabrescens Willd. (Lamiaceae) essential oil were examined, as well as the association between it and chloramphenicol. The antibacterial activities of geraniol and thymol, the main constituents of T. glabrescens oil, individually and in combination with chloramphenicol, were also determined. The interactions of the essential oil, geraniol, and thymol with chloramphenicol toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods. Oxygenated monoterpenes were the most abundant compound class in the oil, with geraniol (22.33%) as the major compound. The essential oil exhibited in vitro antibacterial activity against all tested bacterial strains, but the activities were lower than those of the standard antibiotic and thymol. A combination of  T. glabrescens oil and chloramphenicol produced a strong synergistic interaction (FIC indices in the range 0.21–0.87) and a substantial reduction of the MIC value of chloramphenicol, thus minimizing its adverse side effects. The combinations geraniol-chloramphenicol and thymol-chloramphenicol produced synergistic interaction to a greater extent, compared with essential oil-chloramphenicol association, which may indicate that the activity of the thyme oil could be attributed to the presence of significant concentrations of geraniol and thymol. PMID:24616649

  20. Moxifloxacin Lethality against Mycobacterium tuberculosis in the Presence and Absence of Chloramphenicol

    OpenAIRE

    Malik, Muhammad; Drlica, Karl

    2006-01-01

    The C-8-methoxy fluoroquinolone moxifloxacin was more lethal against chloramphenicol-treated Mycobacterium tuberculosis than Bay y3114, a C-8-H cognate of moxifloxacin, and two C-8-methoxy fluoroquinolones, gatifloxacin and BMS-433368, which have different C-7 substituents. Thus, an optimal combination of C-7 and C-8 substituents is likely to be important for killing nongrowing M. tuberculosis.

  1. Chloramphenicol acetyltransferase may confer resistance to fusidic acid by sequestering the drug.

    OpenAIRE

    Proctor, G N; McKell, J.; Rownd, R H

    1983-01-01

    Enterobacterial chloramphenicol acetyltransferase bound fusidic acid with high affinity, but did not acetylate the drug at an experimentally detectable rate. The enzyme may therefore confer resistance to fusidic acid by sequestering the drug and thereby preventing the drug from binding to translational elongation factor G.

  2. A comparative study of Cefixime and Chloramphenicole for treatment of patients with typhoid fever

    Directory of Open Access Journals (Sweden)

    Emadi J

    2001-08-01

    Full Text Available Typhoid fever is an endemic disease in Iran and other developing countries. This disease has gradually become resistant to the first line of drugs, and because of this resistancy we have studied a new alternative drug (cefixime on typhoid fever patients and compared it's effectiveness with chloramphenicol. For this purpose, by a randomized clinical trial in Emam Khomeini hospital between 1995-2000, we allocated 44 uncomplicated patient with established typhoid fever (positive blood or bone marrow culture and by random selection, 24 patient were given cefixime (400 mg PO bid and 20 patient received chloramphenicol (500 mg po Q6h. The duration of therapy were 10 and 14 days for chloramphenicol and cefixime group respectively. Median fever clearance times were 5±1.9 for cefixime recipients and 3.8±1.2 days for chloramphenicol treated patients, but for improvement in other clinical and laboratory findings, there were not any significant difference. Bacteriologic and clinical cure rate for cefixime was 100 and 92 percents respectively. Though, even cefixime like other betalactam drugs is slow in helping the fever disappearance but our study suggests that oral cefixime is effective and can be used as an alternate treatment of typhoid fever.

  3. Kinetics and mechanism of oxidation of chloramphenicol by 1-chlorobenzotriazole in acidic medium

    Indian Academy of Sciences (India)

    R C Hiremath; R V Jagadeesh; Puttaswamy; S M Mayanna

    2005-07-01

    Chloramphenicol (CAP) is an antibiotic drug having a wide spectrum of activity. The kinetics of oxidation of chloramphenicol by 1-chlorobenzotriazole (CBT) in HClO4 medium over the temperature range 293-323 K has been investigated. The reaction exhibits first-order kinetics with respect to [CBT]o and zero-order with respect to [CAP]o. The fractional-order dependence of rate on [H+] suggests complex formation between CBT and H+. It fails to induce polymerization of acrylonitrile under the experimental conditions employed. Activation parameters are evaluated. The observed solvent isotope effect indicates the absence of hydride transfer during oxidation. Effects of dielectric constant and ionic strength of the medium on the reaction rate have been studied. Oxidation products are identified. A suitable reaction scheme is proposed and an appropriate rate law is deduced to account for the observed kinetic data.

  4. A method to detect transfected chloramphenicol acetyltransferase gene expression in intact animals

    International Nuclear Information System (INIS)

    A rapid procedure is described for assaying chloramphenicol acetyltransferase enzyme activity in intact animals following transfection of the RSV CAT plasmid into mouse bone marrow cells by electroporation. The reconstituted mice were injected with [14C]chloramphenicol and ethyl acetate extracts of 24-h urine samples were analyzed by TLC autoradiography for the excretion of 14C-labeled metabolites. CAT expression in vivo can be detected by the presence of acetylated 14C-labeled metabolites in the urine within 1 week after bone marrow transplantation and, under the conditions described, these metabolites can be detected for at least 3 months. CAT expression in intact mice as monitored by the urine assay correlates with the CAT expression in the hematopoietic tissues assayed in vitro. This method offers a quick mode of screening for introduced CAT gene expression in vivo without sacrificing the mice

  5. Trace analysis of chloramphenicol residues in eggs, milk, and meat: comparison of gas chromatography radioimmunoassay

    International Nuclear Information System (INIS)

    A radioimmunological assay (RIA) to detect chloramphenicol (CAP) residues in eggs, milk, and meat is described. For tissues and other edible products of chloramphenicol-treated animals (chickens, cows, and pigs), the limit of detection is about 200 ng/kg. Residue levels above 1 μg/kg can easily be quantitated. When highly specific antisera produced in sheep were used, cross-reactivity was insignificant except for metabolites deviating from the parent compound in the acyl side chain only. Thiamphenicol fails to bind to the antisera; hence, it does not interfere with the assay. In the procedure described, the role of cleanup is merely to remove lipids. Thus, skim milk can be analyzed following appropriate dilution without cleanup. The results obtained by RIA were confirmed by gas chromatography with electron capture detection. The new RIA allows rapid, sensitive, and specific screening of large numbers of samples

  6. A conserved chloramphenicol binding site at the entrance to the ribosomal peptide exit tunnel

    DEFF Research Database (Denmark)

    Long, Katherine S; Porse, Bo T

    2003-01-01

    The antibiotic chloramphenicol produces modifications in 23S rRNA when bound to ribosomes from the bacterium Escherichia coli and the archaeon Halobacterium halobium and irradiated with 365 nm light. The modifications map to nucleotides m(5)U747 and C2611/C2612, in domains II and V, respectively......, of E.coli 23S rRNA and G2084 (2058 in E.coli numbering) in domain V of H.halobium 23S rRNA. The modification sites overlap with a portion of the macrolide binding site and cluster at the entrance to the peptide exit tunnel. The data correlate with the recently reported chloramphenicol binding site on...

  7. The effect of ethidium bromide and chloramphenicol on mitochondrial biogenesis in primary human fibroblasts

    International Nuclear Information System (INIS)

    The expression of mitochondrial components is controlled by an intricate interplay between nuclear transcription factors and retrograde signaling from mitochondria. The role of mitochondrial DNA (mtDNA) and mtDNA-encoded proteins in mitochondrial biogenesis is, however, poorly understood and thus far has mainly been studied in transformed cell lines. We treated primary human fibroblasts with ethidium bromide (EtBr) or chloramphenicol for six weeks to inhibit mtDNA replication or mitochondrial protein synthesis, respectively, and investigated how the cells recovered from these insults two weeks after removal of the drugs. Although cellular growth and mitochondrial gene expression were severely impaired after both inhibitor treatments we observed marked differences in mitochondrial structure, membrane potential, glycolysis, gene expression, and redox status between fibroblasts treated with EtBr and chloramphenicol. Following removal of the drugs we further detected clear differences in expression of both mtDNA-encoded genes and nuclear transcription factors that control mitochondrial biogenesis, suggesting that the cells possess different compensatory mechanisms to recover from drug-induced mitochondrial dysfunction. Our data reveal new aspects of the interplay between mitochondrial retrograde signaling and the expression of nuclear regulators of mitochondrial biogenesis, a process with direct relevance to mitochondrial diseases and chloramphenicol toxicity in humans. -- Highlights: ► Cells respond to certain environmental toxins by increasing mitochondrial biogenesis. ► We investigated the effect of Chloramphenicol and EtBr in primary human fibroblasts. ► Inhibiting mitochondrial protein synthesis or DNA replication elicit different effects. ► We provide novel insights into the cellular responses toxins and antibiotics.

  8. The effect of ethidium bromide and chloramphenicol on mitochondrial biogenesis in primary human fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Kao, Li-Pin; Ovchinnikov, Dmitry; Wolvetang, Ernst, E-mail: e.wolvetang@uq.edu.au

    2012-05-15

    The expression of mitochondrial components is controlled by an intricate interplay between nuclear transcription factors and retrograde signaling from mitochondria. The role of mitochondrial DNA (mtDNA) and mtDNA-encoded proteins in mitochondrial biogenesis is, however, poorly understood and thus far has mainly been studied in transformed cell lines. We treated primary human fibroblasts with ethidium bromide (EtBr) or chloramphenicol for six weeks to inhibit mtDNA replication or mitochondrial protein synthesis, respectively, and investigated how the cells recovered from these insults two weeks after removal of the drugs. Although cellular growth and mitochondrial gene expression were severely impaired after both inhibitor treatments we observed marked differences in mitochondrial structure, membrane potential, glycolysis, gene expression, and redox status between fibroblasts treated with EtBr and chloramphenicol. Following removal of the drugs we further detected clear differences in expression of both mtDNA-encoded genes and nuclear transcription factors that control mitochondrial biogenesis, suggesting that the cells possess different compensatory mechanisms to recover from drug-induced mitochondrial dysfunction. Our data reveal new aspects of the interplay between mitochondrial retrograde signaling and the expression of nuclear regulators of mitochondrial biogenesis, a process with direct relevance to mitochondrial diseases and chloramphenicol toxicity in humans. -- Highlights: ► Cells respond to certain environmental toxins by increasing mitochondrial biogenesis. ► We investigated the effect of Chloramphenicol and EtBr in primary human fibroblasts. ► Inhibiting mitochondrial protein synthesis or DNA replication elicit different effects. ► We provide novel insights into the cellular responses toxins and antibiotics.

  9. Study of molecular complexation of glycyrrhizic acid with chloramphenicol by electrospray ionization mass spectrometry

    OpenAIRE

    Vetrova, Elena V.; Lekar, Anna V.; Filonova, Olga V.; Borisenko, Sergey N.; Maksimenko, Elena V.; Borisenko, Nikolay I.

    2015-01-01

    Context: Glycyrrhizic acid (GA) is a triterpene glycoside representing the main active component of licorice root extract obtained from plants of the Glycyrrhiza glabra L. and widely used as a complex-forming agent for the synthesis of new transport forms of the well-known drugs. Aims: For the first time, the complexation of GA with chloramphenicol antibiotic (ChlA) was investigated by electrospray ionization mass spectrometry (ESI MS). Subjects and Methods: ESI MS was utilized in order to de...

  10. Flow-Injection Preconcentration of Chloramphenicol Using Molecularly Imprinted Polymer for HPLC Determination in Environmental Samples

    OpenAIRE

    Marek Trojanowicz; Ewa Poboży; Damian Kowalski

    2011-01-01

    The residue of antibiotic chloramphenicol (CAP) is important issue for food quality control and also for the environmental monitoring. It is banned for use in food-producing animals and has very limited use in human medicine, because of its severe impact on human health. Determination of trace level of CAP in environmental samples requires a very sensitive analytical method and efficient preconcentration procedure. CAP can be efficiently preconcentrated in flow-injection system using flow-thr...

  11. An Electrochemical Impedimetric Aptasensing Platform for Sensitive and Selective Detection of Small Molecules Such as Chloramphenicol

    OpenAIRE

    Sanaz Pilehvar; Tarryn Dierckx; Ronny Blust; Tom Breugelmans; Karolien De Wael

    2014-01-01

    We report on the aptadetection of chloramphenicol (CAP) using electrochemical impedance spectroscopy. The detection principle is based on the changes of the interfacial properties of the electrode after the interaction of the ssDNA aptamers with the target molecules. The electrode surface is partially blocked due to the formation of the aptamer-CAP complex, resulting in an increase of the interfacial electron-transfer resistance of the redox probe detected by electrochemical impedance spectr...

  12. Assessment of Commutability for Candidate Certified Reference Material ERM-BB130 "Chloramphenicol in Pork"

    OpenAIRE

    Zeleny, Reinhard; EMTEBORG Per; Schimmel, Heinz

    2010-01-01

    Chloramphenicol (CAP), an effective antibiotic against many microorganisms, is meanwhile banned in the EU for treatment of food-producing animals due to adverse health effects. The Institute for Reference Materials and Measurements (IRMM) is currently developing a certified reference material (CRM) for CAP in pork, intended for validation and method performance verifications of analytical methods. The material will be certified using liquid chromatography tandem mass spectrometry (LC-MS/MS) a...

  13. Identification and evaluation of radiolysis products of irradiated chloramphenicol by HPLC-MS and HPLC-DAD

    International Nuclear Information System (INIS)

    The radiolysis products of chloramphenicol under γ-radiation sterilization were investigated systematically in the present study. Eight main radiolysis products were identified and quantified by HPLC-MS and HPLC-DAD, including two compounds that have never been reported. The minor radiolysis products were quantified, which shows that they are at the concentration levels below the threshold for identification. Carbon-carbon rupture reaction and oxidation reaction were proposed as the main radiolysis reactions of chloramphenicol powder. The applicability of γ-sterilization for chloramphenicol products was quantitatively evaluated with qualitative and quantitative data and the data were compared to the threshold requirements of international regulations for identification. It was concluded that toxicities of the radiolysis products of chloramphenicol produced by γ-radiation sterilization can be neglected, the radiolysis products are safe for human health from chemical view. (author)

  14. Detection of Chloramphenicol Resistance Genes (cat in Clinical Isolates of Pseudomonas aeruginosa with Polymerase Chain Reaction Method

    Directory of Open Access Journals (Sweden)

    Tiana Milanda

    2014-12-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic Gram negative bacteria, which may cause infection in eyes, ears, skin, bones, central nervous system, gastrointestinal tract, circulatory system, heart, respiratory system, and urinary tract. Recently, chloramphenicol is no longer used as the main option of the therapy due of its resistance case. The aim of this research was to detect the presence of gene which is responsible to chloramphenicol resistance in clinical isolates of P.aeruginosa. These bacteria isolated from pus of external otitis patients in Hasan Sadikin Hospital in Bandung City. Polymerase Chain Reaction (PCR method (colony-PCR and DNA-PCR were performed to detect this resistance gene. Electropherogram from PCR products showed that the chloramphenicol resistance in clinical isolates of P. aeruginosa was caused by cat gene (317 bp. Based on this research, cat gene may be used to detect the chloramphenicol resistance in patients with external ostitis.

  15. Determination of assay and impurities of gamma irradiated chloramphenicol in eye ointment

    International Nuclear Information System (INIS)

    A sample preparation method was developed to isolate chloramphenicol and its radiolytic products from an oily ointment base. The isolation method suspended the eye ointment in n-hexane at 45 deg C, and isolated the target compounds as residue by centrifugation. It was found that the main element to ensure a satisfactory isolation was keeping the sample solution at 45 deg C during sample preparation. Linearity, precision, accuracy and suitability of the method were confirmed valid for both assay and impurity tests. This isolation method was ideal for assay, unique for extraction of unexpected and complex radiolysis products, and had a number of advantages compared to the pretreatment methods described in the United States Pharmacopoeia and British Pharmacopoeia, in terms of accuracy, precision, and easy handling. The effect of γ-irradiation on chloramphenicol eye ointment was studied by HPLC-DAD, after applying the developed sample preparation method. The present assay and impurity test methods with HPLC-DAD were confirmed to be suitable for irradiated chloramphenicol in eye ointment. (author)

  16. Effects of Garlic (Alliumsativum) and chloramphenicol on growth performance, physiological parameters and survival of Nile tilapia (Oreochromis niloticus)

    OpenAIRE

    Shalaby, A. M.; Y. A. Khattab; Abdel Rahman, A. M. [امينة عبد الرحمن

    2006-01-01

    We studied and compared the effects of chloramphenicol antibiotic and garlic (Allium sativum), used as immunostimulants and growth promoters, on some physiological parameters, growth performance, survival rate, and bacteriological characteristics of Nile tilapia (Oreochromis niloticus). Fish (7±1g/fish) were assigned to eight treatments, with three replicates each. Treatment groups had a different level of Allium sativum (10, 20, 30, and 40g/kg diet) and chloramphenicol (15, 30, and 45mg/kg d...

  17. Design and fabrication of an aptasensor for chloramphenicol based on energy transfer of CdTe quantum dots to graphene oxide sheet

    International Nuclear Information System (INIS)

    Detection and quantification of chloramphenicol have played essential roles in the effort to minimize food safety risk. Herein, a sophisticated “turn on” aptasensor based on aptamer–CdTe quantum dots (Apt–QDs) and graphene oxide (GO) was developed for chloramphenicol sensing. In this assay, the fluorescence of CdTe QDs–Apt was efficiently quenched through energy transfer from QDs–Apt to GO, and chloramphenicol was detected by recovering the quenched fluorescence due to specific binding between aptamer and chloramphenicol. The results indicated that the addition of a CdTe QDs-labeled aptamer to a GO solution (250 μg/mL) led to a high quenching efficiency, yielding over 90% fluorescence quenching. Using a series of chloramphenicol concentrations (0.1 to 10 nM) aptasensor provides a limit of detection and limit of quantification at 98 pM and 987 pM, respectively. Linearity of response over chloramphenicol was demonstrated (r > 0.99). Furthermore, the GO-based aptasensor exhibited excellent selectivity toward chloramphenicol compared to other synthetic drugs with similar structures such as thiamphenicol, metronidazole and nitrofurantoin. Good reproducibility and precision (RSD 4.73%, n = 10) of the assay indicates the ability of the aptasensor for routine quantitative trace analysis of chloramphenicol. Our results suggested that the prepared aptasensor was also well qualified for the detection of chloramphenicol in milk with a limit of detection of 0.2 ppb. - Highlights: • Aptasensor based on aptamer–QDs and GO was developed for chloramphenicol sensing. • The fluorescence of QDs–Apt was quenched through energy transfer from QDs to GO. • Chloramphenicol was detected by recovering the quenched fluorescence. • The limit of detection for chloramphenicol was calculated to be 98 pM. • The proposed aptasensor showed high sensitivity, selectivity and precision

  18. Design and fabrication of an aptasensor for chloramphenicol based on energy transfer of CdTe quantum dots to graphene oxide sheet

    Energy Technology Data Exchange (ETDEWEB)

    Alibolandi, Mona; Hadizadeh, Farzin [Biotechnology Research Center, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of); Vajhedin, Fereshteh [Department of Chemistry, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of); Abnous, Khalil, E-mail: Abnouskh@mums.ac.ir [Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of); Ramezani, Mohammad, E-mail: Ramezanim@mums.ac.ir [Nanotechnology Research Center, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of)

    2015-03-01

    Detection and quantification of chloramphenicol have played essential roles in the effort to minimize food safety risk. Herein, a sophisticated “turn on” aptasensor based on aptamer–CdTe quantum dots (Apt–QDs) and graphene oxide (GO) was developed for chloramphenicol sensing. In this assay, the fluorescence of CdTe QDs–Apt was efficiently quenched through energy transfer from QDs–Apt to GO, and chloramphenicol was detected by recovering the quenched fluorescence due to specific binding between aptamer and chloramphenicol. The results indicated that the addition of a CdTe QDs-labeled aptamer to a GO solution (250 μg/mL) led to a high quenching efficiency, yielding over 90% fluorescence quenching. Using a series of chloramphenicol concentrations (0.1 to 10 nM) aptasensor provides a limit of detection and limit of quantification at 98 pM and 987 pM, respectively. Linearity of response over chloramphenicol was demonstrated (r > 0.99). Furthermore, the GO-based aptasensor exhibited excellent selectivity toward chloramphenicol compared to other synthetic drugs with similar structures such as thiamphenicol, metronidazole and nitrofurantoin. Good reproducibility and precision (RSD 4.73%, n = 10) of the assay indicates the ability of the aptasensor for routine quantitative trace analysis of chloramphenicol. Our results suggested that the prepared aptasensor was also well qualified for the detection of chloramphenicol in milk with a limit of detection of 0.2 ppb. - Highlights: • Aptasensor based on aptamer–QDs and GO was developed for chloramphenicol sensing. • The fluorescence of QDs–Apt was quenched through energy transfer from QDs to GO. • Chloramphenicol was detected by recovering the quenched fluorescence. • The limit of detection for chloramphenicol was calculated to be 98 pM. • The proposed aptasensor showed high sensitivity, selectivity and precision.

  19. Rapid Detection of Chloramphenicol Residues in Aquatic Products Using Colloidal Gold Immunochromatographic Assay

    OpenAIRE

    Chennan Zhou; Xueyin Zhang; Xinxin Huang; Xishan Guo; Qiang Cai; Songming Zhu

    2014-01-01

    A colloidal gold immunochromatographic assay (GICA) was developed for rapid detection of chloramphenicol (CAP) residues in aquatic products. A nitrocellulose (NC) membrane was used as the carrier, and the polyclonal CAP antibody was used as the marker protein. The average diameter of as-prepared colloidal gold nanoparticles (AuNPs) was about 20 nm. The optimal pH value of colloidal gold solutions and the amount of the antibody of CAP were 8.0 and 7.2 μg/mL, respectively. The CAP antibody was...

  20. Differential regulation of rat beta-casein-chloramphenicol acetyltransferase fusion gene expression in transgenic mice.

    OpenAIRE

    Lee, K. F.; Atiee, S H; Rosen, J. M.

    1989-01-01

    Previous studies in our laboratory have demonstrated the mammary-specific expression of the entire rat beta-casein gene with 3.5 kilobases (kb) of 5' and 3.0 kb of 3' DNA in transgenic mice (Lee et al., Nucleic Acids Res. 16:1027-1041, 1988). In an attempt to localize sequences that dictate this specificity, lines of transgenic mice carrying two different rat beta-casein promoter-bacterial chloramphenicol acetyltransferase (cat) fusion genes have been established. Twenty and eight lines of tr...

  1. Design and fabrication of an aptasensor for chloramphenicol based on energy transfer of CdTe quantum dots to graphene oxide sheet.

    Science.gov (United States)

    Alibolandi, Mona; Hadizadeh, Farzin; Vajhedin, Fereshteh; Abnous, Khalil; Ramezani, Mohammad

    2015-03-01

    Detection and quantification of chloramphenicol have played essential roles in the effort to minimize food safety risk. Herein, a sophisticated "turn on" aptasensor based on aptamer-CdTe quantum dots (Apt-QDs) and graphene oxide (GO) was developed for chloramphenicol sensing. In this assay, the fluorescence of CdTe QDs-Apt was efficiently quenched through energy transfer from QDs-Apt to GO, and chloramphenicol was detected by recovering the quenched fluorescence due to specific binding between aptamer and chloramphenicol. The results indicated that the addition of a CdTe QDs-labeled aptamer to a GO solution (250μg/mL) led to a high quenching efficiency, yielding over 90% fluorescence quenching. Using a series of chloramphenicol concentrations (0.1 to 10nM) aptasensor provides a limit of detection and limit of quantification at 98pM and 987pM, respectively. Linearity of response over chloramphenicol was demonstrated (r>0.99). Furthermore, the GO-based aptasensor exhibited excellent selectivity toward chloramphenicol compared to other synthetic drugs with similar structures such as thiamphenicol, metronidazole and nitrofurantoin. Good reproducibility and precision (RSD 4.73%, n=10) of the assay indicates the ability of the aptasensor for routine quantitative trace analysis of chloramphenicol. Our results suggested that the prepared aptasensor was also well qualified for the detection of chloramphenicol in milk with a limit of detection of 0.2ppb. PMID:25579964

  2. A novel colorimetric sandwich aptasensor based on an indirect competitive enzyme-free method for ultrasensitive detection of chloramphenicol.

    Science.gov (United States)

    Abnous, Khalil; Danesh, Noor Mohammad; Ramezani, Mohammad; Emrani, Ahmad Sarreshtehdar; Taghdisi, Seyed Mohammad

    2016-04-15

    Analytical methods for detection and quantitation of chloramphenicol in blood serum and foodstuffs arse highly in demand. In this study, a colorimetric sandwich aptamer-based sensor (aptasensor) was fabricated for sensitive and selective detection of chloramphenicol, based on an indirect competitive enzyme-free assay using gold nanoparticles (AuNPs), biotin and streptavidin. The designed aptasensor acquires characteristics of AuNPs, including large surface area and unique optical properties, and strong interaction of biotin with streptavidin. In the absence of chloramphenicol, the sandwich structure of aptasensor forms, leading to the observation of sharp red color. In the presence of target, functionalized AuNPs could not bind to 96-well plates, resulting in a faint red color. The fabricated colorimetric aptasensor exhibited high selectivity toward chloramphenicol with a limit of detection as low as 451 pM. Moreover, the developed colorimetric aptasensor was successfully used to detect chloramphenicol in milk and serum with LODs of 697 and 601 pM, respectively. PMID:26599477

  3. Synthesis and evaluation of chloramphenicol homodimers: molecular target, antimicrobial activity, and toxicity against human cells.

    Directory of Open Access Journals (Sweden)

    Ourania N Kostopoulou

    Full Text Available As fight against antibiotic resistance must be strengthened, improving old drugs that have fallen in reduced clinical use because of toxic side effects and/or frequently reported resistance, like chloramphenicol (CAM, is of special interest. Chloramphenicol (CAM, a prototypical wide-spectrum antibiotic has been shown to obstruct protein synthesis via binding to the bacterial ribosome. In this study we sought to identify features intensifying the bacteriostatic action of CAM. Accordingly, we synthesized a series of CAM-dimers with various linker lengths and functionalities and compared their efficiency in inhibiting peptide-bond formation in an Escherichia coli cell-free system. Several CAM-dimers exhibited higher activity, when compared to CAM. The most potent of them, compound 5, containing two CAM bases conjugated via a dicarboxyl aromatic linker of six successive carbon-bonds, was found to simultaneously bind both the ribosomal catalytic center and the exit-tunnel, thus revealing a second, kinetically cryptic binding site for CAM. Compared to CAM, compound 5 exhibited comparable antibacterial activity against MRSA or wild-type strains of Staphylococcus aureus, Enterococcus faecium and E. coli, but intriguingly superior activity against some CAM-resistant E. coli and Pseudomonas aeruginosa strains. Furthermore, it was almost twice as active in inhibiting the growth of T-leukemic cells, without affecting the viability of normal human lymphocytes. The observed effects were rationalized by footprinting tests, crosslinking analysis, and MD-simulations.

  4. Azithromycin, fluoroquinolone and chloramphenicol resistance of non-chlamydia conjunctival bacteria in rural community of Ethiopia

    Directory of Open Access Journals (Sweden)

    Bayeh Abera

    2014-01-01

    Full Text Available Aim: To determine profiles of non-chlamydia conjunctival bacteria and their antimicrobial susceptibility from adults who underwent trachomatous trichiasis surgery in rural areas of Ethiopia. Materials and Methods: A cross-sectional study was conducted in rural districts in West Gojjam administrative zone. Conjunctival swabs were collected during surgery and transported using Stuart transport broth (Oxoid, UK. Antibiotic susceptibility of conjunctival isolates was determined using the Kirby-Bauer disc-diffusion method. Results: Non-chlamydia pathogenic bacteria were recovered from conjunctiva of 438 (31% participants before treatment. The isolated conjunctival bacteria were Staphylococcus aureus, coagulase-negative Staphylococci, Streptococcus group (A, C, F and G, Enterococci, Streptococcus pneumoniae, Moraxella spp., Escherichia coli, Citrobacter spp., Proteus spp., Klebsiella spp., Pseudomonas spp. and Enterobacter spp. Overall, resistance rates of 57.8% to azithromycin and 68.5% to chloramphenicol were found. However, 86-94.4% sensitivity was demonstrated to ciprofloxacin and norfloxacin. Moderate sensitivity rates (61.8-78.4% were observed to ceftriaxone, tetracycline and cotrimoxazole. Conclusion: Fluoroquinolones that have activity against the majority of bacterial isolates were potent at in vitro. However, unacceptably high levels of resistance to azithromycin and chloramphenicol in rural community indicated a need for further study and antimicrobial resistance surveillance.

  5. Synthesis and Evaluation of Chloramphenicol Homodimers: Molecular Target, Antimicrobial Activity, and Toxicity against Human Cells

    Science.gov (United States)

    Kostopoulou, Ourania N.; Magoulas, George E.; Papadopoulos, Georgios E.; Mouzaki, Athanasia; Dinos, George P.; Papaioannou, Dionissios; Kalpaxis, Dimitrios L.

    2015-01-01

    As fight against antibiotic resistance must be strengthened, improving old drugs that have fallen in reduced clinical use because of toxic side effects and/or frequently reported resistance, like chloramphenicol (CAM), is of special interest. Chloramphenicol (CAM), a prototypical wide-spectrum antibiotic has been shown to obstruct protein synthesis via binding to the bacterial ribosome. In this study we sought to identify features intensifying the bacteriostatic action of CAM. Accordingly, we synthesized a series of CAM-dimers with various linker lengths and functionalities and compared their efficiency in inhibiting peptide-bond formation in an Escherichia coli cell-free system. Several CAM-dimers exhibited higher activity, when compared to CAM. The most potent of them, compound 5, containing two CAM bases conjugated via a dicarboxyl aromatic linker of six successive carbon-bonds, was found to simultaneously bind both the ribosomal catalytic center and the exit-tunnel, thus revealing a second, kinetically cryptic binding site for CAM. Compared to CAM, compound 5 exhibited comparable antibacterial activity against MRSA or wild-type strains of Staphylococcus aureus, Enterococcus faecium and E. coli, but intriguingly superior activity against some CAM-resistant E. coli and Pseudomonas aeruginosa strains. Furthermore, it was almost twice as active in inhibiting the growth of T-leukemic cells, without affecting the viability of normal human lymphocytes. The observed effects were rationalized by footprinting tests, crosslinking analysis, and MD-simulations. PMID:26267355

  6. [Construction and characterization of a brucella suis S2 strain with a chloramphenicol resistance marker].

    Science.gov (United States)

    Mao, Kai-Rong; Ding, Jia-Bo; Cheng, Jun-Sheng; Jiang, Yu-Wen; Yao, Wen-Sheng

    2007-12-01

    Vaccination has not been used widely because of the interference in the discrimination between infected and vaccinated animals in immune-screening procedures. In the present study, chloramphenicol resistance gene (Cm(r)) was cloned into the genomic DNA of brucella suis S2 strain by homologous recombination with knocking out the WbkC gene, and obtained the recombinant rS2-WbkC. Further study confirmed that rS2-WbkC was conversed into rough-phenotype form smooth-phenotype. The recombinant keeps the ability to chloramphenicol resistance after 25 passages in tryptic soy agar (TSA). Mice tests showed rS2-WbkC offered similar protection to S2 strain, but more safe than S2. Serum collected form rS2-WbkC immunized mice could be easily distinguished from antiserum produced by smooth-phenotype brucella abortus. In view of these result, rS2-WbkC is a promising candidate for vaccine strain. PMID:18271249

  7. Stability-indicating liquid Chromatographic assaymethod for Opthalmic solutions containing combination of Dexamethasone and Chloramphenicol

    International Nuclear Information System (INIS)

    A selective high-performance chromatographic procedure for the stability monitoring of ophthalmic solutions containing a combination of dexamethasone and chloramphenicolis demonstrated. The separation of the active components and the degradation product of chloramphenicol (1-amino-1-(4-nitrophenyl)-propane-1, 3diol) was achieved on a u-Bondapack C-18 column ( 5 um, 300 mm x 3.9 mm) maintained at ambient temperature (15-20C) by utilizing a mobile phase consisting acidified water (5% actified water with glacial acetic acid ) : acetonitrile : triethyl amine 700 : 300 : 2and pH was adjusted to 5.0 by using 10 M Na OH. The flow rate was 1.5 ml min-1; and elutes were followed with UV-detection at 254 nm. Complete resolution of dexamethasone, chloramphenicol and its hydrolytic product could be attained. The sensitivity, accuracy and specificity were tested. The method was successfully applied in post-marketing stability of the commercial batches of ophthalmic solutions. (author)

  8. Determination of nitrofuran and chloramphenicol residues by high resolution mass spectrometry versus tandem quadrupole mass spectrometry.

    Science.gov (United States)

    Kaufmann, A; Butcher, P; Maden, K; Walker, S; Widmer, M

    2015-03-01

    An ultra-high performance liquid chromatography based method, coupled to high resolution mass spectrometry (UHPLC-HRMS), was developed to permit the detection and quantification of various nitrofuran and chloramphenicol residues in a number of animal based food products. This method is based on the hydrolysis of covalently bound metabolites and derivatization with 2-nitrobenzaldehyde. Clean-up is achieved by a liquid/liquid and a reversed phase/solid phase extraction. Not only are the four conventional nitrofurans (nitrofurantoin, furazolidone, nitrofurazone and furaltadone) detected, but also nifursol, nitrovin and nifuroxazide. Furthermore, an underivatizable nitrofuran (nifurpirinol) and another banned drug (chloramphenicol) can be quantified as well. The compounds are detected in the form of their precursor ions, [M+H](+) and [M-H](-), respectively. The mass resolving power of 70,000 FWHM, and the applied mass window ensure sufficient selectivity and sensitivity. Confirmation is obtained by monitoring the HRMS resolved product ions which were derived from the unit-mass resolved precursor ions. The multiplexing capability of the utilized Orbitrap instrument provides not only highly selective, but also sensitive confirmatory signals. This method has been validated according to the CD 2002/657/EC for the following matrices: muscle, liver, kidney, fish, honey, eggs and milk. PMID:25682427

  9. Effect of ciprofloxacin and chloramphenicol on humoral immune response elicited by bovine albumin encapsulated in niosomes

    Institute of Scientific and Technical Information of China (English)

    MADANJitender; KAUSHIKDinesh; SARDANASatish; MISHRADn

    2007-01-01

    The aim is to evaluate the effect of ciprofloxacin and chloramphenicol on anti-BSA antibody production triggered by bovine albumin encapsulated in non-ionic surfactant vesicle, niosomes. Reverse phase evaporation method was adopted to entrap the antigen in colloidal carrier composed of Span 80 and Span 85 followed by simultaneous characterization for particle size, entrapment efficiency and in vitro release. The protein content was determined by Bradford method using UV Visible Spectrophotometer at 595 nm. Humoral immune response was measured in terms of systemic IgG antibody titre by ELISA method. Experimental data indicated that 7∶3 molar ratio of Span 80 and cholesterol based niosomal formulation possessed maximum (39.8±2.9)% of soluble protein.Ciprofloxacin markedly (P<0.05) decreased the antibody titre. In contrast, chloramphenicol did not reduce the antibody titre significantly in comparison to control group (P>0.05). It is necessary to explore the effect of a vaccine antigen when a candidate is medicated with a therapeutic agent, which might help in programming a new drug management and vaccination programme.

  10. Characterization and Uncertainty Assessment of a Certified Reference Material of Chloramphenicol in Methanol (GBW(E)082557)

    Science.gov (United States)

    Zhou, Jian; Song, Yinqing; Wang, Tongtong

    2016-01-01

    Prior to preparation of CRM candidate of chloramphenicol in methanol with a concentration of 100 mg/L, two independent methods including mass balance (MB) and quantitative nuclear magnetic resonance (qNMR) were employed to precisely measure the mass fraction of pure chloramphenicol materials. The mass fraction was assigned to be 99.8% with uncertainty of 0.3%. Homogeneity testing and stability study of chloramphenicol in methanol were examined by using high performance liquid chromatography. Additionally, the uncertainties originating from the process of CRM development were comprehensively evaluated. The experimental results indicate that the property value of this CRM is homogeneous and stable at 4°C for at least six months. The new CRM (GBW(E)082557) can be applicable to calibration of instrument and assurance of accuracy and comparability of results in routine measurement. PMID:27493666

  11. Effect of kinetin and chloramphenicol on chlorophyll synthesis and chloroplast development in detached lupin cotyledons under low light intensity

    Directory of Open Access Journals (Sweden)

    Fortunat Młodzianowski

    2015-05-01

    Full Text Available Chlorophyll synthesis in detached lupin cotyledons under low light intensity was stimulated by kinetin at 20 mg/l and inhibited by chloramphenicol at 50 mg/1. Kinetin not only conteracted the inhibitory effect of chloramphenicol, but stimulated1 the chlorophyll syntesis to a greater level than in the control material. Kinetin accelerated the starch degradation and the development of chloroplast; its prolonged, action, however, produced some abnormalities, such as an excessive growth of plastids resulting in some cases in bursting of their envelopes, the formation and release f r om plastids of numerous membrane - bound bodies and the accumulation in released and swollen thylakoids of electron - dense substance. In the presence of chloramphenicol, some disturbances in structure of the stroma thylakoids and the appearance of vesicular structures in the stroma and the enlargement of grana and swelling of their thylakoids were observed. Kinetin prevented some of these abnormalities.

  12. Characterization and Uncertainty Assessment of a Certified Reference Material of Chloramphenicol in Methanol (GBW(E)082557).

    Science.gov (United States)

    Yang, Mengrui; Wang, Min; Zhou, Jian; Song, Yinqing; Wang, Tongtong

    2016-01-01

    Prior to preparation of CRM candidate of chloramphenicol in methanol with a concentration of 100 mg/L, two independent methods including mass balance (MB) and quantitative nuclear magnetic resonance (qNMR) were employed to precisely measure the mass fraction of pure chloramphenicol materials. The mass fraction was assigned to be 99.8% with uncertainty of 0.3%. Homogeneity testing and stability study of chloramphenicol in methanol were examined by using high performance liquid chromatography. Additionally, the uncertainties originating from the process of CRM development were comprehensively evaluated. The experimental results indicate that the property value of this CRM is homogeneous and stable at 4°C for at least six months. The new CRM (GBW(E)082557) can be applicable to calibration of instrument and assurance of accuracy and comparability of results in routine measurement. PMID:27493666

  13. Final report on key comparison CCQM-K81: Chloramphenicol in pig muscle

    Science.gov (United States)

    Polzer, Joachim; Henrion, Andre; Gowik, Petra

    2013-01-01

    Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM-K81 'Chloramphenicol in pig muscle', was coordinated by BVL and PTB in 2009/2010. Six NMIs/DIs participated in this comparison. Chloramphenicol (CAP) is an effective broad-spectrum antibiotic which can in principle be used for the treatment of humans and animals. Its use for the treatment of food-producing animals is, however, forbidden worldwide in many countries due to potential severe side effects. The key comparison was the follow-up to the successful pilot study 'CCQM-P90: chloramphenicol in milk'. With this key comparison it was intended to demonstrate the capability of NMIs/DIs to analyse traces of CAP in food at concentration levels resulting from legal requirements for food control. Additionally, the quality of this kind of analysis with respect to compliance with legal requirements for food control methods and the international comparability of measurements should be evaluated in general. The study was classified as a 'track C' study (studies in emerging areas of global interest). For the study incurred lyophilised pig muscle material containing CAP (at a mass-fraction level around the maximum allowable level for import for a number of countries) has been produced as a candidate reference material by BVL and IRMM (Institute for Reference Materials and Measurements, JRC of the European Commission). Animal treatment and slaughtering of the animal to gain incurred muscle material as well as pre-testing of the CAP content was done at the BVL. The IRMM did further processing of the material and testing of homogeneity and stability. Participants were invited to assign the mass fraction of free CAP in the comparison sample. CCQM-K81 demonstrated successfully the capability of the participating laboratories to assign chloramphenicol values in tissue down to residue levels of around 0.3 ng/g (referring to the

  14. A structural study of the interaction between the Dr haemagglutinin DraE and derivatives of chloramphenicol

    International Nuclear Information System (INIS)

    The structures of two Dr adhesin (DraE) complexes with chloramphenicol derivatives, namely chloramphenicol succinate and bromamphenicol, have been solved. The structures reveal important functional groups for small-molecule binding and imply possible modifications to the molecule that would permit a more wide-ranging interaction without the toxic side effects associated with chloramphenicol. Dr adhesins are expressed on the surface of uropathogenic and diffusely adherent strains of Escherichia coli. The major adhesin subunit (DraE/AfaE) of these organelles mediates attachment of the bacterium to the surface of the host cell and possibly intracellular invasion through its recognition of the complement regulator decay-accelerating factor (DAF) and/or members of the carcinoembryonic antigen (CEA) family. The adhesin subunit of the Dr haemagglutinin, a Dr-family member, additionally binds type IV collagen and is inhibited in all its receptor interactions by the antibiotic chloramphenicol (CLM). In this study, previous structural work is built upon by reporting the X-ray structures of DraE bound to two chloramphenicol derivatives: chloramphenicol succinate (CLS) and bromamphenicol (BRM). The CLS structure demonstrates that acylation of the 3-hydroxyl group of CLM with succinyl does not significantly perturb the mode of binding, while the BRM structure implies that the binding pocket is able to accommodate bulkier substituents on the N-acyl group. It is concluded that modifications of the 3@@hydroxyl group would generate a potent Dr haemagglutinin inhibitor that would not cause the toxic side effects that are associated with the normal bacteriostatic activity of CLM

  15. The effect of nalidixic acid, rifampicin and chloramphenicol on the synthesis of phospholipase C in Bacillus cereus

    International Nuclear Information System (INIS)

    The effect of nalidixic acid, rifampicin and chloramphenicol on the synthesis of phospholipase C (EC 3.1.4.3) has been studied in washed Bacillus cereus cells resuspended in nutrient broth. In the absence of inhibitors, the synthesis showed a biphasic pattern. No synthesis or release of enzyme was found in the presence of chloramphenicol. When rifampicin was added, phospholipase C synthesis for 10-15 min. Nalidixic acid, at concentrations which inhibited DNA synthesis completely, permitted the synthesis of phospholipase C at the same rate and for a similar length of time as rifampicin. (author)

  16. Gamma-ray induced ageing mutants of Neurospora crassa: response to some antioxidants and chloramphenicol

    International Nuclear Information System (INIS)

    Several ageing (early senescent) mutants of N. crassa were induced by subjecting the conidia to gamma irradiation. At a culture age of 15 days the conidial viability of the mutants ranged from 0-28per cent, but in case of their wild-type (EM A) it was 95per cent. The effect of antioxidants and free radical scavengers such as vitamin E, vitamin C and sodium selenite on extensional growth behaviour, replication potentialities, biomass production capacity and accumulation of lipoidal substances by these strains were investigated. Studies were also made to see the effect of chloramphenicol; and concentration of malondialdehyde in the culture filtrates was measured. The results show that more biological processes than one are involved in the cellular ageing phenomenon and increased free readical reaction is not the sole factor. (author)

  17. An Improved Electrochemical Aptasensor for Chloramphenicol Detection Based on Aptamer Incorporated Gelatine

    Directory of Open Access Journals (Sweden)

    Ezat Hamidi-Asl

    2015-03-01

    Full Text Available Because of the biocompatible properties of gelatine and the good affinity of aptamers for their targets, the combination of aptamer and gelatine type B is reported as promising for the development of biosensing devices. Here, an aptamer for chloramphenicol (CAP is mixed with different types of gelatine and dropped on the surface of disposable gold screen printed electrodes. The signal of the CAP reduction is investigated using differential pulse voltammetry. The diagnostic performance of the sensor is described and a detection limit of 1.83 × 10−10 M is found. The selectivity and the stability of the aptasensor are studied and compared to those of other CAP sensors described in literature.

  18. An Electrochemical Impedimetric Aptasensing Platform for Sensitive and Selective Detection of Small Molecules Such as Chloramphenicol

    Directory of Open Access Journals (Sweden)

    Sanaz Pilehvar

    2014-07-01

    Full Text Available We report on the aptadetection of chloramphenicol (CAP using electrochemical impedance spectroscopy. The detection principle is based on the changes of the interfacial properties of the electrode after the interaction of the ssDNA aptamers with the target molecules. The electrode surface is partially blocked due to the formation of the aptamer-CAP complex, resulting in an increase of the interfacial electron-transfer resistance of the redox probe detected by electrochemical impedance spectroscopy or cyclic voltammetry. We observed that the ratio of polarization resistance had a linear relationship with the concentrations of CAP in the range of 1.76–127 nM, and a detection limit of 1.76 nM was obtained. The covalent binding of CAP-aptamer on the electrode surface combined with the unique properties of aptamers and impedimetric transduction leads to the development of a stable and sensitive electrochemical aptasensor for CAP.

  19. An electrochemical impedimetric aptasensing platform for sensitive and selective detection of small molecules such as chloramphenicol.

    Science.gov (United States)

    Pilehvar, Sanaz; Dierckx, Tarryn; Blust, Ronny; Breugelmans, Tom; De Wael, Karolien

    2014-01-01

    We report on the aptadetection of chloramphenicol (CAP) using electrochemical impedance spectroscopy. The detection principle is based on the changes of the interfacial properties of the electrode after the interaction of the ssDNA aptamers with the target molecules. The electrode surface is partially blocked due to the formation of the aptamer-CAP complex, resulting in an increase of the interfacial electron-transfer resistance of the redox probe detected by electrochemical impedance spectroscopy or cyclic voltammetry. We observed that the ratio of polarization resistance had a linear relationship with the concentrations of CAP in the range of 1.76-127 nM, and a detection limit of 1.76 nM was obtained. The covalent binding of CAP-aptamer on the electrode surface combined with the unique properties of aptamers and impedimetric transduction leads to the development of a stable and sensitive electrochemical aptasensor for CAP. PMID:25004156

  20. Construction and Use of a Replication-Competent Human Immunodeficiency Virus (HIV-1) that Expresses the Chloramphenicol Acetyltransferase Enzyme

    Science.gov (United States)

    Terwilliger, E. F.; Godin, B.; Sodroski, J. G.; Haseltine, W. A.

    1989-05-01

    The construction and properties of an infectious human immunodeficiency virus (HIV) that expresses the bacterial gene chloramphenicol acetyltransferase are described. This virus can be used in vitro to screen for drugs that inhibit HIV infection. The marked virus may also be used to trace the routes of infection from the site of inoculation in animal experiments.

  1. Oxidative DNA damage induced by metabolites of chloramphenicol, an antibiotic drug.

    Science.gov (United States)

    Ohnishi, Shiho; Murata, Mariko; Ida, Naoyuki; Oikawa, Shinji; Kawanishi, Shosuke

    2015-01-01

    Chloramphenicol (CAP) was an old antimicrobial agent. However, the use of CAP is limited because of its harmful side effects, such as leukemia. The molecular mechanism through which CAP has been strongly correlated with leukemogenesis is still unclear. To elucidate the mechanism of genotoxicity, we examined DNA damage by CAP and its metabolites, nitroso-CAP (CAP-NO), N-hydroxy-CAP (CAP-NHOH), using isolated DNA. CAP-NHOH have the ability of DNA damage including 8-oxo-7,8-dihydro-2'-deoxyguanosine formation in the presence of Cu(II), which was greatly enhanced by the addition of an endogenous reductant NADH. CAP-NO caused DNA damage in the presence of Cu(II), only when reduced by NADH. NADH can non-enzymatically reduce the nitroso form to hydronitroxide radicals, resulting in enhanced generation of reactive oxygen species followed by DNA damage through the redox cycle. Furthermore, we also studied the site specificity of base lesions in DNA treated with piperidine or formamidopyrimidine-DNA glycosylase, using (32)P-5'-end-labeled DNA fragments obtained from the human tumor suppressor gene. CAP metabolites preferentially caused double base lesion, the G and C of the ACG sequence complementary to codon 273 of the p53 gene, in the presence of NADH and Cu(II). Therefore, we conclude that oxidative double base lesion may play a role in carcinogenicity of CAP. PMID:25971446

  2. The changes in pharmacokinetics and conjugation of chloramphenicol in irradiated rats

    International Nuclear Information System (INIS)

    In the serum and the liver of rats levels of chloramphenicol (CAP) following its i.v. administration (200mg/kg) in the control groups and in the rats irradiated with whole-body air exposure to 500 R were determined with spectrophotometric methods. The CAP-levels in the serum increased in the group of rats 3 days after irradiation, but only during the 1st hour. At later time intervals the values were lower than in the controls. This decrease at the 60th min is striking even in the groups 6 and 9 days after exposure. Free CAP in the liver of rats irradiated 6 and 9 days before was lower at interval 30min after CAP-administration, but the group irradiated 9 days before was unaltered. However, 120min after CAP-administration the values of free CAP decreased at all intervals investigated following the irradiation. The levels of conjugated CAP in the liver of the rats 3 and 6 days after exposure were lower than in controls in both intervals after drug administration; but in rats 9 days after irradiation they increased. Our results indicate that the kinetics of CAP is altered and corresponding changes in its conjugation are effected under the condition of acute radiation syndrome. (orig.)

  3. Electrocatalytic determination of chloramphenicol based on molybdenum disulfide nanosheets and self-doped polyaniline.

    Science.gov (United States)

    Yang, Ruirui; Zhao, Jinlong; Chen, Meijing; Yang, Tao; Luo, Shizhong; Jiao, Kui

    2015-01-01

    In this paper, a novel molybdenum disulfide (MoS2) intercalated by self-doped polyaniline (SPAN) via ultrasonic exfoliating method was prepared to show outstanding conductivity and synergistic electrocatalytic activity using chloramphenicol (CAP) as a case. In the ultrasonic process, due to the strong π-π(*) stacking interaction and electrostatic repulsion, the negatively charged SPAN served as an intercalator to result in few-layers MoS2 nanosheets, which were exfoliated from bulk MoS2. This nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy and differential pulse voltammetry. The obtained nanocomposite owns large conjugated structure and rich negative charge, which can improve the adsorption of conjugate structured CAP with the detection range from 0.1 to 1000 μmol L(-1). The results also showed that the electrocatalytic responses were further affected by the mass ratio of SPAN-MoS2 and the ultrasonication time. Our electrocatalytic platform could be further applied in the adsorption and detection of other positively charged biomolecules or aromatic molecules. PMID:25281149

  4. Application of the chloramphenicol acetyltransferase (CAT) diffusion assay to transgenic plant tissues.

    Science.gov (United States)

    Peach, C; Velten, J

    1992-02-01

    Chloramphenicol acetyltransferase (CAT) activity was quantified in crude extracts from tobacco callus tissues using a modification of a previously reported diffusion assay. We describe here the alterations necessary in applying this rapid and simple assay procedure to plant materials. Due to the high concentration of nonspecific oxidases present in most plant tissues, some type of protective agent is required to maintain enzyme activity. We have tested beta-mercaptoethanol, cysteine, dithiothreitol, ascorbic acid and polyvinyl pyrrolidone as protective agents within the initial extraction buffer. We also investigated the effect of heat (60 degrees C, 10 min) and 5 mM EDTA on CAT activity. The highest CAT activity was obtained using 5 mM cysteine plus 5 mM EDTA in 40 mM Tris-HCl (pH 7.8) as the initial extraction buffer followed by a heat treatment. Using this buffer, CAT activity was stable on ice for more than two hours. In our hands, total acetyl-coenzyme A concentration within the assay mixture was found to be saturating at 250 microM and the Km determined to be 100 microM. Assays performed using the same crude plant extract indicate that 1) duplicate assays show less than 1.5% variation in activities and 2) CAT activity increases linearly with respect to volume of extract used. PMID:1616705

  5. Fluorescent aptasensor for chloramphenicol detection using DIL-encapsulated liposome as nanotracer.

    Science.gov (United States)

    Miao, Yang-Bao; Ren, Hong-Xia; Gan, Ning; Cao, Yuting; Li, Tianhua; Chen, Yijin

    2016-07-15

    A novel fluorescence aptasensor was successfully developed to respond to chloramphenicol (CAP) in food based on magnetic aptamer-liposome vesicle probe. In order to fabricate it, aptamer labeled on functionalized magnetic beads (MB) was firstly employed as capture adsorbent (MB-Apt), then SSB (single-stranded DNA binding protein) and DIL (1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanineperchlorate) coimmobilized liposomes (SSB/DIL-Lip) was employed as vesicle signal tracer. The composite vesicle probe is formed between SSB/DIL-Lip and MB-Apt based on SSB's specific recognition towards aptamer on vesicle signal tracer. Upon the vesicle probe solution reacted with CAP, the aptamer on the magnetic beads preferentially bounded with CAP, and then released SSB/DIL-Lip vesicle signal tracer in the supernatant after magnetic separation. The released tracer can emit fluorescence which was correspondence with the concentration of the analyte. At the optimum conditions, the aptasensor exhibited a good linear response for CAP detection in the range of 0.003-10nM with a detection limit of 1pM. Importantly, the methodology was further validated for analyzing CAP in fish samples with consistent results obtained by ELISA kit, thus providing a promising approach for quantitative monitoring of CAP and significant anti-interference ability in food safety. PMID:27015148

  6. Conjugation with polyamines enhances the antibacterial and anticancer activity of chloramphenicol

    Science.gov (United States)

    Kostopoulou, Ourania N.; Kouvela, Ekaterini C.; Magoulas, George E.; Garnelis, Thomas; Panagoulias, Ioannis; Rodi, Maria; Papadopoulos, Georgios; Mouzaki, Athanasia; Dinos, George P.; Papaioannou, Dionissios; Kalpaxis, Dimitrios L.

    2014-01-01

    Chloramphenicol (CAM) is a broad-spectrum antibiotic, limited to occasional only use in developed countries because of its potential toxicity. To explore the influence of polyamines on the uptake and activity of CAM into cells, a series of polyamine–CAM conjugates were synthesized. Both polyamine architecture and the position of CAM-scaffold substitution were crucial in augmenting the antibacterial and anticancer potency of the synthesized conjugates. Compounds 4 and 5, prepared by replacement of dichloro-acetyl group of CAM with succinic acid attached to N4 and N1 positions of N8,N8-dibenzylspermidine, respectively, exhibited higher activity than CAM in inhibiting the puromycin reaction in a bacterial cell-free system. Kinetic and footprinting analysis revealed that whereas the CAM-scaffold preserved its role in competing with the binding of aminoacyl-tRNA 3′-terminus to ribosomal A-site, the polyamine-tail could interfere with the rotatory motion of aminoacyl-tRNA 3′-terminus toward the P-site. Compared to CAM, compounds 4 and 5 exhibited comparable or improved antibacterial activity, particularly against CAM-resistant strains. Compound 4 also possessed enhanced toxicity against human cancer cells, and lower toxicity against healthy human cells. Thus, the designed conjugates proved to be suitable tools in investigating the ribosomal catalytic center plasticity and some of them exhibited greater efficacy than CAM itself. PMID:24939899

  7. Electrochemical pre anodization of glassy carbon electrode and application to determine chloramphenicol

    International Nuclear Information System (INIS)

    This paper suggested a method to enhance the performance of carbon electrodes for the determination of chloramphenicol (CAP). The sensitivity and the reproducibility of the carbon electrodes could be enhanced easily by electrochemical pretreatment. Some kinds of carbon material were studied including glassy carbon, graphite carbon and pyrolytic carbon. Numerous kinds of supporting electrolyte have been tried. For glassy carbon electrode, the acidic solution, H2SO4 5 mM, resulted in best performance at pretreated voltage of +2.1V (vs. Ag/ AgCl) in duration of 250 second. However, for graphite and pyrolytic carbon electrodes, the phosphate buffer solution pH 6.0 gave the best performance at +1.7V (vs. Ag/ AgCl) in duration of 20 seconds. The detection limit could be at very low concentration of CAP: 0.8 ng/ ml for glassy carbon electrode, 3.5 ng/ ml for graphite carbon electrode. The method was successful applied to aqua-agriculture water sample and milk sample with simple extraction as well as direct ointment sample analysis. (author)

  8. [Bioanode and Inversion of Bioanode to Biocathode for the Degradation of Antibiotic Chloramphenicol].

    Science.gov (United States)

    Kong, De-yong; Liang, Bin; Yun, Hui; Wang, Ai-jie; Ren, Nan-qi

    2015-04-01

    In order to investigate the possibility of the normal bioanode and bioanode switched to biocathode for the bio-electrochemical degradation of the antibiotic chloramphenicol (CAP), both the bioanode acclimated with CAP and the biocathode inversed from bioanode were monitored for CAP degradation in the bio-electrochemical system. The results demonstrated that the normal enriched bioanode could simultaneously generate current and degrade CAP (k = 0.098 5, 35 mg x L(-1) of CAP) after a long-term acclimation by gradually increasing the concentration of CAP from 5 mg x L(-1) to 80 mg x L(-1). After switching bioanode to biocathode, the cathode biofilm was still capable of catalyzing CAP degradation, although it was influenced to some extent due to changed electrode potential from -0.20 V to -0.40 V vs. standard hydrogen electrode (SHE). The k of biocathode was 0.264 3, significantly higher than that of abiotic cathode (k = 0.160 9). This mode of biocathode, which was switched from bioanode, not only had the ability of reducing nitro group in CAP but also catalyzed the complete dechloridation and carbanyl group reduction of the side chain of aromatic amine product. PMID:26164911

  9. Distribution and chloramphenicol in the bovine genital tract and pharmacokinetic studies of florfenicol in cattle

    International Nuclear Information System (INIS)

    The objectives were to investigate selected aspects of the distribution of chloramphenicol (CAP) in the bovine genital tract and to conduct preliminary pharmacologic studies with florfenicol (FLO), a fluorinated analogue of thiamphenicol, in cattle. After 8 hours' continuous intravenous (IV) infusion of CAP to 7 postpartum cows, steady state plasma-to-genital tissue ratios of CAP were approximately 3. After intrauterine infusion of 20 mg CAP/kg to 3 postpartum cows, approximately 40% of the dose was absorbed into the bloodstream. Tissue concentrations were high at 8 hour postdosing in tissues lining the uterine lumen but were below desired therapeutic concentrations in the myometrium of 2 of the cows. Eighty cows with retained fetal membranes (RFM) were assigned to receive on the following treatments: (1) removal of membranes only; (2) removal plus CAP; (3) nonremoval; (4) nonremoval plus CAP. CAP treatment consisted of 5 g administered IU twice daily for 3 days. The majority of cows in all groups acquired endometritis, although CAP reduced the prevalence and severity of the disease. A quantitative assay for FLO in plasma was developed and validated on a high performance liquid chromatographic (HPLC) system. The pharmacokinetics of FLO determined after IV administration of 50 mg FLO/kg to 5 cows were best described by a three-compartment model. FLO was approximately 18% bound to plasma proteins as determined by equilibrium dialysis and ultrafiltration. In an in vitro system, 5, 125, or 1000 ug/ml of CAP had no effect on neutrophils from 6 cows

  10. Rapid Detection of Chloramphenicol Residues in Aquatic Products Using Colloidal Gold Immunochromatographic Assay

    Directory of Open Access Journals (Sweden)

    Chennan Zhou

    2014-11-01

    Full Text Available A colloidal gold immunochromatographic assay (GICA was developed for rapid detection of chloramphenicol (CAP residues in aquatic products. A nitrocellulose (NC membrane was used as the carrier, and the polyclonal CAP antibody was used as the marker protein. The average diameter of as-prepared colloidal gold nanoparticles (AuNPs was about 20 nm. The optimal pH value of colloidal gold solutions and the amount of the antibody of CAP were 8.0 and 7.2 μg/mL, respectively. The CAP antibody was immobilized onto the conjugate pad after purification. The CAP conjugate and goat anti-rabbit IgG (secondary antibody were coated onto the NC membrane. Next, the non-specific sites were blocked with 1% bovine serum albumin. The minimum detectable concentration of CAP in standard solution is 0.5 ng/mL, with good reproducibility. For the real samples from crucian carps injected with a single-dose of CAP in the dorsal muscles, the minimum detectable concentration of CAP residues was 0.5 µg/kg. The chromatographic analysis time was less than 10 min, and the strip had a long storage lifetime of more than 90 days at different temperatures. The strips provide a means for rapid detection of CAP residues in aquatic products.

  11. Establishment of magnetic beads-based enzyme immunoassay for detection of chloramphenicol in milk.

    Science.gov (United States)

    Xu, Jing; Yin, Weiwei; Zhang, Yuanyang; Yi, Jian; Meng, Meng; Wang, Yabin; Xue, Huyin; Zhang, Taichang; Xi, Rimo

    2012-10-15

    In this research, magnetic beads-based enzyme immunoassays were investigated for rapid analysis of chloramphenicol (CAP) in milk. To improve sensitivity of CAP determination, two kinds of immunomagnetic separation methods were designed and compared. Magnetic polystyrene microspheres were conjugated with anti-CAP antibody (Method I) or goat-anti-mouse IgG (Method II). The whole determination could be finished in 1.25 h. Both methods showed high sensitivity to CAP in buffer, and obtained an IC(50) value of 0.05 ng mL(-1) for Method I and 0.4 ng mL(-1) for Method II. The methods showed high specificity, only showing a little cross-reaction towards CAP succinate. The two methods were applied to detect CAP in milk. The recovery rates were 80-106% and the coefficients of variation (CVs) were 4.7-15%. The immunomagnetic assay showed promising potential in rapid screening field for CAP analysis. Between the two methods, Method I is more sensitive, and Method II is more suitable for producing a general assay by changing a primary antibody for another analyte. PMID:23442720

  12. Source identification and entry pathways of banned antibiotics nitrofuran and chloramphenicol in shrimp value chain of Bangladesh

    OpenAIRE

    M. Jakiul Islam; Afroza Akter Liza; A.H.M. Mohsinul Reza; M. Shaheed Reza; Mohammed Nurul Absar Khan; Md. Kamal

    2014-01-01

    Background: Contamination with residues of banned carcinogenic antibiotic drugs like nitrofuran metabolites and chloramphenicol (CAP) in frozen shrimp products has become a major concern of food safety for exporting countries. In the present study an approach was taken to identify the sources of such harmful antibiotics in the shrimp value chain of Bangladesh, one of the major shrimp countries. Materials and Methods: Inputs of farms and hatchery systems including feed, feed additives, fee...

  13. Evaluation of Amphotericin B and Chloramphenicol as Alternative Drugs for Treatment of Chytridiomycosis and Their Impacts on Innate Skin Defenses

    OpenAIRE

    Holden, Whitney M.; Ebert, Alexander R.; Canning, Peter F.; Rollins-Smith, Louise A.

    2014-01-01

    Chytridiomycosis, an amphibian skin disease caused by the emerging fungal pathogen Batrachochytrium dendrobatidis, has been implicated in catastrophic global amphibian declines. The result is an alarming decrease in amphibian diversity that is a great concern for the scientific community. Clinical trials testing potential antifungal drugs are needed to identify alternative treatments for amphibians infected with this pathogen. In this study, we quantified the MICs of chloramphenicol (800 μg/m...

  14. Comparative Study on the Synergistic Action of Differentially Synthesized Silver Nanoparticles with β-Cephem Antibiotics and Chloramphenicol

    Directory of Open Access Journals (Sweden)

    Neethu Hari

    2014-01-01

    Full Text Available Synergistic activity of cephem antibiotics with silver nanoparticles (Ag NPs was investigated. Silver nanoparticles were synthesized through biological and chemical method. The combined action of β-lactam cephem antibiotics with both green and chemically synthesized silver nanoparticles enhances the antibacterial activity against wide range of antibiotic resistant pathogens and making them applicable to medical devices and microbial control systems. Synergistic activity of chloramphenicol with silver nanoparticles was also studied.

  15. Comparative Study on the Synergistic Action of Differentially Synthesized Silver Nanoparticles with β-Cephem Antibiotics and Chloramphenicol

    International Nuclear Information System (INIS)

    Synergistic activity of cephem antibiotics with silver nanoparticles (Ag NPs) was investigated. Silver nanoparticles were synthesized through biological and chemical method. The combined action of β-lactam cephem antibiotics with both green and chemically synthesized silver nanoparticles enhances the antibacterial activity against wide range of antibiotic resistant pathogens and making them applicable to medical devices and microbial control systems. Synergistic activity of chloramphenicol with silver nanoparticles was also studied.

  16. Synthesis and Evaluation of Molecularly Imprinted Polymeric Microspheres for Chloramphenicol by Aqueous Suspension Polymerization as a High Performance Liquid Chromatography Stationary Phase

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan [Beijing Forestry Univ., Beijing (China); Lei, Jiandu [Univ., of Science and Technology, Beijing (Korea, Republic of)

    2013-06-15

    Molecularly imprinted microsphere for chloramphenicol (CAP) with high adsorption capacity and excellent selectivity is prepared by aqueous suspension polymerization, in which chloramphenicol is used as template molecule and ethyl acetate as porogen. The CAP-imprinted microspheres are used as high performance liquid chromatography (HPLC) stationary phase and packed into stainless steel column (150 mm Χ 4.6 mm i. d.) for selective separation of chloramphenicol. HPLC analysis suggests that chloramphenicol can be distinguished from not only its structural analogs but also other broad-spectrum antibiotic such as erythromycin and tetracycline. In addition, the binding experiments of CAP-imprinted microspheres are carried out in ethanol/water (1:4, V:V), the results indicate that the maximum apparent static binding capacity of molecularly imprinted microspheres is up to 66.64 mg g{sup -1} according to scatchard model.

  17. Synthesis and Evaluation of Molecularly Imprinted Polymeric Microspheres for Chloramphenicol by Aqueous Suspension Polymerization as a High Performance Liquid Chromatography Stationary Phase

    International Nuclear Information System (INIS)

    Molecularly imprinted microsphere for chloramphenicol (CAP) with high adsorption capacity and excellent selectivity is prepared by aqueous suspension polymerization, in which chloramphenicol is used as template molecule and ethyl acetate as porogen. The CAP-imprinted microspheres are used as high performance liquid chromatography (HPLC) stationary phase and packed into stainless steel column (150 mm Χ 4.6 mm i. d.) for selective separation of chloramphenicol. HPLC analysis suggests that chloramphenicol can be distinguished from not only its structural analogs but also other broad-spectrum antibiotic such as erythromycin and tetracycline. In addition, the binding experiments of CAP-imprinted microspheres are carried out in ethanol/water (1:4, V:V), the results indicate that the maximum apparent static binding capacity of molecularly imprinted microspheres is up to 66.64 mg g-1 according to scatchard model

  18. Adsorption behavior and mechanism of chloramphenicols, sulfonamides, and non-antibiotic pharmaceuticals on multi-walled carbon nanotubes.

    Science.gov (United States)

    Zhao, Heng; Liu, Xue; Cao, Zhen; Zhan, Yi; Shi, Xiaodong; Yang, Yi; Zhou, Junliang; Xu, Jiang

    2016-06-01

    The adsorption behavior of different emerging contaminants (3 chloramphenicols, 7 sulfonamides, and 3 non-antibiotic pharmaceuticals) on five types of multi-walled carbon nanotubes (MWCNTs), and the underlying factors were studied. Adsorption equilibriums were reached within 12h for all compounds, and well fitted by the Freundlich isotherm model. The adsorption affinity of pharmaceuticals was positively related to the specific surface area of MWCNTs. The solution pH was an important parameter of pharmaceutical adsorption on MWCNTs, due to its impacts on the chemical speciation of pharmaceuticals and the surface electrical property of MWCNTs. The adsorption of ionizable pharmaceuticals decreased in varying degrees with the increased ionic strength. MWCNT-10 was found to be the strongest adsorbent in this study, and the Freundlich constant (KF) values were 353-2814mmol(1-n)L(n)/kg, 571-618mmol(1-n)L(n)/kg, and 317-1522mmol(1-n)L(n)/kg for sulfonamides, chloramphenicols, and non-antibiotic pharmaceuticals, respectively. The different adsorption affinity of sulfonamides might contribute to the different hydrophobic of heterocyclic substituents, while chloramphenicols adsorption was affected by the charge distribution in aromatic rings via substituent effects. PMID:26937870

  19. Does single application of topical chloramphenicol to high risk sutured wounds reduce incidence of wound infection after minor surgery? Prospective randomised placebo controlled double blind trial

    OpenAIRE

    Heal, Clare F; Petra G Buettner; Cruickshank, Robert; Graham, David; Browning, Sheldon; Pendergast, Jayne; Drobetz, Herwig; Gluer, Robert; Lisec, Carl

    2009-01-01

    Objective To determine the effectiveness of a single application of topical chloramphenicol ointment in preventing wound infection after minor dermatological surgery. Design Prospective randomised placebo controlled double blind multicentre trial. Setting Primary care in a regional centre in Queensland, Australia. Participants 972 minor surgery patients. Interventions A single topical dose of chloramphenicol (n=488) or paraffin ointment (n=484; placebo). Main outcome measure Incidence of infe...

  20. Degradação eletroquímica do cloranfenicol em reator de fluxo Electrochemical degradation of the chloramphenicol at flow reactor

    OpenAIRE

    Luis Gustavo P. Rezende; Vânia M. do Prado; Robson S. Rocha; André A. G. F. Beati; Maria Del Pilar T. Sotomayor; Marcos R. V. Lanza

    2010-01-01

    This paper reports a study of electrochemical degradation of the chloramphenicol antibiotic in aqueous medium using a flow-by reactor with DSA® anode. The process efficiency was monitored by chloramphenicol concentration analysis with liquid chromatography (HPLC) during the experiments. Analysis of Total Organic Carbon (TOC) was performed to estimate the degradation degree and Ion Chromatography (IC) was performed to determinate inorganic ions formed during the eletrochemical degradation proc...

  1. Detection of chloramphenicol residue in bovine meat using Liquid Chromatography Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Widiastuti R

    2014-03-01

    Full Text Available Chloramphenicol (CAP is a broad spectrum antibiotic that has been banned in many countries due to its serius side effect to human. Detection of CAP residue in food has been determined to a minimum required performance limit (MRPL of 0.3 ng/g. The purpose of this research was to conduct the analysis of CAP residue in bovine meat by using LCMS and to study the presence of CAP residue in marketed bovine meat samples. LC separation was done on a Shimpack column C18 with ammonium acetate 10 mM/water as mobile phase, and ESI-MS analysis in negative ion mode. The coefficient of determination, R2 = 0.9981 at concentration of 0.125, 0.25, 0.63, 1,00 and 2.00 ng/g. Recovery at three fortification levels (0.25, 0.50 and 1.00 ng/g was in the range 77.5, 97.3 and 83.4%. The decision limit and the detection capability were 0.15 ng/g and 0.17 ng/g respectively. Analysis results of 52 marketed samples showed that CAP residue were detected in 9 samples in the concentration range of 0.14 to 2.70 ng/g and 6 among those positive samples were above the MRPL value. Therefore, it is important to increase the awareness and also to monitor regularly CAP residues in food originated from animal to provide safe food for the consumers.

  2. Biotin-avidin-conjugated metal sulfide nanoclusters for simultaneous electrochemical immunoassay of tetracycline and chloramphenicol

    International Nuclear Information System (INIS)

    We report on a protocol for a simultaneous competitive immunoassay for tetracycline (TC) and chloramphenicol (CAP) on the same sensing interface. Conjugates of TC and of CAP with bovine serum albumin were first co-immobilized on a glassy carbon electrode modified with gold nanoparticles. In parallel, monoclonal anti-TC and anti-CAP antibodies were conjugated onto CdS and PbS nanoclusters, respectively. In a typical assay, the immobilized haptens and the added target analytes competed for binding to the corresponding antibodies on the nanoclusters. Subsequently, Cd(II) and Pb(II) ions are released from the surface of the corresponding nanoclusters by treatment with acid and then were detected by square wave anodic stripping voltammetry. The currents at the peak potentials for Cd(II) and Pb(II) were used as the sensor signal for TC and CAP, respectively. This multiplex immunoassay enables the simultaneous determination of TC and CAP in a single run with dynamic ranges from 0.01 to 50 ng mL−1 for both analytes. The detection limits for TC and for CAP are 7.5 pg mL−1 and 5.4 pg mL−1, respectively. No obvious nonspecific adsorption and cross-reactivity was observed in a series of analyses. Intra-assay and inter-assay coefficients of variation were less than 10 %. The method was evaluated by analyzing TC and CAP in spiked samples of milk and honey. The recoveries range from 88 % to 107 % for TC, and from 91 % to 119 % for CAP. (author)

  3. HPLC-MS Analysis of Chloramphenicol Residues in Milk and Powdered Milk Products

    Directory of Open Access Journals (Sweden)

    Bošnir, J.

    2007-02-01

    Full Text Available Chloramphenicol (CAP is a broad-spectrum antibiotic with bacteriostatic action but also has toxic properties, which is why its presence in food and feed is prohibited in Croatia and the European Union.In the aim of consumer protection it is essential to develop a sensitive analytical method for detection of CAP fractions lower than w = 0.3 µg kg-1. For the efficient control and monitoring of CAP, a rapid, sensitive, and selective method for its identification and quantification, using highperformance liquid chromatography in combination with mass spectrometry LC-MS, has been developed.The cleaning procedure was based on the AOAC official method 993.32. HPLC-MS analysis used the ODS Hypersile column and the water/acetonitrile gradient. Electrospray negative ionization (neg ESI was used before single ion monitoring (SIM detection of three m/z 321, 323 and 325. As additional criteria, the ratio between these masses in real and spiked milk samples was also investigated in accordance with theoretical values of the isotope pattern for 2 chlorine atoms present in the analyte.The detection limit of 0.1 µg kg-1 was achieved. The mean value of recovery was 94 %, the correlation coefficient of the calibration curves calculated for 2 m/z values was higher than 0.99.Fourty samples of milk and milk products were tested with the HPLC-MS method, and obtained results showed that samples had CAP 0.37, 0.29, 0.39 µg kg-1, respectively. All the other analysed samples contained CAP concentrations below the detection limit.

  4. Radiation sensitivity of Salmonella isolates relative to resistance to ampicillin, chloramphenicol or gentamicin

    International Nuclear Information System (INIS)

    Antibiotic resistance of inoculated bacteria is a commonly used selective marker. Bacteria resistant to the antibiotic nalidixic acid have been shown to have an increased sensitivity to irradiation. The purpose of this research was to screen a collection of Salmonella isolates for antibiotic resistance and determine the association, if any, of antibiotic resistance with radiation sensitivity. Twenty-four clinical isolates of Salmonella were screened for native resistance to multiple concentrations of ampicillin (Amp), chloramphenicol (Chl), or gentamicin (Gm). Test concentrations were chosen based on established clinical minimum inhibitory concentration (MIC) levels, and isolates were classified as either sensitive or resistant based on their ability to grow at or above the MIC. Salmonella cultures were grown overnight at (37 oC) in antibiotic-amended tryptic soy broth (TSB). Native resistance to Gm was observed with each of the 24 isolates (100%). Eight isolates (33%) were shown to be resistant to Amp, while seven isolates (29%) were shown to be resistant to Chl. In separate experiments, Salmonella cultures were grown overnight (37 oC) in TSB, centrifuged, and the cell pellets were re-suspended in phosphate buffer. The samples were then gamma irradiated at doses up to 1.0 kGy. The D 10 values (the ionizing radiation dose required to reduce the viable number of microorganisms by 90%) were determined for the 24 isolates and they ranged from 0.181 to 0.359 kGy. No correlation was found between the D 10 value of the isolate and its sensitivity or resistance to each of the three antibiotics. Resistance to Amp or Chl is suggested as appropriate resistance marker for Salmonella test strains to be used in studies of irradiation

  5. Distribution and chloramphenicol in the bovine genital tract and pharmacokinetic studies of florfenicol in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Bretzlaff, K.N.

    1986-01-01

    The objectives were to investigate selected aspects of the distribution of chloramphenicol (CAP) in the bovine genital tract and to conduct preliminary pharmacologic studies with florfenicol (FLO), a fluorinated analogue of thiamphenicol, in cattle. After 8 hours' continuous intravenous (IV) infusion of CAP to 7 postpartum cows, steady state plasma-to-genital tissue ratios of CAP were approximately 3. After intrauterine infusion of 20 mg CAP/kg to 3 postpartum cows, approximately 40% of the dose was absorbed into the bloodstream. Tissue concentrations were high at 8 hour postdosing in tissues lining the uterine lumen but were below desired therapeutic concentrations in the myometrium of 2 of the cows. Eighty cows with retained fetal membranes (RFM) were assigned to receive on the following treatments: (1) removal of membranes only; (2) removal plus CAP; (3) nonremoval; (4) nonremoval plus CAP. CAP treatment consisted of 5 g administered IU twice daily for 3 days. The majority of cows in all groups acquired endometritis, although CAP reduced the prevalence and severity of the disease. A quantitative assay for FLO in plasma was developed and validated on a high performance liquid chromatographic (HPLC) system. The pharmacokinetics of FLO determined after IV administration of 50 mg FLO/kg to 5 cows were best described by a three-compartment model. FLO was approximately 18% bound to plasma proteins as determined by equilibrium dialysis and ultrafiltration. In an in vitro system, 5, 125, or 1000 ug/ml of CAP had no effect on neutrophils from 6 cows.

  6. Assessment of commutability for candidate certified reference material ERM-BB130 "chloramphenicol in pork".

    Science.gov (United States)

    Zeleny, Reinhard; Emteborg, Håkan; Schimmel, Heinz

    2010-10-01

    Chloramphenicol (CAP), an effective antibiotic against many microorganisms, is meanwhile banned in the EU for treatment of food-producing animals due to adverse health effects. The Institute for Reference Materials and Measurements (IRMM) is currently developing a certified reference material (CRM) for CAP in pork, intended for validation and method performance verifications of analytical methods. The material will be certified using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) methods and has a target CAP level around the minimum required performance limit (MRPL) of 0.3 microg/kg. To prove that the material can be applied as a quality control tool for screening methods, a commutability study was conducted, involving five commercially available enzyme-linked immunosorbent assay kits and one biosensor assay (BiaCore kit). Meat homogenates (cryo-milled wet tissue) with CAP concentrations around the MRPL and the candidate CRM (lyophilised powder) were measured by LC-MS/MS and GC-MS as well as the six screening methods. Pairwise method comparisons of results obtained for the two sample types showed that the CRM can successfully be applied as quality control (QC) sample to all six screening methods. The study suggests that ERM-BB130 is sufficiently commutable with the investigated assays and that laboratories applying one of the investigated kits therefore benefit from using ERM-BB130 to demonstrate the correctness of their results. However, differences among the assays were observed, either in the abundance of bias between screening and confirmatory LC and GC methods, the repeatability of test results, or goodness of fit between the methods. PMID:20665007

  7. Chloramphenicol Biosynthesis: The Structure of CmlS, a Flavin-Dependent Halogenase Shwing a Covalent Flavin-Aspartate Bond

    International Nuclear Information System (INIS)

    Chloramphenicol is a halogenated natural product bearing an unusual dichloroacetyl moiety that is critical for its antibiotic activity. The operon for chloramphenicol biosynthesis in Streptomyces venezuelae encodes the chloramphenicol halogenase CmlS, which belongs to the large and diverse family of flavin-dependent halogenases (FDH's). CmlS was previously shown to be essential for the formation of the dichloroacetyl group. Here we report the X-ray crystal structure of CmlS determined at 2.2 (angstrom) resolution, revealing a flavin monooxygenase domain shared by all FDHs, but also a unique 'winged-helix' C-terminal domain that creates a T-shaped tunnel leading to the halogenation active site. Intriguingly, the C-terminal tail of this domain blocks access to the halogenation active site, suggesting a structurally dynamic role during catalysis. The halogenation active site is notably nonpolar and shares nearly identical residues with Chondromyces crocatus tyrosyl halogenase (CndH), including the conserved Lys (K71) that forms the reactive chloramine intermediate. The exception is Y350, which could be used to stabilize enolate formation during substrate halogenation. The strictly conserved residue E44, located near the isoalloxazine ring of the bound flavin adenine dinucleotide (FAD) cofactor, is optimally positioned to function as a remote general acid, through a water-mediated proton relay, which could accelerate the reaction of the chloramine intermediate during substrate halogenation, or the oxidation of chloride by the FAD(C4α)-OOH intermediate. Strikingly, the 8α carbon of the FAD cofactor is observed to be covalently attached to D277 of CmlS, a residue that is highly conserved in the FDH family. In addition to representing a new type of flavin modification, this has intriguing implications for the mechanism of FDHs. Based on the crystal structure and in analogy to known halogenases, we propose a reaction mechanism for CmlS.

  8. Sensitive voltammetric determination of chloramphenicol by using single-wall carbon nanotube-gold nanoparticle-ionic liquid composite film modified glassy carbon electrodes

    International Nuclear Information System (INIS)

    A novel composite film modified glassy carbon electrode has been fabricated and characterized by scanning electron microscope (SEM) and voltammetry. The composite film comprises of single-wall carbon nanotube (SWNT), gold nanoparticle (GNP) and ionic liquid (i.e. 1-octyl-3-methylimidazolium hexafluorophosphate), thus has the characteristics of them. The resulting electrode shows good stability, high accumulation efficiency and strong promotion to electron transfer. On it, chloramphenicol can produce a sensitive cathodic peak at -0.66 V (versus SCE) in pH 7.0 phosphate buffer solutions. Parameters influencing the voltammetric response of chloramphenicol are optimized, which include the composition of the film and the operation conditions. Under the optimized conditions, the peak current is linear to chloramphenicol concentration in the range of 1.0 x 10-8-6.0 x 10-6 M, and the detection limit is estimated to be 5.0 x 10-9 M after an accumulation for 150 s on open circuit. The electrode is applied to the determination of chloramphenicol in milk samples, and the recoveries for the standards added are 97.0% and 100.3%. In addition, the electrochemical reaction of chloramphenicol and the effect of single-wall carbon nanotube, gold nanoparticle and ionic liquid are discussed

  9. Stress degradation studies and development of stability-indicating TLC-densitometry method for determination of prednisolone acetate and chloramphenicol in their individual and combined pharmaceutical formulations

    Directory of Open Access Journals (Sweden)

    Musharraf Syed

    2012-01-01

    Full Text Available Abstract A rapid and reproducible stability indicating TLC method was developed for the determination of prednisolone acetate and chloramphenicol in presence of their degraded products. Uniform degradation conditions were maintained by refluxing sixteen reaction mixtures for two hours at 80°C using parallel synthesizer including acidic, alkaline and neutral hydrolysis, oxidation and wet heating degradation. Oxidation at room temperature, photochemical and dry heating degradation studies were also carried out. Separation was done on TLC glass plates, pre-coated with silica gel 60F-254 using chloroform: methanol (14:1 v/v. Spots at Rf 0.21 ± 0.02 and Rf 0.41 ± 0.03 were recognized as chloramphenicol and prednisolone acetate, respectively. Quantitative analysis was done through densitometric measurements at multiwavelength (243 nm, λmax of prednisolone acetate and 278 nm, λmax of chloramphenicol, simultaneously. The developed method was optimized and validated as per ICH guidelines. Method was found linear over the concentration range of 200-6000 ng/spot with the correlation coefficient (r2 ± S.D. of 0.9976 ± 3.5 and 0.9920 ± 2.5 for prednisolone acetate and chloramphenicol, respectively. The developed TLC method can be applied for routine analysis of prednisolone acetate and chloramphenicol in presence of their degraded products in their individual and combined pharmaceutical formulations.

  10. Synthesis of nitrogen-doped graphene nanosheets decorated with gold nanoparticles as an improved sensor for electrochemical determination of chloramphenicol

    International Nuclear Information System (INIS)

    Highlights: • Nitrogen doped graphene decorated with gold nanoparticles were synthesized. • Au nanoparticles improved the surface area and electron transfer properties of N-G. • Au/N-G composite markedly enhanced the voltammetric response of chloramphenicol. • CAP in real sample was successfully determined on Au/N-G modified electrode. -- Abstract: Nitrogen-doped graphene nanosheets decorated with gold nanoparticles (Au/N-G) were synthesized by the reduction of HAuCl4 on the surface of N-G using ethylene glycol as the reducing agent. The surface characterization with various techniques such as scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy showed that many gold nanoparticles were effectively loaded on the surface of N-G via the proposed synthesis process. The impedance analysis indicated that Au/N-G was an excellent electrode material possessing outstanding electrochemical features for electron transfer. Using Au/N-G modified electrode, the electrochemical response of chloramphenicol (CAP) was significantly increased due to the synergetic effect of two nanomaterials. Thus, a high-performance electrochemical sensor for CAP based on Au/N-G was developed

  11. Green synthesized gold nanoparticles decorated graphene oxide for sensitive determination of chloramphenicol in milk, powdered milk, honey and eye drops.

    Science.gov (United States)

    Karthik, R; Govindasamy, Mani; Chen, Shen-Ming; Mani, Veerappan; Lou, Bih-Show; Devasenathipathy, Rajkumar; Hou, Yu-Shen; Elangovan, A

    2016-08-01

    A simple and rapid green synthesis using Bischofia javanica Blume leaves as reducing agent was developed for the preparation of gold nanoparticles (AuNPs). AuNPs decorated graphene oxide (AuNPs/GO) was prepared and employed for the sensitive amperometric determination of chloramphenicol. The green biosynthesis requires less than 40s to reduce gold salts to AuNPs. The formations of AuNPs and AuNPs/GO were evaluated by scanning electron and atomic force microscopies, UV-Visible and energy dispersive X-ray spectroscopies, X-ray diffraction studies, and electrochemical methods. AuNPs/GO composite film modified electrode was fabricated and shown excellent electrocatalytic ability towards chloramphenicol. Under optimal conditions, the amperometric sensing platform has delivered wide linear range of 1.5-2.95μM, low detection limit of 0.25μM and high sensitivity of 3.81μAμM(-1)cm(-2). The developed sensor exhibited good repeatability and reproducibility, anti-interference ability and long-term storage stability. Practical feasibility of the sensor has been demonstrated in food samples (milk, powdered milk and honey) and pharmaceutical sample (eye drops). The green synthesized AuNPs/GO composite has great potential for analysis of food samples in food safety measures. PMID:27153217

  12. Degradação eletroquímica do cloranfenicol em reator de fluxo Electrochemical degradation of the chloramphenicol at flow reactor

    Directory of Open Access Journals (Sweden)

    Luis Gustavo P. Rezende

    2010-01-01

    Full Text Available This paper reports a study of electrochemical degradation of the chloramphenicol antibiotic in aqueous medium using a flow-by reactor with DSA® anode. The process efficiency was monitored by chloramphenicol concentration analysis with liquid chromatography (HPLC during the experiments. Analysis of Total Organic Carbon (TOC was performed to estimate the degradation degree and Ion Chromatography (IC was performed to determinate inorganic ions formed during the eletrochemical degradation process. In electrochemical flow-by reactor, 52% of chloramphenicol was degraded, with 12% TOC reduction. IC analysis showed the production of chloride ions (25 mg L-1, nitrate ions (6 mg L-1 and nitrite ions (4.5 mg L-1.

  13. Chloramphenicol encapsulated in poly-ε-caprolactone–pluronic composite: nanoparticles for treatment of MRSA-infected burn wounds

    Directory of Open Access Journals (Sweden)

    Kalita S

    2015-04-01

    Full Text Available Sanjeeb Kalita,1 Banasmita Devi,1 Raghuram Kandimalla,1 Kaustav Kalyan Sharma,1 Arup Sharma,2 Kasturi Kalita,3 Amal Chandra Kataki,4 Jibon Kotoky1 1Institute of Advanced Study in Science and Technology (IASST, Division of Life Sciences, Paschim Boragaon, Garchuk, Guwahati, Assam, India; 2College of Veterinary Science, Assam Agriculture University, Khanapara, Guwahati, Assam, India; 3Hyat Hospital, Lalganesh, Guwahati, Assam, India; 4Dr B Borooah Cancer Institute, Guwahati, Assam, India Abstract: The emergence of methicillin-resistant Staphylococcus aureus (MRSA infection has increased precipitously over the past several decades, with far-reaching health care and societal costs. MRSA infections in the context of burn wounds lead to invasive disease that could potentially cause mortality. Chloramphenicol is a well-known broad-spectrum bacteriostatic antibiotic that has been used since 1949, but due to its hydrophobicity, poor penetration in skin, fast degradation, and toxicity, its application has been hindered. Furthermore, it has been demonstrated that old antibiotics such as chloramphenicol remained active against a large number of currently prevalent resistant bacterial isolates due to their low-level use in the past. Recently, the novel nanoparticulate drug-delivery system has been used and reported to be exceptionally useful for topical therapeutics, due to its distinctive physical characteristics such as a high surface-to-volume ratio and minuscule size. It helps to achieve better hydrophilicity, bioavailability, and controlled delivery with enhanced therapeutic index, which has resulted in decreased toxicity levels compared to the crude drug. Here, we report a novel chloramphenicol loaded with poly(ε-caprolactone (PCL-pluronic composite nanoparticles (CAM-PCL-P NPs, physicochemical characterizations, and its bioactivity evaluation in a MRSA-infected burn-wound animal model. CAM-PCL-P NPs could encapsulate 98.3% of the drug in the

  14. The importance of highly conserved nucleotides in the binding region of chloramphenicol at the peptidyl transfer centre of Escherichia coli 23S ribosomal RNA

    DEFF Research Database (Denmark)

    Vester, Birte; Garrett, Roger Antony

    1988-01-01

    The peptidyl transfer site has been localized at the centre of domain V of 23S-like ribosomal RNA (rRNA) primarily on the basis of a chloramphenicol binding site. The implicated region constitutes an unstructured circle in the current secondary structural model which contains several universally....... In addition, a G2502----A transition caused a decreased growth rate, probably due to a partial selection against mutant ribosome incorporation into polysomes, while an A2503----C transversion produced a decreased growth rate and conferred resistance to chloramphenicol. All of the mutant RNAs were...

  15. Food safety evaluation: Detection and confirmation of chloramphenicol in milk by high performance liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    A simple and rapid procedure for extraction of chloramphenicol (CAP) in milk and analysis by high-performance liquid chromatography coupled with quadrupole mass spectrometry in tandem was developed. The method consisted of one step of liquid-liquid extraction using ethyl acetate and acidified water (10 mmol L-1 formic acid) and HPLC-MS/MS detection. CAP-D5 was used as internal standard. The method was validated according to Commission Decision 2002/657/EC. The calibration curves were linear, with typical r 2 values higher than 0.98. Absolute recovery of CAP from milk proved to be more than 95%, however CAP-D5 absolute recovery was 75%. The method was accurate and reproducible, being successfully applied to the monitoring of CAP in milk samples obtained from the Brazilian market. Decision limit (CCα) was 0.05 ng mL-1 and detection capability (CCβ) was 0.09 ng mL-1

  16. Enhanced inhibition of bacterial biofilm formation and reduced leukocyte toxicity by chloramphenicol:β-cyclodextrin:N-acetylcysteine complex.

    Science.gov (United States)

    Aiassa, Virginia; Zoppi, Ariana; Becerra, M Cecilia; Albesa, Inés; Longhi, Marcela R

    2016-11-01

    The purpose of this study was to improve the physicochemical and biological properties of chloramphenicol (CP) by multicomponent complexation with β-cyclodextrin (β-CD) and N-acetylcysteine (NAC). The present work describes the ability of solid multicomponent complex (MC) to decrease biomass and cellular activity of Staphylococcus by crystal violet and XTT assay, and leukocyte toxicity, measuring the increase of reactive oxygen species by chemiluminescence, and using 123-dihydrorhodamine. In addition, MC was prepared by the freeze-drying or physical mixture methods, and then characterized by scanning electron microscopy and powder X-ray diffraction. Nuclear magnetic resonance and phase solubility studies provided information at the molecular level on the structure of the MC and its association binding constants, respectively. The results obtained allowed us to conclude that MC formation is an effective pharmaceutical strategy that can reduce CP toxicity against leukocytes, while enhancing its solubility and antibiofilm activity. PMID:27516318

  17. Abrp, a new gene, confers reduced susceptibility to tetracycline, glycylcine, chloramphenicol and fosfomycin classes in Acinetobacter baumannii.

    Science.gov (United States)

    Li, X; Quan, J; Yang, Y; Ji, J; Liu, L; Fu, Y; Hua, X; Chen, Y; Pi, B; Jiang, Y; Yu, Y

    2016-08-01

    Acinetobacter baumannii, a non-fermenting gram-negative coccobacillus, is a major pathogen responsible for a variety of healthcare-associated infections, including pneumonia, urinary tract and bloodstream infections. Moreover, A. baumannii is associated with alarming increases in drug resistance rates to almost all available antibiotics leaving limited treatment options. Here, we characterize the biological functions of a novel gene, abrp, which encodes a peptidase C13 family. We demonstrate that the abrp is associated with decreased susceptibility to tetracycline, minocycline, doxycycline, tigecycline, chloramphenicol and fosfomycin. Deletion of abrp was able to increase cell membrane permeability and display slower cell growth rate. Results from the present study show that abrp plays an important role in conferring reduced susceptibility to different classes of antibiotics and cell growth in A. baumannii. The change of antibiotic sensitivities may result from modifications to the cell membrane permeability of A. baumannii. PMID:27220329

  18. Effects of chloramphenicol on brain energy metabolism using 31P spectroscopy: influences on sleep-wake states in rat.

    Science.gov (United States)

    Chahboune, Halima; Mahdjoub, Rachid; Desgoutte, Pierre; Rousset, Colette; Briguet, André; Cespuglio, Raymond

    2008-08-01

    Effects of chloramphenicol (antibiotic inhibiting complex-1 of respiratory chain) and thioamphenicol (TAP, a structural analog of CAP inactive on complex-1) were examined on cerebral energy metabolites and sleep-wake cycle architecture in rat. In the first group, animals were chronically equipped with a cranial surface resonator and (31)P spectroscopic measurements were performed using a 2 T magnetic resonance spectrometer (operating frequency 34.46 MHz). CAP administration (400 mg/kg, tail vein, light period) induced deficits in phosphocreatine (-30%, p electrodes for EEG and electromyogram recordings. CAP administered intraperitoneally at light-onset reduced rapid-eye movement (REM) sleep (-60% in the first 6 h of light period, p EEG were, respectively, increased and decreased (p EEG. Overall, these data indicate that REM sleep occurrence is linked to an aerobic production of ATP. PMID:18507739

  19. In vitro activity of pipecolic acid amide of clindamycin (U-57930E) on anaerobic bacteria compared with those of clindamycin, cefoxitin, and chloramphenicol.

    OpenAIRE

    Dhawan, V K; Bansal, M B; Thadepalli, H

    1982-01-01

    In vitro activity of pipecolic acid amide of clindamycin (U-57930E) against 265 isolates of anaerobic bacteria, including 66 strains of Bacteroides fragilis, was compared with those of clindamycin, chloramphenicol, and cefoxitin. At therapeutically achievable concentrations, the activities of all four antibiotics against anaerobic bacteria were similar.

  20. Evaluation of matrix effect in isotope dilution mass spectrometry based on quantitative analysis of chloramphenicol residues in milk powder

    International Nuclear Information System (INIS)

    Graphical abstract: -- Highlights: •We develop a strategy to evaluate matrix effect and its impact on the IDMS results. •Matrix effect and IDMS correction factor from different conditions are evaluated. •Ion suppression effect is observed in LLE and HLB pre-treated sample solutions. •Ion enhancement effect is found in MCX pre-treated sample solution. •IDMS correction factor in HLB and MCX solutions in three instruments is close to 1 -- Abstract: In the present study, we developed a comprehensive strategy to evaluate matrix effect (ME) and its impact on the results of isotope dilution mass spectrometry (IDMS) in analysis of chloramphenicol (CAP) residues in milk powder. Stable isotope-labeled internal standards do not always compensate ME, which brings the variation of the ratio (the peak area of analyte/the peak area of isotope). In our investigation, impact factors of this variation were studied in the extraction solution of milk powder using three mass spectrometers coupled with different ion source designs, and deuterium-labeled chloramphenicol (D5-CAP) was used as the internal standard. ME from mobile phases, sample solvents, pre-treatment methods, sample origins and instruments was evaluated, and its impact on the results of IDMS was assessed using the IDMS correction factor (θ). Our data showed that the impact of ME of mobile phase on the correction factor was significantly greater than that of sample solvent. Significant ion suppression and enhancement effects were observed in different pre-treated sample solutions. The IDMS correction factor in liquid–liquid extraction (LLE) and molecular imprinted polymer (MIP) extract with different instruments was greater or less 1.0, and the IDMS correction factor in hydrophilic lipophilic balance (HLB) and mix-mode cation exchange (MCX) extract with different instruments was all close to 1.0. To the instrument coupled with different ion source design, the impact of ME on IDMS quantitative results was

  1. Source identification and entry pathways of banned antibiotics nitrofuran and chloramphenicol in shrimp value chain of Bangladesh

    Directory of Open Access Journals (Sweden)

    M. Jakiul Islam

    2014-11-01

    Full Text Available Background: Contamination with residues of banned carcinogenic antibiotic drugs like nitrofuran metabolites and chloramphenicol (CAP in frozen shrimp products has become a major concern of food safety for exporting countries. In the present study an approach was taken to identify the sources of such harmful antibiotics in the shrimp value chain of Bangladesh, one of the major shrimp countries. Materials and Methods: Inputs of farms and hatchery systems including feed, feed additives, feed ingredients and therapeutic agents were thought to be the sources of contagion. Fish and shrimp feed, feed ingredients, sediment and water samples of shrimp hatcheries and farms were, therefore, analyzed for 3-Amino-5-morpholinomethyl-2-oxazolidinone (AMOZ, 3-Amino-2-oxazolidinone (AOZ, 1-Amino-hydantoin (AHD, Semicarbazide (SEM and chloramphenicol (CAP to identify their source and entry pathways. About 500 g of each 160 feed and feed ingredients were collected in pyrogens free polyethylene sealed bag and transported to Fish Inspection and Quality Control (FIQC laboratory, Dhaka, Bangladesh. Whereas 500 mL of each 250 soils and water sample were collected from hatcheries. Sample preparation and residual metabolites analysis were conducted using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS analytical assays on an Waters Alliance 2695 series HPLC and Quattro Micro, API mass spectrometer instrumentation (Waters Corporation, USA. Results: Among the analyzed 160 feed samples, 38 were found contaminated with CAP and/or nitrofuran metabolites (AMOZ, AOZ, AHD and SEM, where 11, 10, 8, and 9 samples were for shrimp feed, fish feed, poultry feed and feed ingredients. Imported feed ingredients contained with protein concentrates of improper quality were found contaminate with higher level of SEM. Although hatcheries were found free from contamination, whereas sediment and water samples of many shrimp farms were found contaminated with high levels of

  2. Evaluation of matrix effect in isotope dilution mass spectrometry based on quantitative analysis of chloramphenicol residues in milk powder

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiu Qin; Yang, Zong; Zhang, Qing He, E-mail: qhzhang204@gmail.com; Li, Hong Mei

    2014-01-07

    Graphical abstract: -- Highlights: •We develop a strategy to evaluate matrix effect and its impact on the IDMS results. •Matrix effect and IDMS correction factor from different conditions are evaluated. •Ion suppression effect is observed in LLE and HLB pre-treated sample solutions. •Ion enhancement effect is found in MCX pre-treated sample solution. •IDMS correction factor in HLB and MCX solutions in three instruments is close to 1 -- Abstract: In the present study, we developed a comprehensive strategy to evaluate matrix effect (ME) and its impact on the results of isotope dilution mass spectrometry (IDMS) in analysis of chloramphenicol (CAP) residues in milk powder. Stable isotope-labeled internal standards do not always compensate ME, which brings the variation of the ratio (the peak area of analyte/the peak area of isotope). In our investigation, impact factors of this variation were studied in the extraction solution of milk powder using three mass spectrometers coupled with different ion source designs, and deuterium-labeled chloramphenicol (D5-CAP) was used as the internal standard. ME from mobile phases, sample solvents, pre-treatment methods, sample origins and instruments was evaluated, and its impact on the results of IDMS was assessed using the IDMS correction factor (θ). Our data showed that the impact of ME of mobile phase on the correction factor was significantly greater than that of sample solvent. Significant ion suppression and enhancement effects were observed in different pre-treated sample solutions. The IDMS correction factor in liquid–liquid extraction (LLE) and molecular imprinted polymer (MIP) extract with different instruments was greater or less 1.0, and the IDMS correction factor in hydrophilic lipophilic balance (HLB) and mix-mode cation exchange (MCX) extract with different instruments was all close to 1.0. To the instrument coupled with different ion source design, the impact of ME on IDMS quantitative results was

  3. A sensitive fluorescent nanosensor for chloramphenicol based on molecularly imprinted polymer-capped CdTe quantum dots.

    Science.gov (United States)

    Amjadi, Mohammad; Jalili, Roghayeh; Manzoori, Jamshid L

    2016-05-01

    A novel fluorescent nanosensor using molecularly imprinted silica nanospheres embedded CdTe quantum dots (CdTe@SiO2 @MIP) was developed for detection and quantification of chloramphenicol (CAP). The imprinted sensor was prepared by synthesis of molecularly imprinting polymer (MIP) on the hydrophilic CdTe quantum dots via reverse microemulsion method using small amounts of solvents. The resulting CdTe@SiO2 @MIP nanoparticles were characterized by fluorescence, UV-vis absorption and FT-IR spectroscopy and transmission electron microscopy. They preserved 48% of fluorescence quantum yield of the parent quantum dots. CAP remarkably quenched the fluorescence of prepared CdTe@SiO2 @MIP, probably via electron transfer mechanism. Under the optimal conditions, the relative fluorescence intensity of CdTe@SiO2 @MIP decreased with increasing CAP by a Stern-Volmer type equation in the concentration range of 40-500 µg L(-1). The corresponding detection limit was 5.0 µg L(-1). The intra-day and inter-day values for the precision of the proposed method were all <4%. The developed sensor had a good selectivity and was applied to determine CAP in spiked human and bovine serum and milk samples with satisfactory results. PMID:27037966

  4. A novel biosensor based on competitive SERS immunoassay and magnetic separation for accurate and sensitive detection of chloramphenicol.

    Science.gov (United States)

    Yang, Kang; Hu, Yongjun; Dong, Ning

    2016-06-15

    The accurate and sensitive detection of chloramphenicol (CAP) is particularly imperative to public health and safety. Here, we present a novel sensor for residual CAP detection based on competitive surface-enhanced Raman scattering (SERS) immunoassay and magnetic separation. In this nanosensor, functionalized Au nanoparticles (AuNPs) were labeled with the Raman reporter molecule (e.g. 4,4'-dipyridyl). With the addition of free CAP, a competitive immune reaction was initiated between free CAP and above AuNPs for conjugating with CAP antibody-modified magnetic nanoparticles (MNPs). Instead of the solid substrate, the antibody conjugated-magnetic beads were used as supporting materials and separation tools in the present sensor. With the aid of a magnet, the mixture was removed from the supernatant for concentration effects. This caused obvious change of SERS signal intensity obtained from supernatant. The SERS signals were collected from the supernatant directly, which made the SERS measurements more stable, repeatable and reliable. The proposed SERS-based magnetic immunosensor allows us to detect CAP in a fast, selective and sensitive (1.0 pg/mL) manner over a wide concentration range ( 1-1 × 10(4)pg/mL). In addition, these results demonstrate that this immunosensor holds great potential for the detection of antibiotics in real aquatic environment, which is crucial to our life. PMID:26866562

  5. Development of Suberin Fatty Acids and Chloramphenicol-Loaded Antimicrobial Electrospun Nanofibrous Mats Intended for Wound Therapy.

    Science.gov (United States)

    Tamm, Ingrid; Heinämäki, Jyrki; Laidmäe, Ivo; Rammo, Liisi; Paaver, Urve; Ingebrigtsen, Sveinung G; Škalko-Basnet, Nataša; Halenius, Anna; Yliruusi, Jouko; Pitkänen, Pauliina; Alakurtti, Sami; Kogermann, Karin

    2016-03-01

    Suberin fatty acids (SFAs) isolated from outer birch bark were investigated as an antimicrobial agent and biomaterial in nanofibrous mats intended for wound treatment. Electrospinning (ES) was used in preparing the composite nonwoven nanomats containing chloramphenicol (CAM; as a primary antimicrobial drug), SFAs, and polyvinylpyrrolidone (as a carrier polymer for ES). The X-ray powder diffraction, differential scanning calorimetry, scanning electron microscopy, atomic force microscopy, and texture analysis were used for the physicochemical and mechanical characterization of the nanomats. ES produced nanofibrous mats with uniform structure and with an average fiber diameter ranging from 370 to 425 nm. Microcrystalline SFAs and crystalline CAM were found to undergo a solid-state transformation during ES processing. The ES process caused also the loss of CAM in the final nanofibers. In the texture analysis, the SFAs containing nanofibers exhibited significantly higher maximum detachment force to an isolated pig skin (p nanofibers. CAM exists in an amorphous form in the nanofibers which needs to be taken into account in controlling the physical storage stability. In conclusion, homogeneous composite nanofibrous mats for wound healing can be electrospun from the ternary mixture(s) of CAM, SFAs, and polyvinylpyrrolidone. PMID:26886306

  6. A label-free photoelectrochemical aptasensor based on nitrogen-doped graphene quantum dots for chloramphenicol determination.

    Science.gov (United States)

    Liu, Yong; Yan, Kai; Okoth, Otieno Kevin; Zhang, Jingdong

    2015-12-15

    A photoelectrochemical (PEC) sensing platform for chloramphenicol (CAP) detection was constructed using nitrogen-doped graphene quantum dots (N-GQDs) as transducer species and label-free aptamer as biological recognition element. N-GQDs, synthesized via a facile one-step hydrothermal method, were explored to achieve highly efficient photon-to-electricity conversion under visible light irradiation. The obtained N-GQDs were characterized by transmission electron microscopy (TEM), which displayed a narrow size distribution with a mean diameter of 2.14 nm. The X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared spectroscopic (FT-IR) analysis confirmed that nitrogen was successfully doped in GQDs. The UV-visible absorption spectra indicated that nitrogen doping obviously enhanced the absorption of GQDs in visible light region. As a result, the PEC activity of GQDs was promoted by nitrogen doping. Additionally, the π-conjugated structure of N-GQDs provided an excellent platform for aptamer immobilization via π-π stacking interaction. Such an aptamer/N-GQDs based sensor showed a linear PEC response to CAP concentration in the range of 10-250 nM with a detection limit (3 S/N) of 3.1 nM. The developed PEC aptasensor exhibited high sensitivity and selectivity, good reproducibility and high stability. PMID:26264269

  7. Studies on the antagonistic action between chloramphenicol and quinolones with presence of bovine serum albumin by fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu Baosheng, E-mail: lbs@hbu.edu.c [Key Laboratory of Medical Chemistry and Molecular Diagnosis, Ministry of Education, Center of Physics and Chemistry, Hebei University, Baoding 071002 (China); Zhao Fengli; Xue Chunli; Wang Jing; Lu Yunkai [Key Laboratory of Medical Chemistry and Molecular Diagnosis, Ministry of Education, Center of Physics and Chemistry, Hebei University, Baoding 071002 (China)

    2010-05-15

    Chloramphenicol (CHL) and quinolone drugs like ofloxacin (OFLX), lomefloxacin (LMX) and ciprofloxacin (CPFX) can all quench the fluorescence of bovine serum albumin (BSA) in the aqueous solution of pH=7.40. This quenching effect becomes more significant when CHL and quinolone drugs coexist. Based on this, further studies on the interactions between CHL and quinolone drugs using fluorescence spectrum are established. The results showed that the interaction between the drugs would increase the binding constant and binding stability of the drug and protein, thus reducing the amount of drugs transported to their targets. Therefore, free drug concentration at targets would decrease, reducing the efficacy of the drugs. It indicated that there exists antagonistic action between drugs. The results also showed that the quenching mechanism of BSA by the drugs is a static procedure. The number of binding sites is 1 in various systems. Due to the existence of the antagonistic action between drugs, the binding distance r is reduced. Studies utilizing synchronous spectra showed that the antagonistic action between the drugs would affect the conformation of BSA, making protein molecules extend and hydrophobic decrease. The order of antagonistic action between CHL and quinolone drugs is: CPFX>OFLX>LMX with presence of BSA.

  8. Electrochemical degradation of chloramphenicol with a novel Al doped PbO2 electrode: Performance, kinetics and degradation mechanism

    International Nuclear Information System (INIS)

    Highlights: • A novel Al doped PbO2 electrode was successfully prepared. • Electrochemical method is proved to be a useful way for the treatment of CAP. • The CAP degradation mechanism was discussed and a possible reaction pathway was proposed. - Abstract: This study presents an electrochemical method for the degradation of chloramphenicol (CAP) in aqueous solution with a novel Al doped PbO2 electrode. The Al-doped PbO2 electrode showed high electrochemical activity, oxygen evolution potential, radical utilization rate, reusability and safety. The influence factors on CAP degradation with the Al-doped PbO2 electrode were investigated in detail, and under the optimal conditions the removal rates of CAP and TOC reached 87.30% and 52.06% in acid conditions after 2.5 h electrolysis with a 0.2 mol dm−3 Na2SO4 at a current density of 30 mA cm−2, respectively. The electrochemical degradation of CAP at Al-doped PbO2 electrode electrode followed pseudo-first-order kinetics. The degradation mechanism was proposed by cyclic voltammograms tests and it was deduced that hydroxyl radicals generated in the electrochemical process played a key role in oxidizing CAP. Finally, based on the reaction products identified, a possible degradation pathway including radical reaction, ring open and mineralization was proposed

  9. Label-free and sensitive aptasensor based on dendritic gold nanostructures on functionalized SBA-15 for determination of chloramphenicol.

    Science.gov (United States)

    Bagheri Hashkavayi, Ayemeh; Raoof, Jahan Bakhsh; Azimi, Razieh; Ojani, Reza

    2016-04-01

    A highly sensitive and low-cost electrochemical aptasensor was developed for the determination of chloramphenicol (CAP). The system was based on a CAP-binding aptamer, a molecular recognition element, and 1,4-diazabicyclo[2.2.2]octane (DABCO)-supported mesoporous silica SBA-15 on the surface of a screen-printed graphite electrode for formation of dendritic gold nanostructures and improving the performance and conductivity of the biosensor. Hemin has been applied as an electrochemical indicator which interacted with the guanine bases of the aptamer. In the absence of CAP, hemin binds to the aptamer and produces a weak differential pulse voltammetric (DPV) signal. The presence of CAP led to stabilization of the folded aptamer, which generated an amplified DPV signal. The peak current of hemin increased linearly with the concentration of CAP. Under optimal conditions, two linear ranges were obtained from 0.03 to 0.15 μM and 0.15 to 7.0 μM, respectively, and the detection limit was 4.0 nM. The prepared biosensor has good selectivity against other non-target drugs. Thus, the sensor could provide a promising platform for the fabrication of aptasensors. The feasibility of using this aptasensor was demonstrated by determination of CAP in a human blood serum sample. PMID:26879648

  10. Determination of oxytetracycline, tetracycline and chloramphenicol antibiotics in animal feeds using subcritical water extraction and high performance liquid chromatography.

    Science.gov (United States)

    Wang, Linling; Yang, Hai; Zhang, Chunwei; Mo, Yulin; Lu, Xiaohua

    2008-06-30

    A rapid analytical method for the determination of oxytetracycline (OTC), tetracycline (TC) and chloramphenicol (CAP) antibiotics in animal feeds has been developed based on subcritical water extraction (SWE) without further sample clean-up followed by high performance liquid chromatography (HPLC) with ultraviolet (UV) detection. On extracting target antibiotics from spiked samples, the efficiency of the water extraction device was evaluated in terms of pH and volume of the extractant, temperature and time of the static extraction. The best extraction conditions were obtained by using 5.5 mL of water adjusted to pH 2 with hydrochloric acid as the extractant at 100 degrees C with 5-min static extraction. After filtration, 20 microL of the aqueous extract was directly injected into the HPLC column. Recoveries between 82.1% and 90.0% with relative standard deviations ranging between 1.6% and 4.8% were achieved from spiked animal feed samples by using this method. Compared with the traditional ultrasonic extraction, this procedure was remarkably more efficient in extracting OTC, TC and CAP, simpler to perform, and there was no use of toxic organic solvents. PMID:18539174

  11. An aptamer-based colorimetric assay for chloramphenicol using a polymeric HRP-antibody conjugate for signal amplification

    International Nuclear Information System (INIS)

    We describe an aptamer-based colorimetric assay for chloramphenicol (CAP) based on the ability of anti-single-stranded DNA antibody (anti-ssDNA Ab) to recognize ssDNA, and the catalytic ability of PowerVision (PV), which is a polymeric conjugate of horseradish peroxidase and antibody with a high enzyme-to-antibody ratio. The complementary DNA of the aptamer (cDNA) was immobilized on magnetic gold nanoparticles (Fe3O4-Au) and used as a capture probe (AuMNPs-cDNA). The ssDNA Ab and PV were conjugated to AuNPs to form signal tags that recognize ssDNA with anti-ssDNA Ab to form beads containing the amplified probe (AuMNPs-cDNA-anti-ssDNA Ab/PV-AuNPs). The PV on their surface catalyzes the oxidation of the substrate 3,3’,5,5’-tetramethylbenzidine to produce a color change which is quantified by absorptiometry at 652 nm. The assay has a linear calibration plot for CAP in the 0.01 to 100 ng mL−1 range, with a detection limit as low as 3 pg mL−1. The method was successfully employed to detect CAP in real samples. Results were consistent with data obtained using a conventional enzyme-linked immunosorbent assay. (author)

  12. Enhanced activity of streptomycin and chloramphenicol against intracellular Escherichia coli in the J774 macrophage cell line mediated by liposome delivery.

    OpenAIRE

    Stevenson, M.; Baillie, A. J.; Richards, R M

    1983-01-01

    Streptomycin and chloramphenicol were entrapped within large neutral or anionic unilamellar vesicles of egg phosphatidylcholine prepared by an ether injection method. Both antibiotics in liposomal form were inactive against Escherichia coli in a simple tube dilution assay. A comparison was made of the activities of the free and liposomal forms of the antibiotics against E. coli located within the macrophages of the J774.2 murine cell line. The apparent intracellular antibacterial activity of ...

  13. Simultaneous detection of metronidazole and chloramphenicol by differential pulse stripping voltammetry using a silver nanoparticles/sulfonate functionalized graphene modified glassy carbon electrode

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted -- Highlights: • A novel and reliable AgNPs/SF-GR modified glassy carbon electrode was constructed and characterized. • The AgNPs/SF-GR/GCE was successfully applied in the shrimp for simultaneous determination of MTZ and CAP. • Under optimized conditions, common substances such as UA, AA, DA and ion did not interfered in the electrode performance. • The modified electrode exhibited considerable sensitivity, stability and reproducibility. • This fabricated electrode achieved a satisfactory level compared with other electrodes toward MTZ and CAP. -- Abstract: A novel silver nanoparticles/sulfonated functionalized graphene modified glassy carbon electrode (AgNPs/SF-GR/GCE) was fabricated to determine chloramphenicol and metronidazole simultaneously. Taking advantage of sulfonic group, AgNPs were successfully electrodeposited on functionalized GR immobilized on the surface of a GCE. Scanning electron microscopy and energy spectrum analysis results confirmed that AgNPs were deposited on the functionalized GR film. Compared to the bare GCE or the pristine SF-GR modified electrode, AgNPs/SF-GR/GCE exhibited excellent electroreduction towards chloramphenicol and metronidazole. In addition, the two antibacterial drugs were separated completely in 0.10 M citric acid-sodium citrate buffer (pH 4.0) by differential pulse stripping voltammetry under optimum conditions. The cathodic current was linearly related with 0.02∼20.0 μM chloramphenicol and 0.10∼20.0 μM metronidazole, with the detection limits of 0.01 μM and 0.05 μM respectively. Furthermore, AgNPs/SF-GR/GCE was applied to the simultaneous determination of chloramphenicol and metronidazole in an aquatic product

  14. Research Progress on Detection of Chloramphenicol by Liquid Chromatography in Animal Derived Food%液相色谱法检测畜禽食品中氯霉素残留研究进展

    Institute of Scientific and Technical Information of China (English)

    孙情; 王宝维; 张乐乐

    2011-01-01

    Chloramphenicol as a commonly used broad-spectrum antibiotics with optical activity has been widely used in animal husbandry. However, excessive use of chloramphenicol during animal growth would lead to chloramphenicol residues in animal derived food, which cause great harm to human. All countries in the world focus on the detection of chloramphenicol residues in animal derived food. This article describes the dangers of chloramphenicol and maximum residue limits of different countries and reviews the research progress on liquid chromatography applied to detect chloramphenicol residues in animal derived food.%氯霉素是一种常用的具有旋光活性的广谱抗生素,广泛应用于畜牧业中。然而,动物生长过程中过量使用氯霉素会导致其在动物源性食品中残留,给人体健康带来极大的危害。世界各国对动物源性食品中氯霉素残留的监控愈来愈严格,对各种检测方法也提出了越来越高的要求。本文对氯霉素的危害、氯霉素使用限量标准及液相色谱法检测其在畜禽食品中的残留进行综述。

  15. Effects of chloramphenicol preconditioning on oxidative respiratory function of cerebral mitochondria in rats exposed to acute hypoxia

    Institute of Scientific and Technical Information of China (English)

    陈丽峰; 柳君泽; 党永明; 宋熔

    2004-01-01

    Objective: To investigate the roles of chloramphenicol (CAP) preconditioning in the oxidative respiratory function of cerebral mitochondria in rats exposed to acute hypoxia during acute hypoxia by observing the changes of mitochondrial oxidative respiratory function and cytochrome C oxidase (COX) activity. Methods: Adult male Wistar rats were randomly divided into 4 groups: control (C), medication (M), hypoxia (H), and medication plus hypoxia (MH). Rats in groups M and MH were administered by peritoneal injection of CAP (50 mg/kg) every 12 h for 7 d before decapitation, but those in groups H and MH were exposed to a hypobaric chamber simulating 5 000 m high altitude for 24 h. The rat cerebral cortex was removed and mitochondria were isolated by centrifugation. Mitochondrial respiratory function and COX activity were measured by Clark oxygen electrode. Results: Compared with Group C, Group H showed significantly elevated state 4respiration (ST4), decreased state 3 respiration (ST3), and respiratory control rate (RCR) in mitochondrial respiration during acute hypoxic exposure. ST3 in Group MH was significantly lower than that in Group C, but was not significantly different from that in Groups H and M, while ST4 in Group MH was significantly lower than that in groups C and H. RCR in Group MH was higher than that in Group H, but lower than that in Group C. COX activity in Group H was significantly lower than that in Group C. In Group MH, COX activity increased and was higher than that in Group H, but was still lower than that in Group C. Conclusion: Acute hypoxic exposure could lead to mitochondrial respiratory dysfunction, suggesting that CAP preconditioning might be beneficial to the recovery of rat respiratory finction. The change of COX activity is consistent with that of mitochondrial respiratory function during acute hypoxic exposure and CAP-administration, indicating that COX plays an important role in oxidative phosphorylation function of mitochondria from

  16. Enhancing chloramphenicol and trimethoprimin vitro activity byOcimum sanctum Linn. (Lamiaceae) leaf extract againstSalmonellaenterica serovar Typhi

    Institute of Scientific and Technical Information of China (English)

    Shyamapada Mandal; Manisha Deb Mandal; Nishith Kumar Pal

    2012-01-01

    Objective:To evaluate the antibacterial activity ofOcimum sanctum (O. sanctum) leaf extract, alone, and in combination with chloramphenicol (C) and trimethoprim (Tm) againstSalmonella enterica serovar Typhi (S. typhi).Methods: The antibacterial activity of ethanolic extract of tulsi, O. sanctum, leaf(TLE; 500 μg) for23S. typhi isolates was determined following agar diffusion. TheC (30 μg) and Tm (5 μg) activity alone and in combination with TLE(250 μg) was determined by disk diffusion. The zone diameter of inhibition(ZDI)for the agents was recorded, and growth inhibitory indices (GIIs) were calculated.Results: The S. typhi isolates (n=23), which were resistant to bothC (ZDI 6 mm) and Tm (ZDI6 mm), hadTLE (500 μg)ZDIs16-24 mm. The ZDIs ofC and Tm were increased up to15-21 mm and 17-23 mm, respectively, whenTLE(250 μg) was added to theC and Tm discs. TheGIIs ranged0.789-1.235 and0.894-1.352, due to combined activity againstS. typhi isolates, ofC andTLE and Tm andTLE, respectively.Conclusions: The data suggest that TLE, in combination with C and Tm, had synergistic activity forS. typhi isolates, and henceO. sanctumis potential in combatingS. typhi drug resistance, as well promising in the development of non-antibiotic drug forS. typhi infection.

  17. Determination of chloramphenicol, thiamphenicol, florfenicol and florfenicol amine in poultry, swine, bovine and fish by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Barreto, Fabiano; Ribeiro, Cristina; Barcellos Hoff, Rodrigo; Dalla Costa, Teresa

    2016-06-01

    A simple, rapid and sensitive method for confirmatory and quantitative purposes using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was developed and validated for determination of chloramphenicol, thiamphenicol, florfenicol and its metabolite, florfenicol amine, in poultry, swine, bovine and fish muscle. Sample preparation was based on extraction with organic solvent (ethyl acetate: ammonium hydroxide, 98:2) followed by evaporation and fat removal using hexane. The chromatographic separation was carried out with an XTerra C18 column with a gradient elution using water and acetonitrile both with 2mM of ammonium acetate. Mass spectrometry with electrospray ionization was operated in positive or negative polarity using selected-reaction monitoring (SRM) analysis mode, achieving the requirements of four identification points for each compound. Chloramphenicol-D5 was added as internal standard. Method validation was performed according to the criteria of Commission Decision 2002/657/EC. Parameters as precision, reproducibility, trueness, CCα and CCβ were determined. Trueness values were within the range 82-108% and 84-111% for bovine and fish, respectively. Precision ranged from 1.1% to 10.1% and within-laboratory reproducibility ranged from 4.3 to 18.1%, depending on matrix. The CCα and CCβ for bovine muscle, for instance, were established as 0.06 and 0.11μgkg(-1), respectively. The method was successfully applied for several interlaboratory proficiency testing programs, achieving 100% of satisfactory results. PMID:27133862

  18. 水杨酸氯霉素醇溶液的质量控制%Quality control of preparation of salicylic acid and chloramphenicol alcoholic solution

    Institute of Scientific and Technical Information of China (English)

    赵子瑞; 张迅; 张佳莉; 董敏; 李云兰

    2013-01-01

    目的 建立水杨酸氯霉素醇溶液的质量控制方法.方法 采用酸碱滴定法测定水杨酸的含量,化学法鉴别其中的水杨酸和氯霉素,装量差异应符合涂剂项下有关的各项规定.结果 3批样品化学鉴别均呈阳性反应,阴性对照不干扰测定.水杨酸含量测定线性范围为80.0~402.5 mg,回归方程为=15.0803x+1.2704,r=0.9996,平均回收率为99.6%,RSD为0.4%(n=6).结论 本法简便灵敏,重复性好,专属性强,能有效控制水杨酸氯霉素醇溶液的质量.%Objective To establish a methodology for quality control of preparation of salicylic acid and chloramphenicol alcoholic solution. Methods The acid-base titration was employed to determine the content of salicylic acid, and miscellaneous chemical methods were applied to identify salicylic acid and chloramphenicol. The difference in volume conformed to relevant regulations. Results The three batches of samples tested positively without interference on the negative control. Determination of salicylic acid yielded a linear range of 80~402.5 mg, the regression e-quation of y=15.0803χ+1.2704 (r=0.9996), with the average recovery of 99.6% and RSD of 0.4% (n=6). Conclusion Owing to high sensitivity repeatability and specificity, the aforementioned methodology may effectively secure the quality of salicylic acid and chloramphenicol alcoholic solution.

  19. Insight into the secondary structure of chloramphenicol acetyltransferase type I — computer analysis and FT-IR spectroscopic characterization of the protein structure

    Science.gov (United States)

    Andreeva, A. E.; Karamancheva, I. R.

    2001-05-01

    The secondary structure of chloramphenicol O-acetyltransferase type I (CAT I) and an N-terminal deleted mutant has been studied by Fourier transform infrared spectroscopy. The analysis of the amide I band of different samples (KBr, hydrated films and buffer solution) by Fourier self-deconvolution followed by a curve fitting was performed. The spectroscopic data have been utilized to determine the α-helix and β-structure % contents, which depend strongly on the protein sample preparation. Furthermore, the secondary structure of the enzyme-inhibitor Crystal Violet complex was analyzed. The observed difference in the secondary structural contents suggests that some conformational changes of the enzyme are induced by the inhibitor after binding.

  20. Method for Regulated Expression of Single-Copy Efflux Pump Genes in a Surrogate Pseudomonas aeruginosa Strain: Identification of the BpeEF-OprC Chloramphenicol and Trimethoprim Efflux Pump of Burkholderia pseudomallei 1026b

    OpenAIRE

    Kumar, Ayush; Chua, Kim-Lee; Schweizer, Herbert P.

    2006-01-01

    Construction and integration of recombinant mini-Tn7 expression vectors into the chromosome of a surrogate, efflux-sensitized, and biosafe Pseudomonas aeruginosa host was validated as a generally applicable method for studies of uncharacterized bacterial efflux pumps. Using this method, the Burkholderia pseudomallei bpeEF-oprC operon was shown to encode a chloramphenicol and trimethoprim efflux pump.

  1. Simultaneous detection for three kinds of veterinary drugs: Chloramphenicol, clenbuterol and 17-beta-estradiol by high-throughput suspension array technology

    Energy Technology Data Exchange (ETDEWEB)

    Liu Nan; Su Pu [Institute of Hygiene and Environmental Medicine, Tianjin 300050 (China); Gao Zhixian [Institute of Hygiene and Environmental Medicine, Tianjin 300050 (China)], E-mail: gaozhx@163.com; Zhu Maoxiang; Yang Zhihua; Pan Xiujie [Institute of Radiation Medicine, Beijing 100850 (China); Fang Yanjun; Chao Fuhuan [Institute of Hygiene and Environmental Medicine, Tianjin 300050 (China)

    2009-01-19

    Suspension array technology for simultaneous detection of three kinds of veterinary drugs, chloramphenicol (CAP), clenbuterol and 17-beta-estradiol has been developed. Conjugates of chloramphenicol and clenbuterol coupled with bovine serum albumin were synthesized and purified. Probes of suspension array were constituted by coupling the three conjugates on the fluorescent microspheres/beads and the microstructures of the beads' surface were observed by scanning electron microscopy which was a direct confirmation for the successful conjugates' coupling. The optimal addition of conjugates and the amounts of antibodies were optimized and selected, respectively. Standard curves were plotted and the coefficient of determination-R{sup 2} was greater than 0.989 which suggested good logistic correlation. The detection ranges for the three veterinary drugs are 40-6.25 x 10{sup 5} ng L{sup -1}, 50-7.81 x 10{sup 5} ng L{sup -1} and 1 x 10{sup 3-}7.29 x 10{sup 5} ng L{sup -1}, respectively and the lowest detection limits (LDLs) of them are 40, 50 and 1000 ng L{sup -1}, respectively. The suspension array is specific and has no significant cross-reactivity with other chemicals. Meanwhile, unknown samples were detected by suspension array and ELISA in comparison with each other. The errors between found and real for the detection of the unknown samples were relatively small to both of the two methods, whereas, the detection ranges of suspension array are broader and sensitive than that of the traditional ELISA. The high-throughput suspension array is proved to be a novel method for multi-analysis of veterinary drugs with simple operation, high sensitivity and low cost.

  2. Simultaneous detection for three kinds of veterinary drugs: Chloramphenicol, clenbuterol and 17-beta-estradiol by high-throughput suspension array technology

    International Nuclear Information System (INIS)

    Suspension array technology for simultaneous detection of three kinds of veterinary drugs, chloramphenicol (CAP), clenbuterol and 17-beta-estradiol has been developed. Conjugates of chloramphenicol and clenbuterol coupled with bovine serum albumin were synthesized and purified. Probes of suspension array were constituted by coupling the three conjugates on the fluorescent microspheres/beads and the microstructures of the beads' surface were observed by scanning electron microscopy which was a direct confirmation for the successful conjugates' coupling. The optimal addition of conjugates and the amounts of antibodies were optimized and selected, respectively. Standard curves were plotted and the coefficient of determination-R2 was greater than 0.989 which suggested good logistic correlation. The detection ranges for the three veterinary drugs are 40-6.25 x 105 ng L-1, 50-7.81 x 105 ng L-1 and 1 x 103-7.29 x 105 ng L-1, respectively and the lowest detection limits (LDLs) of them are 40, 50 and 1000 ng L-1, respectively. The suspension array is specific and has no significant cross-reactivity with other chemicals. Meanwhile, unknown samples were detected by suspension array and ELISA in comparison with each other. The errors between found and real for the detection of the unknown samples were relatively small to both of the two methods, whereas, the detection ranges of suspension array are broader and sensitive than that of the traditional ELISA. The high-throughput suspension array is proved to be a novel method for multi-analysis of veterinary drugs with simple operation, high sensitivity and low cost

  3. The effects of chloramphenicol and 60Co irradiation on the experimental mycosis in mice inoculated intragastrically with two kinds of pathogenic yeast-like fungi

    International Nuclear Information System (INIS)

    Two kinds of pathogenic yeast, Cryptococcus neoformans and Candida albicans were inoculated into the stomachs of mice. The effects of intragastric administration of chloramphenicol (CM) and systemic irradiation with 60Co on the acceralation of infection were studied in intragastrically inoculated mice. When Cryptococcus neoformans were simply inoculated, it was difficult for them to reside in the alimentary canal to cause infection. In case of candida albicans inoculated simply, they were also unable to induce infection though they remained in the alimentary canal for a long time. In the experiment combining intragastric administration of the fungi and CM some mice contracted the disease and died. The effect of CM in causing infection was not proved. In the experiments combining 60Co irradiation and intragastric administration of CM and fungi, a high incidence of fungus infection was noted with both Cryptococcus neoformans and Candida albicans. Fungus lesions were observed in many organs, and in all of the mice which died systemic fungus lesions were noted. It was shown that systemic irradiation with 60Co had a specific effect on facilitating the infection. In these studies no difference was observed in the incidence of the fungus disease in respect of the origin of the causative fungi. (J.P.N.)

  4. In situ solvothermal growth of metal-organic framework-ionic liquid functionalized graphene nanocomposite for highly efficient enrichment of chloramphenicol and thiamphenicol.

    Science.gov (United States)

    Wu, Mian; Ai, Youhong; Zeng, Baizhao; Zhao, Faqiong

    2016-01-01

    Here we report a facile in situ solvothermal growth method for immobilization of metal-organic framework-ionic liquid functionalized graphene (MOF-5/ILG) composite on etched stainless steel wire. The X-ray diffraction spectra, scanning electron microscopy and transmission electron microscopy images showed that the metal organic framework possessed good crystal shape and its structure was not disturbed by the introduction of ILG. Moreover, the covalent bond established between the amino group of ILG and the carboxylic group of the metal organic framework improved the mechanical stability and structure uniformity of the microcrystals. The obtained material combined the favorable attributes of both metal-organic framework and ILG, having high surface area (820 m(2)/g) and good adsorption capability. Its adsorption properties were explored by preconcentrating chloramphenicol and thiamphenicol from aqueous solutions prior to gas chromatography-flame ionization detection. The MOF-5/ILG exhibited high enrichment capacity for the analytes as they could interact through π-π and H-bonding interaction. Under the optimum conditions, good linearity (correlation coefficients higher than 0.9981), low limits of detection (14.8-19.5 ng/L), and good precision (relative standard deviations less than 6.0% (n=5)) were achieved. The MOF-5/ILG composite displayed durable property. The method was applied to the determination of two antibiotics in milk, honey, urine and serum samples with acceptable relative recoveries of 82.3-103.2%. PMID:26686562

  5. Detection and quantification of chloramphenicol in milk and honey using molecularly imprinted polymers: Canadian penny-based SERS nano-biosensor.

    Science.gov (United States)

    Gao, Fang; Feng, Shaolong; Chen, Zhiwen; Li-Chan, Eunice C Y; Grant, Edward; Lu, Xiaonan

    2014-12-01

    We integrated molecularly imprinted polymers with surface-enhanced Raman spectroscopy (MIPs-SERS) to develop an innovative nano-biosensor for the determination of chloramphenicol (CAP) in milk and honey products. Template molecule (CAP), functional monomer (acrylamide), cross-linking agent (ethylene glycol dimethacrylate), initiator (2,2'-azobis(isobutyronitrile)), and porogen (methanol) were employed to form MIPs via "dummy" precipitation polymerization. Static and kinetic studies validated the specific selectivity of MIPs toward CAP over nonimprinted polymers (imprinting factor >4). Canadian penny-based silver nano-structure was synthesized as SERS-active substrate for determination of CAP in food matrices. Collected spectra were processed by principal component analysis to differentiate various concentrations of CAP in foods. Partial least squares regression models showed good prediction values (R > 0.9) of actual spiked contents (0, 0.1, 0.5, 1, 5 ppm) of CAP in milk and honey. This developed nano-biosensor is low cost, requires little sample pretreatment, and can provide reliable detection of trace level of chemical hazards in food systems within a total of 15 min. PMID:25393060

  6. Separation, concentration and determination of chloramphenicol in environment and food using an ionic liquid/salt aqueous two-phase flotation system coupled with high-performance liquid chromatography.

    Science.gov (United States)

    Han, Juan; Wang, Yun; Yu, Cuilan; Li, Chunxiang; Yan, Yongsheng; Liu, Yan; Wang, Liang

    2011-01-31

    Ionic liquid-salt aqueous two-phase flotation (ILATPF) is a novel, green, non-toxic and sensitive samples pretreatment technique. ILATPF coupled with high-performance liquid chromatography (HPLC) was developed for the analysis of chloramphenicol, which combines ionic liquid aqueous two-phase system (ILATPS) based on imidazolium ionic liquid (1-butyl-3-methylimidazolium chloride, [C(4)mim]Cl) and inorganic salt (K(2)HPO(4)) with solvent sublation. In ILATPF systems, phase behaviors of the ILATPF were studied for different types of ionic liquids and salts. The sublation efficiency of chloramphenicol in [C(4)mim]Cl-K(2)HPO(4) ILATPF was influenced by the types of salts, concentration of K(2)HPO(4) in aqueous solution, solution pH, nitrogen flow rate, sublation time and the amount of [C(4)mim]Cl. Under the optimum conditions, the average sublation efficiency is up to 98.5%. The mechanism of ILATPF contains two principal processes. One is the mechanism of IL-salt ILATPS formation, the other is solvent sublation. This method was practical when applied to the analysis of chloramphenicol in lake water, feed water, milk, and honey samples with the linear range of 0.5-500 ng mL(-1). The method yielded limit of detection (LOD) of 0.1 ng mL(-1) and limit of quantification (LOQ) of 0.3 ng mL(-1). The recovery of CAP was 97.1-101.9% from aqueous samples of environmental and food samples by the proposed method. Compared with liquid-liquid extraction, solvent sublation and ionic liquid aqueous two-phase extraction, ILATPF can not only separate and concentrate chloramphenicol with high sublation efficiency, but also efficiently reduce the wastage of IL. This novel technique is much simpler and more environmentally friendly and is suggested to have important applications for the concentration and separation of other small biomolecules. PMID:21168562

  7. 氯霉素单克隆抗体的制备与纯化%Preparation and purification of monoclonal antibodies against chloramphenicol

    Institute of Scientific and Technical Information of China (English)

    易喻; 汪竹环; 朱克寅; 李敏; 应国清

    2012-01-01

    目的 制备氯霉素(CAP)单克隆抗体.方法 用人工合成抗原氯霉素-牛血清白蛋白(CAP-BSA)免疫BALB/c小鼠,取其脾细胞与小鼠骨髓瘤细胞SP2/0按5:1的比例融合,间接竞争ELISA法和有限稀释法进行单克隆杂交瘤细胞的筛选;制备腹水抗体;采用HiTrap rProtein A FF亲和色谱柱纯化抗体,用间接竞争ELISA法和间接ELISA测定抗体特异性.结果 得到两株能稳定分泌单克隆抗体的杂交瘤细胞株,细胞培养上清中抗体效价达10-4以上,腹水抗体效价达10-7以上,纯化后的单克隆抗体纯度达98%,回收率达80%,抗体活性好并且与BSA、甲砜霉素、磺二甲基嘧啶等无交叉反应.结论 成功获得两株能稳定分泌单克隆抗体的杂交瘤细胞,对动物性食品中CAP的检测具有较大的价值.%Purpose To prepare monoclonal antibody against chloramphenicol ( CAP). Methods BALB/c mice were immunized with CAP-BSA,and spleen cells from the mice were fused with myeloma cells SP2/0 at ratio of 5:1. Monoclonal hybridomas were screened by competitive indirect enzyme-linked-immunoadsorbent assay ( ciELISA) and limited dilution. Mouse ascites were prepared by intraperitoneal injection of hybridoma cells. The ascites were purified by protein A affinity chromatography. Specificity and activity of the ascites antibody were determined by ciELISA and indirect ELISA. Results Two strains of hybridoma cell lines obtained could secrete McAb stably. The titre of Mab of cell culture supernate is more than 10 ,and the titre of prepared ascites Mab is more than 10 . After purification, the purity of the obtained monoclonal antibody was more than 98% and recovery reached 75% . There is no cross-activity between McAb against chloramphenicol and some compounds. Conclusion The two obtained strains of hybridoma cell lines can secrete McAb stably. The monoclonal antibodies can be used in the future research.

  8. Isolation and characterization of cyclo-(tryptophanyl-prolyl) and chloramphenicol from Streptomyces sp. SUK 25 with antimethicillin-resistant Staphylococcus aureus activity

    Science.gov (United States)

    Alshaibani, Muhanna M; Jalil, Juriyati; Sidik, Nik M; Edrada-Ebel, Ruangelie; Zin, Noraziah M

    2016-01-01

    Background Zingiber spectabile, commonly known as Beehive Ginger, is used as an ethnobotanical plant in many countries as an appetizer or to treat stomachache, toothache, muscle sprain, and as a cure for swelling, sores and cuts. This is the first report of isolation of Streptomyces strain from the root of this plant. Strain Universiti Kebangsaan 25 (SUK 25) has a very high activity to produce secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA), which is associated with high morbidity and mortality rates due to acquired multidrug resistance genes and causes medication failure in some clinical cases worldwide. Phylogenetic analysis based on the 16S ribosomal RNA gene sequence exhibited that the most closely related strain was Streptomyces omiyaensis NBRC 13449T (99.0% similarity). Aim This study was conducted to carry out the extraction, identification, and biological evaluation of active metabolites isolated from SUK 25 against three MRSA strains, namely, MRSA ATCC 43300, MRSA ATCC 33591, and MRSA ATCC 49476. Materials and methods The production of secondary metabolites by this strain was optimized through Thronton’s media. Isolation, purification, and identification of the bioactive compounds were carried out using reversed-phase high-performance liquid chromatography, high-resolution mass spectrometry, Fourier transform infrared, and one-dimensional and two-dimensional nuclear magnetic resonance. Results During screening procedure, SUK 25 exhibited good antimicrobial potential against several strains of MRSA. The best biological activity was shown from fraction number VII and its subfractions F2 and F3 with minimum inhibitory concentration values at 16 µg/mL and 8 µg/mL, respectively. These two subfractions were identified as diketopiperazine cyclo-(tryptophanyl-prolyl) and chloramphenicol. Conclusion On the basis of obtained results, SUK 25 isolated from Z. spectabile can be regarded as a new valuable source to produce secondary

  9. A homogeneous and "off-on" fluorescence aptamer-based assay for chloramphenicol using vesicle quantum dot-gold colloid composite probes.

    Science.gov (United States)

    Miao, Yang-Bao; Ren, Hong-Xia; Gan, Ning; Zhou, You; Cao, Yuting; Li, Tianhua; Chen, Yinji

    2016-07-27

    In this work, a novel homogeneous and signal "off-on" aptamer based fluorescence assay was successfully developed to detect chloramphenicol (CAP) residues in food based on the fluorescence resonance energy transfer (FRET). The vesicle nanotracer was prepared through labeling single stranded DNA binding protein (SSB) on limposome-CdSe/ZnS quantum dot (SSB/L-QD) complexes. It was worth mentioning that the signal tracer (SSB/L-QD) with vesicle shape, which was fabricated being encapsulated with a number of quantum dots and SSB. The nanotracer has excellent signal amplification effects. The vesicle composite probe was formed by combining aptamer labeled nano-gold (Au-Apt) and SSB/L-QD. Which based on SSB's specific affinity towards aptamer. This probe can't emit fluoresce which is in "off" state because the signal from SSB/L-QD as donor can be quenched by the Au-aptas acceptor. When CAP was added in the composite probe solution, the aptamer on the Au-Apt can be preferentially bounded with CAP then release from the composite probe, which can turn the "off" signal of SSB/L-QD tracer into "on" state. The assay indicates excellent linear response to CAP from 0.001 nM to 10 nM and detection limit down to 0.3 pM. The vesicle probes with size of 88 nm have strong signal amplification. Because a larger number of QDs can be labeled inside the double phosphorus lipid membrane. Besides, it was employed to detect CAP residues in the milk samples with results being agreed well with those from ELISA, verifying its accuracy and reliability. PMID:27251948

  10. A human parvovirus, adeno-associated virus, as a eucaryotic vector: Transient expression and encapsidation of the procaryotic gene for chloramphenicol acetyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Tratschin, J.D.; West, M.H.P.; Sandbank, T.; Carter, B.J.

    1984-10-01

    The authors have used the defective human parvovirus adeno-associated virus (AAV) as a novel eurocaryotic vector (parvector) for the expression of a foreign gene in human cells. The recombinant, pAV2, contains the AAV genome in a pBR322-derived bacterial plasmid. When pAV2 is transfected into human cells together with helper adenovirus particles, the AAV genome is rescued from the recombinant plasmid and replicated to produce infectious AAV particles at high efficiency. To create a vector, we inserted a procaryotic sequence coding for chloramphenicol acetyltransferase (CAT) into derivatives of pAV2 following either of the AAV promoters p/sub 40/ (pAVHiCAT) and p/sub 19/ (pAVBcCAT). When transfected into human 293 cells or HeLa cells, pAVHiCAT expressed CAT activity in the absence of adenovirus. In the presence of adenovirus, this vector produced increased amounts of CAT activity and the recombinant AAV-CAT genome was replicated. In 293 cells, pAVBcCAT expressed a similar amount of CAT activity in the absence or presence of adenovirus and the recombinant AAV-CAT genome was not replicated. In HeLa cells, pAVBcCAT expressed low levels of CAT activity, but this level was elevated by coinfection with adenovirus particles or by cotransfection with a plasmid which expressed the adenovirus early region 1A (E1A) product. The E1A product is a transcriptional activator and is expressed in 293 cells. Thus, expression from two AAV promoters is differentially regulated: expression from p/sub 19/ is increased by E1A, whereas p/sub 40/ yields high levels of constitutive expression in the absence of E1A. Both AAV vectors were packaged into AAV particles by complementation with wild-type AAV and yielded CAT activity when subsequently infected into cells in the presence of adenovirus.

  11. 氯霉素水杨酸搽剂微生物限度检查方法的验证%Verification of the Method to Determine the Microbial Limit Test for Chloramphenicol Salicylic Acid Liniment

    Institute of Scientific and Technical Information of China (English)

    邓菲; 宋莹

    2014-01-01

    Objective To establish a method to determine the microbial limit test for Chloramphenicol salicylic acid liniment. Method According to China Pharmcopoeia edition 2010,the antimicrobial effect of Chloramphenicol salicylic acid liniment was determined by recovery rate with 5 control trains.Result Antibacterial effect was not found against escherichia coli,bacillus subtilis,staphylococcus aureus,Candida albicans and Aspergillus niger.Conventional method was used for counting bacteria. Conclusion The method is sample and it can be used for qualitity control of Chloramphenicol salicylic acid liniment.%目的:建立氯霉素水杨酸搽剂的微生物限度检查方法。方法参照《中国药典》2010版,采用5种阳性对照菌回收率试验测定其是否含抑菌成分。结果该品种对大肠埃希菌、枯草芽孢杆菌、金黄色葡萄球菌、白色念珠菌和黑曲霉均没有抑菌活性,细菌、霉菌和酵母菌数及控制菌的检查采用常规法进行。结论用该方法进行微生物限度检查可以客观地反映药物中微生物的污染状况,可用于该制剂微生物控制。

  12. Role of the two component signal transduction system CpxAR in conferring cefepime and chloramphenicol resistance in Klebsiella pneumoniae NTUH-K2044.

    Directory of Open Access Journals (Sweden)

    Vijaya Bharathi Srinivasan

    Full Text Available BACKGROUND: Klebsiella pneumoniae is a gram-negative, non-motile, facultative anaerobe belonging to the Enterobacteriaceae family of the γ-Proteobacteria class in the phylum Proteobacteria. Multidrug resistant K. pneumoniae have caused major therapeutic problems worldwide due to emergence of extended-spectrum β-lactamase producing strains. Two-component systems serve as a basic stimulus-response coupling mechanism to allow organisms to sense and respond to changes in many different environmental conditions including antibiotic stress. PRINCIPAL FINDINGS: In the present study, we investigated the role of an uncharacterized cpxAR operon in bacterial physiology and antimicrobial resistance by generating isogenic mutant (ΔcpxAR deficient in the CpxA/CpxR component derived from the hyper mucoidal K1 strain K. pneumoniae NTUH-K2044. The behaviour of ΔcpxAR was determined under hostile conditions, reproducing stresses encountered in the gastrointestinal environment and deletion resulted in higher sensitivity to bile, osmotic and acid stresses. The ΔcpxAR was more susceptible to β-lactams and chloramphenicol than the wild-type strain, and complementation restored the altered phenotypes. The relative change in expression of acrB, acrD, eefB efflux genes were decreased in cpxAR mutant as evidenced by qRT-PCR. Comparison of outer membrane protein profiles indicated a conspicuous difference in the knock out background. Gel shift assays demonstrated direct binding of CpxR(KP to promoter region of ompC(KP in a concentration dependent manner. CONCLUSIONS AND SIGNIFICANCE: The Cpx envelope stress response system is known to be activated by alterations in pH, membrane composition and misfolded proteins, and this systematic investigation reveals its direct involvement in conferring antimicrobial resistance against clinically significant antibiotics for the very first time. Overall results displayed in this report reflect the pleiotropic role of the Cpx

  13. 甲基丙烯酸羟乙酯与丙稀酰胺共聚特水凝胶的合成及氯霉素缓释性能研究%Study on Synthesis and chloramphenicol Release of poly (2-hydroxyethylmethacrylate-co-acrylamide) hydrogels

    Institute of Scientific and Technical Information of China (English)

    黎新明; 崔英德

    2008-01-01

    In this article,poly(2-hydroxyethylmethacrylate-co-acrylamide)hydrogels were synthesized by bulk free-radical copolymerization of 2-hydroxyethylmethacrylate(HEMA)and acrylamide(AAm)for soft contact lens(SCL)-based ophthalmic drug delivery system.The copolymer was characterized with FT-IR and SEM,the swelling property of the hydrogels were studied by gravimetrical method.and chloramphenicol was used as a model drug to investigate drug release profile of the hydrogels.The results showed that poly(2-hydroxyethylmethacrylateco-acrylamide)hydrogels were transparent and useful SCL biomaterial.the water content increased as AAm content increase and pH decrease,and in the sanqe way,hydrogel composition affected chloramphenicol release process too.Migration rate of chloramphenicol increased as the AAm content in the hydrogels increased in the first stage of diffusion process,whereas there Was no significant difference thereafter.

  14. Effects of Chopping on Chloramphenicol Residues and Quality of Freshwater Fish%斩拌对淡水鱼肉品质及氯霉素残留的影响

    Institute of Scientific and Technical Information of China (English)

    梁丽雅; 王綪; 王婧; 杨毅青; 马俪珍; 闫师杰

    2014-01-01

    以鲢鱼、鲤鱼和鲶鱼肉为试材,研究斩拌工序对鱼肉品质及氯霉素残留量的影响。结果表明:经斩拌后,鱼肉中蛋白质含量呈下降趋势,鲤鱼显著低于鲢鱼和鲶鱼;自由水峰面积减少,不易流动水峰面积增加,不同斩拌处理的鱼肉水分分布差异不显著;脂肪含量差异不显著;HL斩拌的鱼肉灰分和蛋白质损失量最小。斩拌对鱼肉L*和a*值影响较小,使pH不同程度地升高(6.5~7.5);HL斩拌可显著降低TBARS值。经斩拌氯霉素残留降解率达73.33%~99.13%。斩拌可有效去除氯霉素残留,经HL斩拌后的鱼肉品质最佳。%With silver carp, carp, and catfish flesh as the experimental material,effects of chopping processing on the quality and chloramphenicol residues of freshwater fish were studied. The results showed that after chopped, that protein content of fish flesh showed a downward trend, the value of carp flesh was significantly lower than that of chub and catfish;Free-water content decreased, immobilized-water content increased, and water distribution of different chopping was not significant. The difference of fat content between them was not significant;the ash and protein yield loss in fish flesh was least by HL chopping. The chopping had less affection on L*and a*value of fish flesh. The pH of fish flesh increased in different degrees (6.5-7.5);TBARS values of chub and carp decreased significantly, but the catfish raised by HL chopping. Degradation rate of chloramphenicol residues was 77.33%-99.13%. Chopping can effectively get rid of the chloramphenicol residue , and the quality of fish flesh was the best by HL chopping.

  15. Status Analysis and Discuss of metronidazole & chloramphenicol illegally adulteration in commercial cosmetics for removing acne%市售祛痘类化妆品中非法添加甲硝唑、氯霉素的现状分析和探讨

    Institute of Scientific and Technical Information of China (English)

    朱燕; 严晓明; 蓝献泉

    2016-01-01

    目的:对韶关市售祛痘化妆品非法添加甲硝唑、氯霉素的现状进行分析和探讨。方法在已建立的化妆品中非法添加甲硝唑、氯霉素筛查方法的基础上,对韶关市零售店、药店、商场、超市、化妆品专卖店5种类型的销售场所所售祛痘类28个厂家32批化妆品进行了测定,涉及面膜、护肤膏霜、乳液、洗面系列。结果检出非法添加甲硝唑、氯霉素0批次。结论所涉销售场所祛痘类化妆品中非法添加甲硝唑、氯霉素现象相对乐观,通过本文分析,为该问题的有效监管提供进一步思路。%Objective to analysis and discuss of metronidazole& chloramphenicol Illegally adulteration in commercial cosmetics for removing acneMethods Metronidazole&chloramphenicol in the cosmetics for removing acne gotten in retail store drugstore,market,store,cosmetics shop was determined by the developed method.Results A total of 32 batches samples from 28 manufacturing enterprises were analyzed.involving facial mask,skin care creams,lotions,Cleansing Foam. And illegally adulteration metronidazole& chloramphenicol was 0,the positive rate was 0%.Conclusion The situation of Metronidazole& chloramphenicol adulteration in acne cosmetics was relatively optimistic, this analyzes provide ideas for effective regulation of metronidazole;chloramphenicol adulteration.

  16. 微波辅助合成分子印迹聚合物用于萃取蜂蜜中的氯霉素%Preparation of Molecularly Imprinted Polymers by Microwave-assisted Polymerization for the Extraction of Chloramphenicol from Honey†

    Institute of Scientific and Technical Information of China (English)

    陈海燕; 丁兰; 刘密兰

    2015-01-01

    The chloramphenicol imprinted polymers were prepared by means of microwave­assisted polymeri­ zation and applied for the separation and enrichment of chloramphenicol from honey. The polymers were ap­ plied as solid­phase extraction materials to extract and clean up the chloramphenicol in honey, followed by the liquid chromatography­tandem mass spectrometry ( LC­MS/MS ) analysis. The morphology of polymers was characterized by scanning electron microscope( SEM) . The binding property and selectivity of polymers were evaluated and the Scatchard analysis was carried out. The polymers appeared to be spherical in shape and had a good selectivity. The apparent maximum binding amount of the polymers was 427. 7 μmol/g. The detection limit of chloramphenicol was 0. 13 ng/g. The linearity range and correlation coefficient of the method were 0. 5—100 ng/g and 0. 999, respectively. The recoveries of six spiked honey samples were in the range of 88%—93%. The proposed method has been successfully applied for the detection of chloramphenicol from honey.%采用微波辅助法快速制备以氯霉素为模板分子的分子印迹聚合物.将合成的聚合物作为吸附剂,选择性分离和富集蜂蜜样品中的氯霉素,并结合高效液相色谱­串联质谱法对萃取物进行分析.对合成的分子印迹聚合物进行了表征,考察了聚合物的吸附性能及其选择性,并进行了Scatchard分析.结果表明,合成的聚合物为球形,对氯霉素具有良好的识别能力,最大表观结合量可达0.428 mmol/g.该方法的线性范围为0.5~100 ng/g,相关系数>0.999,蜂蜜中氯霉素的检出限为0.13 ng/g,6种蜂蜜样品中氯霉素的加标回收率范围为88%~93%.

  17. A novel "dual-potential" electrochemiluminescence aptasensor array using CdS quantum dots and luminol-gold nanoparticles as labels for simultaneous detection of malachite green and chloramphenicol.

    Science.gov (United States)

    Feng, Xiaobin; Gan, Ning; Zhang, Huairong; Yan, Qing; Li, Tianhua; Cao, Yuting; Hu, Futao; Yu, Hongwei; Jiang, Qianli

    2015-12-15

    A novel type of "dual-potential" electrochemiluminescence (ECL) aptasensor array was fabricated on a homemade screen-printed carbon electrode (SPCE) for simultaneous detection of malachite green (MG) and chloramphenicol (CAP) in one single assay. The SPCE substrate consisted of a common Ag/AgCl reference electrode, carbon counter electrode and two carbon working electrodes (WE1 and WE2). In the system, CdS quantum dots (QDs) were modified on WE1 as cathode ECL emitters and luminol-gold nanoparticles (L-Au NPs) were modified on WE2 as anode ECL emitters. Then the MG aptamer complementary strand (MG cDNA) and CAP aptamer complementary strand (CAP cDNA) were attached on CdS QDs and L-Au NPs, respectively. The cDNA would hybridize with corresponding aptamer that was respectively tagged with cyanine dye (Cy5) (as quenchers of CdS QDs) and chlorogenic acid (CA) (as quenchers of l-Au NPs) using poly(ethylenimine) (PEI) as a bridging agent. PEI could lead to a large number of quenchers on the aptamer, which increased the quenching efficiency. Upon MG and CAP adding, the targets could induce strand release due to the highly affinity of analytes toward aptamers. Meanwhile, it could release the Cy5 and CA, which recovered cathode ECL of CdS QDs and anode ECL of L-Au NPs simultaneously. This "dual-potential" ECL strategy could be used to detect MG and CAP with the linear ranges of 0.1-100 nM and 0.2-150 nM, with detection limits of 0.03 nM and 0.07 nM (at 3sB), respectively. More importantly, this designed method was successfully applied to determine MG and CAP in real fish samples and held great potential in the food analysis. PMID:26190470

  18. Molecular dynamics simulations on the pre-organization system of chloramphenicol molecularly imprinted polymer%氯霉素分子印迹聚合物预组装过程的分子动力学研究

    Institute of Scientific and Technical Information of China (English)

    熊明洲; 李雁; 李璐; 解新安; 郑璐丝

    2012-01-01

    以氯霉素(CAP)为模板分子,甲基丙烯酸(MAA)、丙烯酸(AA)、丙烯酰胺(AM)、甲基丙烯酸甲酯(MMA)为功能单体,采用分子动力学方法研究了不同预组装体系中CAP与功能单体的相互作用,考察了溶剂(氯仿、甲醇、乙腈)对预组装体系的影响,并采用试验方法验证模拟结果,最后研究了预组装体系中CAP与功能单体相互作用距离.结果表明:模拟结果与实验结果一致,在甲醇溶剂中,CAP与功能单体相互作用强弱顺序为MAA>AA>AM>MMA;乙腈溶剂中顺序为AM>MAA> AA>MMA.CAP与功能单体相互作用基团的距离在1.8~5.0(A),两者间可能存在较强的非共价结合作用.%An molecular dynamics simulations study was made on molecularly imprinted polymers (MIPs) using chloramphenicol as template, methacrylic acid (MAA), acrylicacid (AA), acrylamide (AM), methyl methacrylate (MMA) as functional monomers respectively. The investigation was carried out for the pre-organization system in order to predict the interaction energies and the effect of solvent (chloroform, methanol, acetonitrile) on the pre-organization system. The corresponding experimental results were used to verify the simulation results. Finally, the binding distance between CAP and monomers was studied. The conclusion shows that the simulation results were consistent with experimental results. The order of interaction energy is MAA>AA>AM>MMA in methano! while AM>MAA> AA>MMA in acetonitrile. The distance of closest approach between CAP and monomers is between (1.8~5.0) A, it appears that there may be strong no-colvent interaction between CAP and monomers.

  19. The Clinical Efficacy of Blue Red Led Phototherapy Combined with Jinhua Xiaocuo Pills and Chloramphenicol Tincture on the Treatment of Acne Vulgaris%红蓝光治疗仪联合金花消痤丸及氯霉素酊治疗寻常痤疮疗效观察

    Institute of Scientific and Technical Information of China (English)

    张玉红

    2013-01-01

    Objective To observe the clinical efficacy of blue and red led phototherapy combined with jinhua xiaocuo pills and chloramphenicol tincture on the treatment of patients with acne vulgaris. Methods Patients were randomly divided into two groups,60 patients of treatment group were treated by red blue phototherapy combined with jinhua xiaocuo pills and chloramphenicol tincture, 60 patients of control group were treated with jinhua xiaocuo pills and chloramphenicol tincture. Acne was assessed at baseline and 4 weeks later. Results The effective rate in treating group was 91.67% and control group was 65.00% (P <0. 05) ;Two subjects reported side effects of the light treatment in the form of mild facial erythema, itching and scaling. Conclusion Blue and red led phototherapy combined with jinhua xiaocuo pills and chlorampenicol tincture on the treatment of acne is superior to jinhua xiaocuo pills and chlorampenicol tincture.%目的 观察红蓝光治疗仪联合金花消痤丸及氯霉素酊治疗寻常痤疮的临床疗效.方法 将入选患者随机分成两组,治疗组60例用红蓝光照射联合口服金花消痤丸剂外用氯霉素酊治疗,对照组60例仅口服金花消痤丸剂外用氯霉素酊治疗,方法同治疗组,疗程均为4周.结果 治疗结束后,治疗组有效率91.67%,对照组65.00%,差异有统计学意义(P<0.05);治疗组有2例经红蓝光照射后面部皮肤出现轻度潮红、瘙瘁和脱屑.结论 红蓝光治疗仪联合口服金花消痤丸及外用氯霉素酊治疗痤疮起效快、有效率高、复发率低、值得临床选用.

  20. Determinação de resíduos de cloranfenicol em amostras de leite e mel industrializados utilizando a técnica de espectrometria de massas em "tandem" (CLAE-EM/EM Determination of chloramphenicol residues in industrialized milk and honey samples using LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Helio Alves Martins Júnior

    2006-06-01

    Full Text Available The present work shows a method for the determination of chloramphenicol (CAP antibiotic in milk, powder milk and honey. The solid phase extraction and liquid-liquid extraction were applied as a clean-up and pre-concentration strategies followed by LC-ESI/MS/MS analysis. The recovery was studied for different fortification levels from 0.05 to 1.00 µg L-1 in milk, showing values between 91 101% and RSD bellow 8.0%, while honey was spiked with a concentration of 0.20 µg kg-1 yelding a mean recovery of 83% and RSD of 6.5%. The quantification transition 321>152 showed a LOD of 0.52 ng kg-1 and LOQ of 1.85 ng kg-1.

  1. 杜氏盐藻甘油醛-3-磷酸脱氢酶基因启动子驱动氯霉素乙酰转移酶基因的表达及其活性检测%Expression and activity detection of chloramphenicol acetyltransferase gene driven by the glyceraldehyde-3-phosphate dehydrogenase gene of Dunaliella salina

    Institute of Scientific and Technical Information of China (English)

    张小毅; 刘巨源; 邱乐乐; 贾岩龙

    2012-01-01

    目的 为建立稳定高效的盐藻生物反应器寻找合适的内源性启动子驱动表达外源基因.方法 克隆鉴定了盐藻甘油醛-3-磷酸脱氢酶(GAPDH)基因5 ′上游区序列并成功构建由盐藻GAPDH基因启动子驱动的氯霉素乙酰转移酶(CAT)基因表达载体pUC-Gcat.利用构建的表达载体电击转化盐藻并在含有氯霉素的培养基中筛选转化藻株.随机挑选稳定转化的盐藻藻株进行CAT酶联免疫吸附测定分析.结果 获得3株稳定转化的盐藻藻株.聚合酶链式反应鉴定和CAT酶联免疫吸附测定分析结果表明,CAT基因已整合到了转化的盐藻基因组中.结论 本研究所克隆的内源性盐藻GAPDH基因启动子能够驱动CAT基因在盐藻中表达.%Objective To explore expression of foreign gene driven by a strong endogenous promoter in order to construct stable and high-performance bioreactors in Dunaliella salina. Methods In the present study, the upstream sequence of glyceraldehyde phosphate dehydrogenase of Dunaliella salina was cloned and identificated. Using electroporation, the alga was transformed with a plasmid pUC-Ccat containing giyceraldehyde-3-phosphate dehydrogenase ( GAPDH) gene promoter of Du-naliella salina and chloramphenicol acetyltransferase ( CAT) gene as a seletable gene. Using the expression vector, the Dunaliella salina cell was translated and the transformational strain was screened in nutrient medium containing chloramphenicol. The stable transformational strain was selected randomly to undertake CAT enzyme linked immunosorbent assay (ELISA). Results Three stable transformational strain were obtained. The results of polymerase chain reaction and CAT ELISA indicated that the CAT gene had been transferred to the alga. Conclusion The results of this paper suggest that the GAPDH gene promoter can work for genetic transformation of Dunaliella salina.

  2. 77 FR 41412 - Determination That CHLOROMYCETIN (Chloramphenicol) Capsules, 250 Milligrams, Were Withdrawn From...

    Science.gov (United States)

    2012-07-13

    ..., 250 Milligrams, Were Withdrawn From Sale for Reasons of Safety or Effectiveness AGENCY: Food and Drug... determines that the listed drug was withdrawn from sale for reasons of safety or effectiveness (21 CFR 314..., whether a listed drug was withdrawn from sale for reasons of safety or effectiveness. This...

  3. Engineered defective interfering RNAs of Sindbis virus express bacterial chloramphenicol acetyltransferase in avian cells.

    OpenAIRE

    Levis, R; Huang, H.; Schlesinger, S

    1987-01-01

    We are investigating the feasibility of using the positive-strand RNA virus Sindbis virus and its defective interfering (DI) particles as vectors for introducing foreign genes into cells. In previous work we showed by deletion mapping of a cloned cDNA derived from one of the DI RNAs that only nucleotides at the 3' and 5' termini of the RNA are essential for the DI RNA to be amplified after it is transfected into cells in the presence of helper virus. As a first step in developing a vector we ...

  4. Multi-antibiotic resistant brain abscess sensitive only to chloramphenicol: a case report

    OpenAIRE

    Rehman, Atiq Ur; Rehman, Tausif; Ali, Rushna

    2009-01-01

    Introduction A brain abscess is a focal, intracerebral infection that begins as a localized area of cerebritis and develops into a collection of pus surrounded by a well-vascularized capsule. Case presentation An 18 year old male was diagnosed to have culture-negative bilateral subdural empyema, which was drained and the patient was discharged, only to return 3 months later with a left temporo-parietal abscess that was drained and continued to show no growth on cultures and was non-responsive...

  5. Chloramphenicol encapsulated in poly-ε-caprolactone–pluronic composite: nanoparticles for treatment of MRSA-infected burn wounds

    OpenAIRE

    Kalita S; Devi B; Kandimalla R; Sharma KK; Sharma A; Kalita K; Kataki AC; Kotoky J

    2015-01-01

    Sanjeeb Kalita,1 Banasmita Devi,1 Raghuram Kandimalla,1 Kaustav Kalyan Sharma,1 Arup Sharma,2 Kasturi Kalita,3 Amal Chandra Kataki,4 Jibon Kotoky1 1Institute of Advanced Study in Science and Technology (IASST), Division of Life Sciences, Paschim Boragaon, Garchuk, Guwahati, Assam, India; 2College of Veterinary Science, Assam Agriculture University, Khanapara, Guwahati, Assam, India; 3Hyat Hospital, Lalganesh, Guwahati, Assam, India; 4Dr B Borooah Cancer Institute, Guwahati, Assam, India Abs...

  6. Background and Objective: Listeria monocytogenes is a bacterium transferred by foods and is the agent of many sporadic and epidemic diseases in humans. This study aimed to investigate the prevalence of L. monocytogenes and to determinine their antibiotic resistance profile in red meats. Material and Methods: this cross-sectional study was performed on 400 red meat samples obtained from industrial slaughterhouses placed in Kerman, Iran. First, the samples were enriched with Simultaneous Enrichment Broth (SEB, and then plated onto Palcam agar and Tryptic Soy Broth Yeast Extract Broth (TSAYE. After identification of the isolates based on biochemical tests and PCR, the isolates were checked for their antibiotic resistance profile using disk Diffusion Results: of 400 samples, 12 samples (3% were contaminated with different species of Listeria. Using PCR, hly gene was recognized in eight samples (2% of L. monocytogenes. Furthermore, there was a significant difference in isolation rate of lamb samples compared to cow ones. While all of the isolates were resistant to clindamycin, amikacin and chloramphenicol, they were sensitive to penicillin. Conclusion: in spite of low rate of infection in red meat samples in Kerman city, due to high risk of Listeria contamination in red meats, we recommend applying a routine screening to identify this bacterium in our county.

    Directory of Open Access Journals (Sweden)

    Kargar, M. (PhD

    2014-11-01

    Full Text Available Background and Objective: Listeria monocytogenes is a bacterium transferred by foods and is the agent of many sporadic and epidemic diseases in humans. This study aimed to investigate the prevalence of L. monocytogenes and to determinine their antibiotic resistance profile in red meats. Material and Methods: this cross-sectional study was performed on 400 red meat samples obtained from industrial slaughterhouses placed in Kerman, Iran. First, the samples were enriched with Simultaneous Enrichment Broth (SEB, and then plated onto Palcam agar and Tryptic Soy Broth Yeast Extract Broth (TSAYE. After identification of the isolates based on biochemical tests and PCR, the isolates were checked for their antibiotic resistance profile using disk Diffusion Results: of 400 samples, 12 samples (3% were contaminated with different species of Listeria. Using PCR, hly gene was recognized in eight samples (2% of L. monocytogenes. Furthermore, there was a significant difference in isolation rate of lamb samples compared to cow ones. While all of the isolates were resistant to clindamycin, amikacin and chloramphenicol, they were sensitive to penicillin. Conclusion: in spite of low rate of infection in red meat samples in Kerman city, due to high risk of Listeria contamination in red meats, we recommend applying a routine screening to identify this bacterium in our county

  7. Promoter region of interleukin-2 gene undergoes chromatin structure changes and confers inducibility on chloramphenicol acetyltransferase gene during activation of T cells.

    OpenAIRE

    Siebenlist, U; Durand, D B; Bressler, P; Holbrook, N J; Norris, C A; Kamoun, M.; Kant, J A; Crabtree, G R

    1986-01-01

    The chromatin structure of the interleukin-2 (IL-2) gene was probed by DNase I treatment of isolated nuclei. The 5' region of the IL-2 gene contains three regions of hypersensitivity to DNase I. When peripheral blood T cells or Jurkat T cells are stimulated with mitogens, IL-2 message is induced, and the promoter region of the IL-2 gene develops an additional hypersensitive site. This suggests that a DNA sequence close to the transcriptional start site is involved in the transduction of the e...

  8. Drug: D00104 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D00104 Drug Chloramphenicol (JP16/USP/INN); CP; Amphicol (TN); Chloromycetin (TN); Econochlor (T ... col D00104 Chloramphenicol (JP16/USP/INN) D10 ANTI-ACNE ... PREPARATIONS D10A ANTI-ACNE ... PREPARATIONS FOR TOPIC ... AL USE D10AF Antiinfectives for treatment of acne ... D10AF03 Chloramphenicol D00104 Chloramphenicol (JP ...

  9. Drug: D07675 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D07675 Drug Chloramphenicol succinate; Chloramphenicol ICN (TN) C15H16Cl2N2O8 422.0284 423.2021 ... phenicol D07675 Chloramphenicol succinate D10 ANTI-ACNE ... PREPARATIONS D10A ANTI-ACNE ... PREPARATIONS FOR TOPIC ... AL USE D10AF Antiinfectives for treatment of acne ... D10AF03 Chloramphenicol D07675 Chloramphenicol suc ...

  10. 圈养虎源大肠杆菌中氯霉素类药物耐药基因的调查%Investigation of Chloramphenicol Drugs Resistant Gene in E.coli Isolated from Captive Tigers

    Institute of Scientific and Technical Information of China (English)

    薛原; 王晓菲; 陈建飞

    2016-01-01

    采用K-B法检测30株虎源大肠杆菌对氯霉素类药物的耐药性.根据耐药表型和耐药基因的流行情况,指导临床合理用药.结果表明:30株虎源大肠杆菌对氯霉素的耐药率为85%,对氟苯尼考的耐药率为78%.cmlA基因的阳性率为70%,floR基因的阳性率为23.3%.

  11. First step toward a virus-derived vector for gene cloning and expression in spiroplasmas, organisms which read UGA as a tryptophan codon: synthesis of chloramphenicol acetyltransferase in Spiroplasma citri.

    OpenAIRE

    Stamburski, C; Renaudin, J; Bove, J M

    1991-01-01

    Spiroplasmas are wall-less procaryotes in which the UGA codon serves not as a stop signal but as a code for the amino acid tryptophan. Spiroplasma genes that contain UGA codons thus cannot be studied in the usual Escherichia coli cloning and expression systems. Although this problem can be circumvented by using UGA-suppressor strains of E. coli, spiroplasmas themselves would provide a more efficient cloning and expression host. We have now successfully employed the replicative form (RF) of a ...

  12. Drug: D04106 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D04106 Mixture, Drug Chloramphenicol - colistin sodium methanesulfonate mixt; Colim...3 Agents affecting sensory organs 131 Ophthalmic agents 1319 Others D04106 Chloramphenicol - colistin sodium methanesulfonate mixt PubChem: 17398026 ...

  13. Drug: D07674 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D07674 Drug Chloramphenicol stearate; Quemicetina (TN) C29H46Cl2N2O6 588.2733 589.5913 D07674.gi ... mphenicol D07674 Chloramphenicol stearate D10 ANTI-ACNE ... PREPARATIONS D10A ANTI-ACNE ... PREPARATIONS FOR TOPIC ... AL USE D10AF Antiinfectives for treatment of acne ... D10AF03 Chloramphenicol D07674 Chloramphenicol ste ...

  14. Drug: D01072 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D01072 Drug Chloramphenicol palmitate (JP16/USP); Chloromycetin palmitate (TN) C27H42Cl2N2O6 560 ... 1072 Chloramphenicol palmitate (JP16/USP) D10 ANTI-ACNE ... PREPARATIONS D10A ANTI-ACNE ... PREPARATIONS FOR TOPIC ... AL USE D10AF Antiinfectives for treatment of acne ... D10AF03 Chloramphenicol D01072 Chloramphenicol pal ...

  15. Drug: D02185 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D02185 Drug Chloramphenicol sodium succinate (JP16/USP); CP; Chloromycetin succinate (TN) C15H15 ... loramphenicol sodium succinate (JP16/USP) D10 ANTI-ACNE ... PREPARATIONS D10A ANTI-ACNE ... PREPARATIONS FOR TOPIC ... AL USE D10AF Antiinfectives for treatment of acne ... D10AF03 Chloramphenicol D02185 Chloramphenicol sod ...

  16. Survival and behavior of silver catfish, Rhamdia quelen, submitted to antibiotics and sodium chloride treatments

    OpenAIRE

    Andrade Luciana Segura de; Andrade Rafael Luiz Barboza de; Becker Alexssandro Geferson; Baldisserotto Bernardo

    2006-01-01

    In order to evaluate the use of antibiotics and NaCl on the behavior and survival of silver catfish, Rhamdia quelen, infested by Ichthyophthirius multifiliis and infected with Aeromonas hydrophila, juveniles were treated with chloramphenicol, chloramphenicol + salt, oxytetracycline, oxytetracycline + salt and water alone (control). Fish survival in the treatments with chloramphenicol + salt and oxytetracycline + salt was significantly higher than in the other treatments. The treatment with ch...

  17. Separation and determination of chloramphenicol in sewage using a small molecules-salt aqueous two-phase flotation system coupled with HPLC%小分子双水相浮选高效液相色谱法测定污水中痕量氯霉素

    Institute of Scientific and Technical Information of China (English)

    姚以亮; 关卫省

    2011-01-01

    用乙醇/磷酸氢二钾双水相体系浮选污水中的氯霉索,通过对盐的质量分数、有机溶剂的体积、气体流速和浮选时间的选择和优化,在理想条件下,氯霉素的平均浮选效率可以达到94%.该方法用于河水和鱼塘水样品中氯霉素的检测,检出限为0.5 ng/mL,加标回收率为89.44%~100.16%,相对标准偏差RSD为1.1%~2.1%,适用于污水中痕量氯霉素的分离/富集及分析测定.%C2H5OH/K2HPO4 two-phase aqueous system was used to floate CAP in sewage. By selecting and optimizing mass percentage of salt, volume of organic solvent, gas flow rate and flotation time, under the optimum conditions,the average floatation efficiency was up to 94% . The method used to detect CAP in the samples of river and pond water, the detection limit was 0. 5 ng/mL, the relative recovery was 89. 44% ~ 100. 16% with relative standard deviation RSD = 1. 1%~ 2. 1% . The method is applicable to analyze the trace CAP in swage.

  18. 用于氯霉素、克伦特罗和雌二醇三种兽药残留检测的高通量悬浮芯片技术研究%Development of a high-throughput suspension microarray technology for detection of three kinds of veterinary drug residues: chloramphenicol, clenbuterol and 17-beta-estradiol

    Institute of Scientific and Technical Information of China (English)

    刘楠; 苏璞; 高志贤; 朱茂祥; 杨陟华; 潘秀颉; 晁福寰

    2009-01-01

    Objective To establish a novel suspension microarray technology for the detection of three kinds of veterinary drug residues: ehloramphenicol, clenbuterol and 17-beta-estradiol (CAP, CL and E2). Methods The three conjugates that veterinary drug coupled with bovine serum albumin(BSA) were synthesized and identified by ultraviolet (UV)spectrophotometry and mass spectrum. The veterinary drug conjugates were immobilized on the polystyrene fluorescent micrespheres/beads. There were competitive reactions between the veterinary drugs in the aqueous phase and that on the beads for combination with their specific biotinylated monoclonal antibodies. The optimum amount of the veterinary drug conjugates and the antibodies were optimized and selected. The detective standard curves were plotted. The specificity and the unknown samples were also determined by grouping according to different concentrations of the interferers and the samples. Meantime, the different microstructures of the surfaces of the beads were also observed by scanning electron microscope. Results Couplings were completed between small molecular veterinary drugs and BSA. The amounts of the three conjugates and the antibodies were optimized. The detective standard curves of the suspension array and their corresponding coefficients of determination (R2) were good (R2> 0.99) .The detection ranges of the three veterinary drugs were (40.00 -6.25) x 105 ng/L, (50.00 -7.81 )×105 ng/L and 1.00×103-7. 29×105 ng/L respectively. Simultaneously, the specific detection of the suspension microarray was excellent and did not indicate significant cross-reactions. Errors between the found and the real are in the range of 8.09%-17.03%. It can be considerd that the relative standard deviations were relatively small. Successful couplings were also directly confirmed by the observation for microstructures of the surfaces of the beads by scanning of electron microscope and laid good foundation for the following responses. Conclusion The high-throughput suspension microarray should provide a novel method for multi-analysis of the veterinary drugs and have a wide applicative prospects with simple operation, sensitive, rapid and low cost.%目的 建立一种氯霉素、克伦特罗和雌二醇(17-beta-estradiol,E2)的3种兽药残留的新型高通量悬浮芯片检测技术.方法 合成3种兽药的牛血清白蛋白(bovine serum albumin,BSA)结合物,并进行紫外和质谱鉴定.将3种蛋白结合物偶联于聚苯乙烯荧光微球上,在液相反应体系中3种小分子兽药抗原和微球上的结合物共同竞争液相中各自特异性的生物素化单抗,优化和筛选出微球上偶联BSA结合物和反应抗体的最适加入量.绘制出3种兽药残留检测的标准曲线;对不同浓度的干扰物和待测物分组,以此进行特异性检测和盲样测定.并用扫描电子显微镜(简称电镜)进行微球表面微观结构观察.结果 3种小分子兽药可与BSA成功偶联;3种结合物的加入量和抗体的加入量分别做了优化;悬浮芯片检测的标准曲线方程和方程相应的决定系数(R2)表现良好,R2>0.99;3种兽药悬浮芯片的检测区间分别为(40.00~6.25)×105ns/L,(50.00~7.81)×105ng/L和1.00×103~7.29×105ng/L;最低检出限为:40 ng/L、50 ng/L和1 μg/L;同时,悬浮芯片的特异度测试良好,与其他药物无明显交叉反应;对盲样测定的检测浓度值与实际浓度偏差在8.09%~17.03%,可认为偏差较小.电镜对微球表面微观结构的观察也直观地确证了蛋白在微球上的成功偶联.结论 高通量悬浮芯片技术操作简单,灵敏快速,成本低廉,为多种兽药残留的快速检测提供了新方法,具有广阔的应用和发展前景.

  19. Gene : CBRC-AGAM-07-0016 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-AGAM-07-0016 U C UNKNOWN MDTL_VIBPA 2e-11 32% ref|YP_855389.1| chloramphenicol resistance p ... rotein [Aeromonas ... hydrophila subsp. hydrophila ATCC 7966] gb|ABK3699 ... 6.1| chloramphenicol resistance protein [Aeromonas ... hydrophila subsp. hydrophila ATCC 7966] 1e-111 99% ...

  20. NCBI nr-aa BLAST: CBRC-ETEL-01-1461 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-ETEL-01-1461 ref|NP_691389.1| chloramphenicol resistance protein [Oceanobacill...us iheyensis HTE831] dbj|BAC12424.1| chloramphenicol resistance protein [Oceanobacillus iheyensis HTE831] NP_691389.1 0.21 28% ...

  1. NCBI nr-aa BLAST: CBRC-CREM-01-1332 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CREM-01-1332 ref|YP_001249601.1| chloramphenicol resistance protein [Legionella... pneumophila str. Corby] gb|ABQ54255.1| chloramphenicol resistance protein [Legionella pneumophila str. Corby] YP_001249601.1 4e-30 35% ...

  2. Survival and behavior of silver catfish, Rhamdia quelen, submitted to antibiotics and sodium chloride treatments

    Directory of Open Access Journals (Sweden)

    Andrade Luciana Segura de

    2006-01-01

    Full Text Available In order to evaluate the use of antibiotics and NaCl on the behavior and survival of silver catfish, Rhamdia quelen, infested by Ichthyophthirius multifiliis and infected with Aeromonas hydrophila, juveniles were treated with chloramphenicol, chloramphenicol + salt, oxytetracycline, oxytetracycline + salt and water alone (control. Fish survival in the treatments with chloramphenicol + salt and oxytetracycline + salt was significantly higher than in the other treatments. The treatment with chloramphenicol presented higher survival than the treatment with oxytetracycline and both showed significantly higher survival than control. Swimming activity was higher in the fish treated with antibiotics and salt compared to control fish. A combination of the studied antibiotics plus salt is more effective to treat both A. hydrophila infection and I. multifiliis infestation in silver catfish, but since the use of chloramphenicol is not allowed in Brazil, oxytetracycline plus salt seems to be the best treatment option.

  3. Isolation and characterization of the grain mold fungi, Cochliobolus and Alternaria spp., from sorghum using semi-selective media and DNA sequence analyses

    Science.gov (United States)

    Mold diseases, caused by fungal complexes including Alternaria, Cochliobolus and Fusarium species, limit sorghum grain production. Media were tested by plating Fusarium thapsinum, Alternaria sp. and Curvularia lunata, individually and competitively. Dichloran chloramphenicol rose bengal (DRBC) and m...

  4. Mechanisms of antimicrobial resistance and genetic relatedness among enterococci isolated from dogs and cats in the United States

    Science.gov (United States)

    Aims: In this study, mechanisms of antimicrobial resistance and genetic relatedness among resistant enterococci from dogs and cats in the United States were determined. Methods and Results: Enterococci resistant to chloramphenicol, ciprofloxacin, erythromycin, gentamicin, kanamycin, streptomycin,...

  5. Interactions of bacteria with diatoms: Influence on natural marine biofilms.

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; DeCosta, P.M.; Anil, A.C.; Sawant, S.S.

    . It was also observed that elevated nutrient concentrations overrode the inhibitory effect of chloramphenicol. Maximum Vibrio enhancement was observed in the enriched conditions during the pre-monsoon and unenriched conditions during the monsoon (with naturally...

  6. Molecular Characterization of Intrinsic and Acquired antibiotic resistance in lactic Acid bacteria and Bifidobacteria

    NARCIS (Netherlands)

    Ammor, M.S.; Flórez, A.B.; Hoek, van A.H.A.M.; Reyes-Gavilan, de los C.G.; Aarts, H.J.M.; Margolles, A.; Mayo, B.

    2008-01-01

    The minimum inhibitory concentrations (MICs) of 6 different antibiotics (chloramphenicol, clindamycin, erythromycin, streptomycin, tetracycline and vancomycin) were determined for 143 strains of lactic acid bacteria and bifidobacteria using the Etest. Different MICs were found for different species

  7. Ten years of antimicrobial susceptibility testing of Salmonella from Danish pig farms

    DEFF Research Database (Denmark)

    Emborg, Hanne-Dorthe; Baggesen, Dorte Lau; Aarestrup, Frank Møller

    2008-01-01

    the following antimicrobials were determined: ampicillin, chloramphenicol, gentamicin, nalidixic acid, colistin, streptomycin, sulphonamide, tetracycline and trimethoprim. Results: No significant development of resistance occurred within the most important serovars, except Salmonella Typhimurium. A...

  8. Cyanocobalamin Nasal Gel

    Science.gov (United States)

    ... absorbed from food; or a vegan diet (strict vegetarian diet that does not allow any animal products ... of the following: azathioprine; antibiotics such as chloramphenicol; cancer chemotherapy; colchicine; folic acid; iron supplements; medications for ...

  9. Comparative virulence genotyping and antimicrobial susceptibility profiling of environmental and clinical Salmonella enterica from Cochin, India

    Digital Repository Service at National Institute of Oceanography (India)

    Parvathi, A.; Vijayan, J.; Murali, G.; Chandran, P.

    . Newport revealed multiple drug resistance to ampicillin, amoxicillin/clavulanic acid, trimethorprim-sulfamethoxazole, chloramphenicol, tetracycline, cephalothin, and cephalexin. In comparison, S. Typhi were susceptible to all clinically relevant...

  10. Characterization of Streptococcus suis serotype 7 isolates from diseased pigs in Denmark

    DEFF Research Database (Denmark)

    Tian, Y.; Aarestrup, Frank Møller; Lu, C.P.

    2004-01-01

    erythromycin (41%), tetracycline (24%) and streptomycin (28%) was observed. Furthermore, almost all isolates (101) were resistant to sulphamethoxazol. Most isolates were susceptible to ceftiofur, chloramphenicol, florfenicol, penicillin, ciprofloxacin, trimethoprim and trimethoprim + sulphonamides. The tet...

  11. Disease: H01148 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H01148 Caulobacter infection The genus Caulobacter includes gram-negative bacteria characterized ... minoglycosides, tetracycline, chloramphenicol, and sulfadiazine . PMID:17267638 Justesen US, Holt HM, Thiesson HC, ...

  12. Penetapan Kadar Hidrokortison Asetat Dan Kloramfenikol Dalam Sediaan Krim Secara Spektrofotometri Derivatif Dengan Metode Zero Crossing

    OpenAIRE

    Syafrisal, Anjanu

    2016-01-01

    The mixture of hydrocortisone acetate and chloramphenicol is one of combination in cream supply. Determination of hydrocortisone acetate and chloramphenicol in cream can not found in any monography, either on the Indonesia Pharmacopeia 5th edition (2014) or United States Pharmacopeia (USP) 30th edition (2007) so that it required an analysis method that fulfill the test of validity in determining the mixture. The aim of this study is to test the validation of derivative spectrophotometry met...

  13. Antibacterial activity of mushroom Osmoporus odoratus

    Directory of Open Access Journals (Sweden)

    Sivakumar R

    2006-01-01

    Full Text Available The petroleum ether, chloroform, acetone and water extracts of mushroom Osmoporus odoratus were selected for examine the antibacterial activity against Staphylococcus aureus, Streptococcus pyogenes, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa by disc diffusion method using Muller Hinton agar media. And the extracts were compared with that of standard ampicillin (30 µg and chloramphenicol (30 µg. The water extract alone showed antibacterial activity against the tested organisms and the results were comparable with that of ampicillin rather than chloramphenicol.

  14. Treatment of enteric fever in children on the basis of current trends of antimicrobial susceptibility of Salmonella enterica serovar typhi and paratyphi A

    Directory of Open Access Journals (Sweden)

    Manchanda V

    2006-01-01

    Full Text Available Purpose: Recent reports indicate decreased susceptibility of S. typhi to fluoroquinolones, especially ciprofloxacin. Chloramphenicol has been suggested as first line therapy of enteric fever in many studies. This is a prospective study that describes the trends of antimicrobial susceptibility of S. typhi and S. paratyphi A causing bacteraemia in children and reports therapeutic failure to ciprofloxacin and evaluates the possible use of chloramphenicol, ampicillin, ciprofloxacin and third generation cephalosporins as first line therapy in the treatment of enteric fever in children. Methods: The present study was conducted from April 2004 to March 2005 in a superspeciality children hospital at New Delhi. A total of 56 S. typhi and five S. paratyphi A isolates were obtained among the 673 blood cultures performed. Antimicrobial testing was done using disk diffusion technique (NCCLS method for 13 antimicrobials and MICs were calculated for ampicillin, ciprofloxacin, chloramphenicol and cefotaxime. Analysis of data was done using WHONET software. Results: All 56 isolates of S. typhi were sensitive to amoxycillin+clavulanate, gentamicin, cefixime, cefotaxime and ceftazidime. Multidrug resistance (MDR, resistance to three drugs was seen in 22 cases (39% and resistance to five drugs was seen in 12 cases (21%. Only two isolates were resistant to chloramphenicol (3%. MIC 90 for ampicillin, chloramphenicol, ciprofloxacin and cefotaxime were 1.0 mg/ml, 4.0 mg/ml, 64 mg/ml and 0.125 mg/ml respectively. All S. paratyphi A isolates were sensitive to ampicillin and chloramphenicol and resistant to nalidixic acid.MIC distribution data for chloramphenicol revealed elevated MIC but still in susceptible range. Conclusions: There is an urgent need for further clinical studies to evaluate response to chloramphenicol in such cases. Antimicrobial susceptibility data and MIC distribution favour use of ampicillin as a drug of choice for the treatment of enteric fever

  15. Reduction of bacterial infections in newly hatched chicks by the use of antimicrobial dips: preliminary approaches.

    Science.gov (United States)

    Barbour, E K; Nabbut, N H; Hinners, S W; Al-Nakhli, H M

    1985-01-01

    Bacteriological examination of hatchery waste eggs, identification of the isolated bacteria, and susceptibility testing against seven antimicrobial agents were used in an attempt to establish a rational basis for reducing bacterial infections in newly hatched chicks. Chloramphenicol at 1000 ppm was selected as the antibiotic for preliminary dipping trials and 0.45% iodophore (Wescodyne) was added for later trials. The control treatment consisted of formaldehyde fumigation. The following conclusions can be drawn: Hatchery waste eggs are highly contaminated (69.1%) and enterobacteriaceae predominate (26.6%). Chloramphenicol is the most effective antimicrobial tested. Dip treatments with either chloramphenicol alone or chloramphenicol plus Wescodyne result in a reduced percentage of abnormal navels (8.4% and 10.4%), as compared with 21.9% for the control treatment. Hatchability of either group of dipped eggs is reduced in comparison with fumigated eggs. Dip treatment with chloramphenicol plus Wescodyne significantly reduces the anal carrier rates for Escherichia coli, Pseudomonas aeruginosa, Salmonella spp., and Staphylococcus aureus. This treatment reduces the incidence of bacterial infection in abnormal navels to zero. PMID:3919494

  16. mRNA translation during oocyte maturation plays a key role in development of primordial germ cells in Xenopus embryos

    Indian Academy of Sciences (India)

    Bahman Zeynali; Keith E Dixon

    2004-09-01

    It is believed that cytoplasmic localization in the egg is necessary for development of primordial germ cells (PGCs) in Xenopus embryos. In this study, we sought to determine if translation of maternal mRNA during oocyte maturation is involved in the development of PGCs. Donor oocytes were collected from both stimulated (those who receive gonadotropin) and unstimulated females, artificially matured and fertilized using a host transfer technique. Using chloramphenicol (50 M and 500 M RNA), RNA translation was inhibited during oocyte maturation. Our results showed that in unstimulated embryos treated with 50 M chloramphenicol, there was a significant reduction in the number of PGCs reaching genital ridges. In stimulated embryos, however, the number of PGCs was unchanged unless a higher concentration (500 M) of chloramphenicol was used. From these results it is suggested that maternal mRNA translation during oocyte maturation plays a key role in development of PGCs.

  17. Kepekaan Eschericia coli Patogen yang Diisolasi dari Babi Penderita Kolibasilosis terhadap Antibiotik di Kecamatan Kerambitan dan Tebanan Kabupaten Tabanan, Bali

    Directory of Open Access Journals (Sweden)

    Aditya Nugraha

    2013-11-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE This study aims to determine the sensitivity pattern of E. coli isolated from pigs with colibacillosis to antibiotics. The total of 21 fecal samples was collected from pigs with white scour at the District of Kerambitan and Tabanan, the Regency of Tabanan, Bali. The isolation and identification of pathogenic E coli used Sheep Blood Agar medium, and serotype grouping of those bacteria was designated through agglutination test using serum’s antibody Polyvalent 1-5 and 6-11. The pathogenic E. coli found was then examined it`s own resistance to streptomycin, sulfamethoxazole, gentamicin, cefotaxime, and chloramphenicol according to Kirby Bouer method. The result showed that the isolates of E. coli polyvalent 1-5 were resistant to streptomycin and chloramphenicol, whereas that of polyvalent 6-11 was resistant to sulfamethoxazole, gentamicin, streptomycin and chloramphenicol.

  18. Composite bi-layered erodible films for potential ocular drug delivery.

    Science.gov (United States)

    Boateng, J S; Popescu, A M

    2016-09-01

    Bi-layered hydroxypropylmethylcellulose and Eudragit based films were formulated as potential ocular drug delivery systems using chloramphenicol as a model antibiotic. Films were plasticized with polyethylene glycol 400 present in the Eudragit layer or both Eudragit and hydroxypropylmethylcellulose layers, and loaded with chloramphenicol (0.5% w/v in solution) in the hydroxypropylmethylcellulose layer. The weight, thickness and folding endurance of the optimized formulations were measured and further characterised for transparency, tensile, mucoadhesive, swelling and in vitro drug dissolution properties. The physical form of chloramphenicol within the films was evaluated using differential scanning calorimetry (DSC), and X-ray diffraction (XRD), complimented with scanning electron microscopy and energy dispersive X-ray spectroscopy. Fourier transform infrared spectroscopy was used to assess the interactions between the drug and the film components and confirm chloramphenicol's presence within the sample. Optimum films showed high transparency (≥80% transmittance), ease of peeling from Petri dish and folding endurance above 250. Average thickness was lower than contact lenses (0.4-1mm), confirming them as thin ocular films. The tensile properties showed a good balance between toughness and flexibility, and mucoadhesivity showed that they could potentially adhere to the ocular surface for prolonged periods. The drug loaded films showed swelling capacity that was greater than 300% of their original weight. The physical form of chloramphenicol within the films was amorphous (DSC and XRD) whilst in vitro drug dissolution showed sustained drug release from the films for four hours, before complete erosion. The chloramphenicol loaded films represent a potential means of treating common eye infections. PMID:27214785

  19. Changing trends in antimicrobial resistance of Salmonella enterica serovar typhi and salmonella enterica serovar paratyphi A in Chennai

    Directory of Open Access Journals (Sweden)

    Krishnan Padma

    2009-10-01

    Full Text Available Background and Objectives: Chloramphenicol was considered the anti-microbial gold standard for typhoid treatment but, following the increasing worldwide frequency of antibiotic resistance, ciprofloxacin has been the mainstay of therapy since 1980. Recent studies have shown a shifting of susceptibility to conventional drugs like chloramphenicol, ampicillin and cotrimoxazole. The primary objective of the study was to evaluate the in vitro activity of chloramphenicol and other first-line drugs in comparison with cephalosporins and quinolones. Materials and Methods: Fifty isolates of Salmonella obtained from blood culture were subjected to serotyping at the Central Research Institute, Kasauli. Phage typing and biotyping was performed at the National Phage Typing Centre, New Delhi. Antibiotic sensitivity testing was carried out for 10 drugs by the Kirby-Bauer disc diffusion method and minimum inhibitory concentration by broth microdilution for nalidixic acid, chloramphenicol, ciprofloxacin, ceftriaxone, cefixime and ofloxacin. Multi-drug-resistant (MDR strains were checked for plasmid. Results: In the present study, 70 and 30% of the isolates were Salmonella enterica serovar typhi and paratyphi A, respectively. They were highly sensitive to chloramphenicol (86%, ampicillin (84% and cotrimoxazole (88%. Highest sensitivity was seen for cephalosporins, followed by quinolones. Seventeen/21 (81% and 100% of the Salmonella enterica serovar typhi strains belonged to E1 phage type and biotype 1, respectively. Antibiogram showed 2% of the strains to be sensitive to all the drugs tested and 12% were MDR and showed the presence of plasmids. Conclusion: The study indicates reemergence of chloramphenicol-susceptible Salmonella enterica serovar typhi and paratyphi A isolates, a significant decline in MDR strains and high resistance to nalidixic acid. E1 phage type and biotype 1 are found to be most prevalent in Chennai, India.

  20. Effect of ionizing radition on conjugative R plasmid in Escherichia coli

    International Nuclear Information System (INIS)

    Five-fold cyclic gamma irradiation of E. coli strain No. 214 with conjugative R plasmid with doses of 150 Gy, with the exception of chloramphenicol, did not essentially affect the expression of the examined determinants of resistance to antimicrobial substances (tetracycline, streptomycin, chloramphenicol, canamycin, ampicillin, sulfamethoxidine). The dose of 150 Gy from the first irradiation of the strain reduced the transfer frequency of the R plasmid approximately hundred-fold. After the second up to the fourth irradiation of the strain the transfer frequency went back to approximately its original value. (author)

  1. Functional interactions within 23S rRNA involving the peptidyltransferase center

    DEFF Research Database (Denmark)

    Douthwaite, S

    1992-01-01

    A molecular genetic approach has been employed to investigate functional interactions within 23S rRNA. Each of the three base substitutions at guanine 2032 has been made. The 2032A mutation confers resistance to the antibiotics chloramphenicol and clindamycin, which interact with the 23S r...... chloramphenicol. Introduction of the domain II deletion into these double-mutation constructs gives rise to erythromycin resistance. The results are interpreted as indicating that position 2032 interacts with the peptidyltransferase loop and that there is a functional connection between domains II and V....

  2. The roles of different repair mechanisms in the ultraviolet resistance of Micrococcus luteus

    International Nuclear Information System (INIS)

    In ultraviolet-irradiated Micrococcus luteus wild type the replication of DNA was not interrupted at every pyrimidine dimer, in contrast to that in ultraviolet-sensitive G7 and some other mutants. The contribution of uninterrupted replication to the ultraviolet resistance of M. luteus proved to be equal to the contributions of excision repair and inducible postreplication repair. It was found that some postreplication gaps could be filled by constitutive pathways of postreplication repair when inducible pathways were suppressed by chloramphenicol. Prolonged treatment with chloramphenicol was shown to block not only inducible repair but also other processes essential for ultraviolet irradiation survival. (Auth.)

  3. Influence of incubation conditions on the anoxic survival of marine bivalves. Static and semi-static incubations

    NARCIS (Netherlands)

    De Zwaan, A.; Cattani, O.; Vitali, G.; Cortesi, P.

    2001-01-01

    In a comparative study of 4 bivalve species we show that the apparent widely different tolerances in survival time observed in a closed system filled with N-2-gassed seawater is mainly due to the experimental conditions. Both a high dose of cadmium and the antibiotic chloramphenicol increase surviva

  4. Occurrence of integrons and resistance genes among sulphonamide-resistant Shigella spp. from Brazil

    DEFF Research Database (Denmark)

    Peirano, G.; Agersø, Yvonne; Aarestrup, Frank Møller;

    2005-01-01

    2214 bp harbouring a gene cassette array conferring resistance to trimethoprim, streptothricin and spectinomycin/streptomycin. The genes coding for resistance to chloramphenicol (catA1), tetracycline [tet(A) and tet(B)] and ampicillin (bla(OXA) and bla(TEM)), were detected in resistant strains...

  5. Prevalence of antimicrobial residues in eggs, tissue and feed samples in the State of Kuwait

    International Nuclear Information System (INIS)

    A total of 238 locally produced and imported eggs, tissue (meat, poultry and aquacultured fish) and feed and feedstuffs samples were collected at different seasonal periods from different farms and retail outlets in Kuwait and screened for presence of beta-lactams, tetracyclines, sulfonamides, streptomycin, macrolides and chloramphenicol (799 tests) using Charm II system. The results indicated that all of the 222 tests performed on table egg samples were negative for the analyzed antimicrobial residues indicating adherence to the guidelines for microbial use and withdrawal. Similarly, all of the 268 tests performed on tissue samples were negative for the analyzed antimicrobial residues except for chloramphenicol. These chloramphenicol positive samples, all of the 66 tests performed were negative for beta-lactams residues. Out of the 79 feed and feedstuff samples analyzed for teracyclines residues, broiler diet and concentrate samples (5%) were above the tetracyclines MRL (100 ppb.). On the other hands, results have revealed a widespread of sulfonamide residues and to a less extent chloramphenicol in tested feed and feedstuff samples. The Charm II system was reliable for rapid screening of antimicrobial residues. In general, results obtained in our study necessitate more effective and well planned national antimicrobial residues surveillance programs focusing particularly on samples imported from highly risk sources. (author)

  6. R-plasmic transfer from Serratia liquefaciens to Escherichia coli in vitro and in vivo in the digestive tract of gnotobiotic mice associated with human fecal flora.

    OpenAIRE

    Duval-Iflah, Y; Raibaud, P; Tancrede, C; Rousseau, M.

    1980-01-01

    It was shown that a strain of Serratia liquefaciens harbors a conjugative R-plasmid responsible for reistance to the following 14 antibiotics: ampicillin, carbenicillin, cephalothin, butirosin, neomycin, paramomycin, kanamycin, lividomycin, gentamicin, tobramycin, streptomycin, tetracycline, sulfonamide, and chloramphenicol, which belong to five families, the beta-lactamines, the aminoglycosides, the tetracyclines, the sulfonamides, and the phenicols. Resistance to th 14 antibiotics was cotra...

  7. Gene expression in isolated plastids from fruits of capsicum annum

    International Nuclear Information System (INIS)

    Plastids were obtained from the ripening fruits of Capsicum annum, and incubated in vitro in the presence of [35S]methionine(Met). There was polypeptide synthesis at all stages of pepper tissue studied in both chloroplasts and chromoplasts, dependent on the addition of nuclioside triphosphates and phosphoenolpyruvate and inhibited by D-threo-chloramphenicol. l8. refs. (author)

  8. Studies on the chemical control of psychrophilic bacterial spoilage of fish. 2 - The effect of antibiotics on the growth of psycrophilic bacteria isolated from marine fish

    OpenAIRE

    Anand, C.P.; Rudra Setty, T.M.

    1981-01-01

    Among the various antibiotics tried, tetracyclines particularly chlorotetracycline (CTC), chloramphenicol and chlorostrep were found to be fairly effective at 8 and 10 p.p.m. levels. The order of sensitivity to CTC among the six genera studied was found to be Achromobacter

  9. Antimicrobial Susceptibility and Clinical Sources of Dolosigranulum pigrum Cultures

    OpenAIRE

    LaClaire, L.; Facklam, R

    2000-01-01

    Antimicrobial susceptibilities of 27 clinical isolates of Dolosigranulum pigrum were determined. All were susceptible to amoxicillin, cefotaxime, cefuroxime, clindamycin, levofloxacin, meropenem, penicillin, quinupristin-dalfopristin, rifampin, tetracycline, and vancomycin. Fifteen of the isolates were intermediate to chloramphenicol. One isolate was resistant to trimethoprim-sulfamethoxazole. Two isolates were susceptible, 10 were intermediate, and 15 were resistant to erythromycin.

  10. Antimicrobial Activity of Quinupristin-Dalfopristin Combined with Other Antibiotics against Vancomycin-Resistant Enterococci

    OpenAIRE

    Eliopoulos, G M; Wennersten, C B

    2002-01-01

    Interactions between quinupristin-dalfopristin and six other antimicrobials were examined by checkerboard arrays against 50 clinical isolates of vancomycin-resistant Enterococcus faecium selected to represent a range of susceptibilities to individual agents. Unequivocal synergistic or antagonistic interactions at clinically relevant concentrations were infrequently encountered when the streptogramin was combined with chloramphenicol, ampicillin, imipenem, vancomycin, or teicoplanin. Combinati...

  11. Linezolid Resistance in Staphylococcus aureus: Gene Dosage Effect, Stability, Fitness Costs, and Cross-Resistances▿

    OpenAIRE

    Besier, Silke; Ludwig, Albrecht; Zander, Johannes; Brade, Volker; Wichelhaus, Thomas A.

    2008-01-01

    Linezolid resistance in Staphylococcus aureus is typically associated with mutations in the 23S rRNA gene. Here we show that the accumulation of a single point mutation, G2576T, in the different copies of this gene causes stepwise increases in resistance, impairment of the biological fitness, and cross-resistance to quinupristin-dalfopristin and chloramphenicol.

  12. Anoxic survival of Macoma balthica: the effect of antibiotics, molybdate and sulphide

    NARCIS (Netherlands)

    De Zwaan, A.; Schaub, B.; Babarro, J.M.F.

    2001-01-01

    In anoxic semi-closed systems, the survival time of the clam Macoma balthica was compared to clams which were incubated in the presence of several antibiotics (chloramphenicol, 5- oxytetracycline hydrochloride, penicillin, streptomycin. a mix of penicillin and streptomycin and a mix of chloramphenic

  13. Antimicrobial Disk Susceptibility Testing of Leptospira spp. Using Leptospira Vanaporn Wuthiekanun (LVW) Agar

    OpenAIRE

    Wuthiekanun, Vanaporn; Amornchai, Premjit; Langla, Sayan; White, Nicholas J; Day, Nicholas P. J.; Limmathurotsakul, Direk; Peacock, Sharon J.

    2015-01-01

    Leptospira Vanaporn Wuthiekanun (LVW) agar was used to develop a disk diffusion assay for Leptospira spp. Ten pathogenic Leptospira isolates were tested, all of which were susceptible to 17 antimicrobial agents (amoxicillin/clavulanic acid, amoxicillin, azithromycin, cefoxitin, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, clindamycin, doripenem, doxycycline, gentamicin, linezolid, nitrofurantoin, penicillin, piperacillin/tazobactam, and tetracycline). All 10 isolates had no zone ...

  14. In Vitro Susceptibilities of Seven Leptospira Species to Traditional and Newer Antibiotics

    OpenAIRE

    Hospenthal, Duane R.; Murray, Clinton K.

    2003-01-01

    Human leptospirosis is generally treated with penicillin or doxycycline. We studied the susceptibilities of 11 serovars (seven species) of Leptospira to 14 antibiotics. With the exception of chloramphenicol, all tested agents were at least as potent as penicillin and doxycycline, with the macrolide and ketolide drugs producing the lowest MICs (and minimal bactericidal concentrations).

  15. Isolation and characterization of chromosomal promoters of Streptococcus salivarius subsp. thermophilus.

    Science.gov (United States)

    Slos, P; Bourquin, J C; Lemoine, Y; Mercenier, A

    1991-01-01

    A promoter probe vector, pTG244, was constructed with the aim of isolating transcription initiation signals from Streptococcus thermophilus (Streptococcus salivarius subsp. thermophilus). pTG244 is based on the Escherichia coli-streptococcus shuttle vector pTG222, into which the promoterless chloramphenicol acetyltransferase gene of Bacillus pumilus (cat-86) was cloned. Random Sau3A fragments from the S. thermophilus A054 chromosomal DNA were cloned upstream of the cat-86 gene by using E. coli as the host. The pool of recombinant plasmids were introduced into S. thermophilus and Lactococcus lactis subsp. lactis in order to search for promoter activity in these hosts. For S. thermophilus, it was necessary to first select erythromycin-resistant transformants and then to screen for chloramphenicol resistance among these. Direct selection of chloramphenicol-resistant clones was, however, possible in L. lactis subsp. lactis. Six fragments exhibiting promoter activity were characterized in S. thermophilus by measuring the levels of cat-86 transcription and/or chloramphenicol acetyltransferase specific activity. Three of the promoter-carrying fragments were sequenced. The 5' ends of their corresponding mRNAs were determined by S1 mapping and shown to correspond to a purine residue in all cases. Upstream from these potential transcription start points, sequences homologous to the E. coli sigma 70 and the Bacillus subtilis vegetative sigma 43 (or sigma A) consensus promoters were identified. Images PMID:1854195

  16. Antibacterial activity of mushroom Osmoporus odoratus

    OpenAIRE

    Sivakumar R; Vetrichelvan T; Rajendran N; Devi M; Sundaramoorthi K; Shankar ASK; Shanmugam S

    2006-01-01

    The petroleum ether, chloroform, acetone and water extracts of mushroom Osmoporus odoratus were selected for examine the antibacterial activity against Staphylococcus aureus, Streptococcus pyogenes, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa by disc diffusion method using Muller Hinton agar media. And the extracts were compared with that of standard ampicillin (30 µg) and chloramphenicol (30 µg). The water extract alone showed antibacterial activity aga...

  17. Unusual presentation of primary klebsiella meningitis: successful treatment with cefotaxime.

    OpenAIRE

    Sandyk, R.; Brennan, M J

    1983-01-01

    A man who presented with lumbar backache subsequently developed signs of meningitis. The causative organism was proved to be Klebsiella pneumoniae. Despite treatment with chloramphenicol and amikacin, the condition progressed until cefotaxime was added to the treatment regimen. The patient made a good recovery. This is the first report of the use of cefotaxime in klebsiella meningitis.

  18. Turnover of nitrogenase and leghemoglobin in root nodules of Pisum sativum

    NARCIS (Netherlands)

    Bisseling, T.; Straten, van J.; Houwaard, F.

    1980-01-01

    Turnover rates of the two nitrogenase components and leghemoglobin in root nodules of pea plants nodulated with Rhizobium leguminosarum were determined with three different methods: 1, Kinetics of 35S incorporation into protein; 2, pulse-chase experiments; 3, chloramphenicol inhibition of bacteroid

  19. Antibiotic resistance and resistance genes in Escherichia coli from poultry farms, southwest Nigeria

    DEFF Research Database (Denmark)

    Adelowo, Olawale O.; Fagade, Obasola E.; Agersø, Yvonne

    2014-01-01

    %, ampicillin 36%, spectinomycin 28%, nalidixic acid 25%, chloramphenicol 22%, neomycin 14%, gentamicin 8%, amoxicillin-clavulanate, ceftiofur, cefotaxime, colistin, florfenicol and apramycin 0%. Resistance genes found among the isolates include bla-TEM (85%), sul2 (67%), sul3 (17%), aadA (65%), strA (70%), str...

  20. Flow Cytometric Determination of the Effects of Antibacterial Agents on Mycoplasma agalactiae, Mycoplasma putrefaciens, Mycoplasma capricolum subsp. capricolum, and Mycoplasma mycoides subsp. mycoides Large Colony Type

    OpenAIRE

    Assunção, Patricia; Antunes, Nuno T.; Rosales, Ruben S.; Poveda, Carlos; Poveda, Jose B.; Davey, Hazel M.

    2006-01-01

    Flow cytometry together with SYBR green I and propidium iodide was used to study the effects of enrofloxacin, ciprofloxacin, gentamicin, chloramphenicol, oxytetracycline, and tylosin on four mycoplasma species. Inhibition of mycoplasma growth could be detected by as early as 3 h after the start of treatment. The strongest effect was observed with enrofloxacin- and ciprofloxacin-treated cells.

  1. Identification of Diverse Antimicrobial Resistance Determinants Carried on Bacterial, Plasmid, or Viral Metagenomes from an Activated Sludge Microbial Assemblage▿

    OpenAIRE

    Parsley, Larissa C.; Consuegra, Erin J.; Kakirde, Kavita S.; Land, Andrew M.; Harper, Willie F.; Liles, Mark R.

    2010-01-01

    Using both sequence- and function-based metagenomic approaches, multiple antibiotic resistance determinants were identified within metagenomic libraries constructed from DNA extracted from bacterial chromosomes, plasmids, or viruses within an activated sludge microbial assemblage. Metagenomic clones and a plasmid that in Escherichia coli expressed resistance to chloramphenicol, ampicillin, or kanamycin were isolated, with many cloned DNA sequences lacking any significant homology to known ant...

  2. Antimicrobial susceptibility and Ribosomal-RNA gene restriction patterns among Staphylococcus-intermedius from healthy dogs and from dogs sufferning from pyoderma or otitis-externa

    DEFF Research Database (Denmark)

    Pedersen, Karl; Wegener, Henrik Caspar

    1995-01-01

    10 strains from a previous study. Sixty per cent of the 50 strains tested for antibiotic susceptibility demonstrated resistance to penicillin, 24% to spiramycin, 20% to tetracycline, 16% to chloramphenicol, and 2% to fucidic acid, All isolates were susceptible to amoxycillin with clavulanic acid...

  3. Genetic control of multiple pathways of post-replicational repair in uvrB strains of Escherichia coli K-12

    International Nuclear Information System (INIS)

    The effect of the recA, uvrD, exrA, and recB mutations and of post-irradiation treatment with chloramphenicol on the survival and post-replicational repair after ultraviolet irradiation of uvrB strains of Escherichia coli K-12 was examined. Each of these mutations or treatments was found to decrease survival and the extent of repair. The interactions of the inhibitory effects of the uvrD, exrA, and recB mutations and chloramphenicol treatment were determined by examining the survival and repair characteristics of the several multiple mutants. The survival results suggest that the post-replication repair process in uvrB strains may be subdivided into at least five different branches. These include three branches that are blocked by the exrA, recB, or uvrD mutation, a fourth branch that is blocked by any one of these mutations and is also sensitive to chloramphenicol treatment, and at least one additional branch that is not sensitive to either of these mutations or to chloramphenicol treatment. The extent of post-replicational repair observed with each of the strains is in general agreement with the pathways postulated on the basis of the survival data, although there are several apparent exceptions to this correlation

  4. Antibiotic Resistance in Diarrheagenic Escherichia coli and Shigella Strains Isolated from Children in Hanoi, Vietnam

    OpenAIRE

    Nguyen, Trung Vu; Le Van, Phung; Le, Chinh Huy; Weintraub, Andrej

    2005-01-01

    The MICs for 162 diarrheagenic Escherichia coli strains and 28 Shigella strains were determined on the basis of NCCLS guidelines. More than 75% of the strains were resistant to ampicillin, chloramphenicol (53.6% of Shigella strains), and trimethoprim-sulfamethoxazole. Multiresistance was detected in 89.5% of E. coli strains and 78.6% of Shigella strains.

  5. Synthesis and biological activity of nifuroxazide and analogs.

    Science.gov (United States)

    Tavares, L C; Penna, T C; Amaral, A T

    1997-03-01

    Nifuroxazide and thirteen analogs were synthesized from substituted benzoic acids and minimal inhibitory concentrations were determined using the serial dilution tests, in three sequential steps. Nifuroxazide and chloramphenicol were used as reference standards. The tests were performed in TSB against the standard bacterial strain of Staphylococcus aureus ATCC 25923. PMID:9164164

  6. Radiation sterilization of plasticized PVC and some pharmaceuticals

    International Nuclear Information System (INIS)

    A variety of medical products/containers fabricated from plastics, and pharmaceuticals are being sterilized by gamma radiation at ISOMED, Bhabha Atomic Research Centre, Bombay. The chromatographic behaviour and UV absorption spectra of aquo/organic extracts from PVC based transfusion assemblies after radiation treatment and the effect of irradiation on urea, chloramphenicol, tetracycline and ophthalmic ointment bases are discussed. (auth.)

  7. Research within the coordinated programme on practices for the radiation sterilization of medical supplies in countries of Asia and the Pacific Region

    International Nuclear Information System (INIS)

    The results are presented of a four year coordinated research programme related to: effects of gamma radiation on chloramphenicol and hydrocortisone acetate mixture eye ointment, methodology of biological dosimetry, radiation sterilization dose setting using fraction positive and most resistant microbes, effects of gamma radiation on neomycin sulphate and procaine penicillin G in solid state, and calibration of panoramic batch irradiation using Ceric dosemeter

  8. Drug-susceptibility of isolates of Brachyspira hyodysenteriae isolated from colonic mucosal specimens of pigs collected from slaughter houses in Japan in 2009.

    Science.gov (United States)

    Kajiwara, Keita; Kozawa, Midori; Kanazawa, Takuya; Uetsuka, Kouji; Nakajima, Hiromi; Adachi, Yoshikazu

    2016-04-01

    Twenty nine isolates identified as Brachyspira hyodysenteriae were most susceptible to carbadox and metronidazole, whereas they were resistant to macrolides. The isolates showed intermediate susceptibility to tiamulin, lincomycin, penicillin G, ampicillin, chloramphenicol, tetracycline, enrofloxacin and valnemulin, with MIC50 values ranging from 0.39 to 3.13. PMID:26596637

  9. Influence Of Quinolone Lethality on Irradiated Anaerobic Growth of Escherichia Coli

    International Nuclear Information System (INIS)

    Bacteriostatic and bactericidal activities were measured with wild type cells and isomerase mutants of Escherichia coli for ciprofloxacin, formation of quinolone-gyrase-DNA complexes, observed as a sodium dodecyl sulfate (SDS) dependent drop in cell lysate viscosity, occurred during aerobic and anaerobic growth and in the presence and in the absence of chloramphenicol. Quinolone activity against Escherichia coli was examined during aerobic growth, aerobic treatment with chloramphenicol, and anaerobic growth. Nalidixic acid, norfloxacin and ciprofloxacin were lethal for cultures growing aerobically, and the bacteriostatic activity of each quinolone was unaffected by anaerobic growth. However, lethal activity was distinct for each quinolone with cells treated aerobically with chloramphenicol or grown anaerobically. Nalidixic acid failed to kill cells under both conditions, norfloxacin killed cells when they were grown anaerobically but not when they were treated with chloramphenicol, ciprofloxacin killed cells under both conditions but required higher concentrations than those required with cells grown aerobically, C-methoxy fluoro quinolone was equally lethal under all conditions. However, lethal chromosome fragmentation, detected as a drop in viscosity in the absence of SDS, was occurred with nalidixic acid treatment only under aerobic conditions in the absence of chloramphenicol, thus, all quinolones tested appeared to form reversible bacteriostatic complexes containing broken DNA during aerobic growth, during anaerobic growth, and when protein synthesis is blocked. The ability to fragment chromosomes rapidly kill cells under these conditions depends on quinolone structure. The radiation of sublethal dose was 3 Gy at rate of 0.6 Gy/min was shown as non-significant result

  10. The in vitro activity of 15 antimicrobial agents against bacterial isolates from dogs.

    Science.gov (United States)

    Awji, Elias Gebru; Damte, Dereje; Lee, Seung-Jin; Lee, Joong-Su; Kim, Young-Hoan; Park, Seung-Chun

    2012-08-01

    The in vitro activity of 15 antimicrobial agents against clinical isolates of Staphylococcus pseudintermedius, Staphylococcus aureus, Escherichia coli, Pasteurella spp. and Streptococcus canis from dogs was investigated. For Staphylococcus spp., the highest frequency of resistance was observed for penicillin, followed by ampicillin, tetracycline and chloramphenicol. The highest frequency of resistance in E. coli isolates was recorded for tetracycline and streptomycin. Pasteurella spp. and S. canis had the highest resistance rate for tetracycline and chloramphenicol. Most isolates showed full susceptibility to low-level resistance to colistin, florfenicol and fluoroquinolones. Further studies using larger number of isolates from both healthy and diseased dogs would provide a broader picture of antimicrobial resistance at a national level and promote prudent use of antimicrobial agents in companion animals. PMID:22516694

  11. Antibiotic susceptibility profile of Aeromonas spp. isolates from food in Abu Dhabi, United Arab Emirates.

    Science.gov (United States)

    Awan, Mohammad Bashir; Maqbool, Ahmed; Bari, Abdul; Krovacek, Karel

    2009-01-01

    A total of 57 Aeromonas isolates from food samples such as fresh and frozen chicken, game birds, pasteurized milk, baby food, bakery products, fruit and vegetables, fish, and water from Abu Dahbi, UAE were investigated for antibiotic susceptibility profile. Most strains were resistant to penicillins (ticarcillin, mezlocillin, oxacillin, piperacillin), sulfamethoxazole, trimethoprim and macrolides (erythromycin, vancomycin, clindamycin) but sensitive to tetracycline, chloramphenicol, nitrofurantoin, aminoglycosides (amikacin, gentamicin, tobramycin), cephalosporins (cefuroxime, ceftrioxone, cefazolin, cephalexin, cephalothin, cefoxitin, cefotaxime), quinolone (ciprofloxacin), colistin sulphate and SXT (trimethoprim-sulfamethoxazole). On the other hand, many antibiotics showed excellent inhibitory activity (>75% strains were sensitive to them) against all the strains tested. These include cefuroxime, ceftrioxone, ciprofloxacin, colistin, amikacin, gentamicin, tetracycline, chloramphenicol, nitrofurantoin, cefotaxime and tobramycin. In conclusion, the results show a detailed pattern of sensitivity of the various Aeromonas spp. isolates to a variety of antibiotics and provide useful information in the context of selective isolation and phenotypic identification of the aeromonads from food. PMID:19382665

  12. Synthesis, characterization, electrochemical studies, and in vitro antibacterial activity of novel thiosemicarbazone and its Cu(II), Ni(II), and Co(II) complexes.

    Science.gov (United States)

    Khan, Salman A; Asiri, Abdullah M; Al-Amry, Khalid; Malik, Maqsood Ahmad

    2014-01-01

    Metal complexes were prepared by the reaction of thiosemicarbazone with CuCl2, NiCl2, CoCl2, Cu(OAc)2, Ni(OAc)2, and Co(OAc)2. The thiosemicarbazone coordinates to metal through the thionic sulfur and the azomethine nitrogen. The thiosemicarbazone was obtained by the thiosemicarbazide with 3-acetyl-2,5-dimethylthiophene. The identities of these compounds were elucidated by IR, (1)H, (13)C-NMR, and GC-MS spectroscopic methods and elemental analyses. The antibacterial activity of these compounds was first tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC) was determined by using chloramphenicol as reference drug. The results showed that compound 1.1 is better inhibitor of both types of tested bacteria as compared to chloramphenicol. PMID:24523641

  13. [Standardization of the Neisseria meningitidis antibiogram. Detection of strains relatively resistant to penicillin].

    Science.gov (United States)

    Nicolas, P; Cavallo, J D; Fabre, R; Martet, G

    1998-01-01

    Studying the susceptibility of 189 Neisseria meningitidis strains to penicillin, amoxicillin, cefotaxime, ceftriaxone, chloramphenicol and rifampicin by determination of minimum inhibitory concentrations (MICs) by agar dilution (reference method), E-test and disc diffusion method on Mueller-Hinton agar at 37 degrees C with 5% CO2 enabled us to standardize the antibiograms. While MIC determination by agar dilution is still the reference method, it is possible to obtain exact or approximate MIC values using the E-test. For laboratories that cannot determine penicillin MICs, it is impossible to detect strains that are relatively resistant to penicillin (RRP strains: 0.1 oxacillin disc allows MIC to be determined in most cases when the oxacillin inhibition zone is pharmacokinetics, we propose critical concentrations for these various antibiotics as well as critical diameters for chloramphenicol and rifampicin discs. PMID:9803590

  14. Synthesis, Characterization, Electrochemical Studies, and In Vitro Antibacterial Activity of Novel Thiosemicarbazone and Its Cu(II, Ni(II, and Co(II Complexes

    Directory of Open Access Journals (Sweden)

    Salman A. Khan

    2014-01-01

    Full Text Available Metal complexes were prepared by the reaction of thiosemicarbazone with CuCl2, NiCl2, CoCl2, Cu(OAc2, Ni(OAc2, and Co(OAc2. The thiosemicarbazone coordinates to metal through the thionic sulfur and the azomethine nitrogen. The thiosemicarbazone was obtained by the thiosemicarbazide with 3-acetyl-2,5-dimethylthiophene. The identities of these compounds were elucidated by IR, 1H, 13C-NMR, and GC-MS spectroscopic methods and elemental analyses. The antibacterial activity of these compounds was first tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC was determined by using chloramphenicol as reference drug. The results showed that compound 1.1 is better inhibitor of both types of tested bacteria as compared to chloramphenicol.

  15. Multiple drug resistance of Aeromonas hydrophila isolates from Chicken samples collected from Mhow and Indore city of Madhyapradesh

    Directory of Open Access Journals (Sweden)

    Kaskhedikar

    2009-02-01

    Full Text Available Fourteen antibacterial agents belonging to 9 different groups of antibiotics viz. aminoglycosides, cephalosporins, nitrofurantoin, fluroquinolones, chloramphenicol, sulphonamides, tetracyclines, penicillin and polymixin were used for in vitro sensitivity testing of Aeromonas hydrophila isolated from fifteen samples of chicken collected from retail shops in Mhow city. The sensitivity (100% was attributed to ciprofloxacin, cefuroxime, ceftriaxone, cephotaxime, chloramphenicol, gentamycin, kanamycin, nitrofurantoin, nalidixic acid and ofloxacin followed by oxytetracycline (50%. All the isolates were resistant to ampicillin and colistin antibiotics. That means, none of the isolates were found to be sensitive for penicillin and polymixin group of antibiotics. Multiple drug resistance was also observed in all A. hydrophila isolates. Out of total isolates, 100% were resistant to two antimicrobial drugs and 50% to three drugs. [Vet. World 2009; 2(1.000: 31-32

  16. Prevalence of bacteriuria in Jeyaseharan Hospital of South India and their antibiogram

    Institute of Scientific and Technical Information of China (English)

    Prakash S; S Anto Jeya Dayalan; Edison N

    2011-01-01

    Objective: To investigate the prevalence of bacteriologically positive urinary tract infection (UTI) among people enrolled in the hospital during January 2010 to June 2010. Methods: In the study period, a total of 1 546 patients were screened for UTI and the antibiogram was studied. Results: A total of 744 patients were positive. It revealed that females were more vulnerable to bacteriuria than males. Organisms predominantly isolated were Esherichia coli followed byKlebsiella in both males and females. Among the antibiotics tested against the isolated organisms for sensitivity test, chloramphenicol was more effective followed by amikacin and gatifloxacin for Enterobacteriaceae. For Pseudomonas aeruginosa, chloramphenicol was not effective, amikacin was effective. Amoxycillin, amoxycillin/clavulanic acid and first generation cephalosporin were least effective against Enterobacteriaceae and Pseudomonas aeruginosa. Conclusions: This study would not only help in proper treatment of patients but also discourage the indiscriminate use of antibiotics and prevent development of drug resistance.

  17. Microcalorimetric Studies on Gene Promoter Function of Cloned DNA Fragements from Halobacterium halobium J7 Plasmid pHH205 in Escherichia coli TG1

    Institute of Scientific and Technical Information of China (English)

    LEI,Ke-Lin; HOU,Han-Na; LIU,Yi; YE,Xue-Cheng; SHEN,Ping

    2007-01-01

    Halobacterium halobium is a typical kind of extremely halophilic bacterium. Combined with the antibiotic resistance assay, the microcalorimetric method was used to study the promoter function of the cloned DNA fragments from Halobacterium halobium J7 plasmid pHH205 in Escherichia coli TG1. The promoter probe vector, plasmid pKK232-8, was used to form the recombinants. The DNA fragment, which is the promoter for the chloramphenicol acetyl transferase (CAT) gene in plasmid pKK232-8, is about 800 bp, and the chloramphenicol resistance level presented by IC50 is about 200 μg·mL-1, which suggests a high promoter activity. The conclusions show that there probably exist double-function or trinary-function gene promoters in Halobacterium halobium, and Archaea may contain rich genetic resources.

  18. Synthesis and Anti-Bacterial Activities of a Bis-Chalcone Derived from Thiophene and Its Bis-Cyclized Products

    Directory of Open Access Journals (Sweden)

    Abdullah M. Asiri

    2011-01-01

    Full Text Available A chalcone was prepared by the reaction of terephthalaldehyde with 3-acetyl-2,5-dimethylthiophene. Treatment of this chalcone with thiosemicarbazide/phenyl hydrazine/guanidine hydrochloride/thiourea afforded the corresponding pyrazoline,  pyrazole, and pyrimidine in good yields. All the new compounds have been characterized by IR, 1H-NMR, 13C-NMR, GC-MS and elemental analyses. The anti-bacterial activity of these compounds were first tested in vitro by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC was determined with the reference of standard drug chloramphenicol. The results showed that the pyrazoline derivative is better at inhibiting growth of both types of bacteria (Gram-positive and Gram-negative compared to chloramphenicol.

  19. Antibiotic Resistance Pattern Of Bacterial Pathogens Isolated From Poultry Manure Used To Fertilize Fish Ponds In New Bussa, Nigeria

    Directory of Open Access Journals (Sweden)

    Funso Omojowo

    2013-02-01

    Full Text Available This study was carried out to isolate and identify antibiotic resistant bacteria from poultry manure usually used for pond fertilization. Poultry manure from 120 Chickens in National Institute for Freshwater Fisheries Research (NIFFR integrated fish farms, New-Bussa, Nigeria was collected. Five bacterial pathogens; Salmonella typhi, Escherichia coli, Shigella dysenteriae, Staphylococcus aureus and Aeromonas hydrophila were isolated. Antibiotic susceptibility testing carried out using the disk diffusion technique. Antibiotics used were; ofloxacin, amoxicillin, tetracycline, ampicillin, erythromycin, gentamicin, nalidixic acid and chloramphenicol. All the isolated organisms were 100% sensitive to ofloxacin. The multiple resistance pattern revealed that 100% were resistant to tetracycline, 84.34% resistant to ampicillin, 76.68% resistant to amoxicillin, 66% resistant to chloramphenicol, 66% resistant to gentamicin, 29% resistant to erythromycin, 28.34% resistant to nalidixic acid. The risk posed by untreated poultry manure used in fish pond fertilization and the public health implications of these results were discussed.

  20. A Novel Method for Preparation of Gold NanoBipyramids Using Microwave Irradiation and Its Application in Immunosensors

    Science.gov (United States)

    Huynh, Trong Phat; Ngo, Vo Ke Thanh; Nguyen, Dang Giang; Nguyen, Hoang Phuong Uyen; Nghiem, Quoc Dat; Lam, Quang Vinh; Huynh, Thanh Dat

    2016-05-01

    Gold nanobipyramids (NBPs) have attracted attention for producing smart sensing devices as diagnostic tools in biotechnological and medical applications, because they show more advantageous plasmonic properties than comparable gold nanorods. Normally, NBPs were synthesized using seed-mediated growth process at room temperature. In this report, our group describes a method for synthesising of NBPs using microwave irradiation with ascorbic acid reduction and cetyltrimethylammonium bromide + silver nitrate (AgNO3) as capping agents. The advantages of this method are a highly effective approach to fast and uniform NBPs. The product was characterized by ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and x-ray powder diffraction. As an application in quartz crystal microbalance immunosensors, NBPs is conjugated with the chloramphenicol antibodies for signal amplification to detect chloramphenicol residuals in the QCM system.

  1. Effect of acriflavine on ultraviolet inactivation of Acholeplasma laidlawii

    International Nuclear Information System (INIS)

    An increased sensitivity to inactivation was observed when ultraviolet light-irradiated Acholeplasma laidlawii cells were plated on medium containing either acriflavine or chloramphenicol. Chloramphenicol reduced liquid holding recovery (dark repair) to about 10 percent of that in untreated irradiated cells. In acriflavine treated cells no dark repair could be observed and there was a progressive degradation of cell DNA during holding. While the primary effect of acriflavine may be to inhibit excision repair, since ultraviolet-irradiated Mycoplasma gallisepticum (cells which lack an excision repair machanism) show a slight increase in inactivation when plated on medium containing acriflavine, the dye must also have some other effects on ultraviolet repair processes. Acriflavine treatment of A. laidlawii cells before ultraviolet irradiation has a protective effect, as seen by an increased cell survival. (Auth.)

  2. Eco-friendly synthesis and in vitro antibacterial activities of some novel chalcones.

    Science.gov (United States)

    Khan, Salman A; Asiri, Abdullah M; Alamry, Khalid A; El-Daly, Samy A; Zayed, Mohie A M

    2013-01-01

    Chalcone derivatives have been synthesized by reaction of 1-(2,5-dimethyl-furan-3-yl)-ethanone with corresponding active aldehyde in ethanolic NaOH in microwave oven. The structure of these compounds was established by elemental analysis, IR, 1H-NMR, 13C-NMR, and EI-MS spectral analysis. The anti-bacterial activity of these compounds was first tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC) was determined with the reference of standard drug Chloramphenicol. The results showed that pyrazol containing chalcone (compound 8) inhibited both types of bacteria (Gram-positive and Gram-negative) better than chloramphenicol. PMID:24397034

  3. An alkylaminoquinazoline restores antibiotic activity in Gram-negative resistant isolates.

    Science.gov (United States)

    Mahamoud, Abdallah; Chevalier, Jacqueline; Baitiche, Milad; Adam, Elissavet; Pagès, Jean-Marie

    2011-02-01

    To date, various bacterial drug efflux pump inhibitors (EPIs) have been described. They exhibit variability in their activity spectrum with respect to antibiotic structural class and bacterial species. Among the various 4-alkylaminoquinazoline derivatives synthesized and studied in this work, one molecule, 1167, increased the susceptibility of important human-pathogenic, resistant, Gram-negative bacteria towards different antibiotic classes. This 4-(3-morpholinopropylamino)-quinazoline induced an increase in the activity of chloramphenicol, nalidixic acid, norfloxacin and sparfloxacin, which are substrates of the AcrAB-TolC and MexAB-OprM efflux pumps that act in these multidrug-resistant isolates. In addition, 1167 increased the intracellular concentration of chloramphenicol in efflux pump-overproducing strains. The rate of restoration depended on the structure of the antibiotic, suggesting that different sites in the efflux pumps may be involved. A molecule exhibiting a morpholine functional group and a propyl extension of the side chain was more active. PMID:21071494

  4. Shedding of antibiotic-resistant members of the family Enterobacteriaceae in healthy residents of France and Jordan.

    Science.gov (United States)

    Chachaty, E; Youssef, M T; Bourneix, C; Andremont, A

    1995-02-01

    We compared the frequency of shedding of members of the family Enterobacteriaceae resistant to ampicillin, tetracycline, chloramphenicol, kanamycin, gentamicin and ceftazidime in 83 French residents of the Paris urban area and in 101 subjects in Jordan, 64 of whom resided in the urban area of Irbid, 15 in rural areas, and 22 of whom had a nomadic lifestyle. There was no significant difference between these populations regarding (i) the percentages of subjects with strains resistant to any of the antimicrobial agents tested and (ii) the proportions of total counts of organisms of the Enterobacteriaceae resistant to these agents. The simultaneous shedding of strains resistant to ampicillin, chloramphenicol, tetracycline and kanamycin was significantly associated with (i) exposure to antibiotic treatment during the six months preceding the study and (ii) the presence of many children at home. PMID:7652211

  5. Altered synthetic response of Campylobacter jejuni to cocultivation with human epithelial cells is associated with enhanced internalization.

    Science.gov (United States)

    Konkel, M E; Cieplak, W

    1992-01-01

    Campylobacter jejuni has been shown to bind to and enter epithelial cells in culture. The interaction of C. jejuni with INT 407 epithelial cells was examined to determine whether bacterial protein synthesis is required for either binding or internalization. Chloramphenicol, a selective inhibitor of bacterial protein synthesis, significantly reduced the internalization, but not binding, of C. jejuni compared with untreated controls as determined by protection from gentamicin. Electrophoretic analysis of metabolically labeled proteins revealed that C. jejuni cultured with INT 407 cells synthesized 14 proteins that were not detected in organisms cultured in medium alone. The inhibitory effect of chloramphenicol on internalization was reduced by preincubation of C. jejuni with INT 407 cells. The results indicate that C. jejuni, like some other enteric pathogens, engages in a directed response to cocultivation with epithelial cells by synthesizing one or more proteins that facilitate internalization and suggest that this phenomenon is relevant to the pathogenesis of enteritis caused by C. jejuni. Images PMID:1399005

  6. Effects of UV light disinfection on antibiotic-resistant coliforms in wastewater effluents

    International Nuclear Information System (INIS)

    Total coliforms and total coliforms resistant to streptomycin, tetracycline, or chloramphenicol were isolated from filtered activated sludge effluents before and after UV light irradiation. Although the UV irradiation effectively disinfected the wastewater effluent, the percentage of the total surviving coliform population resistant to tetracycline or chloramphenicol was significantly higher than the percentage of the total coliform population resistant to those antibiotics before UV irradiation. This finding was attributed to the mechanism of R-factor mediated resistance to tetracycline. No significant difference was noted for the percentage of the surviving total coliform population resistant to streptomycin before or after UV irradiation. Multiple drug resistant to patterns of 300 total coliform isolates revealed that 82% were resistant to two or more antibiotics. Furthermore, 46% of these isolates were capable of transferring antibiotic resistance to a sensitive strain of Escherichia coli

  7. Genetic improvement of Escherichia coli for ethanol production: chromosomal integration of Zymomonas mobilis genes encoding pyruvate decarboxylase and alcohol dehydrogenase II.

    OpenAIRE

    Ohta, K.; Beall, D S; Mejia, J P; Shanmugam, K. T.; Ingram, L O

    1991-01-01

    Zymomonas mobilis genes for pyruvate decarboxylase (pdc) and alcohol dehydrogenase II (adhB) were integrated into the Escherichia coli chromosome within or near the pyruvate formate-lyase gene (pfl). Integration improved the stability of the Z. mobilis genes in E. coli, but further selection was required to increase expression. Spontaneous mutants were selected for resistance to high level of chloramphenicol that also expressed high levels of the Z. mobilis genes. Analogous mutants were selec...

  8. Foot-and-mouth disease virus 2A oligopeptide mediated cleavage of an artificial polyprotein.

    OpenAIRE

    Ryan, M. D.; J. Drew

    1994-01-01

    We describe the construction of a plasmid (pCAT2AGUS) encoding a polyprotein in which a 19 amino acid sequence spanning the 2A region of the foot-and-mouth disease virus (FMDV) polyprotein was inserted between the reporter genes chloramphenicol acetyl transferase (CAT) and beta-glucuronidase (GUS) maintaining a single, long open reading frame. Analysis of translation reactions programmed by this construct showed that the inserted FMDV sequence functioned in a manner similar to that observed i...

  9. Influence of incubation conditions on the anoxic survival of marine bivalves. Static and semi-static incubations

    OpenAIRE

    Zwaan, A.; Cattani, O; Vitali, G.; Cortesi, P

    2001-01-01

    In a comparative study of 4 bivalve species we show that the apparent widely different tolerances in survival time observed in a closed system filled with N-2-gassed seawater is mainly due to the experimental conditions. Both a high dose of cadmium and the antibiotic chloramphenicol increase survival time 2- to 4-fold. Without precautions for bacterial growth, the survival time of the most tolerant species, Scapharca inaequivalvis, is about 4 times longer than that of the most sensitive speci...

  10. Aminoglycoside Efflux in Pseudomonas aeruginosa: Involvement of Novel Outer Membrane Proteins

    OpenAIRE

    Jo, James T. H.; Brinkman, Fiona S.L.; Hancock, Robert E W

    2003-01-01

    The expression of tripartite multidrug efflux pumps such as MexA-MexB-OprM in Pseudomonas aeruginosa contributes to intrinsic resistance to a wide variety of antimicrobials, including β-lactams, chloramphenicol, macrolides, quinolones, and tetracycline. The MexX-MexY linker-pump combination has been shown to be involved in intrinsic resistance to aminoglycosides, but the identity of the cognate outer membrane channel component remains under debate. Fourteen uncharacterized OprM homologs ident...

  11. pH-sensitive immunoliposomes mediate target-cell-specific delivery and controlled expression of a foreign gene in mouse.

    OpenAIRE

    Wang, C Y; Huang, L

    1987-01-01

    A plasmid containing the Escherichia coli chloramphenicol acetyltransferase (CAT) gene under the control of a mammalian cAMP-regulated promoter was entrapped in H-2Kk antibody-coated liposomes composed of dioleoyl phosphatidylethanolamine, cholesterol, and oleic acid (pH-sensitive immunoliposomes). The entrapped or free DNA was injected intraperitoneally into immunodeficient (nude) BALB/c mice bearing ascites tumor generated by H-2Kk-positive RDM-4 lymphoma cells. About 20% of the injected im...

  12. Herpes simplex virus virion stimulatory protein mRNA leader contains sequence elements which increase both virus-induced transcription and mRNA stability.

    OpenAIRE

    Blair, E D; Blair, C C; Wagner, E K

    1987-01-01

    To investigate the role of 5' noncoding leader sequence of herpes simplex virus type 1 (HSV-1) mRNA in infected cells, the promoter for the 65,000-dalton virion stimulatory protein (VSP), a beta-gamma polypeptide, was introduced into plasmids bearing the chloramphenicol acetyltransferase (cat) gene together with various lengths of adjacent viral leader sequences. Plasmids containing longer lengths of leader sequence gave rise to significantly higher levels of CAT enzyme in transfected cells s...

  13. The proteolysis of mitotic cyclins in mammalian cells persists from the end of mitosis until the onset of S phase.

    OpenAIRE

    Brandeis, M.; Hunt, T

    1996-01-01

    We have studied how the cell cycle-specific oscillations of mitotic B-type cyclins are generated in mouse fibroblasts. A reporter enzyme comprising the N-terminus of a B-type cyclin fused to bacterial chloramphenicol acetyl transferase (CAT) was degraded at the end of mitosis like endogenous cyclins. Point mutations in the destruction box of this construct completely abolished its mitotic instability. When the destructible reporter was driven by the cyclin B2 promoter, CAT activity mimicked t...

  14. Cytoplasmic sequestration of an O6-methylguanine-DNA methyltransferase enhancer binding protein in DNA repair-deficient human cells

    OpenAIRE

    Frank Y. Chen; Harris, Linda C.; Joanna S Remack; Brent, Thomas P.

    1997-01-01

    O6-Methylguanine-DNA methyltransferase (MGMT), an enzyme that repairs adducts at O6 of guanine in DNA, is a major determinant of susceptibility to simple methylating carcinogens or of tumor response to anticancer chloroethylating drugs. To investigate the mechanisms underlying cellular expression of this DNA repair enzyme, we focused on the role of a 59-bp enhancer of the human MGMT gene in the regulation of its expression. By using chloramphenicol acetyltransferase reporter assays, we found ...

  15. Expression Level of IL-6 Secreted by Bone Marrow Stromal Cells in Mice with Aplastic Anemia

    OpenAIRE

    Yong Feng Chen; Zhong Min Wu; Cong Xie; Shi Bai; Li Dong Zhao

    2013-01-01

    Parasecretion of the hematopoietic cytokines is considered as one of the mechanisms account for bone marrow hematopoiesis disorder. In this study, the level of IL-6 secreted by bone marrow stromal cells from a mouse model of aplastic anemia was analyzed. The aplastic anemia mouse model was established with cyclophosphamide in combination with chloramphenicol and 60Co γ radiation. The impairment of bone marrow hematopoiesis induced by irradiation and chemotherapeutic drugs was subsequently cha...

  16. Expression and purification of recombinant proteins from Escherichia coli: Comparison of an elastin-like polypeptide fusion with an oligohistidine fusion

    OpenAIRE

    Trabbic-Carlson, Kimberly; Liu, Li; Kim, Bumjoon; Chilkoti, Ashutosh

    2004-01-01

    Thermally responsive elastin like polypeptides (ELPs) can be used to purify proteins from Escherichia coli culture when proteins are expressed as a fusion with an ELP. Nonchromatographic purification of ELP fusion proteins, termed inverse transition cycling (ITC), exploits the reversible soluble–insoluble phase transition behavior imparted by the ELP tag. Here, we quantitatively compare the expression and purification of ELP and oligohistidine fusions of chloramphenicol acetyltransferase (CAT...

  17. Highly stable expression of a foreign gene from rabies virus vectors.

    OpenAIRE

    Mebatsion, T; Schnell, M J; Cox, J H; Finke, S; Conzelmann, K K

    1996-01-01

    A reverse genetics approach was applied to generate a chimeric nonsegmented negative strand RNA virus, rabies virus (RV) of the Rhabdoviridae family, that expresses a foreign protein. DNA constructs containing the entire open reading frame of the bacterial chloramphenicol acetyltransferase (CAT) gene and an upstream RV cistron border sequence were inserted either into the nontranslated pseudogene region of a full-length cDNA copy of the RV genome or exchanged with the pseudogene region. After...

  18. Animal and Human Multidrug-Resistant, Cephalosporin-Resistant Salmonella Isolates Expressing a Plasmid-Mediated CMY-2 AmpC β-Lactamase

    OpenAIRE

    Winokur, P. L.; Brueggemann, A.; DeSalvo, D. L.; Hoffmann, L.; Apley, M. D.; Uhlenhopp, E. K.; Pfaller, M A; Doern, G. V.

    2000-01-01

    Salmonella spp. are important food-borne pathogens that are demonstrating increasing antimicrobial resistance rates in isolates obtained from food animals and humans. In this study, 10 multidrug-resistant, cephalosporin-resistant Salmonella isolates from bovine, porcine, and human sources from a single geographic region were identified. All isolates demonstrated resistance to cephamycins and extended-spectrum cephalosporins as well as tetracycline, chloramphenicol, streptomycin, and sulfisoxa...

  19. Plasmid-mediated AmpC β-lactamase (CMY-2) gene in Salmonella typhimurium isolated from diarrheic pigs in South Korea

    OpenAIRE

    Lee, Ki-Eun; Lim, Seong-In; Choi, Hwan-Won; Lim, Suk-Kyung; Song, Jae-Young; An, Dong-Jun

    2014-01-01

    Abstracts Background Salmonella resistant to third-generation cephalosporin has been isolated from an increasing number of animals worldwide. The purpose of this study was to examine ESBL (extended-spectrum β-lactamases)-producing and PABL (plasmid-mediated AmpC β-lactamases)-producing Salmonella isolates from pigs in South Korea. Results Salmonella Typhimurium KVCC-BA1300259 was resistant to ampicillin, amoxicillin/clavulanic acid, cephalothin, chloramphenicol, florfenicol, cefoxithin, genta...

  20. Identification and antimicrobial susceptibility of bacteria isolated from corneal ulcers of dogs Identificação e susceptibilidade antimicrobiana de bactérias isoladas de úlceras de córnea em cães

    OpenAIRE

    M.R. Prado; E.H.S. Brito; M.D. Girão; J.J.C. Sidrim; Rocha, M. F. G.

    2006-01-01

    A total of 22 clinical specimens were obtained from 19 dogs with corneal ulcer (16 unilateral and three bilateral) for isolation and antimicrobial susceptibility evaluation of the isolated bacteria. Bacterial growth was observed in 100% of the samples (n=22). Staphylococcus intermedius was the predominant species (35.5%), followed by Corynebacterium xerosis (19.3%). Gentamicin, ciprofloxacin, chloramphenicol and tobramycin had a high efficacy against all of the isolated bacteria. The results ...

  1. Studies on Aspergillus Flavus Link. Isolated From Maize in Iran

    OpenAIRE

    Houshyar-Fard Mahmoud; Rouhani Hamid; Falahati-Rastegar Mahrokh; Mahdikhani-Moghaddam Esmat; Malekzadeh-Shafaroudi Saeed; Probst Claudia

    2014-01-01

    The Aspergillus flavus population structure from maize kernels was examined. During 2011, samples were collected from two main grain maize production areas in Iran (Fars and Ardebil provinces), shortly before harvest. One-hundred nine A. flavus isolates were recovered on Dichloran Rose Bengal Chloramphenicole (DRBC) agar and Aspergillus flavus/parasiticus medium (AFPA) and grouped into morphotypes and Vegetative Compatibility Groups (VCGs) based on morphological (e.g. sclerotia production), p...

  2. Glutathione and fungal elicitor regulation of a plant defense gene promoter in electroporated protoplasts

    OpenAIRE

    Dron, Michel; Clouse, Steven D.; Dixon, Richard A.; Lawton, Michael A; Lamb, Christopher J.

    1988-01-01

    To investigate the mechanisms underlying activation of plant defenses against microbial attack we have studied elicitor regulation of a chimeric gene comprising the 5′ flanking region of a defense gene encoding the phytoalexin biosynthetic enzyme chalcone synthase fused to a bacterial chloramphenicol acetyltransferase gene. Glutathione or fungal elicitor caused a rapid, marked but transient expression of the chimeric gene electroporated into soybean protoplasts. The response closely resembled...

  3. Activation of human immunodeficiency virus by herpesvirus infection: identification of a region within the long terminal repeat that responds to a trans-acting factor encoded by herpes simplex virus 1.

    OpenAIRE

    Mosca, J D; Bednarik, D P; Raj, N B; Rosen, C A; Sodroski, J G; Haseltine, W A; Hayward, G S; Pitha, P. M.

    1987-01-01

    Herpes simplex virus 1 (HSV-1) infection induces transcription of the chloramphenicol acetyltransferase (CAT) gene directed by the long terminal repeat (LTR) of human immunodeficiency virus (HIV) in both transiently and permanently transfected cells containing the HIV-LTR/CAT hybrid gene. To define the mechanism by which HSV-1 stimulates the HIV LTR, we examined the effects of isolated regulatory genes from HSV-1. The results of cotransfection assays with the immediate-early (IE) genes of HSV...

  4. Antimicrobial susceptibility of Neisseria gonorrhoeae isolates from patients attending a public referral center for sexually transmitted diseases in Belo Horizonte, State of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Ligia Maria Bedeschi Costa

    2013-06-01

    Full Text Available Introduction The aim of this study was to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates obtained from patients attending a public referral center for sexually transmitted diseases and specialized care services (STD/SCS in Belo Horizonte, Brazil. Methods Between March 2011 and February 2012, 201 specimens of Neisseria gonorrhoeae were consecutively obtained from men with symptoms of urethritis and women with symptons of cervicitis or were obtained during their initial consultation. The strains were tested using the disk diffusion method, and the minimum inhibitory concentrations of azithromycin, cefixime, ceftriaxone, ciprofloxacin, chloramphenicol, penicillin, tetracycline and spectinomycin were determined using the E-test. Results The specimens were 100% sensitive to cefixime, ceftriaxone and spectinomycin and exhibited resistances of 4.5% (9/201, 21.4% (43/201, 11.9% (24/201, 22.4% (45/201 and 32.3% (65/201 to azithromycin, ciprofloxacin, chloramphenicol, penicillin and tetracycline, respectively. Intermediate sensitivities of 17.9% (36/201, 4% (8/201, 16.9% (34/201, 71.1% (143/201 and 22.9% (46/201 were observed for azithromycin, ciprofloxacin, chloramphenicol, penicillin and tetracycline, respectively. The specimens had plasmid-mediated resistance to penicillin PPNG 14.5% (29/201 and tetracycline TRNG 11.5% (23/201. Conclusions The high percentage of detected resistance to penicillin, tetracycline, chloramphenicol and ciprofloxacin indicates that these antibiotics are not appropriate for gonorrhea treatment at the Health Clinic and possibly in Belo Horizonte. The resistance and intermediate sensitivity of these isolates indicates that caution is recommended in the use of azithromycin and emphasizes the need to establish mechanisms for the surveillance of antimicrobial resistance for the effective control of gonorrhea.

  5. Isolated Bilateral Trigeminal Neuropathy in Sarcoidosis Presenting with Neurotrophic Corneal Ulcers

    OpenAIRE

    L. Esakowit; M. Gupta; Lascaratos, G.; A. Syrogiannis

    2010-01-01

    Sarcoidosis is a multisystem granulomatous disease that may affect various organs. Nevertheless, involvement of the trigeminal nerve is exceedingly uncommon. This report presents a rare case of isolated bilateral trigeminal neuropathy presenting with neurotrophic corneal ulcers. The patient was treated with topical chloramphenicol and lubricants, as well as botulinum toxin injection to the upper eyelid to induce ptosis. Our case illustrates the importance of recognizing that bilateral corneal...

  6. Protein-DNA interactions in the cAMP responsive promoter region of the murine ornithine decarboxylase gene.

    OpenAIRE

    Palvimo, J J; Eisenberg, L M; Jänne, O A

    1991-01-01

    To evaluate the function of the murine ornithine decarboxylase (ODC) gene promoter, expression of chimeric ODC-chloramphenicol acetyltransferase (CAT) plasmids (pODCcat) containing 1,658 nt of the ODC promoter sequence and its various 5'-deletions was analyzed. In transient expression assays with NIH/3T3 mouse cells, pODCcat constructs exhibited fairly strong promoter activity yielding CAT values up to 40% of those obtained with the viral promoter RSV. Interestingly, 5'-deletions of the pODCc...

  7. Antimicrobial resistance in invasive non-typhoid Salmonella from the Democratic Republic of the Congo : emergence of decreased fluoroquinolone susceptibility and extended-spectrum beta lactamases

    OpenAIRE

    Octavie Lunguya; Veerle Lejon; Marie-France Phoba; Sophie Bertrand; Raymond Vanhoof; Youri Glupczynski; Jan Verhaegen; Jean-Jacques Muyembe-Tamfum; Jan Jacobs

    2013-01-01

    Background: Co-resistance against the first-line antibiotics ampicillin, chloramphenicol and trimethoprim/sulphamethoxazole or multidrug resistance (MDR) is common in non typhoid Salmonella (NTS). Use of alternative antibiotics, such as fluoroquinolones or third generation cephalosporins is threatened by increasing resistance, but remains poorly documented in Central-Africa. Methodology/Principal findings: As part of a microbiological surveillance study in DR Congo, blood cultures were collec...

  8. Determination of Susceptibilities of 26 Leptospira sp. Serovars to 24 Antimicrobial Agents by a Broth Microdilution Technique

    OpenAIRE

    Murray, Clinton K.; Hospenthal, Duane R.

    2004-01-01

    The MICs of 24 antimicrobials for 26 Leptospira spp. serovars were determined using a broth microdilution technique. The MICs at which 90% of isolates tested were inhibited (MIC90s) of cefepime, imipenem-cilastatin, erythromycin, clarithromycin, and telithromycin were all ≤0.01 μg/ml. The MIC90s of amoxicillin, aztreonam, cefdinir, chloramphenicol, and penicillin G were ≥3.13 μg/ml. Many antimicrobials have excellent in vitro activity against Leptospira.

  9. A generic intron increases gene expression in transgenic mice.

    OpenAIRE

    Choi, T; Huang, M; Gorman, C; Jaenisch, R

    1991-01-01

    To investigate the role of splicing in the regulation of gene expression, we have generated transgenic mice carrying the human histone H4 promoter linked to the bacterial gene for chloramphenicol acetyltransferase (CAT), with or without a heterologous intron in the transcription unit. We found that CAT activity is 5- to 300-fold higher when the transgene incorporates a hybrid intron than with an analogous transgene precisely deleted for the intervening sequences. This hybrid intron, consistin...

  10. Release of human immunodeficiency virus by THP-1 cells and human macrophages is regulated by cellular adherence and activation.

    OpenAIRE

    Shattock, R.J.; Friedland, J S; Griffin, G. E.

    1993-01-01

    Macrophage adherence, an important regulatory signal, has the potential to affect human immunodeficiency virus (HIV) production either directly or by priming monocytes to respond to other activating signals. We have investigated the role of adherence as an activator of HIV-1 transcription and release. The effects of adherence on HIV-1 transcription were examined by using THP-1 cells, a human monocytic cell line, transfected with HIV long terminal repeat (LTR)-chloramphenicol acetyltransferase...

  11. Differential effects of human cytomegalovirus on integrated and unintegrated human immunodeficiency virus sequences.

    OpenAIRE

    Koval, V.; Jault, F M; Pal, P G; Moreno, T N; Aiken, C; Trono, D; Spector, S A; Spector, D H

    1995-01-01

    Human cytomegalovirus (HCMV) has been implicated as a potential cofactor in human immunodeficiency virus type 1 (HIV-1)-related disease. Previously, we reported that HCMV inhibits HIV-1 RNA and protein synthesis in cells productively infected with both viruses but, in transient assays, activates an HIV-1 long terminal repeat-chloramphenicol acetyltransferase (LTR-CAT) construct introduced into the cell by transfection (V. Koval, C. Clark, M. Vaishnav, S. A. Spector, and D. H. Spector, J. Viro...

  12. Bacterial Isolation and their antibiogram from non-specific infection in poultry of Marathwada region

    Directory of Open Access Journals (Sweden)

    M.A.Siddiqui

    2008-04-01

    Full Text Available A total of 103 samples of poultry of different age groups of non specific infections were tested. The cultural examination revealed presence of the organisms in descending order E. coli, Staphylococci, Enterobactor, Pseudomonas, Bacillus, Streptococci and Klebsiella. Antibiogram of these samples showed Chloramphenicol, Gentamicin and Ampicillin as most effective antibiotics while Doxycycline, Streptomycin and Oxytetracycline are moderately effective. [Veterinary World 2008; 1(2.000: 52-53

  13. Comparison of Common Antibiotic Therapies for Haemophilus Pleuropneumonia in Pigs

    OpenAIRE

    Willson, Philip J.; Osborne, A. Dudley

    1985-01-01

    Three experiments were done to evaluate some antibiotic therapies that are used commonly to treat pigs infected with Haemophilus pleuropneumoniae. Haemophilus-free piglets, 12 weeks of age, were challenged in a chamber with an aerosol of H. pleuropneumoniae serotype 1 and were medicated with antibiotics at various times before or after challenge. Antibiotic formulations which are commonly used to treat pneumonia in swine were used. They were chloramphenicol, penicillin, and a long-acting form...

  14. A Selective Medium for Quantitative Reisolation of Trichoderma harzianum from Agaricus bisporus Compost

    OpenAIRE

    Williams, Josie; Clarkson, John M.; Mills, Peter R.; Cooper, Richard M

    2003-01-01

    We adapted a selective medium, previously developed for reisolation of Trichoderma spp. from soil, for quantitative determination of growth of T. harzianum from commercial Agaricus bisporus composts. This medium enables comparisons of aggressive (sensu inhibition of A. bisporus yield) with nonaggressive T. harzianum groups. The resulting medium contains the antimicrobials chloramphenicol, streptomycin, quintozene, and propamocarb and was highly selective, allowing the recovery of T. harzianum...

  15. Mechanisms Governing the Selection of Translation Initiation Sites on Foot-and-Mouth Disease Virus RNA ▿

    OpenAIRE

    Pöyry, Tuija A.A.; Jackson, Richard J.

    2011-01-01

    Translation initiation dependent on the foot-and-mouth disease virus (FMDV) internal ribosome entry site (IRES) occurs at two sites (Lab and Lb), 84 nucleotides (nt) apart. In vitro translation of an mRNA comprising the IRES and Lab-Lb intervening segment fused to a chloramphenicol acetyltransferase (CAT) reporter has been used to study the parameters influencing the ratio of the two products and the combined product yield as measures of relative initiation site usage and productive ribosome ...

  16. Vibrio cholerae O139 Multiple-Drug Resistance Mediated by Yersinia pestis pIP1202-Like Conjugative Plasmids▿

    OpenAIRE

    Pan, Jing-Cao; Ye, Rong; Wang, Hao-Qiu; Xiang, Hai-Qing; ZHANG Wei; Yu, Xin-Fen; Meng, Dong-Mei; He, Zhe-Sheng

    2008-01-01

    A conjugative plasmid, pMRV150, which mediated multiple-drug resistance (MDR) to at least six antibiotics, including ampicillin, streptomycin, gentamicin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole, was identified in a Vibrio cholerae O139 isolate from Hangzhou, eastern China, in 2004. According to partial pMRV150 DNA sequences covering 15 backbone regions, the plasmid is most similar to pIP1202, an IncA/C plasmid in an MDR Yersinia pestis isolate from a Madagascar bubon...

  17. Two-Step Solid Lipid Extrusion as a Process to Modify Dissolution Behavior

    OpenAIRE

    Windbergs, Maike; Gueres, Sinan; Strachan, Clare J.; Kleinebudde, Peter

    2010-01-01

    Extrudates based on varying ratios of the triglyceride tripalmitin and the hydrophilic polymer polyethylene glycol as matrix formers were produced as oral dosage forms with controlled release characteristics. The extrudates were processed below the melting points of the excipients and contained the hydrophobic model drug chloramphenicol. The influence of the ratio of the matrix formers on drug dissolution was investigated, with an increase in the water-soluble polymer content increasing the d...

  18. Phenotypical characterization of Candida spp. isolated from crop of parrots (Amazona spp.) Caracterização fenotípica de Candida spp. isoladas de inglúvio de papagaios (Amazona spp.)

    OpenAIRE

    Renata G. Vieira; Selene D. Acqua Coutinho

    2009-01-01

    The purpose of this study was to characterize Candida isolates from crop of parrots. Forty baby parrots of genus Amazona, species aestiva and amazonica that were apprehended from wild animal traffic were used: 18 presented ingluvitis and 22 other alterations, but showing general debilitation. Samples were seeded on Sabouraud dextrose agar with chloramphenicol after be obtained by the introduction of urethral probe through the esophagus. Based on morphology and biochemical reactions (API 20C) ...

  19. Reconstitution of the gastrointestinal microflora of lactobacillus-free mice.

    OpenAIRE

    Tannock, G W; Crichton, C.; Welling, G W; Koopman, J. P.; Midtvedt, T

    1988-01-01

    A colony of mice that do not harbor lactobacilli in their digestive tracts but whose intestinal microflora is otherwise functionally similar to that of conventional animals was derived. Methods used to reconstitute the intestinal microflora of the mice included inoculation of the animals with cultures of specific microbes, noncultivable microbes attached to epithelial cells, and cecal contents from conventional mice treated with chloramphenicol. Twenty-six microflora-associated characteristic...

  20. Targeting of human catalase to peroxisomes is dependent upon a novel COOH-terminal peroxisomal targeting sequence

    OpenAIRE

    1996-01-01

    We have identified a novel peroxisomal targeting sequence (PTS) at the extreme COOH terminus of human catalase. The last four amino acids of this protein (-KANL) are necessary and sufficient to effect targeting to peroxisomes in both human fibroblasts and Saccharomyces cerevisiae, when appended to the COOH terminus of the reporter protein, chloramphenicol acetyl transferase. However, this PTS differs from the extensive family of COOH-terminal PTS tripeptides collectively termed PTS1 in two ma...

  1. Oligonucleotide that binds nuclear factor NF-kappa-B acts as a lymphoid-specific and inducible enhancer element

    OpenAIRE

    Pierce, J. W.; Lenardo, M; Baltimore, D

    1988-01-01

    The immunoglobulin kappa light chain gene contains a lymphoid-specific enhancer that includes several short protein-binding sequences. The sequence that binds the nuclear factor NF-kappa B was tested for its ability to act independently as an enhancer element by inserting it into test plasmids containing the chloramphenicol acetyltransferase gene. When analyzed for activity by transient transfection into lymphoid and nonlymphoid cells, a single copy of the NF-kappa B binding site could act as...

  2. Non-specific seminal tract infection and male infertility : a bacteriological study.

    OpenAIRE

    Mogra N; Dhruva A; Kothari L

    1981-01-01

    70 infertile males with epididymal tenderness, pus cells in the semen, and/or history of urinary tract infection were studied by semen culture examination. Significant growth of Streptococcus fecalis, Escherichia coli, coagulase positive Staphylococci, Proteus valgaris, Pseudomonas pyocyanea, and beta hemolytic Strepticocci was found in 42.9% of the cases. Most of the tested strains were sensitive to ampicillin, cotrimoxazole, nitrofurantoin, erythromycin, and chloramphenicol. In a ...

  3. Streptococcus suis, an Emerging Drug-Resistant Animal and Human Pathogen

    OpenAIRE

    Palmieri, Claudio; Varaldo, Pietro E.; Facinelli, Bruna

    2011-01-01

    Streptococcus suis, a major porcine pathogen, has been receiving growing attention not only for its role in severe and increasingly reported infections in humans, but also for its involvement in drug resistance. Recent studies and the analysis of sequenced genomes have been providing important insights into the S. suis resistome, and have resulted in the identification of resistance determinants for tetracyclines, macrolides, aminoglycosides, chloramphenicol, antifolate drugs, streptothricin,...

  4. Redox Transformations of Arsenic Oxyanions in Periphyton Communities

    OpenAIRE

    Kulp, Thomas R.; Hoeft, Shelley E.; Oremland, Ronald S.

    2004-01-01

    Periphyton (Cladophora sp.) samples from a suburban stream lacking detectable dissolved As were able to reduce added As(V) to As(III) when incubated under anoxic conditions and, conversely, oxidized added As(III) to As(V) with aerobic incubation. Both types of activity were abolished in autoclaved controls, thereby demonstrating its biological nature. The reduction of As(V) was inhibited by chloramphenicol, indicating that it required the synthesis of new protein. Nitrate also inhibited As(V)...

  5. Construction and Use of Derivatives of Transposon Tn4001 That Function in Mycoplasma pulmonis and Mycoplasma arthritidis

    OpenAIRE

    Dybvig, Kevin; French, C. Todd; Voelker, LeRoy L.

    2000-01-01

    Previous attempts to introduce transposon Tn4001 into Mycoplasma pulmonis and Mycoplasma arthritidis have not been successful, possibly due to functional failure of the transposon's gentamicin resistance determinant. Tn4001C and Tn4001T were constructed, respectively, by insertion of a chloramphenicol acetyltransferase gene and the tetM tetracycline resistance determinant into Tn4001. Both Tn4001C and Tn4001T transposed in M. pulmonis, and Tn4001T transposed in M. arthritidis. The incorporati...

  6. Functional interactions within 23S rRNA involving the peptidyltransferase center.

    OpenAIRE

    Douthwaite, S

    1992-01-01

    A molecular genetic approach has been employed to investigate functional interactions within 23S rRNA. Each of the three base substitutions at guanine 2032 has been made. The 2032A mutation confers resistance to the antibiotics chloramphenicol and clindamycin, which interact with the 23S rRNA peptidyltransferase loop. All three base substitutions at position 2032 produce an erythromycin-hypersensitive phenotype. The 2032 substitutions were compared with and combined with a 12-bp deletion muta...

  7. Inhibition of Bacterial Multidrug Resistance by Celecoxib, a Cyclooxygenase-2 Inhibitor▿

    OpenAIRE

    Kalle, Arunasree M.; Rizvi, Arshad

    2010-01-01

    Multidrug resistance (MDR) is a major problem in the treatment of infectious diseases and cancer. Accumulating evidence suggests that the cyclooxygenase-2 (COX-2)-specific inhibitor celecoxib would not only inhibit COX-2 but also help in the reversal of drug resistance in cancers by inhibiting the MDR1 efflux pump. Here, we demonstrate that celecoxib increases the sensitivity of bacteria to the antibiotics ampicillin, kanamycin, chloramphenicol, and ciprofloxacin by accumulating the drugs ins...

  8. Multiple antibiotic resistance in Stenotrophomonas maltophilia.

    OpenAIRE

    Alonso, A.; Martínez, J L

    1997-01-01

    A cryptic multidrug resistance (MDR) system in Stenotrophomonas maltophilia, the expression of which is selectable by tetracycline, is described. Tetracycline resistance was the consequence of active efflux of the antibiotic, and it was associated with resistance to quinolones and chloramphenicol, but not to aminoglycosides or beta-lactam antibiotics. MDR is linked to the expression of an outer membrane protein (OMP54) both in a model system and in multidrug-resistant clinical isolates.

  9. Cloning vector system for Corynebacterium glutamicum.

    OpenAIRE

    Yoshihama, M; Higashiro, K; Rao, E A; Akedo, M; Shanabruch, W G; Follettie, M T; Walker, G C; Sinskey, A J

    1985-01-01

    A protoplast transformation system has been developed for Corynebacterium glutamicum by using a C. glutamicum-Bacillus subtilis chimeric vector. The chimera was constructed by joining a 3.0-kilobase cryptic C. glutamicum plasmid and the B. subtilis plasmid pBD10. The neomycin resistance gene on the chimera, pHY416, was expressed in C. glutamicum, although the chloramphenicol resistance gene was not. The various parameters in the transformation protocol were analyzed separately and optimized. ...

  10. Preferential Utilization of Aromatic Compounds over Glucose by Pseudomonas putida CSV86

    OpenAIRE

    Basu, Aditya; Apte, Shree K.; Phale, Prashant S.

    2006-01-01

    Pseudomonas putida CSV86, a naphthalene-degrading organism, exhibited diauxic growth on aromatic compounds plus glucose, with utilization of aromatics in the first log phase and of glucose in the second log phase. Glucose supplementation did not suppress the activity of degrading enzymes, which were induced upon addition of aromatic compounds. The induction was inhibited by chloramphenicol, suggesting that de novo protein synthesis was essential. Cells showed cometabolism of aromatic compound...

  11. Isolation of drug-resistant Aeromonas hydrophila from aquatic environments.

    OpenAIRE

    McNicol, L A; Aziz, K. M.; Huq, I; Kaper, J B; Lockman, H A; Remmers, E F; Spira, W M; Voll, M. J.; Colwell, R R

    1980-01-01

    Antibiotic-resistant strains of Aeromonas hydrophila have been isolated from the natural environment in the Chesapeake Bay and areas surrounding Dacca and the Matlab region of Bangladesh. The Bangladesh strains carried resistance to chloramphenicol, streptomycin, and tetracycline, and 57% of them had a multiple streptomycin-tetracycline resistance phenotype correlated with the presence of a large plasmid. The Chesapeake Bay strains were resistant to polymyxin B ane tetracycline, but showed ne...

  12. Antibiotic Resistance of Isolated Bacteria from Urban and Hospital Wastewaters in Hamadan City

    OpenAIRE

    Karimi, M; A.M Ebrahimzadeh Namvar; R Shokoohi; M. Hadi; M Solaimany Aminabad

    2011-01-01

    "nBackground and Objectives: widely use of antibiotics as therapy and uncontrolled discharge of them to receiving waters increased the percentages of antibiotic resistant bacteria in various environments which may cause problems in therapy. The aim of this study was to investigate the antibiotic resistance of E. coli, K. pneumoniae and P. aeruginosa bacteria isolated from urban and hospital wastewaters. Nine antibiotics namely Chloramphenicol, Ciprofloxacin, Trimethoprim Sulfamethoxazol, Gent...

  13. ROLE OF A NOVEL TERPENOID AS EFFLUX INHIBITOR IN TARGETING THE EFFLUX PROTEIN (MexA) OF MULTI-DRUG RESISTANT PSEUDOMONAS AERUGINOSA

    OpenAIRE

    R. Jasmine*, B.N. Selvakumar and S. Aishwarya

    2012-01-01

    Pseudomonas aeruginosa, is one among the few drug resistant organisms causing Urinary Tract Infection. Most strains of Pseudomonas aeruginosa are significantly more resistant, even in the absence of R plasmids, to many antimicrobial agents, including β-lactams, tetracycline, chloramphenicol, and fluoroquinolones, than most other gram-negative rods. This broad-range resistance has so far been assumed to be mainly due to the low permeability of the P. aeruginosa outer membrane. Mex-proteins are...

  14. Altered synthetic response of Campylobacter jejuni to cocultivation with human epithelial cells is associated with enhanced internalization.

    OpenAIRE

    Konkel, M E; Cieplak, W

    1992-01-01

    Campylobacter jejuni has been shown to bind to and enter epithelial cells in culture. The interaction of C. jejuni with INT 407 epithelial cells was examined to determine whether bacterial protein synthesis is required for either binding or internalization. Chloramphenicol, a selective inhibitor of bacterial protein synthesis, significantly reduced the internalization, but not binding, of C. jejuni compared with untreated controls as determined by protection from gentamicin. Electrophoretic a...

  15. Multiple mechanisms in serum factor-induced resistance of Haemophilus influenzae type b to antibody.

    OpenAIRE

    Kuratana, M; Hansen, E J; Anderson, P

    1990-01-01

    Incubation of Haemophilus influenzae type b at less than or equal to 10(7) CFU/ml with serum ultrafiltrate induces a phenotypic conversion in which complement-mediated bactericidal activity by somatic antibodies decreases while killing by capsular antibody is unchanged. Conversion had been shown to occur in a capsule-deficient (b-) mutant of strain Eag (thus appearing independent of capsulation), to include an increase in lipopolysaccharide content, and to be inhibited by chloramphenicol or p...

  16. In vitro activity of CI-919 (AT-2266), an oral antipseudomonal compound.

    OpenAIRE

    Chartrand, S A; Scribner, R K; Weber, A.H. (Anushe); Welch, D F; Marks, M I

    1983-01-01

    We tested CI-919 (AT-2266), a nalidixic acid analog, against 555 gram-positive and gram-negative bacteria, using microbroth or agar dilution methods. The activity of CI-919 was compared with those of cephalosporins, tobramycin, ticarcillin, dicloxacillin, rifampin, chloramphenicol, ampicillin, and trimethoprimsulfamethoxazole. The minimal inhibitory concentrations of CI-919 for 90% of isolates were (in micrograms per milliliter): Pseudomonas spp. (including Pseudomonas aeruginosa), 4.0; Enter...

  17. Lack of in vitro efficacy of oral forms of certain cephalosporins, erythromycin, and oxacillin against Pasteurella multocida.

    OpenAIRE

    Goldstein, E J; Citron, D M; Richwald, G A

    1988-01-01

    The in vitro susceptibility of human isolates of Pasteurella multocida to oral antimicrobial agents from our current study and from a review of the literature suggests that dicloxacillin (oxacillin), erythromycin, clindamycin, cephalexin, cefaclor, and cefadroxil should not be used for empiric therapy of animal bite wounds. Agents that were consistently active against P. multocida were penicillin, ampicillin, amoxicillin-clavulanic acid, tetracycline, minocycline, chloramphenicol, trimethopri...

  18. Role of attP in Integrase-Mediated Integration of the Shigella Resistance Locus Pathogenicity Island of Shigella flexneri

    OpenAIRE

    Turner, Sally A.; Luck, Shelley N.; Sakellaris, Harry; Rajakumar, Kumar; Adler, Ben

    2004-01-01

    The Shigella resistance locus (SRL) pathogenicity island (PAI) in Shigella spp. mediates resistance to streptomycin, ampicillin, chloramphenicol, and tetracycline. It can be excised from the chromosome via site-specific recombination mediated by the P4-related int gene. Here, we show that SRL PAI attP is capable of RecA-independent, site-specific, int-mediated integration into two bacterial tRNA attB sites.

  19. Pneumococcal resistance to antibiotics.

    OpenAIRE

    Klugman, K P

    1990-01-01

    The geographic distribution of pneumococci resistant to one or more of the antibiotics penicillin, erythromycin, trimethoprim-sulfamethoxazole, and tetracycline appears to be expanding, and there exist foci of resistance to chloramphenicol and rifampin. Multiply resistant pneumococci are being encountered more commonly and are more often community acquired. Factors associated with infection caused by resistant pneumococci include young age, duration of hospitalization, infection with a pneumo...

  20. Induction of Nitrate-Dependent Fe(II) Oxidation by Fe(II) in Dechloromonas sp. Strain UWNR4 and Acidovorax sp. Strain 2AN

    OpenAIRE

    Chakraborty, Anirban; Picardal, Flynn

    2013-01-01

    We evaluated the inducibility of nitrate-dependent Fe(II)-EDTA oxidation (NDFO) in non-growth, chloramphenicol-amended, resting-cell suspensions of Dechloromonas sp. strain UWNR4 and Acidovorax sp. strain 2AN. Cells previously incubated with Fe(II)-EDTA oxidized ca. 6-fold more Fe(II)-EDTA than cells previously incubated with Fe(III)-EDTA. This is the first report of induction of NDFO by Fe(II).

  1. Study of the Behavior of Some Yersinia enterocolitica Strains Susceptible to Disinfectants and Antibiotics Isolated from Swine

    OpenAIRE

    Ciceronis Cumpanasoiu; Cristian Emil Cumpanasoiu; Emil Tirziu; Radu Valentin Gros; Bianca Cumpanasoiu; Adia Carmen Tirziu

    2011-01-01

    The species from Yersinia genus are widespread in nature, they could be isolated from warm-blooded and cold-bloodedanimals, from foods, water and soil. Among genus species, Yersinia enterocolitica is most frequently isolated fromhuman and animals. The resistance of Yersinia enterocolitica is similar to Yersinia pseudotuberculosis. Moreover, itresists to refrigeration temperature (+4°C). It is susceptible to streptomycin, chloramphenicol, tetracyclines, polymyxin Band colistin sulfate. Also, Y...

  2. MICROFUNGI AND MYCOTOXINS OF GRAPES FROM EASTERN SLOVAK WINE REGION

    OpenAIRE

    Soňa Felšöciová; Ľubomír Rybárik; Dana Tančinová; Zuzana Mašková; Miroslava Kačániová

    2015-01-01

    The current study investigated an endogenous mycobiota of grapes in Eastern wine region, Slovakia and detection a potentially pathogenic isolates to produce selected mycotoxins. Intact berries from four wine grape cultivars were tested. Seven/eight berries superficially sterilized from each samples were placed on a Dichloran Rose Bengal Chloramphenicol agar in a total of 50 and incubated at 25 °C, 5 - 7 days. A total of 582 isolates were obtained that belonged to ten genera: Alternaria, Asper...

  3. Mutation of Salmonella paratyphi A conferring cross-resistance to several groups of antibiotics by decreased permeability and loss of invasiveness.

    OpenAIRE

    Gutmann, L; Billot-Klein, D; Williamson, R.; Goldstein, F W; Mounier, J; Acar, J F; Collatz, E

    1988-01-01

    A spontaneous one-step mutant of Salmonella paratyphi A selected on ampicillin showed cross-resistance to all beta-lactam antibiotics except imipenem and to aminoglycosides, chloramphenicol, tetracycline, trimethoprim, and quinolones. It also grew as small colonies. Examination of the cell envelope of the mutant showed a quantitative decrease in three major outer membrane proteins of 40.6, 39.6 (presumably porins), and 24 kilodaltons and quantitative as well as qualitative modifications in th...

  4. (Electro)Sensing of Phenicol Antibiotics-A Review.

    Science.gov (United States)

    Pilehvar, Sanaz; Gielkens, Kristoffer; Trashin, Stanislav A; Dardenne, Freddy; Blust, Ronny; De Wael, Karolien

    2016-10-25

    The presence of residues from frequent antibiotic use in animal feed can cause serious health risks by contaminating products meant for human consumption such as meat and milk. The present paper gives an overview of the electrochemical methods developed for the detection of phenicol antibiotic residues (chloramphenicol, thiamphenicol, and florfenicol) in different kinds of foodstuffs. Electrochemical sensors based on different biomolecules and nanomaterials are described. The detection limit of various developed methods with their advantages and disadvantages will be highlighted. PMID:25830490

  5. Influence of efflux pump inhibitors on the multidrug resistance of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To evaluate the effect of efflux pump inhibitors (EPIs) on multidrug resistance of Helicobacter pylori (H. pylori).METHODS: H. pylori strains were isolated and cultured on Brucella agar plates with 10% sheep's blood. The multidrug resistant (MDR) H. pylori were obtained with the inducer chloramphenicol by repeated doubling of the concentration until no colony was seen, then the susceptibilities of the MDR strains and their parents to 9 antibiotics were assessed with agar dilution tests. The present stud...

  6. Evaluation of aztreonam in experimental bacterial meningitis and cerebritis.

    OpenAIRE

    Scheld, W. M.; Brodeur, J P; Gratz, J C; Foresman, P; Rodeheaver, G

    1983-01-01

    Aztreonam (SQ 26,776), a new monocyclic beta-lactam agent, was compared with ampicillin, ampicillin plus chloramphenicol, and gentamicin in rabbits with experimental meningitis induced by, respectively, ampicillin-susceptible Haemophilus influenzae, ampicillin-resistant H. influenzae, and Escherichia coli. Aztreonam was also compared with gentamicin in experimentally induced E. coli cerebritis in rats. Doses of the various agents were delivered that produced near-peak concentrations in serum ...

  7. Transfection of beta-casein chimeric gene and hormonal induction of its expression in primary murine mammary epithelial cells.

    OpenAIRE

    Yoshimura, M.; Oka, T

    1990-01-01

    To study the regulatory sequence elements responsible for casein gene expression, we constructed a chimeric gene containing 5.3 kilobases (kb) of the 5'-flanking sequence and 1.6 kb of the 3'-flanking sequence of the mouse beta-casein gene fused to the bacterial chloramphenicol acetyl-transferase (CAT) gene. The chimeric gene was transfected by the calcium phosphate-precipitation procedure into primary mouse mammary epithelial cells prepared from pregnant mice. The transfection procedure had ...

  8. Prolactin and glucocorticoid hormones synergistically induce expression of transfected rat beta-casein gene promoter constructs in a mammary epithelial cell line.

    OpenAIRE

    Doppler, W; Groner, B; Ball, R K

    1989-01-01

    We have detected hormone response elements in the promoter region of the rat beta-casein gene that confer the synergistic action of prolactin and glucocorticoid hormones upon transcription of chimeric gene constructs. A 2800-base-pair (bp) rat beta-casein gene fragment containing 2300 bp of 5' flanking sequence was placed in front of a chloramphenicol acetyltransferase (CAT) reporter gene and stably transfected into the mouse mammary epithelial cell line HC11. Addition of prolactin or dexamet...

  9. An ATF/CREB site is the major regulatory element in the human herpesvirus 6 DNA polymerase promoter.

    OpenAIRE

    Agulnick, A D; Thompson, J R; Ricciardi, R P

    1994-01-01

    Human herpesvirus 6 (HHV-6) is a recently described T-cell pathogen whose medical relevance and molecular biology are just beginning to be addressed. As a first look at the regulation of viral genes, control of the HHV-6 DNA polymerase promoter was examined. Polymerase gene transcription in HHV-6-infected cells was found to initiate from a single site located 115 bases upstream of the translation start codon. A polymerase promoter-chloramphenicol acetyltransferase reporter gene construct fail...

  10. Determination of the presence of 10 antimicrobial residues in mexican pasteurized milk

    OpenAIRE

    Rey Gutiérrez Tolentino; Mario Noa Pérez; Gilberto Díaz González; Salvador Vega y León; Magdalena González López; Guadalupe Prado Flores

    2005-01-01

    Residues of 9 antimicrobial agents approved in México for veterinary use in dairy cattle (sulfathiazole, sulfamerazine, sulfamethazine, sulfachloropyridazine, sulfamonomethoxine, sulfamethoxazole, nitrofurazone, furaltadone, and furazolidone) and non-approved chloramphenicol residues were studied every two weeks in four commercial brands of Mexican pasteurized milk (A, B, C and D) during one year (n=4×24=96). Drug residues were analyzed by high pressure liquid chromatography HPLC with UV dete...

  11. Mycoplasma hominis Meningitis in a 24 Week Premature Neonate: Case Report and Short Literature Review

    OpenAIRE

    Watson, Louise; Pang, Yee Min; Mitchell, Simon; Dodgson, Andrew

    2008-01-01

    Over the last 20-year period there have been fewer than 10 reported cases of Mycoplasma hominis central nervous system infection in either premature or full term infants. The optimum management of M hominis infection in premature infants is still unclear. We report the case of a premature infant with persistent central nervous system infection caused by M hominis treated successfully with intravenous chloramphenicol. Previous reports of M hominis central nervous infection and its management a...

  12. Evidence that ultraviolet light-induced DNA replication death of recA bacteria is prevented by protein synthesis in repair-proficient bacteria

    International Nuclear Information System (INIS)

    The ultraviolet light (UV) survival curve of Escherichia coli WP10 recA trp is almost biphasic, with a greatly reduced shoulder but demonstrating a transition to decreased slope with increasing fluences, indicating the presence in the culture of a low frequency of resistant cells. Treatment of the culture with chloramphenicol before UV exposure brought almost all of the cells to a high degree of UV resistance, by bringing them to the end of their DNA replication cycle. The survival curves of the repair-proficient E. coli Wp2 trp showed a similar pattern with chloramphenicol treatment or tryptophan starvation before UV exposure, but only if protein synthesis after UV exposure, death occurs unless the cells are in the resistant state characteristic of bacteria at the end of their DNA replication cycle. With repair-proficient bacteria treated before UV exposure with chloramphenicol, when protein synthesis is not blocked after UV exposure, a marked expansion of the shoulder occurs because of the function of another resistance-conferring mechanism. This mechanism also depends on the recA+ gene since expansion of the shoulder does not occur in recA bacteria when protein synthesis is inhibited before UV exposure. (author). 11 refs.; 5 figs

  13. Normal Conjunctival Flora as seen in Adult Patients at Kigali University Teaching Hospital

    Directory of Open Access Journals (Sweden)

    Saiba Eugène Semanyenzi

    2013-06-01

    Full Text Available The aim of this study was to assess the pattern of normal ocular bacterial flora isolated from patients attending the Department of ophthalmology at the Kigali University Teaching Hospital and to evaluate their in vitro susceptibility to common antimicrobial agents. From June to October 2011, collection of specimen was performed by rotating a sterile cotton swab on the lower conjunctival sac from the temporal to the medial fornix. Gram stain and culture was performed and antibiotic sensitivity determined in case of bacterial growth. Of the 120 collected samples, 74 (61.6% showed bacterial growth and all were gram positive. 48.6% were Staphylococcus aureus , while 51.4% were Staphylococcus epidermidis . There was high sensitivity of Staphylococcus aureus to chloramphenicol (100%, clindamycine (92%, oxacilline (86.7%, ciprofloxacine (76.7% and norfloxacine (71.9%. However, there was a high resistance of Staphylococcus aureus to penicilline G (11.1% and tetracycline (52.8%. Staphylococcus epidermidis was highly sensitive to chloramphenicol (71.9% and oxacilline (71.1% while it was resistant to erythromycine (28.6%, norfloxacine (35.3% and penicilline G (40.6%. In this study, all of the isolated pathogens were revealed to be gram-positive bacteria. Chloramphenicol, clindamycine and oxacilline showed good activity against normal flora of the ocular surface and should be used in prevention of post-operative end ophtalmitis.

  14. Synthesis and In Vitro Evaluation of New Thiosemicarbazone Derivatives as Potential Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Zafer Asım Kaplancıklı

    2016-01-01

    Full Text Available In an effort to develop potent antimicrobial agents, new thiosemicarbazone derivatives were synthesized via the reaction of 4-[4-(trifluoromethylphenyl]thiosemicarbazide with aromatic aldehydes. The compounds were evaluated for their inhibitory effects on pathogenic bacteria and yeasts using the CLSI broth microdilution method. Microplate Alamar Blue Assay was also carried out to determine the antimycobacterial activities of the compounds against Mycobacterium tuberculosis H37Rv. Among these derivatives, compounds 5 and 11 were more effective against Enterococcus faecalis (ATCC 29212 than chloramphenicol, whereas compounds 1, 2, and 12 and chloramphenicol showed the same level of antibacterial activity against E. faecalis. Moreover, compound 2 and chloramphenicol exhibited the same level of antibacterial activity against Staphylococcus aureus. On the other hand, the most potent anticandidal derivatives were found as compounds 2 and 5. These derivatives and ketoconazole exhibited the same level of antifungal activity against Candida glabrata. According to the Microplate Alamar Blue Assay, the tested compounds showed weak to moderate antitubercular activity.

  15. An analysis of children with typhoid fever admitted in 1991.

    Directory of Open Access Journals (Sweden)

    Deshmukh C

    1994-10-01

    Full Text Available In 28 children, with bacteriologically and/or serologically diagnosed typhoid fever treated at KEM Hospital, Bombay in 1991, initially one of the three recommended drugs (viz. chloramphenicol, amoxycillin or co-trimoxazole was given for 7 days for defervescence to occur. In those who failed to respond, a second trial of therapy with one of the other two drugs was initiated, after omitting the first drug. A second failure of therapy was taken as an indication to use ciprofloxacin singly. Eventually, 18 (64.3% cases responded to chloramphenicol or amoxycillin or co-trimoxazole. Ciprofloxacin was used in 19(35.7% cases. the failure rate of treatment with chloramphenicol was 50%, with amoxycillin 71.4%, with co-trimoxazole 75% and 0% with ciprofloxacin. An analysis of the 28 cases revealed that apart from fever (in 100%, splenomegaly (in 82.1% was the most important clinical pointer to diagnosis, along with absolute eosinopenia (in 71.4%. There were no major complications, except 2 cases with typhoid hepatitis who responded to choramphenicol and co-trimoxazole, respectively. Blood culture grew Salmonella typhi in 7 cases, of which 5 (72% were multidrug resistant S. typhi. There were no characteristic clinical features to identify multi-drug resistant typhoid fever.

  16. [Antibiotic resistance of bacteria to 6 antibiotics in secondary effluents of municipal wastewater treatment plants].

    Science.gov (United States)

    Lu, Sun-Qin; Li, Yi; Huang, Jing-Jing; Wei, Bin; Hu, Hong-Ying

    2011-11-01

    Prevalence of antibiotic-resistant bacteria in wastewater effluents is concerned as an emerging contaminant. To estimate antibiotic resistance in secondary effluents of municipal wastewater treatment plants, antibiotic tolerance of heterotrophic bacteria, proportion of antibiotic-resistant bacteria and hemi-inhibitory concentrations of six antibiotics (penicillin, ampicillin, cefalexin, chloramphenicol, tetracycline and rifampicin) were determined at two wastewater treatment plants (WWTPs) in Beijing. The results showed that proportions of ampicillin-resistant bacteria in WWTP-G and chloramphenicol-resistant bacteria in WWTP-Q were highest to 59% and 44%, respectively. The concentrations of ampicillin-resistant bacteria in the effluents of WWTP-G and WWTP-Q were as high as 4.0 x 10(3) CFU x mL(-1) and 3.5 x 10(4) CFU x mL(-1), respectively; the concentrations of chloramphenicol-resistant bacteria were 4.9 x 10(2) CFU x mL(-1) and 4.6 x 10(4) CFU x mL(-1), respectively. The data also indicated that the hemi-inhibitory concentrations of heterotrophic bacteria to 6 antibiotics were much higher than common concentrations of antibiotics in sewages, which suggested that antibiotic-resistant bacteria could exist over a long period in the effluents with low concentrations of antibiotics. Antibiotic-resistant bacteria could be a potential microbial risk during sewage effluent reuse or emission into environmental waters. PMID:22295644

  17. A preliminary study on effect of radiative degradation on safe quality of honey

    International Nuclear Information System (INIS)

    The honeys such as rape nectar, lotus nectar and camellia nectar, locally produced in Jiangxi province, were treated with 60Co-γ under three gamma irradiative doses of 4, 6 and 8 kGy. The results showed that after radiated with the three doses, the honeys met the national hygienic standards and the requirements of corporate control for there were no detected colonies of bacteria, coliform bacteria, fungus and yeast within the treated honey samples. The sensory parameters of the honey samples, including appearance, color and luster, odor and taste, were not affected and had no significant differences compared with the control. And the physical and chemical nutrimental index values of moisture, acidity, amylase, fructose, glucose, sucrose, etc., were not significantly affected either. The contents of residual chloramphenicol and hydromethyl furaldehyde (HMF) were decreased with the increase of irradiative dose while there was no chloramphenicol detected under the irradiative dose of 8 kGy. This study suggests that irradiation can not only improve the hygienic indexes of honey and also effectively reduce the contents of residual chloramphenicol and HMF in honey, and thus, provide a powerful technical support for the quality and safety issues of bee products. (authors)

  18. Anoxic survival potential of bivalves: (arte)facts.

    Science.gov (United States)

    de Zwaan, Albertus; Babarro, Jose M F; Monari, Marta; Cattani, Otello

    2002-03-01

    The anoxic survival time of the bivalves Chamelea gallina, Cerastoderma edule and Scapharca inaequivalvis from two different ecosystems and differing anoxia tolerances was studied in static (closed) and flow-through systems. The antibiotics chloramphenicol, penicillin and polymyxin were added, and molybdate (specific inhibitor of the process of sulfate reduction). Survival in (near) anoxic seawater of Chamelea was studied in a static system by comparing untreated seawater with autoclaved seawater and untreated clams with clams incubated in well-aerated seawater, containing the broad-spectrum antibiotic chloramphenicol, prior to the anoxic survival test. With untreated clams and natural seawater (median mortality time 2.4 days) a decrease in pH and exponential accumulation of sulfide and ammonium was observed in the anoxic medium, indicating excessive growth of (sulfate reducing) bacteria. In sterilized seawater LT50 (2.1 days) was not significantly different and again considerable amounts of ammonium and sulfide accumulated. However, pre-treatment of clams with chloramphenicol resulted in an increase of LT50 (11.0 days) by approximately fivefold. Accumulation of ammonium and sulfide was retarded, but was finally even stronger than in the medium containing untreated clams. Median mortality times were 2.5 and 2.4 days for Chamelea and 2.7 and 2.9 days for Cerastoderma for static and flow-through incubations, respectively. Addition of chloramphenicol increased strongly survival time in both systems with corresponding values of 11.0 and 16.3 days for Chamelea, and 6.4 and 6.5 days for Cerastoderma. LT50 of Scapharca in anoxic seawater was 14.4 days. Chloramphenicol and penicillin increased median survival time to 28.5 and 28.7 days, respectively, whereas polymyxin displayed no effect (LT50=13.6 days). Molybdate added to artificial sulfate free seawater blocked biotic sulfide formation, but did not improve survival time (LT50=13.7 days). Overall the results indicate

  19. Antimicrobial resistance patterns and prevalence of class 1 and 2 integrons in Shigella flexneri and Shigella sonnei isolated in Uzbekistan

    Directory of Open Access Journals (Sweden)

    Madiyarov Ruslan S

    2010-12-01

    Full Text Available Abstract Background Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with effective antibiotics is recommended for shigellosis, but options become limited due to globally emerging resistance. One of the mechanisms for the development of resistance utilizes integrons. This study described the antibiotic susceptibility and the presence of class 1 and 2 integrons in S. flexneri and S. sonnei isolated in Uzbekistan. Results We studied 31 isolates of S. flexneri and 21 isolates of S. sonnei isolated in Uzbekistan between 1992 and 2007 for the susceptibility or resistance to ampicillin (Am, chloramphenicol (Cl, tetracycline (Te, co-trimoxazole (Sxt, kanamycin (Km, streptomycin (Str, gentamicin (Gm, cefazolin (Czn, cefoperazone (Cpr, cefuroxime (Cur, ceftazidime (Ctz, nalidixic acid (NA and ciprofloxacin (Cip. Am/Str/Cl/Te and Am/Str/Cl/Te/Sxt resistance patterns were found most frequently in S. flexneri. Single isolates were resistant to aminoglycoside, quinolones and cephalosporins. The resistance patterns were different in the two species. Integrons were detected in 93.5% of S. flexneri (29/31 and 81.0% of S. sonnei (17/21 isolates. In addition, 61.3% of S. flexneri (19/31 isolates and 19.0% of S. sonnei (4/21 isolates carried both classes of integrons. In 29.0% of S. flexneri (9/31 isolates, only class 1 integrons were identified. In S. flexneri isolates, the presence of class 1 integrons was associated with resistance to ampicillin and chloramphenicol. Only Class 2 integrons were present in 61.9% of S. sonnei (13/21 isolates. Conclusions Our study documents antibiotic resistance among Shigella spp. in Uzbekistan. Ninety percent of Shigella strains were resistant to previously used antibiotics. Differences among S. flexneri and S. sonnei isolates in patterns of antimicrobial resistance to routinely used shigellosis antibiotics were observed. The majority of S. flexneri were resistant to ampicillin

  20. Prevalence and Antibiogram of Generic Extended-Spectrum β-Lactam-Resistant Enterobacteria in Healthy Pigs

    Directory of Open Access Journals (Sweden)

    Ifeoma Chinyere UGWU

    2015-09-01

    Full Text Available This study was conducted to isolate generic extended-spectrum β-lactam (ESBL-resistant enterobacteria from pigs reared in Enugu State Southeast, Nigeria and determine the antibacterial resistance profile of the isolates. Rectal swabs were collected from 190, randomly selected, apparently healthy pigs. Isolation of ESBL-resistant enterobacteria was done using Mac Conkey agar supplemented with 2 µg/ml of cefotaxime. Phenotypic characterization of the isolates to generic level was done following standard biochemical methods. Phenotypic resistance of the isolates to antibacterial agents was determined using the disc diffusion method. Out of 46 ESBL-resistant enterobacterial isolates, 4 (8.7% were Escherichia coli, 11 (23.9% were Salmonella species, while 31 (67.4% were Klebsiella species. Resistance of the Salmonella isolates was 45.5% to ciprofloxacin, 36.4% to ofloxacin and levofloxacin, 9.1% to norfloxacin, amikacin and gentamicin, 27.3% to streptomycin, 72.7% to chloramphenicol and 90.9% to tetracycline. Resistance of the Klebsiella isolates was 93.5% to ampicillin, 12.9% to ciprofloxacin, 19.4% to ofloxacin and levofloxacin, 9.7% to norfloxacin and streptomycin, 64.5% to chloramphenicol and 38.7% to tetracycline. Resistance of the E. coli isolates was 100% to gentamicin, 75% to ampicillin and streptomycin, 50% to ciprofloxacin, norfloxacin, chloramphenicol and tetracycline, and 25% to ofloxacin, levofloxacin and amikacin. All the isolates were resistant to ceftriaxone, cefotaxime, ceftazidime, cefepime, cefpodoxime, amoxicillin/clavulanic acid and aztreonam. Resistance of the isolates to more than 3 classes of antibacterial agents tested was 54.8% for Klebsiella, 90.9% for Salmonella and 100% for E. coli, respectively. This study has shown that pigs reared in Enugu State Southeast, Nigeria, are colonized by ESBL-resistant Enterobactericeae and are potential reservoirs and disseminators of these organisms.

  1. Antimicrobial Resistance Profiles of Salmonella spp. from Agricultural Environments in Fruit Production Systems.

    Science.gov (United States)

    Gomba, Annancietar; Chidamba, Lizyben; Korsten, Lise

    2016-09-01

    Foodborne disease outbreaks involving fresh produce have increased in recent years. The risk of infection from contaminated food is worsened by the increased prevalence of antibiotic-resistant strains. This study evaluated the prevalence of antibiotic resistance in Salmonella isolates (n = 263) from agricultural production systems through to the final packed product. Salmonella isolates were preliminarily identified by matrix-assisted laser desorption ionization-time-of-flight mass spectroscopy (MALDI-TOF MS) and API 20E and identities confirmed by invA gene polymerase chain reaction. Antimicrobial susceptibility was performed with 15 antimicrobial agents using the Kirby-Bauer disk diffusion test. Of the 263 Salmonella isolates assessed, 59.3% were resistant to one or more antimicrobials. The most frequently detected resistance was against chloramphenicol and kanamycin (46.7%), trimethoprim-sulfamethoxazole (28%), and streptomycin (14%), and the less frequently detected resistance was toward ampicillin (1.14%), amikacin (0.76%), and amoxicillin-clavulanic acid (0.38%). Multiple antimicrobial resistance (MAR) (resistance to ≥3 antibiotics) was found in 48.7% (76/156) isolates. The most common MAR phenotype was to chloramphenicol and trimethoprim/sulfamethoxazole-kanamycin (43.6%). Resistance to chloramphenicol, kanamycin, or trimethoprim/sulfamethoxazole was only observed in MAR phenotypes. All isolates were susceptible to ceftiofur, cefoxitin, ceftriaxone, ciprofloxacin, nalidixic acid, gentamicin, and tetracycline. This study confirms the importance of fresh produce production environments as potential reservoirs and fresh produce as carriers of antibiotic-resistant Salmonella spp. with significant clinical importance. Further studies to evaluate the actual level of health risk from these pathogens should include characterization of the antibiotic resistance determinant genes among the isolates. PMID:27294335

  2. Kinetic study on coagulase formation and growth of 'Staphylococcus aureus': comparative and combined action of antibiotics and gamma radiation

    International Nuclear Information System (INIS)

    Coagulase production is preserved in Staphylococcus aureus cultures although growth was strongly reduced after irradiation with 90,000 rads by a 60Co source. Kinetic studies on the growth and coagulase formation by non-irradiated and irradiated bacteria are reported, using various antibiotics such as chloramphenicol, actinomycin D and mitomycin. Both chloramphenicol (1-50 μg/ml) and actinomycin D (0.05-0.8 μg/ml) added to S. aureus cultures reduce and finally inhibit growth rate and coagulase synthesis proportionally to their concentration in the medium; irradiated and non-irradiated cultures behave similarly to the inhibitory action of those antibiotics. Mitomycin between 0.2-9.6 μg/ml reduces growth, but enzyme production is slightly affected; high levels of coagulase are observed in non-growing cultures. Mitomycin and gamma radiation affecting DNA give similar results: inhibition of growth but not of enzyme formation. Kinetic studies show that coagulase is synthesized during the first five minutes either in irradiated or in non-irradiated cultures. Indication of a de novo synthesis, instead of a mere release of ready-formed enzyme, is given by using chloramphenicol or actinomycin which strongly inhibit coagulase production in irradiated S. aureus. Cultures treated by those antibiotics have their coagulase levels reduced to the same degree, were they irradiated or not; it is assumed that both types of cultures behave similarly, as far as enzyme production is concerned. A massive irradiation dose alone -or mitomycin in high concentrations alone- may suspend bacterial growth although enzyme synthesis continues. A similar result is obtained by combining lower irradiation doses with an appropriate antibiotic. The combined and/or synergistic actions of gamma radiation and antibiotics could successfully differentiate between the two cellular functions: growth and enzyme synthesis

  3. Evaluation of Trimethoprim/Sulfamethoxazole (SXT), Minocycline, Tigecycline, Moxifloxacin, and Ceftazidime Alone and in Combinations for SXT-Susceptible and SXT-Resistant Stenotrophomonas maltophilia by In Vitro Time-Kill Experiments

    Science.gov (United States)

    Cai, Xuejiu; Zhao, Jin; Cui, Junchang

    2016-01-01

    Background The optimal therapy for infections caused by Stenotrophomonas maltophilia (S. maltophilia) has not yet been established. The objective of our study was to evaluate the efficacy of trimethoprim/sulfamethoxazole (SXT), minocycline, tigecycline, moxifloxacin, levofloxacin, ticarcillin-clavulanate, polymyxin E, chloramphenicol, and ceftazidime against clinical isolated S. maltophilia strains by susceptibility testing and carried out time-kill experiments in potential antimicrobials. Methods The agar dilution method was used to test susceptibility of nine candidate antimicrobials, and time-killing experiments were carried out to evaluate the efficacy of SXT, minocycline, tigecycline, moxifloxacin, levofloxacin, and ceftazidime both alone and in combinations at clinically relevant antimicrobial concentrations. Results The susceptibility to SXT, minocycline, tigecycline, moxifloxacin, levofloxacin, ticarcillin-clavulanate, chloramphenicol, polymyxin E, and ceftazidime were 93.8%, 95.0%, 83.8%, 80.0%, 76.3%, 76.3%, 37.5%, 22.5%, and 20.0% against 80 clinical consecutively isolated strains, respectively. Minocycline and tigecycline showed consistent active against 22 SXT-resistant strains. However, resistance rates were high in the remaining antimicrobial agents against SXT-resistant strains. In time-kill experiments, there were no synergisms in most drug combinations in time-kill experiments. SXT plus moxifloxacin displayed synergism when strains with low moxifloxacin MICs. Moxifloxacin plus Minocycline and moxifloxacin plus tigecycline displayed synergism in few strains. No antagonisms were found in these combinations. Overall, compared with single drug, the drug combinations demonstrated lower bacterial concentrations. Some combinations showed bactericidal activity. Conclusions In S. maltophilia infections, susceptibility testing suggests that minocycline and SXT may be considered first-line therapeutic choices while tigecycline, moxifloxacin, levofloxacin

  4. A clinico-bacteriological study of lacrimal regurgitate in cases of chronic dacryocystitis in a referral hospital in Madhya Pradesh

    Directory of Open Access Journals (Sweden)

    Devendra Kumar Shakya

    2015-01-01

    Full Text Available Background: Chronic dacryocystitis is an inflammation of the lacrimal sac which usually occurs because of the obstruction of the nasolacrimal duct. Objective: The primary objective of the study was to know its clinico-bacteriological profile. Materials and Methods: This prospective observational study was carried out over a period of one year to know the current bacterial flora involved in chronic dacryocystitis. All specimens were processed for isolation and identification of bacterial pathogens according to the standard microbiological techniques. The antibiotic susceptibility pattern was done by Kirby-Bauer disc diffusion method according to the Clinical Laboratory Standards Institute guidelines. Results: Among total 100 cases of chronic dacryocystitis, the highest percentage of infections in relation to age was noted in the age group of 50-60 years and the prevalence rate was higher in female patients compared with male. Out of total chronic dacryocystitis cases, 72% cases were found to be culture positive. Among positive culture, gram positive organisms were higher than that of Gram-negative. Staphylococcus epidermidis was the most frequently isolated and Streptococcus pyogenes was least isolated. The highest percentage of positive samples was found in the mucopurulent discharge followed by extensive purulent and clear fluid, respectively. In Gram-positive isolates, chloramphenicol was the most sensitive followed by cefazolin, ciprofloxacin, ofloxacin, cephalexin, vancomycin, gentamycin, and tobramycin, respectively, whereas in Gram-negative isolate, chloramphenicol and nalidixic acid were equally effective followed by ofloxacin, gentamycin, cephalexin, cefazolin and ciprofloxacin, respectively. Conclusion: S. epidermidis was the most frequently isolated bacteria, and chloramphenicol was the most susceptible drug in Gram-positive and Gram-negative bacteria.

  5. RESISTANCE PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGHE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-02-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests.65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics asfeed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials.

  6. ANTIMICROBIAL RESISTANT PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-12-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests. 65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics as feed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials

  7. Antimicrobial susceptibility monitoring of bacterial pathogens isolated from respiratory tract infections in dogs and cats across Europe: ComPath results.

    Science.gov (United States)

    Morrissey, Ian; Moyaert, Hilde; de Jong, Anno; El Garch, Farid; Klein, Ulrich; Ludwig, Carolin; Thiry, Julien; Youala, Myriam

    2016-08-15

    ComPath is a pan-European resistance monitoring programme collecting bacterial pathogens from dogs and cats. We present data for respiratory tract infection (RTI) isolates collected between 2008 and 2010. Antimicrobial minimal inhibitory concentrations (MICs) were determined and susceptibility calculated following Clinical Laboratory Standards Institute (CLSI) standards for veterinary medicine. The main pathogen from dogs was Staphylococcus intermedius Group (49/215, 22.8%) which was >90% susceptible to most antimicrobials (including oxacillin - 93.9%; 3 isolates confirmed mecA-positive) but only 59.2%, 73.5% and 87.8% susceptible to tetracycline, chloramphenicol and penicillin. Bordetella bronchiseptica (48/215, 22.3%), streptococci (36/215, 16.7%), Escherichia coli (24/215, 11.2%) and Pasteurella multocida (23/215, 10.7%) were also found in dog RTI. There are no breakpoints for Bordetella bronchiseptica. Most streptococci were penicillin- chloramphenicol-, ampicillin- and pradofloxacin-susceptible. None were enrofloxacin-resistant but 6 isolates (16.7%) were of intermediate susceptibility. The least active agent against streptococci was tetracycline (47.2% susceptible). For E. coli, 37.5% were ampicillin-susceptible but 83.3% were amoxicillin/clavulanic acid-susceptible. Only chloramphenicol showed susceptibility>90% against E. coli, with 66.7% tetracycline-susceptible and 79.2% to 87.5% susceptibility to enrofloxacin, trimethoprim-sulfamethoxazole or pradofloxacin. P. multocida were susceptible to pradofloxacin (no other breakpoints are available). The main pathogen from cats was P. multocida (82/186, 44.1%), where only pradofloxacin has breakpoints (100% susceptible). Streptococci were also collected from cats (25/186, 13.4%) and were >90% susceptible to all antimicrobials except tetracycline (36% susceptible). Most susceptibility was calculated with human-derived breakpoints and some antimicrobials had no breakpoints. Therefore predictions of clinical utility

  8. Antibiotic Resistance of Escherichia Coli Isolated From Poultry and Poultry Environment of Bangladesh

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    Muhammad A. Akond

    2009-01-01

    Full Text Available Problem statement: Increased emergence in microbial resistance to antibiotics is a growing problem in Bangladesh, a tropical country with a large agrarian population having limited medical facilities. Wide spread use of antimicrobials in poultry farming here is a concern of multi-drug microbial resistance development that can potentially be transmitted to human pathogens even from non-pathogenic carrier strains. Attempt was made to assess drug susceptibility in Escherichia coli from poultry sources of Bangladesh. Approach: Eighty selected strains isolated from poultry sources were thoroughly characterized by standard cultural and biochemical tests followed by final identification using latex agglutination test of polyvalent anti-sera, from which 50 were tested for susceptibility to 13 antibiotics following disk diffusion method. Results: 145 (58%, out of total 250, were found positive for E. coli. 52-88% of tested E. coli strains from poultry sources were found resistant to Penicillin, Ciprofloxacin, Riphampicin, Kanamycin, Streptomycin, Cefixine, Erythromycin, Ampicillin, Tetracycline, and 20% strains showed resistance to both Chloramphenicol and Neomycin. No strains showed resistance to Norfloxacin and Gentamicin. Sensitivity was recorded in case of 60-86% strains to Norfloxacin, Gentamicin, Chloramphenicol, and Neomycin; and 26-36% strains against Tetracycline, Streptomycin, and Ampicillin. Intermediate resistance/ susceptibility to various antibiotics were observed for 12-36% Escherichia coli strains. Both, resistance and susceptibility were exhibited against Chloramphenicol, Ampicillin, Gentamicin, Neomycin, Tetracycline, Streptomycin and Norfloxacin. Multi drug resistance was found in case of 6-10 antibiotics for all strains tested. Conclusion: Further study is required on the role of poultry borne bacteria as vectors in transmitting drug resistance. Attention is to be paid for personnel hygiene in processing and handling of poultry and

  9. Degradation and de novo synthesis of D1 protein and psbA transcript in reinhardtii during UV-B inactivation of photosynthesis

    Indian Academy of Sciences (India)

    Ratnesh Haturvedi; Adhey Hyam

    2000-03-01

    UV-B induces intensity and time dependent inhibition of photosynthetic O evolution and PS II electron transport Chlamydomonas reinhardtii chloroplast membranes are rapidly and essential for the repair of damaged PS II as chloramphenicol accelerated UV-B inactivation of photosynthesis and psb for the D1 protein. Cells showing 72% inhibition of PS II protein. This shows that synthesis of D1 protein is not the only component involved in the recovery process. Our events, which in turn may limit the repair of damaged PS II.

  10. Matrix effect on the analysis of amphenicols in fish by liquid chromatography-tandem mass spectrometry (LC-MS/MS)

    Science.gov (United States)

    Guidi, L. R.; Tette, P. A. S.; Evangelista, W. P.; Fernandes, C.; Glória, M. B. A.

    2015-01-01

    Matrix effect is an important parameter to be investigated during the development and validation of a method for the quantitative determination of contaminants in food. The objective of this study was to evaluate the matrix effect, through statistical tests, in the quantification of amphenicols in fish by HPLC-MS/MS. The study was performed by comparing the standard curves prepared in solvent solutions and in a fish sample previously known to be free of amphenicols. Since matrix effect was observed for the three analytes, calibration curves for quantification of chloramphenicol, thiamphenicol and florfenicol should be constructed using the matrix.

  11. Disease: H00308 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available io vulnificus [GN:vvu vvy] pore-forming toxin [KO:K10948 K10953] membrane-dama...H00308 Vibrio vulnificus infection Vibrio vulnificus is a gram-negative bacillus fo...oxacin [DR:D08237] Levofloxacin [DR:D08120] Trimethoprim-sulfamethoxazole [DR:D00285] Chloramphenicol [DR:D0...D:21177133 (description, env_factor, drug) Horseman MA, Surani S A comprehensive review of Vibrio vulnificus... PMID:17853628 (description, env_factor) Bross MH, Soch K, Morales R, Mitchell RB Vibrio vulnificus infection: diagnosis and treatment. Am Fam Physician 76:539-44 (2007) ...

  12. Transcriptional activation of homologous viral long terminal repeats by the human immunodeficiency virus type 1 or the human T-cell leukemia virus type I tat proteins occurs in the absence of de novo protein synthesis.

    OpenAIRE

    Jeang, K T; Shank, P R; Kumar, A

    1988-01-01

    The genomes of human retroviruses [human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus (HTLV-I)] encode positive trans-activator proteins, named tat. In the presence of tat, the transcriptional activity of the homologous HIV-1 or HTLV-I long terminal repeat (LTR) promoter is markedly increased. We have constructed mammalian cell lines that contain stably integrated copies of a HIV-1 or a HTLV-I LTR-chloramphenicol acetyltransferase (CAT) gene. When presynthesized HIV-1...

  13. In vivo DNA cloning and adjacent gene fusing with a mini-Mu-lac bacteriophage containing a plasmid replicon.

    OpenAIRE

    Groisman, E A; Castilho, B A; Casadaban, M J

    1984-01-01

    A mini-Mu bacteriophage containing a high copy number plasmid replicon was constructed to clone genes in vivo. A chloramphenicol resistance gene for independent selection and the lacZYA operon to form gene fusions were also incorporated into this phage. This mini-Mu element can transpose at a high frequency when derepressed, and it can be complemented by a helper Mu prophage for lytic growth. DNA sequences that are flanked by two copies of this mini-Mu can be packaged along with them. After i...

  14. Mutational Analysis of the Influenza Virus cRNA Promoter and Identification of Nucleotides Critical for Replication

    OpenAIRE

    Crow, Mandy; Deng, Tao; Addley, Mark; Brownlee, George G.

    2004-01-01

    Replication of the influenza A virus virion RNA (vRNA) requires the synthesis of full-length cRNA, which in turn is used as a template for the synthesis of more vRNA. A “corkscrew” secondary-structure model of the cRNA promoter has been proposed recently. However the data in support of that model were indirect, since they were derived from measurement, by use of a chloramphenicol acetyltransferase (CAT) reporter in 293T cells, of mRNA levels from a modified cRNA promoter rather than the authe...

  15. Identification of a cold shock transcriptional enhancer of the Escherichia coli gene encoding nucleoid protein H-NS.

    OpenAIRE

    La Teana, A; Brandi, A; M. Falconi; Spurio, R; Pon, C. L.; Gualerzi, C O

    1991-01-01

    The hns (27 min) gene encoding the 15.4-kDa nucleoid protein H-NS was shown to belong to the cold shock regulon of Escherichia coli, its expression being enhanced 3- to 4-fold during the growth lag that follows a shift from 37 degrees C to 10 degrees C. A 110-base-pair (bp) DNA fragment containing the promoter of hns fused to a promoterless cat gene (hns-cat fusion) conferred a similar cold shock response to the expression of chloramphenicol acetyltransferase (CAT) activity in vivo and in cou...

  16. Oxidation of long-chain alkanes by Acetobacter rancens

    International Nuclear Information System (INIS)

    The degradation of hexadecane and tetradecane by Acetobacter rancens CCM 1774 was investigated. It was found that this strain is able to grow to a limited extent on hexadecane as a carbon source. The occurrence of n-alkanoic acids and alcohols among the reaction products of growing as well as resting cells indicates a monoterminal degradation of long-chain alkanes. Both alkane-grown and glucose-grown resting cells exhibited alkane oxidizing activities which were not influenced by chloramphenicol. This suggested a constitutive nature of the appropriate enzymes. (orig.)

  17. Activation of an enhancerless gene by chromosomal integration.

    OpenAIRE

    Hamada, H

    1986-01-01

    Expression of enhancerless (E-) and enhancer-containing (E+) genes that are chromosomally integrated was examined. An E- plasmid (pE-cat) containing a chloramphenicol acetyltransferase (cat) gene linked to the simian virus 40 (SV40) early promoter or its E+ counterpart plasmid (pE+-cat) containing the SV40 enhancer was cotransfected into thymidine kinase (TK)-deficient L cells with a cloned tk gene. A number of TK+ transformants were isolated, and expression of the cointegrated cat gene in th...

  18. Matrix effect on the analysis of amphenicols in fish by liquid chromatography-tandem mass spectrometry (LC-MS/MS)

    International Nuclear Information System (INIS)

    Matrix effect is an important parameter to be investigated during the development and validation of a method for the quantitative determination of contaminants in food. The objective of this study was to evaluate the matrix effect, through statistical tests, in the quantification of amphenicols in fish by HPLC-MS/MS. The study was performed by comparing the standard curves prepared in solvent solutions and in a fish sample previously known to be free of amphenicols. Since matrix effect was observed for the three analytes, calibration curves for quantification of chloramphenicol, thiamphenicol and florfenicol should be constructed using the matrix

  19. Simian virus 40 promoters direct expression of the tetracycline gene in plasmid pACYC184.

    OpenAIRE

    Jenkins, F J; Howett, M K; Rapp, F

    1983-01-01

    Insertion of HindIII DNA fragments into the HindIII site of plasmid pACYC184 destroys the promoter of the plasmid tetracycline resistance gene and causes Escherichia coli cells harboring recombinant plasmids to be tetracycline sensitive and chloramphenicol resistant. The HindIII-C DNA fragment of simian virus 40 contains the two virus promoters and the virus origin of replication. We report the isolation of recombinant plasmids that contained the simian virus 40 HindIII-C DNA fragment at the ...

  20. Analysis of p53 mutants for transcriptional activity.

    OpenAIRE

    Raycroft, L.; Schmidt, J. R.; Yoas, K; Hao, M M; Lozano, G.

    1991-01-01

    The wild-type p53 protein functions to suppress transformation, but numerous mutant p53 proteins are transformation competent. To examine the role of p53 as a transcription factor, we made fusion proteins containing human or mouse p53 sequences fused to the DNA binding domain of a known transcription factor, GAL4. Human and mouse wild-type p53/GAL4 specifically transactivated expression of a chloramphenicol acetyltransferase reporter in HeLa, CHO, and NIH 3T3 cells. Several mutant p53 protein...

  1. Catalase-negative Staphylococcus aureus isolated from a diabetic foot ulcer

    Directory of Open Access Journals (Sweden)

    MR Zali

    2010-12-01

    Full Text Available We report a catalase-negative Staphylococcus aureus isolated from a 56-year-old male diabetic patient with foot ulcer who attended our surgery ward. Species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc and fem genes. Antibiotic susceptibility showed that the strain was sensitive to imepenem, chloramphenicol, amoxicillin, vancomycin and resistant to oxacillin, penicillin, ceftriaxone, erythromycin, clindamycin, and amikacin. Clinicians and microbiologists must be encouraged to identify and report these atypical strains and the infections associated with them in order to establish their role in pathogenesis.

  2. The availability and cost of antibiotics for treating PID in the Central Region of Ghana and implications for compliance with national treatment guidelines.

    Science.gov (United States)

    Bosu, W K; Mabey, D

    1998-09-01

    The availability and cost of antibiotics for treating pelvic inflammatory disease (PID) were assessed in 17 drug-dispensing outlets in 5 districts of the Central Region, Ghana. The outlets included the dispensaries of 2 regional and 4 district hospitals, 4 privately-owned pharmacies and 7 chemical seller shops. The most common antibiotics available, including co-trimoxazole, metronidazole, benzylpenicillin, amoxycillin, chloramphenicol and gentamicin, were also the lowest-priced drugs. Conversely, the most expensive antibiotics including ceftriaxone, ciprofloxacin, cefuroxime and spectinomycin, were also the least commonly available. Recommended anti-gonococcal antibiotics (ciprofloxacin, ceftriaxone) may not be prescribed if they are not available in the districts. PMID:9764942

  3. Hsc66, an Hsp70 homolog in Escherichia coli, is induced by cold shock but not by heat shock.

    OpenAIRE

    Lelivelt, M J; Kawula, T H

    1995-01-01

    Hsc66 is the second identified Hsp70 protein in Escherichia coli. Mutations in hscA, the gene encoding Hsc66, compensate for some phenotypic effects of a mutation in hns, a gene encoding the cold-inducible, nucleoid-associated protein H-NS. Expression of hscA was not induced upon heat shock but was induced approximately 11-fold 3 h after a shift from 37 to 10 degrees C. Furthermore, hscA was induced upon chloramphenicol addition, which induces the synthesis of other cold-inducible genes. Mapp...

  4. Occurrence of integrons and antimicrobial resistance genes among Salmonella enterica from Brazil

    DEFF Research Database (Denmark)

    Peirano, G.; Agersø, Yvonne; Aarestrup, Frank Møller;

    2006-01-01

    . The genetic location of class 1 integrons was determined in 25 isolates by hybridization and plasmid transfer experiments. Results: Fifty-five of the isolates were positive for class I integrons. Integron-positive isolates represented 17 different serovars and were mainly from human (n = 28) and....... Sulphonamide resistance was primarily mediated by sul2 and sul3, tetracycline resistance by tet(B) and tet(A), chloramphenicol resistance by catA1, streptomycin resistance by strA and ampicillin resistance by bla(TEM). bla(CTX) and bla(CMY-2) were found in cephalosporin-resistant isolates. Mating and...

  5. Heme regulates the expression in Saccharomyces cerevisiae of chimaeric genes containing 5'-flanking soybean leghemoglobin sequences

    DEFF Research Database (Denmark)

    Jensen, E O; Marcker, K A; Villadsen, IS

    1986-01-01

    The TM1 yeast mutant was transformed with a 2 micron-derived plasmid (YEp24) which carries a chimaeric gene containing the Escherichia coli chloramphenicol acetyl transferase (CAT) gene fused to the 5'- and 3'-flanking regions of the soybean leghemoglobin (Lb) c3 gene. Expression of the chimaeric...... CAT gene is controlled specifically by heme at a post-transcriptional level, most likely by regulating the efficiencies of translation. Expression of another chimaeric gene consisting of the neomycin phosphotransferase (NPTII) gene fused to only the 5'-flanking region of the Lbc3 gene is regulated by...

  6. Transferring Gus gene into intact rice cells by low energy ion beam

    Science.gov (United States)

    Zengliang, Yu; Jianbo, Yang; Yuejin, Wu; Beijiu, Cheng; Jianjun, He; Yuping, Huo

    1993-06-01

    A new technique of transferring genes by low energy ion beam has been reported in this paper. The Gus and CAT (chloramphenicol acetyltransferase) genes, as "foreign" genetic materials, were introduced into the suspension cells and ripe embryos or rice by implantation of 20-30 keV Ar + at doses ranging from 1 × 10 15 to 4 × 10 15 ions/cm 2. The activities of CAT and Gus were detected in the cells and embryos after several weeks. The results indicate that the transfer was a success.

  7. SUSCEPTIBILITY OF 686 STRAINS OF BETA-HEMOLYTIC STREPTOCOCCI ISOLATED FROM CASES OF PHARYNGITIS TO FIVE ANTIBIOTICS IN VITRO

    Directory of Open Access Journals (Sweden)

    R. A. Gharagozloo

    1974-09-01

    Full Text Available This study was undertaken to determine the antibiotic sensitivity of 686 strains of hemolytic streptococci isolated at the School of Public Health, Divi­sion of Streptococcal Studies, to five antibiotics in vitro. All of the strains were sensitive to penicillin, erythromycin, chloramphenicol and ampicillin. 27 (4% of the strains, were resistant to tetracyclin. The clinical implications of this study, particularly in the light of information from other areas, emphasize the fact that, if the blind treatment of acute upper respiratory tract infection with tetracycline were ever justified it has certainly ceased to be so.

  8. Effects of antibiotics and ultraviolet radiation on the halophilic blue-green alga

    International Nuclear Information System (INIS)

    The effects of a variety of antibiotics, ultraviolet radiation and N-methyl-N-nitro-N-nitro-N-nitrosoguanidine (NTG) on the survival and mutability of the halophilic blue-green alga, Aphanothece halophytica, were determined. The halophile was found extremely sensitive to penicillin G and bacitracin; moderately sensitive to novobiocin, amino acid analogs, chloramphenicol and streptomycin; and tolerant to actidione and hydroxyurea. Ultraviolet and NTG killing curves and photoreactivation capabilities were seimilar to those reported for other members of the Chroococcales. Three stable morphological mutants were obtained by ultraviolet and NTG treatment, the latter being much more efficient in the production of mutants. (orig.)

  9. Researches and commercialization of food irradiation technology in China

    International Nuclear Information System (INIS)

    The status of food irradiation on research, standard and commercialization is described in the paper. The main research fields now include degradation of chloramphenicol residue by irradiation, promoting safety of meat products, frozen seafood and ready-to-eat products by irradiation, lower activity of allergic protein by irradiation, identification of irradiated food and irradiation as a phytosanitary treatment. The existed standards need to be revised, and new standard need to be established. The commercialization stages of food irradiation and quality assurance system of irradiation company are also analyzed. (authors)

  10. Effect of Phenobarbital on Chloramphonicol-Induced Toxicity in Rat Liver and Small Intestine

    OpenAIRE

    Massumeh Ahmadizadeh; Masood Esmailpoor; Zahra Goodarzi

    2013-01-01

      Objective(s): The aim of the present study is to determine the effect of Chloramphenicol (CAP) on rat liver and small intestine. Effect of phenobarbital (PB) on CAP toxicity was also investigated.   Materials and Methods:   Rats were received CAP at doses of 0, 200, 400 and 600 mg/kg. Another group was pretreated with 80 mg/kg PB 30 min prior to administration of various doses of CAP. The experiment was repeated for seven consecutive days. Blood was collected for det...

  11. Promoter and 11-kilobase upstream enhancer elements responsible for hepatoma cell-specific expression of the rat ornithine transcarbamylase gene.

    OpenAIRE

    Murakami, T.; Nishiyori, A; Takiguchi, M.; Mori, M

    1990-01-01

    The gene for ornithine transcarbamylase (OTC; EC 2.1.3.3), a urea cycle enzyme, is expressed almost exclusively in the liver and small intestine. To identify DNA elements regulating transcription of the OTC gene in the liver, transient expression analysis was carried out by using hepatoma (HepG2) and nonhepatic (CHO) cell lines. The 1.3-kilobase 5'-flanking region of the rat OTC gene directed expression of the fused chloramphenicol acetyltransferase gene in HepG2 cells much more efficiently t...

  12. Characterization of a transcriptional promoter of human papillomavirus 18 and modulation of its expression by simian virus 40 and adenovirus early antigens

    International Nuclear Information System (INIS)

    RNA present in cells derived from cervical carcinoma that contained human papillomavirus 18 genomes was initiated in the 1.053-kilobase BamHI fragment that covered the complete noncoding region of this virus. When cloned upstream of the chloramphenicol acetyltransferase gene, this viral fragment directed the expression of the bacterial enzyme only in the sense orientation. Initiation sites were mapped around the ATG of open reading frame E6. This promoter was active in some human and simian cell lines, and its expression was modulated positively by simian virus 40 large T antigen and negatively by adenovirus type 5 E1a antigen

  13. Rapid Consumption of Low Concentrations of Methyl Bromide by Soil Bacteria

    OpenAIRE

    Hines, Mark E.; Crill, Patrick M; Varner, Ruth K.; Talbot, Robert W; Shorter, Joanne H.; Kolb, Charles E.; Harriss, Robert C.

    1998-01-01

    A dynamic dilution system for producing low mixing ratios of methyl bromide (MeBr) and a sensitive analytical technique were used to study the uptake of MeBr by various soils. MeBr was removed within minutes from vials incubated with soils and ∼10 parts per billion by volume of MeBr. Killed controls did not consume MeBr, and a mixture of the broad-spectrum antibiotics chloramphenicol and tetracycline inhibited MeBr uptake by 98%, indicating that all of the uptake of MeBr was biological and by...

  14. Extended Spectrum Beta Lactamase producing Cephalosporin resistant Salmonella Typhi, reported from Rawalpindi, Pakistan.

    Science.gov (United States)

    Munir, Tehmina; Lodhi, Munir; Ansari, Jawad Khaliq; Andleeb, Saadia; Ahmed, Mushtaq

    2016-08-01

    Typhoid is endemic in many parts of southeast Asia. Due to the resistance of the organism to first line of antibiotics (ampicillin, chloramphenicol, cotrimoxazole) as well as to fluoroquinolones, third generation cephalosporins have been in use for the empiric treatment of typhoid for years. However an increasing incidence of Salmonella Typhi is being reported sporadically from various regions. We report a case of typhoid due to Salmonella Typhi which was non-responsive to treatment with a cephalosporin, was found to be multidrug resistant and resistant to ciprofloxacin and third generation cephalosporin as well. The patient was finally treated successfully with intravenous administration of a carbapenem. PMID:27524545

  15. Antimicrobial resistance among Campylobacter jejuni isolated from raw poultry meat at retail level in Denmark

    DEFF Research Database (Denmark)

    Andersen, S. R.; Saadbye, P.; Shukri, Naseer Mahmoud;

    2006-01-01

    was observed for chloramphenicol, nalidixic acid and ciprofloxacin (P <0.05). The trends in resistance in the period 1996-2003 among C jejuni isolates from chicken meat indicate a decrease in the occurrence of resistance towards fluoroquinolones. This may be due to reduced application of...... fluoroquinolones for food animals. Monitoring of the occurrence of antimicrobial resistance in C. jejuni isolated from raw uncooked poultry has been performed on a yearly basis since 1996, thus providing useful insight into consumer exposure to antimicrobial-resistant C. jejuni....

  16. Cholangiohepatitis in a dog.

    Science.gov (United States)

    Forrester, S D; Rogers, K S; Relford, R L

    1992-06-01

    Cholangiohepatitis was diagnosed in a dog with a 4-day history of anorexia, vomiting, fever, and icterus. Additional findings included signs of depression, dehydration, hepatosplenomegaly, and abdominal discomfort. Exploratory laparotomy was performed, and specimens of liver, spleen, and bile were obtained. Histologic evaluation of liver and spleen revealed acute, suppurative cholangio-hepatitis and splenitis, respectively. Cultures of liver and bile yielded Klebsiella sp. The dog responded to rehydration and intravenous administration of chloramphenicol. Although uncommon, cholangiohepatitis should be suspected in dogs with anorexia, fever, vomiting, icterus, and signs of abdominal discomfort. Definitive diagnosis requires bacterial cultures of liver and bile. Administration of an appropriate antibiotic should resolve clinical signs. PMID:1624352

  17. Comparison of the transcriptional activity of the long terminal repeats of simian immunodeficiency viruses SIVmac251 and SIVmac239 in T-cell lines and macrophage cell lines.

    OpenAIRE

    Anderson, M G; Clements, J E

    1991-01-01

    The U3 regions of the long terminal repeats (LTRs) of simian immunodeficiency viruses SIVmac251 and SIVmac239 were analyzed for basal transcriptional activity and for interaction with cellular factors in the T-cell line HUT-78 and the monocyte/macrophage cell line U937. A number of 5' deletions and mutations were made in the U3 regions of the two LTRs, and these constructs were placed upstream of a plasmid containing the bacterial chloramphenicol acetyltransferase reporter gene. The nucleotid...

  18. MDM2 Suppresses p73 Function without Promoting p73 Degradation

    OpenAIRE

    Zeng, Xiaoya; Chen, Lihong; Jost, Christine A.; Maya, Ruth; Keller, David; Wang, Xinjiang; Kaelin, William G.; Oren, Moshe; Chen, Jiandong; Lu, Hua

    1999-01-01

    The newly identified p53 homolog p73 can mimic the transcriptional activation function of p53. We investigated whether p73, like p53, participates in an autoregulatory feedback loop with MDM2. p73 bound to MDM2 both in vivo and in vitro. Wild-type but not mutant MDM2, expressed in human p53 null osteosarcoma Saos-2 cells, inhibited p73- and p53-dependent transcription driven by the MDM2 promoter-derived p53RE motif as measured in transient-transfection and chloramphenicol acetyltransferase as...

  19. TERMINALIA CHEBULA: A TREATMENT AGAINST PATHOGENIC PROTEUS VULGARIS STRAINS ASSOCIATED WITH URINARY TRACT INFECTION

    OpenAIRE

    Tariq A.L.; Reyaz. A. L

    2013-01-01

    Terminalia chebula was used to find out the new sort of treatment for the urinary tract infections caused by Proteus vulgaris. The causative agent was identified as Proteus vulgaris by staining and biochemical methods. It is responsible to cause urinary tract infection and most of strains show the resistance against the broad spectrum antibiotics: Ceftazidime (30μg), Ofloxacin (50μg), Norfloxacin (30μg), Tetracycline (30μg), Ampicillin (30μg), Chloramphenicol (25μg) and Gentamycin (20μg). The...

  20. Sodium dodecyl sulfate-sensitive septation in a mitomycin C-sensitive, mtc, mutant of Escherichia coli.

    OpenAIRE

    Higashi, T; K. Suzuki; Otsuji, N

    1981-01-01

    A mitomycin C-sensitive, mtc, mutant of Escherichia coli has an altered cell surface and is sensitive to sodium dodecyl sulfate (SDS). The mutant, M27, formed multinucleate nonseptated filaments in the presence of a low concentration of SDS (50 microgram/ml). When the culture grown at that concentration of SDS was diluted with an SDS-free medium, the filaments began to divide at a very rapid rate after a lag of about 20 min. Chloramphenicol inhibited this recovery division when added within 1...

  1. SUPRESSION OF MICROSOMAL OXIDATION WEAKENS HISTOCHROME’S DIURETIC EFFECT AT RATS

    Directory of Open Access Journals (Sweden)

    O. S. Talalaeva

    2016-01-01

    Full Text Available Histochrome is the medicinal form of echinochrome (2, 3, 5, 6, 8-pentahydroxy-7-ethyl-1,4-naphthoquinone. Arisen during clinical application of the drug questions concerning its biotransformation have predetermined the aim of this research: to study participation liver monooxygenase system in maintenance of histochrome’s pharmacological activity.Simple and informative method of the lifetime control of liver monooxygenase systems influence on a metabolism of a medical product is the estimation of changes of pharmacological effect of a r esearched preparation on a background microsomal oxidations i nhibitor. In experiments on rats chloramphenicol action on diuretic effect of histochrome, as the most convenient for screening, was i nvestigated.To control group of animals during 10 days were hypodermically entered by histochrome in a doze of 10 mg/kg (n = 15. Experimental animals preliminary oral received 50 mg/kg of chloramphenicol before three hours of histochrome introduction (n = 16. In both groups of animals measured volume daily excretion of water, creathinin, sodium and potassium ions excretions in experimental rats each two days. The initial level of parameters of excretory kidneys functions were estimated before introduction of preparations at animals.Long-term histochrome’s injection was followed by a fivefold increasing of water excretion and simultaneously creathinin growth one. Allocation of ions of sodium was statistically significantly increased by 11-th day of experiment, and potassium ions – since the ninth day of histochrome injection. In conditions preliminary chloramphenicol applications volume daily daily urine output and creathinin excretion were essentially less control parameters. Allocation with urine of ions of sodium was decreased almost twice in comparison with the values, fixed at introduction histochrome. Excretion potassium ions ware corresponded to an initial level during all period of supervision.Taking into

  2. Rickettsial infection of the central nervous system: the role of prompt antimicrobial therapy.

    Science.gov (United States)

    Shaked, Y

    1991-04-01

    Rickettsial diseases of man, which are prevalent in all the continents (except Antartica) continue to be a major health problem in tropical and temperate parts of the world. Rickettsioses must be considered in every traveller seeking medical attention soon after returning from endemic areas, since the disease can be associated with significant morbidity. When a definite diagnosis has been made by specific serological tests, prompt antimicrobial therapy is indicated. A tetracycline should be regarded as the drug of choice due to its high efficacy, low toxicity, superior in vitro activity and the possibility of relapse which can follow chloramphenicol therapy. PMID:1852855

  3. Phenotyping of Salmonella serotypes isolated from natural sources of water in rural areas of East Sikkim.

    Science.gov (United States)

    Poonia, S; Singh, T S; Tsering, D C

    2015-01-01

    The objective of the study was to conduct bacteriological analysis of water with special reference to Salmonella spp from natural sources of rural habitations of East Sikkim. A total of 28 Salmonella serovars isolated were biotyped, phage typed and tested for their anti-microbial susceptibility. All the isolates of Salmonella enterica serovar Typhi belonged to Biotype I. Four isolates of S. typhi belonged to phage type A. All S. paratyphi A isolates belong to phage 2. All the isolates were sensitive to chloramphenicol, cefixime and amikacin. Untreated natural water sources are unsafe for human consumption. PMID:25560018

  4. Phenotyping of Salmonella serotypes isolated from natural sources of water in rural areas of East Sikkim

    Directory of Open Access Journals (Sweden)

    S Poonia

    2015-01-01

    Full Text Available The objective of the study was to conduct bacteriological analysis of water with special reference to Salmonella spp from natural sources of rural habitations of East Sikkim. A total of 28 Salmonella serovars isolated were biotyped, phage typed and tested for their anti-microbial susceptibility. All the isolates of Salmonella enterica serovar Typhi belonged to Biotype I. Four isolates of S. typhi belonged to phage type A. All S. paratyphi A isolates belong to phage 2. All the isolates were sensitive to chloramphenicol, cefixime and amikacin. Untreated natural water sources are unsafe for human consumption.

  5. 96-well RNA In Situ Hybridization Protocol

    OpenAIRE

    sprotocols

    2014-01-01

    Author: Berkeley Drosophila Genome Project ### 1. Materials **1.1. Probe Preparation** **1.1.1. Cell Inoculation** 1. 96-well, deep square-well round bottom plate (E&K; Scientific Ritter Riplate). - Super Broth (SB: 10 gm 4-Morpholinepropanesulfonic acid (MOPS), 20 gm Bacto Yeast Extract, 30 gm Tryptone Peptone/L). - Antibiotic (80 µg/ml final concentration Carbenicillin- for pFLC-I or pBS SK, 80 µg/ml chloramphenicol for pOT2 or pOTB7). - Multichannel pipette (Brand)...

  6. Carriage of antibiotic-resistant bacteria by healthy children.

    Science.gov (United States)

    Millar, M R; Walsh, T R; Linton, C J; Zhang, S; Leeming, J P; Bennett, P M

    2001-05-01

    The frequency of carriage of antibiotic-resistant bacteria in healthy 7- and 8-year-old children in Bristol was studied. Children born in Avon between 1 April 1991 and 31 December 1992, attending the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) 7 year follow-up clinic, formed the study population. Carriage was estimated using mouth and stool samples. None of 105 children on whom information was available had received tetracycline, chloramphenicol, ciprofloxacin or an extended-spectrum cephalosporin in the previous year. Staphylococcus aureus was isolated from mouthwashes from 200 (37.1%) of 539 children sampled. Six (3%) of the isolates were resistant to chloramphenicol or tetracycline and four (2%) were methicillin resistant. Haemophilus spp. were isolated from 369 (72%) of 513 samples and 63 (17%) were ampicillin resistant, 49 (13.3%) were erythromycin resistant and seven (1.9%) were tetracycline resistant. Branhamella catarrhalis was isolated from 333 (74%) of 450 samples. Twenty-eight (8.4%) were erythromycin resistant and 14 (4.2%) strains were tetracycline resistant. Group A beta-haemolytic streptococci were isolated from 17 of 507 children sampled. One (5.9%) was tetracycline resistant. Stool samples were returned from 335 (62%) of 539 children from whom they were requested. Eleven per cent of samples yielded Gram-negative bacilli with high-level resistance to chloramphenicol, which was frequently linked to resistance to ampicillin, spectinomycin and streptomycin. Isolates demonstrating resistance to the third-generation cephalosporin ceftazidime were recovered from 17 subjects (3.2%). Six (35%) of 17 isolates possessed extended-spectrum beta-lactamases. Healthy children carry bacteria resistant to antibiotics to which children are not usually exposed. Resistance to ceftazidime, chloramphenicol and tetracycline may be co-selected by exposure to other antibiotics used in children or may be acquired from family members, pets, other children or

  7. 氯霉素类三甲基硅衍生物的质谱特征及其残留监测

    Institute of Scientific and Technical Information of China (English)

    贺利民; 曾振灵; 刘雅红; 陈建新; 黄显会

    2004-01-01

    Mass characteristics of TMS derivative of chloramphenicol, florfenicol,and thiamphenicol were interpreted manually, respectively. Then SIM mode was performed at m/z 225, m/z 242, m/z 244, m/z 361 for CAP, m/z 178, m/z 257, m/z 259, m/z 394 for FF,and m/z 242, m/z 244, m/z 257, m/z 330 for TAP. A sensitive, reproducible gas chromatographic-mass spectrometric method was developed for simultaneous monitoring residues of fenicols in pork and tissues.

  8. Transduction of Enteric Escherichia coli Isolates with a Derivative of Shiga Toxin 2-Encoding Bacteriophage φ3538 Isolated from Escherichia coli O157:H7

    OpenAIRE

    Schmidt, Herbert; Bielaszewska, Martina; Karch, Helge

    1999-01-01

    We investigated the ability of a detoxified derivative of a Shiga toxin 2 (Stx2)-encoding bacteriophage to infect and lysogenize enteric Escherichia coli strains and to develop infectious progeny from such lysogenized strains. The stx2 gene of the patient E. coli O157:H7 isolate 3538/95 was replaced by the chloramphenicol acetyltransferase (cat) gene from plasmid pACYC184. Phage φ3538(Δstx2::cat) was isolated after induction of E. coli O157:H7 strain 3538/95 with mitomycin. A variety of strai...

  9. Post-irradiation replication and repair in UV-irradiated cells of Proteus mirabilis depends on protein synthesis and a functioning rec+ gene

    International Nuclear Information System (INIS)

    The amount of and the molecular weight of newly synthesized DNA (piDNA) as well as its repair after UV irradiation in excision-proficient strains of P.mirabilis and E.coli K12 have been compared. A fraction of post-replication repair (PRR) in P.mirabilis is found to be dependent on de novo protein synthesis after UV irradiation. Pre-irradiation by UV and pre-treatment with nalidixic acid increase the efficiency of post-irradiation replication and PRR even in the presence of chloramphenicol. An inducible repair function in P.mirabilis is supposed to stimulate post-irradiation replication and repair. (author)

  10. Salmonella serovars and antimicrobial resistance in strains isolated from wild animals in captivity in Sinaloa, Mexico.

    Science.gov (United States)

    Silva-Hidalgo, Gabriela; López-Valenzuela, Martin; Juárez-Barranco, Felipe; Montiel-Vázquez, Edith; Valenzuela-Sánchez, Beatriz

    2014-08-01

    The aim of the present study was to evaluate the frequency of antibiotic resistance in Salmonella spp. strains from wild animals in captivity at the Culiacan Zoo and the Mazatlan Aquarium in Sinaloa, Mexico. We identified 17 different Salmonella enterica serovars at a prevalence of 19.90% (Culiacan Zoo) and 6.25% (Mazatlan Aquarium). Antibiotic sensitivity tests revealed that, of the 83 strains studied, 100% were multidrug resistant (MDR). The drugs against which the greatest resistance was observed were: penicillin, erythromycin, dicloxacillin, ampicillin, cephalothin, and chloramphenicol. We therefore conclude that MDR is common among Salmonella isolates originating from wild animals in captivity in Sinaloa. PMID:25282954

  11. Transient Transfection and Expression in the Obligate Intracellular Parasite Toxoplasma gondii

    Science.gov (United States)

    Soldati, Dominique; Boothroyd, John C.

    1993-04-01

    Toxoplasma gondii is a protozoan pathogen that produces severe disease in humans and animals. This obligate intracellular parasite provides an excellent model for the study of how such pathogens are able to invade, survive, and replicate intracellularly. DNA encoding chloramphenicol acetyltransferase was introduced into T. gondii and transiently expressed with the use of three vectors based on different Toxoplasma genes. The ability to introduce genes and have them efficiently and faithfully expressed is an essential tool for understanding the structure-function relation of genes and their products.

  12. Translocation of integron-associated resistance in a natural system: Acquisition of resistance determinants by Inc P and Inc W Plasmids from Salmonella enterica Typhimurium DT104

    DEFF Research Database (Denmark)

    Sandvang, Dorthe; Diggle, M.; Platt, D.J.

    2002-01-01

    Salmonella enterica Typhimurium DT104, 961368, a veterinary field isolate that encodes a chromosomal cluster of resistance genes as well as two integrons, was used to study the mobility of resistance cassettes (aadA2 and pse-1) and nonintegron-associated resistance determinants (chloramphenicol and...... determinate the genetic content. Translocation to R751 and R388 was associated with the loss of the indigenous trimethoprim cassette to both plasmids and also acquisition of sulfonamide resistance by R751 and RP4::Tn7, which indicated movement of the 3' terminus of one or both of the DT104 integrons...

  13. A simple cultural method for the presumptive detection of the yeasts Brettanomyces/Dekkera in wines

    OpenAIRE

    Couto, J. A.; Barbosa, A; Hogg, T.

    2005-01-01

    The development of a simple and reliable procedure, compatible with routine use in wineries, for the presumptive detection of Brettanomyces/Dekkera from wine and wine-environment samples. Methods and Results: The method of detection of these yeasts employs a selective enrichment medium. The medium contains glucose (10 g l⁻¹1) as carbon and energy source, cycloheximide (20 mg l⁻¹1) to prevent growth of Saccharomyces, chloramphenicol (200 mg l⁻¹1) to prevent growth of bacteria and p-coumaric ac...

  14. Effects of disinfectants and antibiotics on the anaerobic digestion of piggery waste

    Energy Technology Data Exchange (ETDEWEB)

    Poels, J.; Van Assche, P.; Verstraete, W.

    1984-01-01

    The effects of disinfectants and antibiotics on the anaerobic digestion of piggery waste were investigated. The disinfectants Tego 51, Dettol, NaOCl and Creolin, and the antibiotics, chlortetracyclin, tylosin, erythromycin, chloramphenicol, bacitracin and virginiamycin were tested at different concentrations. At concentrations normally used in practice, no inhibitory effect on methanisation process was detected. However, higher concentrations of the antimicrobial agents, Dettol, Creolin, bacitracin and virginiamycin, markedly inhibited biogas production. In order to minimize possible digester failures, farmers are advised to respect the normal recommended dose and to use low-toxicity antimicrobial agents. (Refs. 8).

  15. ENDOGENAL COLONIZATION OF GRAPES BERRIES

    OpenAIRE

    Dana Tančinová; Ľubomír Rybárik; Zuzana Mašková; Soňa Felšöciová; Miroslava Císarová

    2015-01-01

    The aim of study was to detect the microscopic filamentous fungi from wine surface of sterilized grapes berries of Slovak origin. We analyzed 21 samples of grapes, harvested in the year 2012 of various wine-growing regions. For the isolation of species we used the method of direct plating surface-sterilized berries (using 0.4% freshly pre-pared chlorine) on DRBC (Dichloran Rose Bengal Chloramphenicol agar). The cultivation was carried at 25±1°C, for 5 to 7 days. A total number of 2541 fungal ...

  16. Unraveling photosystems. Progress report

    International Nuclear Information System (INIS)

    Each of the three cyanobacteria examined contains two or more genes for the B protein of photosystem II of photosynthesis. One of these genes from the cyanobacterium Fremyella diplosiphon has been sequenced. Synthetic oliogopeptides were used to raise antibodies to two ten amino acid-long sequences of the 32 kilodalton B protein. To examine whether chloroplast promoter sequences (and hence possibly chloroplast genes) can function in cyanobacteria, we have used a series of plasmids containing the chloramphenicol acetyl transferase (CAT) gene minus its bacterial promoter. It appears that chloroplast promoters are recognized in cyanobacteria and act efficiently

  17. Caavuranamide, a novel steroidal alkaloid from the ripe fruits of Solanum caavurana Vell. (Solanaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Vaz, Nelissa Pacheco; Santos, Erica L.; Marques, Francisco A.; Maia, Beatriz H.L.N. Sales, E-mail: noronha@ufpr.br [Departamento de Quimica, Universidade Federal do Parana, Centro Politecnico, Curitiba, PR (Brazil); Costa, Emmanoel V. [Departamento de Quimica, Universidade Federal de Sergipe, Sao Cristovao, SE (Brazil); Mikich, Sandra Bos [Laboratorio de Ecologia, Embrapa Florestas, Colombo, PR (Brazil); Braga, Raquel M. [Instituto de Quimica, Universidade Estadual de Campinas, SP (Brazil); Delarmelina, Camila; Duarte, Marta C.T. [Divisao de Microbiologia, Centro Pluridisciplinar de Pesquisas Quimicas Biologicas e Agricolas (CPQBA), Universidade Estadual de Campinas, SP (Brazil); Duarte, Marta C.T.; Ruiz, Ana Lucia T.G.; Souza, Vanessa H.S.; Carvalho, Joao E. de [Divisa de Farmacologia e Toxicologia, Centro Pluridisciplinar de Pesquisas Quimicas Biologicas e Agricolas (CPQBA), Universidade Estadual de Campinas, SP (Brazil)

    2012-07-01

    Phytochemical investigation of the ripe fruits of Solanum caavurana Vell. (Solanaceae) afforded a novel steroidal alkaloid with spirosolane-type skeleton, named as caavuranamide, together with the alkaloids 4-tomatiden-3-one and 5{alpha}-tomatidan-3-one. Their structures were elucidated on the basis of spectroscopic methods. The antiproliferative and antimicrobial activities for the ethanolic extract, sub-fractions obtained from partition and acid-base treatment were also evaluated. Caavuranamide showed antibacterial activity similar to the chloramphenicol positive control against Rhodococcus equi. (author)

  18. Control of lipopolysaccharide biosynthesis and release by Escherichia coli and Salmonella typhimurium.

    OpenAIRE

    Ishiguro, E E; Vanderwel, D; Kusser, W

    1986-01-01

    The influence of the relA gene on lipopolysaccharide (LPS) biosynthesis and release by Escherichia coli and Salmonella typhimurium was investigated. Similar results were obtained with both species. The incorporation of [3H]galactose into LPS by galE mutants was inhibited by at least 50% (as compared with normal growing controls) during amino acid deprivation of relA+ strains. This inhibition could be prevented by the treatment of the amino acid-deprived relA+ bacteria with chloramphenicol, a ...

  19. Positive Selection for Loss-of-Function tat Mutations Identifies Critical Residues Required for TatA Activity

    OpenAIRE

    Hicks, Matthew G.; Lee, Philip A.; Georgiou, George; Berks, Ben C.; Palmer, Tracy

    2005-01-01

    The Tat system, found in the cytoplasmic membrane of many bacteria, is a general export pathway for folded proteins. Here we describe the development of a method, based on the transport of chloramphenicol acetyltransferase, that allows positive selection of mutants defective in Tat function. We have demonstrated the utility of this method by selecting novel loss-of-function alleles of tatA from a pool of random tatA mutations. Most of the mutations that were isolated fall in the amphipathic r...

  20. Antimicrobial susceptibility of listeria monocytogenes from food products

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Knöchel, Susanne; Hasman, Henrik

    2007-01-01

    susceptibility to ceftiofur, chloramphenicol, ciprofloxacin, erythromycin, florfenicol, penicillin, spectinomycin, streptomycin, tetracycline, tiamulin, trimethoprim, and co-trimoxazole, and the disinfectants benzalkonium chloride and triclosan, by determination of minimum inhibitory concentrations (MICs). All...... isolates were resistant to ceftiofur, but susceptible to the other antibiotics. A single isolate had a MIC of 4 mg/L for ciprofloxacin. For tiamulin. the MIC values were around the breakpoint used. Most isolates had MICs for triclosan at 16 mg/L. The MICs for benzalkonium chloride formed a bimodal...

  1. Genetic analysis of the conjugal transfer determinants encoded by the streptococcal broad-host-range plasmid pIP501.

    OpenAIRE

    Krah, E R; Macrina, F L

    1989-01-01

    pIP501 is a 30.2-kilobase (kb) broad-host-range conjugative streptococcal plasmid which encodes chloramphenicol and erythromycin resistance. A smaller conjugation-proficient derivative of pIP501 has been constructed and designated pVA1702. pVA1702 is 25.2 kb, encodes only kanamycin resistance, and confers conjugative ability in an Enterococcus faecalis mating system. The temperature-sensitive transposon delivery vectors pTV1ts and pTV32 carrying Tn917 and Tn917lac, respectively, were used to ...

  2. Resistance to antibiotics in heterotrophic bacteria as a result of environmental pollution

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    Maria Bartoszewic

    2014-12-01

    Full Text Available Introduction. The aim of the study was to investigate resistance to selected antibiotics in Escherichia coli and Enterococcus faecalis strains that were isolated from water collected from ten streams within the administrative boundaries of the city of Sopot. Material and methods. 114 E. coli strains and 57 E. faecalis strains were studied. Antibiotic resistance was determined by the disc diffusion method using antibiotic-impregnated discs. Results. The isolated E. coli strains were resistant to chloramphenicol (21%, cefepime (51%, tetracycline (41%, imipenem (35%, cephazoline (62% and gentamicin (90%. E. faecalis isolates showed resistance to erythromycin (75%, chloramphenicol (21% and imipenem (33%. The relationship between the level of antibiotic resistance, the origin of water sample and the level of water contamination with E. coli and Enterococcus faecalis bacteria in the investigated streams was analyzed. Conclusions. Based on the obtained results, it was determined that multi-drug resistant bacterial strains of E. coli and E. faecalis are present in the investigated surface waters.

  3. Nondermatophytic moulds as a causative agent of onychomycosis in Tehran

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    Bassiri-Jahromi Shahindokht

    2010-01-01

    Full Text Available Background: In the last few years the number of cases of nondermatophytic onychomycosis has greatly increased. Aim: To evaluate the incidence, the clinic characteristics, and predisposing factors of nondermatophytic onychomycosis. Materials and Methods: All collected specimens were analyzed by direct microscopy and culture. Microscopic examination of these specimens was carried out in potassium hydroxide solution (20% with dimethyl sulfoxide (4%. These specimens were cultured on sabouraud′s glucose agar with chloramphenicol and sabouraud′s glucose agar with chloramphenicol and cycloheximide. Cultures were incubated at 25ΊC for up to 28 days and checked twice weekly for growth. Results: Nondermatophytic onychomycosis were 11.5% of all onychomycosis. We found that Aspergillus spp. were the more responsible etiologic agents of nondermatophytic onychomycosis, resulting in a total of 28 patients (59.6%. In our study other causative agents were Acremonium spp. (17%, Fusarium spp. (12.7%, Geotrichum spp. (4.2%, Trichosporun spp., (4.2% and Scopulariopsis spp (2.1%. In our patients moulds onychomycosis developed mainly in toenails (74.5%. Conclusion: Knowing the exact pathogen is important and has implications in therapy and prognosis.

  4. [Determination of 35 antibiotic residues of tetracyclines, sulfonamides, penicillins, macrolides and amphenicols in milk by liquid chromatography-tandem mass spectromtery].

    Science.gov (United States)

    Wang, Hao; Zhao, Li; Yang, Hongmei; Pan, Hongyan; Shi, Hailiang; Qian, Cong; Zhang, Shan

    2015-09-01

    A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the simultaneous determination of 35 antibiotic residues of tetracyclines, sulfonamides, penicillins, macrolides and amphenicols in milk. The samples were extracted with alkaline acetonitrile and McIlvaine buffer solution under ultrasonication. The separation of target compounds was performed on an Eclipse XDB-C, column (150 mm x 2.1 mm, 3.5 µm) with gradient elution at a flow rate of 0.25 mL/min, and with an injection volume of 10 µL. The identification and quantification of the compounds were completed by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring ( MRM) mode. The limits of detection were all below 10.0 µg/kg. The average spiked recoveries of the method ranged from 70. 1% to 109. 9% with relative standard deviations (RSDs) of 2.89%-9.99%. After validation, the method was applied to the analysis of antibiotic residues in milk products in China. Fifty samples were screened under the well defined methodology, and the results showed that chloramphenicol, only in one sample, was monitored with the content of 0.48 µg/kg. A risk of contamination of milk with chloramphenicol has been determined to exist. Therefore this method is convenient, rapid, sensitive and reliable, and can be successfully applied to the simultaneous detection of the 35 antibiotic residues of tetracyclines, sulfonamides, penicillins, macrolides and amphenicols in milk. PMID:26753289

  5. Antibiotic Resistance Patterns of Gram-Negative Psychrotrophic Bacteria from Bulk Tank Milk.

    Science.gov (United States)

    Decimo, Marilù; Silvetti, Tiziana; Brasca, Milena

    2016-04-01

    Bacterial resistance to antibiotics is a major global health problem and resistance of Pseudomonadaceae and Enterobacteriaceae is a serious concern. We investigated the prevalence of drug-resistance in a total of 80 psychrotrophic strains from bulk milk belonging to Pseudomonas genus (n. 63) and Enterobacteriaceae group (n. 17). All the strains were tested against 16 antibiotics. Pseudomonas were further investigated for their sensitivity against 12 additional antibiotics. Pseudomonas showed a high susceptibility toward fluoroquinolones, aminoglycosides, and piperacillin and, to a lesser extent, to imipenem, ceftazidime, cefepime. Thirty-five out of 63 Pseudomonas strains were susceptible to meropenem, while among antibiotics for which recommended breakpoints are not yet available, 55% of Pseudomonas strains had no inhibition halo in presence of nitrofurantoin, highlighting a resistance toward this drug. The results obtained in this study indicate a high efficiency of fluoroquinolones, chloramphenicol (94%), and kanamycin (76%) for Enterobacteriaceae while a high prevalence of resistant strains was found to ampicillin (13/17). Serratia marcescens is highly susceptible to fluoroquinolones, chloramphenicol, and kanamycin. Moreover, mupirocin seems to be the new antibiotic with the less efficacy for Enterobacteriaceae, with 41% of strains without halo, pointing out an important resistance. Further knowledge on resistance to known and new antibiotics among Pseudomonas species and Enterobacteriaceae of milk origin was acquired. PMID:26910385

  6. Effects of γ-radiation on the fungus Alternaria alternata in artificially inoculated cereal samples

    International Nuclear Information System (INIS)

    The objective of this study was to evaluate the effects of different γ-radiation doses on the growth of Alternaria alternata in artificially inoculated cereal samples. Seeds and grains were divided into four groups: Control Group (not irradiated), and Groups 1, 2 and 3, inoculated with an A. alternata spore suspension (1x106 spores/mL) and exposed to 2, 5 and 10 kGy, respectively. Serial dilutions of the samples were prepared and seeded on DRBC (dichloran rose bengal chloramphenicol agar) and DCMA (dichloran chloramphenicol malt extract agar) media, after which the number of colony-forming units per gram was determined in each group. In addition, fungal morphology after irradiation was analyzed by scanning electron microscopy (SEM). The results showed that ionizing radiation at a dose of 5 kGy was effective in reducing the growth of A. alternata. However, a dose of 10 kGy was necessary to inhibit fungal growth completely. SEM made it possible to visualize structural alterations induced by the different γ-radiation doses used.

  7. Antimicrobial resistance in food and clinical Aeromonas isolates.

    Science.gov (United States)

    Palú, Angela Peres; Gomes, Luciana Martins; Miguel, Marco Antônio Lemos; Balassiano, Ilana Teruzkin; Queiroz, Mara Lucia Penna; Freitas-Almeida, Angela Corrêa; de Oliveira, Selma Soares

    2006-08-01

    This study highlights the incidence of resistance and the presence of plasmids in human and food isolates of Aeromonas in Brazil. A total of 83 Aeromonas spp. strains (28 isolated from human and 55 from fresh lettuce) were studied. Thirty-five were identified as A. hydrophila complex and 48 as A. caviae complex. All strains were shown to be susceptible to imipenem, amikacin, gentamicin, tobramycin and ciprofloxacin by the disk diffusion method. Resistance to antimicrobial agents was observed in strains of both food and clinical origin. The food strains were resistant to ampicillin/sulbactam, cefoxitin and tetracycline, while the clinical strains presented resistance to ampicillin/sulbactam, cefotaxime, ceftazidime, cefoxitin, sulfamethoxazole/trimethoprim, chloramphenicol and tetracycline. The minimal inhibitory concentrations of chloramphenicol, tetracycline and sulfamethoxazole/trimethoprim were tested by agar dilution. Thirteen strains isolated from vegetables were resistant to tetracycline (MIC 16 microg ml-1). Two A. hydrophila strains and one A. caviae strain presented extracromosomal DNA (3 and 15 kb plasmids, respectively). The tetracycline resistance phenotype determinant was related to the 15 kb plasmid according to cure and transformation experiments. PMID:16943044

  8. Comparative antibiogram of coagulase-negative Staphylococci (CNS associated with subclinical and clinical mastitis in dairy cows

    Directory of Open Access Journals (Sweden)

    B. K. Bansal

    2015-03-01

    Full Text Available Aim: The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results. Materials and Methods: The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17. Results: Isolates were highly susceptible to chloramphenicol (98.3%, gentamicin (93.1%, streptomycin (91.4%, linezolid (91.4%, ceftixozime (87.9%, cloxacillin (86.2%, clotrimazole (86.2%, bacitracin (86.2%, enrofloxacin (84.5% and ceftrioxone + tazobactum (70.7%, while resistance was observed against amoxicillin (77.6%, penicillin (75.9%, ampicillin (74.1% and cefoperazone (51.7%. Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates. Conclusion: CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.

  9. AXENIC CULTURE OF FREE-LIVING CONCHOCELIS OF PORPHYRA YEZOENSIS AND PORPHYRA HAITANENSIS

    Institute of Scientific and Technical Information of China (English)

    刘会莲; 帅莉; 段德麟; 徐怀恕

    2002-01-01

    After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra haitanensis, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to determine the effectiveness of each antibiotic in eliminating contaminating microorganisms. Five of 12 antibiotics tested were selected and used to produce the axenic cultures in this study, which showed that 200 μg/mL streptomycin, 250 μg/mL penicillin, 252 μg/mL kanamycin, 30 μg/mL neomycin, 200 μg/mL chloramphenicol were effective concentrations for eliminating microorganisms from conchocelis when antibiotics were added singly step by step; whereas simultaneous combination of 150 μg/mL streptomycin, 250 (or 350) μg/mL penicillin, 150 (or 250) μg/mL kanamycin, 70 μg/mL neomycin and 200 μg/mL chloramphenicol was also effective for producing the axenic cultures. However, it seemed that the treatments with antibiotics applied individually were more feasible than those with all antibiotics added at the same time. This may be due to the combined inhibiting effect of antibiotics on the growth and development of conchocelis.

  10. Preliminary phytochemical screening and Bioactivity of selected Indian Medicinal plants

    Directory of Open Access Journals (Sweden)

    AG Devi Prasad

    2013-04-01

    Full Text Available The methanolic crude extracts of Chonemorpha fragrans (Moon, Chilocarpus malabaricus Bedd Madhuka longifolia (Koenig J.F.Macbr, Pittosporum neelgherrense Wightt, Raphidophora pertusa (Roxb. Schott, Fagraea ceilanica Thunb and Rauvolfia tetraphylla L.  were screened for the presence of phytoconstituents and their ability to possess antimicrobial and  free radical scavenging ability using Chloramphenicol,The methanolic crude extracts of Chonemorpha fragrans (Moon Alston, Chilocarpus malabaricus Bedd., Madhuka longifolia (Koenig J.F.Macbr., Pittosporum neelgherrense Wightt., Raphidophora pertusa (Roxb. Schott., Fagraea ceilanica Thunb., and Rauvolfia tetraphylla L., were screened for the presence of phyto-constituents and their ability to possess antimicrobial and free radical scavenging ability using chloramphenicol, cephoperazone and ascorbic acid as respective standards. Antimicrobial activity was evaluated by Kirby-Bauer disc diffusion method and free radical scavenging activity was evaluated using 1,1-diphenyl-2-picryl hydrazyl (DPPH free radical and reducing power assay. Pittosporum neelgherrense showed better overall antimicrobial activity and Madhuka longifolia proved better antioxidant ability possessing low IC50 valueof30 µg/ml compared to the other selected medicinal plants. The highest total phenol content was found to be in Chonemorpha fragrans with the value 88±0.121mg/g. The present study reveals that the selected plants serve as a source of antimicrobial and antioxidant drugs in future and thus, can find applications in food and pharmaceutical industries.

  11. Prevalence and antimicrobial resistance of Campylobacter in raw milk in the selected areas of Poland.

    Science.gov (United States)

    Wysok, B; Wiszniewska-Łaszczych, A; Uradziński, J; Szteyn, J

    2011-01-01

    During the recent years, an immense increase in the number of food poisoning cases in people caused by Campylobacter (C.) species has occurred. Raw milk, next to poultry meat, is considered the most frequent cause of food poisoning in people caused by the subject bacteria, although it is not always possible to isolate Campylobacter cells from the incriminated milk. Most probably this difficulty is caused by low concentration of the pathogen in milk at the level of 2/3 cells/ml although even such low concentration represents risk to human health. The present study was aimed at determining the occurence of Campylobacter bacteria in milk originating from selected regions of Poland. The isolation method applied in this work was effective in recovering as few as 0.1 cell of Campylobacter per g of food. Among 150 bulk milk samples tested, Campylobacter spp. was isolated from 7 (4.6%) ones. The biochemical identification of the isolated strains conducted by means of conventional biochemical tests as well as by applying the API - Campy tests revealed that all the isolates belonged to the C. jejuni species. Determination of resistance to antibiotics was performed by means of the diffusion disks method for the following antibiotics: gentamicin, ciprofloxacin, ampicillin, chloramphenicol, erythromycin, doxycyclin and tetracycline. Among 7 isolates tested, all were susceptible to ampicillin, chloramphenicol, erythromycin and gentamicin, 28.5% to doxycyclin and 14.2% to tetracycline and ciprofloxacin. PMID:21957744

  12. Kemampuan Susu Fermentasi Lactobacillus plantarum Menghambat Salmonella typhymurium Secara In Vitro

    Directory of Open Access Journals (Sweden)

    Zuraida Hanum

    2010-10-01

    Full Text Available The ability of Lactobacillus plantarum fermented milk to inhibit Salmonella typhymurium in vitro ABSTRACT. This research used Lactobacillus plantarum as a milk starter (concentration 3, 4, 5 % and incubated for 48 hours at room temperature. Observation fermented begin from the first day of this product until 7 days and its still stored at room temperature. First analysis conducted on milk in this research were Storch, pH, acidity titration, fat, and dry matter. Milk fermentation analysis of Lactobcillus plantarum including pH, degree of dornik acidity and microbe activity test. Experimental design used is Repeated Measurement with three replications. Data colected analyzed by ANOVA test. If there is significant different between treatments, followed by Least Significant Test. Complete pasteurization result test (Storch found that milk stay white, it means that peroksidase enzyme completely disappear and milk completely pasteurization. The ability of suppressing observed by Salmonella typhymurium in Nutrient Agar and challenge with Lactobacillus plantarum fermented milk 3%, 4% and 5% (50 μl/well. Tetracyline, chloramphenicol and a plain paper disc are used as control. Lactobacillus plantarum fermented milk of starter concentration 5%-first day has the biggest inhabitation zone by Salmonella typhimurium (9.39 mm. Range of pH showed between 4.84 to 4.14 and the acidity between 114.67 0D to 365.67 0D. Sensitivity test showed that Salmonella typhymurium more sensitive than chloramphenicol and tetracyline antibiotic.

  13. Antibiotic susceptibility profiles of some Vibrio strains isolated from wastewater final effluents in a rural community of the Eastern Cape Province of South Africa

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    Igbinosa Etinosa O

    2010-05-01

    Full Text Available Abstract Background To evaluate the antibiogram and antibiotic resistance genes of some Vibrio strains isolated from wastewater final effluents in a rural community of South Africa. V. vulnificus (18, V. metschnikovii (3, V. fluvialis (19 and V. parahaemolyticus (12 strains were isolated from final effluents of a wastewater treatment plant (WWTP located in a rural community of South Africa. The disk diffusion method was used for the characterization of the antibiogram of the isolates. Polymerase chain reaction (PCR was employed to evaluate the presence of established antibiotic resistance genes using specific primer sets. Results The Vibrio strains showed the typical multidrug-resistance phenotype of an SXT element. They were resistant to sulfamethoxazole (Sul, trimethoprim (Tmp, cotrimoxazole (Cot, chloramphenicol (Chl, streptomycin (Str, ampicillin (Amp, tetracycline (Tet nalidixic acid (Nal, and gentamicin (Gen. The antibiotic resistance genes detected includes dfr18 and dfrA1 for trimethoprim; floR, tetA, strB, sul2 for chloramphenicol, tetracycline, streptomycin and sulfamethoxazole respectively. Some of these genes were only recently described from clinical isolates, demonstrating genetic exchange between clinical and environmental Vibrio species. Conclusions These results demonstrate that final effluents from wastewater treatment plants are potential reservoirs of various antibiotics resistance genes. Moreover, detection of resistance genes in Vibrio strains obtained from the wastewater final effluents suggests that these resistance determinants might be further disseminated in habitats downstream of the sewage plant, thus constituting a serious health risk to the communities reliant on the receiving waterbodies.

  14. Conjunctival bacterial flora and antibiotic resistance pattern in patients undergoing cataract surgery

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    Arantes Tiago Eugênio Faria e

    2006-01-01

    Full Text Available PURPOSE: To evaluate the conjunctival bacterial flora and its antibiotic resistance pattern in eyes of patients undergoing cataract surgery. METHODS: From August to October 2004, 50 patients undergoing cataract surgery in the "Fundação Altino Ventura", Recife, Brazil, were prospectively evaluated. Conjunctival material was obtained on the day of surgery, before the application of topical anesthetic, antibiotic or povidone-iodine. The collected material was inoculated and bacterioscopic analysis was carried out. In the cases where there was bacterial growth, antibiotic susceptibility tests and cultures, for isolation and identification of the bacteria, were performed. RESULTS: Of the 50 eyes, 43 (86.0% had positive cultures. The coagulase-negative Staphylococcus (CNS, found in 27 (54.0% eyes, was the most frequent organism. More than 90% of the isolates of this bacterium were susceptible to cephalotin, vancomycin, chloramphenicol, ofloxacin and gatifloxacin; 70 to 90% were susceptible to gentamicin, cefotaxime, oxacillin and ciprofloxacin; and less than 70% were sensible to neomycin. Four (10.5% of the bacterial isolates were resistant to four or more antibiotics, two of them were CNS. CONCLUSION: The most frequent bacterium in the conjunctival flora is the coagulase-negative Staphylococcus. The isolates of this organism showed low susceptibility rate to neomycin, and high susceptibility rates to cephalotin, vancomycin, chloramphenicol, ofloxacin and gatifloxacin.

  15. Frequency and Antibiogram of Vancomycin Resistant Enterococcus in a Tertiary Care Hospital

    International Nuclear Information System (INIS)

    Objective: To determine the frequency of Vancomycin Resistant Enterococcus (VRE) in a tertiary care hospital of Rawalpindi, Pakistan. Study Design: Observational, cross-sectional study. Place and Duration of Study: Department of Microbiology, Army Medical College, Rawalpindi, from May 2011 to May 2012. Methodology: Vancomycin resistant Enterococcus isolated from the clinical specimens including blood, pus, double lumen tip, ascitic fluid, tracheal aspirate, non-directed bronchial lavage (NBL), cerebrospinal fluid (CSF), high vaginal swab (HVS) and catheter tips were cultured on blood agar and MacConkey agar, while the urine samples were grown on cystine lactose electrolyte deficient agar. Later the antimicrobial susceptibility testing of the isolates was carried out using the modified Kirby-Bauer disc diffusion method on Mueller Hinton agar. Results: A total of 190 enterococci were isolated. Of these, 22 (11.57%) were found to be resistant to vancomycin. The antimicrobial sensitivity pattern revealed maximum resistance against ampicillin (86.36%) followed by erythromycin (81.81%) and gentamicin (68.18%) while all the isolates were 100% susceptible to chloramphenicol and linezolid. Conclusion: The frequency of VRE was 11.57% with the highest susceptibility to linezolid and chloramphenicol. (author)

  16. Ionic liquid-anionic surfactant based aqueous two-phase extraction for determination of antibiotics in honey by high-performance liquid chromatography.

    Science.gov (United States)

    Yang, Xiao; Zhang, Shaohua; Yu, Wei; Liu, Zhongling; Lei, Lei; Li, Na; Zhang, Hanqi; Yu, Yong

    2014-06-01

    An ionic liquid-anionic surfactant based aqueous two-phase extraction was developed and applied for the extraction of tetracycline, oxytetracycline and chloramphenicol in honey. The honey sample was mixed with Na2EDTA aqueous solution. The sodium dodecyl sulfate, ionic liquid 1-octyl-3-methylimidazolium bromide and sodium chloride were added in the mixture. After the resulting mixture was ultrasonically shaken and centrifuged, the aqueous two phase system was formed and analytes were extracted into the upper phase. The parameters affecting the extraction efficiency, such as the volume of ionic liquid, the category and amount of salts, sample pH value, extraction time and temperature were investigated. The limits of detection of tetracycline, oxytetracycline and chloramphenicol were 5.8, 8.2 and 4.2 μg kg(-1), respectively. When the present method was applied to the analysis of real honey samples, the recoveries of analytes ranged from 85.5 to 110.9% and relative standard deviations were lower than 6.9%. PMID:24767438

  17. Prevalence of antimicrobial resistance in faecal enterococci from vet-visiting pets and assessment of risk factors.

    Science.gov (United States)

    Leite-Martins, L; Mahú, M I; Costa, A L; Bessa, L J; Vaz-Pires, P; Loureiro, L; Niza-Ribeiro, J; de Matos, A J F; Martins da Costa, P

    2015-06-27

    The objective of this study was to determine the prevalence of antimicrobial resistance (AMR) exhibited by enterococci isolated from faeces of pets and its underlying risk factors. From September 2009 to May 2012, rectal swabs were collected from 74 dogs and 17 cats, selected from the population of animals visiting the Veterinary Hospital of University of Porto, UPVet, through a systematic random procedure. Animal owners answered a questionnaire about the risk factors that could influence the presence of AMR in faecal enterococci. Enterococci isolation, identification and antimicrobial (AM) susceptibility testing were performed. Data analyses of multilevel, univariable and multivariable generalised linear mixed models were conducted. From all enterococci isolated (n=315), 61 per cent were considered multidrug-resistant, whereas only 9.2 per cent were susceptible to all AMs tested. Highest resistance was found to tetracycline (67.0 per cent), rifampicin (60.3 per cent), azithromycin (58.4 per cent), quinupristin/dalfopristin (54.0 per cent) and erythromycin (53.0 per cent). Previous fluoroquinolone treatments and coprophagic habits were the features more consistently associated with the presence of AMR for three (chloramphenicol, ciprofloxacin and azithromycin) and seven (tetracycline, rifampicin, gentamicin, chloramphenicol, ciprofloxacin, erythromycin and azithromycin), respectively, out of nine AMs assessed. Evaluating risk factors that determine the presence of drug-resistant bacteria in pets, a possible source of resistance determinants to human beings, is crucial for the selection of appropriate treatment guidelines by veterinary practitioners. PMID:26078332

  18. Macrolide-lincosamide-streptogramin B resistance phenotypes in clinical staphylococcal isolates.

    Science.gov (United States)

    Cetin, Emel Sesli; Gunes, Hayati; Kaya, Selcuk; Aridogan, Buket Cicioglu; Demirci, Mustafa

    2008-04-01

    The prevalence of macrolide-lincosamide-streptogramin B (MLSB) resistance as well as the MLSB resistance phenotypes were investigated by the double-disk diffusion test among 532 clinical staphylococci isolates in a Turkish university hospital. The activity of other antimicrobials, including trimethoprim/sulfamethoxazole, telithromycin, quinupristin/dalfopristin, linezolid, gentamicin, chloramphenicol, ciprofloxacin and vancomycin, was also evaluated. Of 532 isolates, 38.5% were resistant to MLSB antibiotics; 63.9% of the resistant isolates exhibited a constitutive phenotype (cMLSB) whereas 36.1% expressed an inducible resistance phenotype (iMLSB). MLSB resistance was more prevalent among coagulase-negative staphylococci (CoNS) strains. Oxacillin-resistant strains exhibited significantly higher MLSB resistance rates compared with oxacillin-susceptible strains (Pquinupristin/dalfopristin, the most effective antibiotics were telithromycin and chloramphenicol among all isolates. Susceptibility rates to other antibiotics tested were higher among isolates without MLS(B) resistance than isolates with MLSB resistance. The detection of a considerable rate (43.5%) of iMLSB resistance among erythromycin-resistant/clindamycin-susceptible strains suggests that the true percentage of clindamycin resistance may be underestimated if testing for inducible resistance is not performed. PMID:18206352

  19. Characterization of Salmonella Enterica Serotype Typhimurium from Outpatients of 28 Hospitals in Henan Province in 2006

    Institute of Scientific and Technical Information of China (English)

    MIN ZHU; ZHI-QIANG XIE; LI-SHI ZHANG; SHENG-LI XIA; WEI-ZHONG YANG; LU RAN; ZI-JUN WANG

    2009-01-01

    Objective To characterize the diarrheal patients with Salmonella typhimurium (S. typhimurium) infections and to set up the first baseline for 5. typhimurium pulsed-field gel electrophoresis (PFGE) patterns in Henan province, thus laying a foundation for comprehensive surveillance of Salmonella in human as well as foods. Methods S. typhimurium isolates recovered from outpatients with diarrhea in Henan province from May to October of 2006 were characterized. Antimicrobial susceptibility tests of 8 antimicrobial agents and PFGE were carried out to analyze the 5. typhimurium isolates. Results Twenty-four (0.9%) S. typhimurium isolates were identified from 2661 stool specimens of diarrheal cases. Eighty-eight percent of isolates showed resistance to at least one antimicrobial agent. The resistance to chloramphenicol (79%) was most common. Fifty-eight percent of isolates were resistant to ciprofloxacin. All the 14 ciprofloxacin-resistant isolates were resistant to more than five antimicrobial agents. Thirty-three percent of 5. typhimurium isolates were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (R-type ACSSuT). Eight antimicrobia-resistant phenotypes were found among the 24 isolates in 16 PFGE patterns. Conclusion The rate of multidrug-resistant S. typhimurium is relatively high in S. typhimurium PFGE patterns of Henan province. Multidrug-resistant S. typhimurium should be considered a public health threat.

  20. A prospective study on evaluation of pathogenesis, biofilm formation, antibiotic susceptibility of microbial community in urinary catheter

    Science.gov (United States)

    Younis, Khansa Mohammed; Usup, Gires; Ahmad, Asmat

    2015-09-01

    This study is aimed to isolate, detect biofilm formation ability and antibiotic susceptibility of urinary catheter adherent microorganisms from elderly hospitalized patient at the Universiti Kebangsaan Malaysia Medical Center. Microorganisms were isolated from three samples of urinary catheters (UC) surface; one of the acute vascular rejection patient (UCB) and two from benign prostate hyperplasia patients (UCC and UCD). A total of 100 isolates was isolated with 35 from UCB, 38 (UCC) and 28 (UCD). Ninety six were identified as Gram-negative bacilli, one Gram-positive bacilli and three yeasts. Results of biofilm forming on sterile foley catheter showed that all the isolates can form biofilm at different degrees; strong biofilm forming: 32% from the 35 isolates (UCB), 25% out of 38 isolates (UCC), 26% out of 28 isolates (UCD). As for moderate biofilm forming; 3% from UCB, 10% from UCC and 2% from UCD. Weak biofilm forming in UCC (3%). The antibiotic susceptibility for (UCB) isolates showed highly resistant to ampicillin, novobiocin and penicillin 100 (%), kanamycin (97%), tetracycline (94%), chloramphenicol (91%), streptomycin (77%) and showed low level of resistance to gentamycin (17%), while all the isolates from (UCC-D) showed high resistant towards ampicillin and penicillin, novobiocin (94%), tetracycline (61%), streptomycin (53%), gentamycin (50%) and low level of resistance to kanamycin (48%), chloramphenicol (47%). The findings indicate that these isolates can spread within the community on urinary catheters surface and produce strong biofilm, therefore, monitoring antibiotic susceptibility of bacteria isolated in the aggregation is recommended.

  1. Distribution and antimicrobial resistance of enteric pathogens in Chinese paediatric diarrhoea: a multicentre retrospective study, 2008-2013.

    Science.gov (United States)

    Zhang, H; Pan, F; Zhao, X; Wang, G; Tu, Y; Fu, S; Wang, J; Pan, J; Song, J; Wang, W; Jin, Z; Xu, H; Ren, Y; Li, Y; Zhong, N

    2015-09-01

    The enteric pathogens causing diarrhoea impair children's health severely. This study retrospectively analysed 1577 pathogens isolated from inpatients and outpatients in six hospitals located in Northern (Inner Mongolia), Northeastern (Hebei), Eastern (Shanghai and Jiangsu), Southern (Hainan) and Central (Hubei) China between 2008 and 2013. Of the 1577 enteric pathogens, Salmonella presented with the highest frequency (36·0%), followed by diarrhoeagenic Escherichia coli (23·7%), Staphylococcus aureus (15·0%), Shigella (13·1%), and Aeromonas (4·6%). The predominant pathogens varied in different regions of China, with Salmonella most prevalent in Shanghai and Hainan, diarrhoeagenic E. coli most prevalent in Inner Mongolia, Jiangsu and Hubei, and Shigella most prevalent in Hebei. Enteric pathogens were more frequently isolated in males (56·9%) than in females (43·1%). The highest proportion of all enteric pathogens was found in infants (67·6%) with a peak in summer and autumn (68·5%). Antimicrobial susceptibility assay demonstrated that Shigella was more resistant to ampicillin, ceftriaxone and sulfamethoxazole than Salmonella. Of the top two serotypes in Salmonella, Typhimurium was more resistant to ciprofloxacin, sulfamethoxazole and chloramphenicol than Enteritidis (P sulbactam, ciprofloxacin, and chloramphenicol were significantly higher than those of Shigella sonnei (P < 0·001). Multidrug resistance was apparent in 58·2% of Shigella and 45·9% of Salmonella, and this phenomenon was more pronounced in S. flexneri. PMID:25586929

  2. Transcription of the procyclic acidic repetitive protein genes of Trypanosoma brucei

    International Nuclear Information System (INIS)

    The procyclic acidic repetitive protein (parp) genes of Trypanosoma brucei encode a small family of abundant surface proteins whose expression is restricted to the procyclic form of the parasite. They are found at two unlinked loci, parpA and parpB; transcription of both loci is developmentally regulated. The region of homology upstream of the A and B parp genes is only 640 base pairs long and may contain sequences responsible for transcriptional initiation and regulation. Transcription upstream of this putative promoter region is not developmentally regulated and is much less active than that of the parp genes; the polymerase responsible is inhibited by alpha-amanitin, whereas that transcribing the parp genes is not. Transcription of the parp genes is strongly stimulated by low levels of UV irradiation. The putative parp promoter, when placed upstream of the chloramphenicol acetyltransferase gene, is sufficient to cause production of chloramphenicol acetyltransferase in a T. brucei DNA transformation assay. Taken together, these results suggest that a promoter for an alpha-amanitin-resistant RNA polymerase lies less than 600 nucleotides upstream of the parp genes

  3. An efficient method of constructing homologous recom binant baculovirus with PCR-amplified fragments

    Institute of Scientific and Technical Information of China (English)

    HOU; Songwang; (侯松旺); CHEN; Xinwen; (陈新文); WANG; Hanzhong; (王汉中); HU; Zhihong; (胡志红)

    2003-01-01

    This paper describes a rapid method of constructing homologous recombinant baculovirus in E. coli with PCR-amplified fragments. By using this method, the traditional steps of constructing transfer vector are omitted. The method is based on phage λ red system which can promote the recombination between the homologous fragments with the length above 36 bp. Taking HaSNPV as an example, this paper describes the rapid recombination process by using chloramphenicol resistance gene (CmR) to replace orf135 in HaSNPV genome. A pair of primers with length of 60 bp was synthesized, in which 40 bp was homologous to the each end sequence of orf135, and the rest 20 bp was homologous to the each end sequence of CmR. By using these primers, a linear fragment containing the complete CmR gene between 40 bp of homologous arms of orf135 was generated by PCR with the plasmid pKD3 which contains CmR as the template. By transforming the linear fragment into the E. coli containing the bacterial artificial chromosome of HaSNPV and with the help of a plasmid expressing λ recombinase, the recombinants on which the homologue replacement had taken place were selected by chloramphenicol resistance. This method greatly shortens the process of constructing recombinant baculovirus since the process was performed in E. coli and does not need to construct transfer vectors. It can be further used for gene replacement and gene deletion of other large viral genomes.

  4. Construction of a System for the Stable Expression of Foreign Genes in Dunaliella salina

    Institute of Scientific and Technical Information of China (English)

    GENGDe-Gui; HANYan; WANGYi-Qin; WANGPeng; ZHANGLi-Ming; LIWen-Bin; SUNYong-Ru

    2004-01-01

    A stable transformation system for the expression of foreign genes in the unicellular greenmarine alga (Dunaliella salina Teod.) was established. Using electroporation, the alga was transformed witha plasmid containing the hepatitis B surface antigen (HBsAg) gene and the chloramphenicol acetyltransferase(CAT) gene as a selectable gene. PCR and Southern blotting analysis indicated that the HBsAEgene wasintegrated into the D. salina genome. Northern dotting analysis showed that the HBsAg gene was expressedat the mRNA level. The stable expression of HBsAg protein in transformants was confirmed by HBsAgenzyme-linked immunosorbent assay (HBsAg EUSA) and Western blotting analysis. Also, PCR and Southernblotting analyses showed that the CA Tgene was integrated into the D, salina genome, and CAT EUSAindicated that CAT protein was stably expressed in the cells. The introduced HBsAg DNA and HBsAgprotein expression were stably maintained for at least 60 generations in media devoid of chloramphenicol.This is the first report of the stable expression of foreign genes in D. salina.

  5. Characterization of Escherichia coli Isolates from an Urban Lake Receiving Water from a Wastewater Treatment Plant in Mexico City: Fecal Pollution and Antibiotic Resistance.

    Science.gov (United States)

    Rosas, Irma; Salinas, Eva; Martínez, Leticia; Cruz-Córdova, Ariadnna; González-Pedrajo, Bertha; Espinosa, Norma; Amábile-Cuevas, Carlos F

    2015-10-01

    The presence of enteric bacteria in water bodies is a cause of public health concerns, either by directly causing water- and food-borne diseases, or acting as reservoirs for antibiotic resistance determinants. Water is used for crop irrigation; and sediments and aquatic plants are used as fertilizing supplements and soil conditioners. In this work, the bacterial load of several micro-environments of the urban lake of Xochimilco, in Mexico City, was characterized. We found a differential distribution of enteric bacteria between the water column, sediment, and the rhizoplane of aquatic plants, with human fecal bacteria concentrating in the sediment, pointing to the need to assess such bacterial load for each micro-environment, for regulatory agricultural purposes, instead of only the one of the water, as is currently done. Resistance to tetracycline, ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole was common among Escherichia coli isolates, but was also differentially distributed, being again higher in sediment isolates. A distinct distribution of chloramphenicol minimum inhibitory concentrations (MIC) among these isolates suggests the presence of a local selective pressure favoring lower MICs than those of isolates from treated water. Fecal bacteria of human origin, living in water bodies along with their antibiotic resistance genes, could be much more common than typically considered, and pose a higher health risk, if assessments are only made on the water column of such bodies. PMID:26198413

  6. Bacterial Flora from Healthy Clarias gariepinus and their Antimicrobial Resistance Pattern

    Directory of Open Access Journals (Sweden)

    M.O. Efuntoye

    2012-06-01

    Full Text Available The antibiotic resistance of bacteria isolated from Clarias gariepinus from 3 farms in Ago-Iwoye, Nigeria was investigated. Morphological and biochemical characteristics of isolates revealed that majority of the bacteria belonged to the family Enterobacteriaceae. Staphylococcus aureus and Pseudomonas aeruginosa were also recovered. E. coli strains were highly resistant to ampicillin, chloramphenicol and oxytetracycline (82.4%. Majority of the Pseudomonas aeruginosa were resistant to ampicillin (63.6%, amoxycillin (54.5%, nalidixic acid (63.6% and oxytetracycline (72.7%, whereas most of the Salmonella spp. were resistant to erythromycin (85.7%, gentamycin (71.4%, amoxicillin (57.1%, chloramphenicol (57.1% and sulphamethoxazole (57.1%. All isolates were highly sensitive to ciprofloxacin, novobiocin and ofloxacin. While the presence of potentially pathogenic bacterial species as observed in the study may not present a serious human health hazard because of heat treatment accorded fish before consumption, the presence of antibiotic resistant strains should not be ignored because of the potential for horizontal gene transfer in the food chain.

  7. A set of vectors for introduction of antibiotic resistance genes by in vitro Cre-mediated recombination

    Directory of Open Access Journals (Sweden)

    Vassetzky Yegor S

    2008-12-01

    Full Text Available Abstract Background Introduction of new antibiotic resistance genes in the plasmids of interest is a frequent task in molecular cloning practice. Classical approaches involving digestion with restriction endonucleases and ligation are time-consuming. Findings We have created a set of insertion vectors (pINS carrying genes that provide resistance to various antibiotics (puromycin, blasticidin and G418 and containing a loxP site. Each vector (pINS-Puro, pINS-Blast or pINS-Neo contains either a chloramphenicol or a kanamycin resistance gene and is unable to replicate in most E. coli strains as it contains a conditional R6Kγ replication origin. Introduction of the antibiotic resistance genes into the vector of interest is achieved by Cre-mediated recombination between the replication-incompetent pINS and a replication-competent target vector. The recombination mix is then transformed into E. coli and selected by the resistance marker (kanamycin or chloramphenicol present in pINS, which allows to recover the recombinant plasmids with 100% efficiency. Conclusion Here we propose a simple strategy that allows to introduce various antibiotic-resistance genes into any plasmid containing a replication origin, an ampicillin resistance gene and a loxP site.

  8. Variability of the tandem repeat region of the Escherichia coli tolA gene.

    Science.gov (United States)

    Zhou, Kai; Vanoirbeek, Kristof; Aertsen, Abram; Michiels, Chris W

    2012-06-01

    An intragenic tandem repeat (TR) region has been previously reported in the tolA gene of Escherichia coli. In silico analysis of 123 E. coli tolA sequences from Genbank and PCR analysis of the tolA TR region from 111 additional E. coli strains revealed that this TR region is highly variable. Nine different TR sizes with 8 up to 16 repeat units were found in in silico analysis and 6 of these were also found by PCR analysis. The 13-unit TR emerged as the predominant type using both approaches (47.2% and 86.5%, respectively). Remarkably, TRs in pathogenic strains appeared to be more variable than those in non-pathogens. To demonstrate the occurrence of TR variation in a clonal population, a selection system for TR deletion events was constructed by inserting the 13-unit TR region of MG1655 in frame into a plasmid-borne chloramphenicol acetyltransferase (cat) gene. The resulting cat gene no longer conferred chloramphenicol resistance unless the insert size was reduced by TR contraction. Using this system, Cm-resistant revertants with a TR contraction were recovered at a frequency of 1.1 × 10(-7), and contraction was shown to be recA-dependent and enhanced in a DNA repair-deficient mutS background. PMID:22659144

  9. Expression, purification and preliminary diffraction studies of CmlS

    International Nuclear Information System (INIS)

    CmlS from S. venezuelae is a flavin-dependent halogenase that is involved in the biosynthesis of the widely used antibiotic chloramphenicol. Here, the crystallization of CmlS and analysis of the initial diffraction data are reported. CmlS, a flavin-dependent halogenase (FDH) present in the chloramphenicol-biosynthetic pathway in Streptomyces venezuelae, directs the dichlorination of an acetyl group. The reaction mechanism of CmlS is of considerable interest as it will help to explain how the FDH family can halogenate a wide range of substrates through a common mechanism. The protein has been recombinantly expressed in Escherichia coli and purified to homogeneity. The hanging-drop vapour-diffusion method was used to produce crystals that were suitable for X-ray diffraction. Data were collected to 2.0 Å resolution. The crystal belonged to space group C2, with unit-cell parameters a = 208.1, b = 57.7, c = 59.9 Å, β = 97.5°

  10. Therapeutic concentrations of antibiotics inhibit Shiga toxin release from enterohemorrhagic E. coli O104:H4 from the 2011 German outbreak

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    Corogeanu Diana

    2012-08-01

    Full Text Available Abstract Background The shiga toxin-producing E. coli (STEC O104:H4 caused a major outbreak in Germany in spring 2011. STEC are usually susceptible to common antibiotics. However, antibiotic treatment of STEC-infected patients is not recommended because STEC may enhance production and release of shiga toxins (STX in response to antibiotics, which eventually enhances the frequency and severity of clinical symptoms, including haemolytic uraemic syndrome (HUS and fatalities. Results We characterized the response to antibiotics of STEC O104:H4 isolates from two HUS patients during the German STEC outbreak in spring 2011 in comparison to the common STEC O157:H7. Liquid cultures of STEC O157:H7 and O104:H4 were incubated with graded dilutions of the antibiotics ciprofloxacin, meropenem, fosfomycin, gentamicin, rifampicin, and chloramphenicol. At defined times of antibiotic treatment, transcriptional activation of the STX2 gene, contents of STX and STX-activity in the culture supernatants were quantified. Unlike the common serotype O157:H7, STEC O104:H4 does not release STX in response to therapeutic concentrations of ciprofloxacin, meropenem, fosfomycin, and chloramphenicol. Conclusions In future outbreaks, the response of the respective epidemiologic STEC strain to antibiotics should be rapidly characterized in order to identify antibiotics that do not enhance the release of STX. This will eventually allow clinical studies tackling the question whether antibiotic treatment impacts on the eradication of STEC, clinical course of disease, and frequency of carriers.

  11. Optimal Expression Condition of Recombinant RAP

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jie; ZHANG Hong; BI Hao; LIU Zhiguo; GUO Jianli; QU Shen

    2007-01-01

    In order to construct the expression recombinant of human receptor associated protein (RAP), optimize its expression condition and obtain the recombinant protein after expression with high efficiency, two prokaryotic expression vectors-pT7-PL and pET-28a(+) were used to construct the expression recombinant containing RAP cDNA, and the expression efficiency of two kinds of expression E. coli of BL21 strains was compared. The effect of different induction conditions on the expression of recombinant RAP was observed. After recombinant protein was purified with Ni+-nitrilotriacetic acid (Ni+-NTA) affinity chromatogram, its binding ability with microphage was observed. The results showed that two recombinant plasmids both obtained high expression of RAP. The expression levels of RAP in plasmid pT7-PL-RAP in BL21 (DE3, plysS) strain were significantly higher than in BL21 (DE3) strain. The expression of pT7-PL-RAP in the presence of chloramphenicol was higher than in the absence of chloramphenicol, and most of the inducible expressed RAP was soluble. The RAP which was purified by Ni+-NTA resin could strongly bind with the RAW264.7 cells rich in low density lipoprotein receptor (LDLR) family receptors. It was concluded that the expression condition of recombinant RAP was optimized and functional RAP was obtained, which offered a good foundation for the further production of RAP as research tool.

  12. Detection and characterization of class 1 integrons in Aeromonas spp. isolated from human diarrheic stool in Mexico.

    Science.gov (United States)

    Pérez-Valdespino, Abigail; Fernández-Rendón, Elizabeth; Curiel-Quesada, Everardo

    2009-12-01

    We determined the presence of class 1 integrons related to the acquisition of resistance to antimicrobials in Aeromonas spp. isolated from individuals with diarrhea. Species were identified as A. caviae, A. hydrophila, A. veronii and A. media using PCR-RFLP of the 16S rDNA. Selected isolates were further characterized by ERIC-PCR. Resistance to chloramphenicol, aztreonam, tetracycline, trimethoprim/sulfamethoxazole, nalidixic acid and streptomycin, among others, was determined using the Kirby-Bauer method. Integrons were detected by PCR amplification of the 5' conserved, variable, and 3' conserved regions. Sequencing of the variable regions revealed class 1 integrons with cassettes encoding resistance to trimethoprim (dfrA12, dfrA15, dfrB4), streptomycin/spectinomycin (aadA2, aadA1), oxacillin (oxa2) and chloramphenicol (catB3, cmlA4). Others had an open reading frame (orfD) or no insert at all. To our knowledge, this is the first description of the occurrence of genes cmlA4 and dfrA15 in Aeromonas class 1 integrons. Not all the integron-linked cassettes conferred their associated resistances, which suggests the inactivity of some cassettes. Most integrons were chromosomally located. The presence of class 1 integrons similar to those found in a wide variety of bacterial genera from different origins, including environmental and fish-borne Aeromonas, confirms the stability and horizontal transfer of these genetic elements. PMID:19810047

  13. Screening of promoters from rhizosphere metagenomic DNA using a promoter-trap vector and flow cytometric cell sorting.

    Science.gov (United States)

    Lee, Se Hee; Kim, Jeong Myeong; Lee, Hyo Jung; Jeon, Che Ok

    2011-02-01

    We constructed a facilitative and efficient promoter-trap vector, pCM-EGFP, for capturing and analyzing functional promoters from environmental DNA. The pCM-EGFP vector showed good chloramphenicol sensitivity and no enhanced green fluorescent protein (EGFP) gene expression. Promoter libraries were constructed for screening promoters responding to naringenin, a key molecule released from plant roots. After electroporation, E. coli transformants were incubated in LB broth containing chloramphenicol (10 μg/ml) to select against transformants with no cloned promoter. E. coli cells were sorted using flow cytometry without naringenin, and then sorted again with high fluorescence after incubation in LB broth with naringenin (1 mM) at 28 °C for 12 h. The inducible properties of approximately 400 sorted cells were evaluated, with most cells showing only strong EGFP gene expression without inducible properties. Two clones (5-4E and 15-3D) displayed naringenin inducibility, and both contained a promoter bounded by a TetR-family regulator. The regulator knock-out mutant of the 5-4E clone lost its ability to be induced by naringenin. In conclusion, the pCM-EGFP vector may be used as an efficient promoter-trap vector and a combination of the vector with flow cytometric cell sorting was demonstrated to be an useful method for screening promoters responding to specific conditions or inducers. PMID:21259288

  14. Antimicrobial resistance trends among Salmonella isolates obtained from horses in the northeastern United States (2001-2013).

    Science.gov (United States)

    Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Aprea, Victor A; Altier, Craig

    2016-05-01

    OBJECTIVE To describe the antimicrobial resistance patterns of Salmonella isolates obtained from horses in the northeastern United States and to identify trends in resistance to select antimicrobials over time. SAMPLE 462 Salmonella isolates from horses. PROCEDURES Retrospective data were collected for all Salmonella isolates obtained from equine specimens that were submitted to the Cornell University Animal Health Diagnostic Center between January 1, 2001, and December 31, 2013. Temporal trends in the prevalence of resistant Salmonella isolates were investigated for each of 13 antimicrobials by use of the Cochran-Armitage trend test. RESULTS The prevalence of resistant isolates varied among antimicrobials and ranged from 0% (imipenem) to 51.5% (chloramphenicol). During the observation period, the prevalence of resistant isolates decreased significantly for amoxicillin-clavulanic acid, ampicillin, cefazolin, cefoxitin, ceftiofur, chloramphenicol, and tetracycline and remained negligible for amikacin and enrofloxacin. Of the 337 isolates for which the susceptibility to all 13 antimicrobials was determined, 138 (40.9%) were pansusceptible and 192 (57.0%) were multidrug resistant (resistant to ≥ 3 antimicrobial classes). The most common serovar isolated was Salmonella Newport, and although the annual prevalence of that serovar decreased significantly over time, that decrease had only a minimal effect on the observed antimicrobial resistance trends. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that current antimicrobial use in horses is not promoting the emergence and dissemination of antimicrobial-resistant Salmonella strains in the region served by the laboratory. PMID:27111018

  15. Antimicrobial resistance of coagulase-negative staphylococci and lactic acid bacteria from industrially produced dairy products

    Directory of Open Access Journals (Sweden)

    Nevijo Zdolec

    2013-03-01

    Full Text Available In this research, the susceptibility to clindamycin, tetracycline, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, trimethoprim + sulphametoxazol, tobramycin, chloramphenicol, ciprofloxacin, erythromycin, penicillin and trimethoprim was tested in coagulase-negative staphylococci (n=78 and lactic acid bacteria (n=30 by means of disk diffusion test and E-test. The isolates were collected from soft and hard cheeses, butter and brine. All isolates of coagulase-negative staphylococci were susceptible to clindamycin, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, chloramphenicol and ciprofloxacin according to CLSI breakpoints. A total of 30 staphylococci isolates (38.46 % were resistant to erythromycin, 18 to penicillin (23.07 %, 4 to tetracycline (5.12 %, and one isolate to trimethoprim, tobramicin and trimethoprim + sulphametoxazol (1.28 %. Among 78 tested staphylococci, 35 of them were resistant to at least one antimicrobial substance (44.87 %. The rate of resistant isolates of different soft cheese types ranged from 22 to 70 %, while resistant staphylococci were absent in hard cheese and brine. The growth of lactic acid bacteria was not influenced by trimethoprim + sulphametoxazol (n=29, vancomycin (n=29, trimethoprim (n=28, amikacin (n=10 and tobramycin (n=10. The results show that significant part of apathogenic microbiota in different dairy products is phenotypically resistant to antimicrobial agents.

  16. Antibiotic susceptibility of body surface and gut micro flora of two aquatic leech species (Hirudinaria manillensis and Hirudinaria javanica) in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Parimannan Sivachandran; Kasi Marimuthu; Manickam Ravichandran; Jesu Arockiaraj

    2013-01-01

    Objective: To elucidate the antibiotic susceptibility of body surface and gut associated microflora of two local aquatic leech species Hirudinaria manillensis and Hirudinaria javanica.Methods:Four commercially available antibiotics (doxycycline, chloramphenicol, tetracycline and ciprofloxacin) were used in this study. A total of 13 isolated gut and two surface micro flora from Hirudinaria manillensis and two gut and two surface micro flora from Hirudinaria javanica were tested for their antibiotic susceptibility. Results: Based on the susceptibility, it was observed that all the isolated bacteria were found to be susceptible to at least three of the antibiotics except Microbacterium resistens, Serratiamarcescens and Morganella morganii. This study also found that the bacterial species Bacillus fusiformis has displayed resistance against tetracycline and Tsukamurella inchonensis against chloramphenicol.Conclusions:Among all the antibiotics tested, ciprofloxacin was found to be the best bactericidal agent. The immersion of leeches in ciprofloxacin before the application to the patient may be beneficial to prevent invasive infection of the patient. Further study is needed to sterilize the live leech by immersion/oral mode of administration for the tested antibiotics.

  17. Influence of a uvrD mutation on survival and repair of X-irradiated Escherichia coli K-12 cells

    International Nuclear Information System (INIS)

    The presence of a uvrD mutation increased the X-ray sensitivities of E.coli wild-type and polA strains, but had no effect on the sensitivities of recA and recB strains, and little effect on a lexA strain. Incubation of irradiated cells in medium containing 2,4-dinitrophenol or chloramphenicol decreased the survival of wild-type and uvrD cells, but had no effect on the survival of recA, recB and lexA strains. Alkaline sucrose gradient sedimentation studies indicated that the uvrD strain is deficient in the growth-medium-dependent (Type III) repair of DNA single-strand breaks. These results indicate that the uvrD mutation inhibits certain rec+lex+-dependent repair processes, including the growth-medium-dependent (Type III) repair of X-ray-induced DNA single-strand breaks, but does not inhibit other rec+lex+-dependent processes that are sensitive to 2,4-dinitrophenol and chloramphenicol. (author)

  18. Methicillin-Resistant Staphylococcus aureus Keratitis after Descemet's Stripping Automated Endothelial Keratoplasty

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    Tatsuro Miyamoto

    2013-11-01

    Full Text Available Purpose: We report a case of methicillin-resistant Staphylococcus aureus (MRSA keratitis after Descemet's stripping automated endothelial keratoplasty (DSAEK. Case Report: An 87-year-old woman who had undergone a DSAEK 4 months previously was referred to Tokushima University Hospital with a diagnosis of infectious keratitis after DSAEK. A white abscess and infiltration in the inferior cornea of the right eye were observed. We started an empiric therapy using topical levofloxacin and chloramphenicol on the basis of the microscopic findings of the corneal scraping concurrently with cultivation of the cornea. Results: A strain of MRSA was isolated from the corneal sample. Although the strain was susceptible to chloramphenicol, it was resistant to quinolone. The keratitis improved rapidly due to empiric therapy, and topical steroids could be resumed 6 days after initiation of the empiric therapy. Conclusions: To our knowledge, this is the first case of MRSA keratitis, and the second case of bacterial keratitis, after DSAEK. MRSA keratitis can occur following uneventful DSAEK. The empiric therapy on the basis of results from a light microscopic examination of a Gram-stained corneal scraping and restarting topical steroids in the early stages of medication contributed to the good clinical course of this case.

  19. Multiclass determination and confirmation of antibiotic residues in honey using LC-MS/MS.

    Science.gov (United States)

    Lopez, Mayda I; Pettis, Jeffery S; Smith, I Barton; Chu, Pak-Sin

    2008-03-12

    A multiclass method has been developed for the determination and confirmation in honey of tetracyclines (chlortetracycline, doxycycline, oxytetracycline, and tetracycline), fluoroquinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, and sarafloxacin), macrolides (tylosin), lincosamides (lincomycin), aminoglycosides (streptomycin), sulfonamides (sulfathiazole), phenicols (chloramphenicol), and fumagillin residues using liquid chromatography tandem mass spectrometry (LC-MS/MS). Erythromycin (a macrolide) and monensin (an ionophore) can be detected and confirmed but not quantitated. Honey samples (approximately 2 g) are dissolved in 10 mL of water and centrifuged. An aliquot of the supernatant is used to determine streptomycin. The remaining supernatant is filtered through a fine-mesh nylon fabric and cleaned up by solid phase extraction. After solvent evaporation and sample reconstitution, 15 antibiotics are assayed by LC-MS/MS using electrospray ionization (ESI) in positive ion mode. Afterward, chloramphenicol is assayed using ESI in negative ion mode. The method has been validated at the low part per billion levels for most of the drugs with accuracies between 65 and 104% and coefficients of variation less than 17%. The evaluation of matrix effects caused by honey of different floral origin is presented. PMID:18257525

  20. Role of porins for uptake of antibiotics by Mycobacterium smegmatis.

    Science.gov (United States)

    Danilchanka, Olga; Pavlenok, Mikhail; Niederweis, Michael

    2008-09-01

    The outer membrane of mycobacteria presents an effective permeability barrier for many antibiotics. Transport pathways across this membrane are unknown for most drugs. Here, we examined which antibiotics utilize the porin pathway across the outer membrane of the model organism Mycobacterium smegmatis. Deletion of the porins MspA and MspC drastically increased the resistance of M. smegmatis ML10 to beta-lactam antibiotics, while its beta-lactamase activity remained unchanged. These results are consistent with the ninefold-reduced outer membrane permeability of the M. smegmatis porin mutants for cephaloridine and strongly indicate that beta-lactam antibiotics rely on the porin pathway. The porin mutant ML10 accumulated less chloramphenicol and norfloxacin and was less susceptible to these antibiotics than wild-type M. smegmatis. These results demonstrated that small and hydrophilic antibiotics use the Msp porins for entering the cell. In contrast to norfloxacin, the hydrophobic moxifloxacin was 32-fold more effective in inhibiting the growth of M. smegmatis, presumably because it was able to diffuse through the lipid membrane. Structural models indicated that erythromycin, kanamycin, and vancomycin are too large to move through the MspA channel. This study presents the first experimental evidence that hydrophilic fluoroquinolones and chloramphenicol diffuse through porins in mycobacteria. Thus, mutations resulting in less efficient porins or lower porin expression levels are likely to represent a mechanism for the opportunistic pathogens M. avium, M. chelonae, and M. fortuitum, which have Msp-like porins, to acquire resistance to fluoroquinolones. PMID:18559650

  1. ANTIBIOTIC RESISTANCE IN LACTIC ACID BACTERIA ISOLATED FROM FERMENTED DAIRY PRODUCTS AND BOZA

    Directory of Open Access Journals (Sweden)

    Gamze Başbülbül

    2015-06-01

    Full Text Available In this study, the resistance of 83 strains of lactic acid bacteria isolated from Turkish cheese, yogurt, kefir and boza samples to 6 antibiotics (gentamicin, tetracycline, chloramphenicol, erythromycin, vancomycin and ciprofloxacin was evaluated. The 83 isolates were identified by 16S rRNA gene sequencing and according to BLAST comparisons with sequences in the data banks, those strains showing the highest similarities with the isolates were Enterococcus faecium (10, Lactococcus lactis subsp. Lactis (10, Lactobacillus fermentum (6, Lactobacillus plantarum (6, Lactobacillus coryniformis (7, Lactobacillus casei (13, Leuconostoc mesenteroides (14, Pediococcus pentosaceus (10, Weisella confusa (7. Antimicrobial resistance of strains to 6 antibiotics was determined using the agar dilution method. The antibiotic resistance among all the isolates was detected against chloramphenicol (31,3 % of the isolates, tetracycline (30,1 %, erythromycin (2,4 %, ciprofloxacin (2,41%, vancomycin (73,5 %, intrinsic resistance. Overall 19,3 % of the isolates showed resistance against multiple antibiotics. Antibiotic resistance genes were studied by PCR and the following genes were detected; tet(M gene in Lactobacillus fermentum (1, Lactobacillus plantarum (1, Pediococcus pentosaceus (5, Enterococcus faecium (2, Weisella confusa (4 and the vancomycin resistance gene van(A in one Weisella confusa strain.

  2. Serologic test systems development. Progress report, October 1, 1978-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Seawright, G.L.; Sanders, W.M.; Hollstein, U.; Butler, J.E.; Mills, K.W.; Despommier, D.D.; Zimmerman, W.J.; Martinez, E.; Hindman, K.R.; Payne, R.J.

    1980-12-01

    Work has continued on the development and automation of enzyme immunoassays (EIA) for detecting diseases and toxic agents in food animals. Further evaluations were made of the Technicon Autoanalyzer II(AAII) for conducting totally automated EIAs. The problems investigated were machine carryover and assay variation. Modifications greatly reduced or eliminated carryover and produced acceptable levels of test variation. The EIA for swine trichinosis was significantly improved by the use of a new, partially purified antigen preparation. The result was improved detection of early seroconversions and reduced probability for false negatives and false positives. The amplified EIA was adapted as a diagnostic test for bovine brucellosis and studies were initiated for differentiating vaccinated and infected animals. Preliminary data indicate that the IgG/sub 1/ response may be diagnostic but further studies are necessary. Development of the EIA for detecting low molecular weight contaminants and residues in food products was also initiated. Compounds studied were the antibiotics chloramphenicol, tetracycline, and gentamicin; the mycotoxin, aflatoxin, and the shale oil toxin, 2-aminofluorene. Results indicate that chloramphenicol nonspecifically binds to antibody and interferes with antibody activity. Thus, the test is not yet satisfactory. Initial attempts to automate the gentamicin test were unsuccessful because of machine carryover but modifications of the AAII have produced encouraging preliminary data. Work is continuing on the development of EIAs for all of the compounds mentioned above. (ERB)

  3. Effects of {gamma}-radiation on the fungus Alternaria alternata in artificially inoculated cereal samples

    Energy Technology Data Exchange (ETDEWEB)

    Braghini, R. [Departamento de Microbiologia, Instituto de Ciencias Biomedicas II, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1374, CEP 05508-900 Sao Paulo (Brazil)], E-mail: raquelbraghini@yahoo.com.br; Pozzi, C.R. [Instituto de Zootecnia, Rua Heitor Penteado 56, CEP 13460-000, Nova Odessa, Sao Paulo (Brazil); Aquino, S. [Instituto Adolfo Lutz, Av. Dr. Arnaldo, 355 , CEP 01246-902, Sao Paulo (Brazil); Rocha, L.O.; Correa, B. [Departamento de Microbiologia, Instituto de Ciencias Biomedicas II, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1374, CEP 05508-900 Sao Paulo (Brazil)

    2009-09-15

    The objective of this study was to evaluate the effects of different {gamma}-radiation doses on the growth of Alternaria alternata in artificially inoculated cereal samples. Seeds and grains were divided into four groups: Control Group (not irradiated), and Groups 1, 2 and 3, inoculated with an A. alternata spore suspension (1x10{sup 6} spores/mL) and exposed to 2, 5 and 10 kGy, respectively. Serial dilutions of the samples were prepared and seeded on DRBC (dichloran rose bengal chloramphenicol agar) and DCMA (dichloran chloramphenicol malt extract agar) media, after which the number of colony-forming units per gram was determined in each group. In addition, fungal morphology after irradiation was analyzed by scanning electron microscopy (SEM). The results showed that ionizing radiation at a dose of 5 kGy was effective in reducing the growth of A. alternata. However, a dose of 10 kGy was necessary to inhibit fungal growth completely. SEM made it possible to visualize structural alterations induced by the different {gamma}-radiation doses used.

  4. Oxidative stress/reactive metabolite gene expression signature in rat liver detects idiosyncratic hepatotoxicants.

    Science.gov (United States)

    Leone, Angelique; Nie, Alex; Brandon Parker, J; Sawant, Sharmilee; Piechta, Leigh-Anne; Kelley, Michael F; Mark Kao, L; Jim Proctor, S; Verheyen, Geert; Johnson, Mark D; Lord, Peter G; McMillian, Michael K

    2014-03-15

    Previously we reported a gene expression signature in rat liver for detecting a specific type of oxidative stress (OS) related to reactive metabolites (RM). High doses of the drugs disulfiram, ethinyl estradiol and nimesulide were used with another dozen paradigm OS/RM compounds, and three other drugs flutamide, phenacetin and sulindac were identified by this signature. In a second study, antiepileptic drugs were compared for covalent binding and their effects on OS/RM; felbamate, carbamazepine, and phenobarbital produced robust OS/RM gene expression. In the present study, liver RNA samples from drug-treated rats from more recent experiments were examined for statistical fit to the OS/RM signature. Of all 97 drugs examined, in addition to the nine drugs noted above, 19 more were identified as OS/RM-producing compounds-chlorpromazine, clozapine, cyproterone acetate, dantrolene, dipyridamole, glibenclamide, isoniazid, ketoconazole, methapyrilene, naltrexone, nifedipine, sulfamethoxazole, tamoxifen, coumarin, ritonavir, amitriptyline, valproic acid, enalapril, and chloramphenicol. Importantly, all of the OS/RM drugs listed above have been linked to idiosyncratic hepatotoxicity, excepting chloramphenicol, which does not have a package label for hepatotoxicity, but does have a black box warning for idiosyncratic bone marrow suppression. Most of these drugs are not acutely toxic in the rat. The OS/RM signature should be useful to avoid idiosyncratic hepatotoxicity of drug candidates. PMID:24486436

  5. Identification and antimicrobial susceptibility of bacteria isolated from corneal ulcers of dogs Identificação e susceptibilidade antimicrobiana de bactérias isoladas de úlceras de córnea em cães

    Directory of Open Access Journals (Sweden)

    M.R. Prado

    2006-12-01

    Full Text Available A total of 22 clinical specimens were obtained from 19 dogs with corneal ulcer (16 unilateral and three bilateral for isolation and antimicrobial susceptibility evaluation of the isolated bacteria. Bacterial growth was observed in 100% of the samples (n=22. Staphylococcus intermedius was the predominant species (35.5%, followed by Corynebacterium xerosis (19.3%. Gentamicin, ciprofloxacin, chloramphenicol and tobramycin had a high efficacy against all of the isolated bacteria. The results evidenced that 80.7% of the isolates were Gram positive cocci and Gram positive bacilli, and that those microorganisms were sensitive to gentamicin, ciprofloxacin, chloramphenicol and tobramycin.Utilizaram-se 22 amostras de material, obtidas de 19 cães com úlcera de córnea, sendo 16 unilaterais e três bilaterais, para isolamento e avaliação da susceptibilidade antimicrobiana das bactérias isoladas. Observou-se crescimento bacteriano em 100% das amostras (n=22. A espécie predominante foi Staphylococcus intermedius (35,5% seguido de Corynebacterium xerosis (19,3%. Gentamicina, ciprofloxacina, cloranfenicol e tobramicina apresentaram alta eficácia contra todas as bactérias isoladas. Os resultados evidenciam que 80,7% dos isolados foram cocos e bacilos Gram positivos e que estes microrganismos foram sensíveis à gentamicina, ciprofloxacina, cloranfenicol e tobramicina.

  6. Analysis of plasmid DNA synthesis by double tracer method

    International Nuclear Information System (INIS)

    An Escherichia coli strain, CR34, harboring both pSC101 and ColEl-amp plasmids was exposed to media containing rifampicin (100 μg/ml) and/or chloramphenicol (180 μg/ml) and the cells were labeled for 20 min with 3H-thymine at 3,25 and 50 min after exposure to drug(s). The plasmid DNA synthesis was assayed by DNA-DNA hybridization with 14C-labeled pSC134 DNA as internal marker. In the presence of rifampicin, the replication of pSC 101 was from 57 to 104% that in its absence, and that of ColEl-amp was from 17 to 26%. The DNA replication of pSC101 after addition of chloramphenicol was reduced to 35 to 75%, and that of ColEl-amp was reduced to 39% and then restored to 92%. This restoration was not observed in the presence of rifampicin. (author)

  7. In vitro and in silico Approaches to the Identification of New Compounds with Antibacterial Profile

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    Carlos R. Rodrigues

    2013-06-01

    Full Text Available The emergence of multidrug-resistant bacterial strains is a world problem that increases the need for new and more effective antimicrobials. On that purpose, derivatives of cyclic systems may serve as new leads for discovering new active molecules. In this work we evaluated the antibacterial profile of 243 molecules derived from the systems thienopyridine, pyrazolopiridine, quinolone, chalcone, hydrazone and lapachone against Gram-positive and Gram-negative susceptible and multiresistant strains also comparing them with antibiotics of clinical use. Our results showed that among the 243 molecules tested, only eight derivatives were active with promissing MIC values (2-64mg/mL. Our theoretical in silico analysis showed that all active compounds fulfilled Lipinski rule of five (molecular weight = 344.37–409.24, clogP = 3.15–4.11, nHBA = 6–7, and nHBD = 2, similarly to commercial drugs as well as presented better druglikeness values (from -3.68 to 0.12 than chloramphenicol (-4.61 and linezolid (-4.08. Most of the active derivatives presented a low in silico toxicity risk profile, similar to oxacillin, ampicillin, and penicillin G, and even lower than that observed for chloramphenicol and linezolid. Theoretically HOMO and the electrostatic protential distribution may be contributing for this safer profile. This study used computacional tools and may help to deal with an important world health problem.

  8. SYNERGISTIC EFFECT OF ANTIBIOTICS AND OXYTOCIN IN THE TREATMENT OF ENDOMETRITIS IN MARES

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    M. Ahmad, N. Ahmad. M.K. Mansoor and H.A. Samad

    2001-09-01

    Full Text Available The present study was designed to investigate the effect of oxytocin with or without intrauterine antibiotics infusion, on conception rates in 150 endometritic mares. Uterine swabs were collected from each mare and processed for antibiotic sensitivity tests. Samples from 135 mares showing bacterial growth and antibiotic sensitivity were divided into following groups: Control given oxytocin only, Gentamicin or gentamicin + Oxytocin, Chloramphenicol or Chloramphenicol + Oxytocin, Streptopenicillin + Kanamycin or Streptopenicillin + Kanamycin + Oxytocin and Norfloxacin or Norfloxacin + Oxytocin. After treatment for five days one heat was missed and on second heat mares were bred through natural. mating and examined for pregnancy at least 60 days after service. The overall conception rate in mares of groups treated using antibiotics without oxytocin (62.22% was significantly higher (P<0.05 as compared to 40.00% in the control group. However, conception rates in mares of former groups did not differ from one , another. Similarly. overall conception rate in mares treated using antibiotic + oxytocin combination (82.62% was significantly higher (P<0.05 than overall conception rate in mares treated with antibiotics alone (62.22% or control (40.00%. It was concluded that oxytocin alongwith some suitable antibiotic (s may be used for the treatment of endometritis and improvement of conception rates in endometritic mares

  9. Antibiotic susceptibility of body surface and gut micro flora of two aquatic leech species (Hirudinaria manillensis and Hirudinaria javanica in Malaysia

    Directory of Open Access Journals (Sweden)

    Parimannan Sivachandran

    2013-08-01

    Full Text Available Objective: To elucidate the antibiotic susceptibility of body surface and gut associated microflora of two local aquatic leech species Hirudinaria manillensis and Hirudinaria javanica. Methods: Four commercially available antibiotics (doxycycline, chloramphenicol, tetracycline and ciprofloxacin were used in this study. A total of 13 isolated gut and two surface micro flora from Hirudinaria manillensis and two gut and two surface micro flora from Hirudinaria javanica were tested for their antibiotic susceptibility. Results: Based on the susceptibility, it was observed that all the isolated bacteria were found to be susceptible to at least three of the antibiotics except Microbacterium resistens, Serratia marcescens and Morganella morganii. This study also found that the bacterial species Bacillus fusiformis has displayed resistance against tetracycline and Tsukamurella inchonensis against chloramphenicol. Conclusions: Among all the antibiotics tested, ciprofloxacin was found to be the best bactericidal agent. The immersion of leeches in ciprofloxacin before the application to the patient may be beneficial to prevent invasive infection of the patient. Further study is needed to sterilize the live leech by immersion/oral mode of administration for the tested antibiotics.

  10. A SAM-dependent methyltransferase cotranscribed with arsenate reductase alters resistance to peptidyl transferase center-binding antibiotics in Azospirillum brasilense Sp7.

    Science.gov (United States)

    Singh, Sudhir; Singh, Chhaya; Tripathi, Anil Kumar

    2014-05-01

    The genome of Azospirillum brasilense harbors a gene encoding S-adenosylmethionine-dependent methyltransferase, which is located downstream of an arsenate reductase gene. Both genes are cotranscribed and translationally coupled. When they were cloned and expressed individually in an arsenate-sensitive strain of Escherichia coli, arsenate reductase conferred tolerance to arsenate; however, methyltransferase failed to do so. Sequence analysis revealed that methyltransferase was more closely related to a PrmB-type N5-glutamine methyltransferase than to the arsenate detoxifying methyltransferase ArsM. Insertional inactivation of prmB gene in A. brasilense resulted in an increased sensitivity to chloramphenicol and resistance to tiamulin and clindamycin, which are known to bind at the peptidyl transferase center (PTC) in the ribosome. These observations suggested that the inability of prmB:km mutant to methylate L3 protein might alter hydrophobicity in the antibiotic-binding pocket of the PTC, which might affect the binding of chloramphenicol, clindamycin, and tiamulin differentially. This is the first report showing the role of PrmB-type N5-glutamine methyltransferases in conferring resistance to tiamulin and clindamycin in any bacterium. PMID:24573606

  11. Isolation and characterization of hemolytic bacteria Fish disc and Neon RainbowIsolamento e caracterização de bactérias hemolíticas de Acará Disco e Neon Arco-Íris

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    José Luiz Pedreira Mouriño

    2012-05-01

    Full Text Available The aim of this study was to isolate, identify and determine the ability of potential pathogenic bacteria hemolytic mite Disco (Symphysodon discus and Neon Rainbow (Melanotaenia praecox, and define which of the antibiotic Trimethoprim, Florfenicol, Chloramphenicol, Norfloxacin, Erythromycin, Bacitracin, Enrofloxacin, Tetracycline, and Furazolidone Clindamycin has better inhibitory effect in vitro, and determine the minimum inhibitory concentration (MIC for Chloramphenicol, Norfloxacin, Erythromycin and Enrofloxacin. In an outbreak of ornamental fish deaths were isolated nine strains of Gram negative, hemolytic where 3 were identified, two as Vibrio cholerae and one as Citrobacter braakii. With these strains were performed antibiogram and was determined the minimum inhibitory concentration at two different temperatures (22 and 30 ° C. Antibiotics Enrofloxacin, Norfloxacin, florfenicol, chloramphenicol and trimethoprim showed the best results in vitro inhibition against the Vibrio cholerae, and Citrobacter braakii. The MIC increased in 30 ° C for erythromycin and enrofloxacin against pathogens, while for Florfenicol and norfloxacin the MIC was not influenced by temperature.O objetivo deste estudo foi isolar, identificar e determinar a capacidade hemolítica de possíveis bactérias patogênicas do Acará Disco (Symphysodon discus e Neon Arco-íris (Melanotaenia praecox, e definir qual o antibiótico entre Trimetoprim, Florfenicol, Cloranfenicol, Norfloxacina, Eritromicina, Bacitracina, Enrofloxacina, Tetraciclina, Furazolidona e Clindamicina possui melhor efeito inibitório in vitro, e determinar a concentração inibitória mínima (MIC para Cloranfenicol, Norfloxacina, Eritromicina e Enrofloxacina. Em um surto de mortalidade de peixes ornamentais foram isoladas nove cepas de bactérias Gram negativas, onde três hemolíticas foram identificadas, duas como Vibrio cholerae e uma como Citrobacter braakii. Com estas foram realizados antibiogramas

  12. TEM-1 AND ROB-1 PRESENCE AND ANTIMICROBIAL RESISTANCE IN HAEMOPHILUS INFLUENZAE STRAINS, ISTANBUL, TURKEY.

    Science.gov (United States)

    Kuvat, Nuray; Nazik, Hasan; Berkiten, Rahmiye; Öngen, Betigül

    2015-03-01

    Resistance of 235 Haemophilus influenzae clinical isolates from Istanbul Medical Faculty Hospital, Turkey were determined against 19 antibiotics by disc diffusion method, and minimum inhibitory concentrations (MICs) of those found resistant to ampicillin, cefuroxim, chloramphenicol and meropenem were measured using E-test. Ampicillin-resistant isolates producing beta-lactamase as demonstrated by a nitrocefin assay were analyzed for the presence of TEM-1 and ROB-1 genes by PCR. Eleven percent of the isolates were resistant to ampicillin (10 µg/ml), of which 73% were beta-lactamase positive and carried TEM-1 gene, but none were positive for ROB-1 gene. All isolates susceptible to amoxicillin-clavulanate (20/10 µg/ml), azithromycin (15 µg/ml), aztreonam (30 µg/ml), cefotaxime (30 µg/ml), ceftriaxone (30 µg/ml), ciprofloxacin (5 µg/ml), levofloxacin (5 µg/ml), and telithromycin (15 µg/ml) but 24%, 15%, 4%, 4%, 2%, 1%, 1%, 0.5%, 0.5% and 0.5% were resistant to trimethoprim-sulfamethoxazole (1.25/23.75 µg/ml), tetracycline (30 µg/ml), cefaclor (30 µg/ml), clarithromycin (15 µg/ml), cefuroxime (30 µg/ml), meropenem (10 µg/ml), chloramphenicol (30 µg/ml), ampicillin-sulbactam (10/10 µg/ml), nalidixic acid (30 µg/ml), and fosfomycin (30 µg/ml), respectively. MIC values of three cefuroxime-resistant isolates was 24, 48 and > 256 µg/ml, respectively; of two meropenem-resistant strains > 256 µg/ml; and of two chloramphenicol-susceptible isolates (by disc diffusion method) 6 µg/ml (considered as intermediate susceptible). Multiple- antibiotics resistance was detected in 15% of the strains, with resistance to 2, 3, 4, 5 and 6 antibiotics in 8.5%, 4%, 2%, 0.5% and 0.5% of the isolates, respectively. By identifying beta-lactamase-negative ampicillin-resistant H. influenzae, empirical therapy with beta-lactam/beta-lactamase inhibitor combinations and second generation cephalosporins would be inappropriate for such patients (approximately 3%). Our findings will

  13. In vitro activities of nisin and nisin derivatives alone and in combination with antibiotics against Staphylococcus biofilms

    Directory of Open Access Journals (Sweden)

    Des eField

    2016-04-01

    Full Text Available The development and spread of pathogenic bacteria that are resistant to the existing catalogue of antibiotics is a major public health threat. Biofilms are complex, sessile communities of bacteria embedded in an organic polymer matrix which serve to further enhance antimicrobial resistance. Consequently, novel compounds and innovative methods are urgently required to arrest the proliferation of drug-resistant infections in both nosocomial and community environments. Accordingly, it has been suggested that antimicrobial peptides could be used as novel natural inhibitors that can be used in formulations with synergistically-acting antibiotics. Nisin is a member of the lantibiotic family of antimicrobial peptides that exhibit potent antibacterial activity against many Gram-positive bacteria. Recently we have used bioengineering strategies to enhance the activity of nisin against several high profile targets, including multi-drug resistant clinical pathogens such as methicillin-resistant Staphylococcus aureus (MRSA, vancomycin-resistant enterococci (VRE, staphylococci and streptococci associated with bovine mastitis. We have also identified nisin derivatives with an enhanced ability to impair biofilm formation and to reduce the density of established biofilms of methicillin resistant Staphylococcus pseudintermedius (MRSP. The present study was aimed at evaluating the potential of nisin and nisin derivatives to increase the efficacy of conventional antibiotics and to assess the possibility of killing and/or eradicating biofilm-associated cells of a variety of staphylococcal targets. Growth curve-based comparisons established that combinations of derivatives nisin V + penicillin or nisin I4V + chloramphenicol had an enhanced inhibitory effect against S. aureus SA113 and S. pseudintermedius DSM21284 respectively compared to the equivalent nisin A + antibiotic combinations or when each antimicrobial was administered alone. Furthermore, the metabolic

  14. Antibacterial quality of some antibiotics available in five administrative areas along the national borders of Tanzania

    Directory of Open Access Journals (Sweden)

    Mwambete KD

    2014-12-01

    Full Text Available Kennedy D Mwambete Department of Pharmaceutical Microbiology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania Introduction: In developing countries like Tanzania, bacterial infections are becoming increasingly difficult to treat with available antibiotics. Poor quality antibiotics jeopardize the management of bacterial infections and contribute to the development of antibiotic resistance. Poor storage and harsh tropical climatic conditions accelerate deterioration of antibiotics. Hence, this study investigated the antibacterial effect of antibiotics available in five administrative regions along the national borders of Tanzania. Materials and methods: A cross-sectional study involved the purchase of antibiotics from the Mwanza, Arusha, Kilimanjaro, Mbeya, and Kagera administrative regions. The Kirby–Bauer disk diffusion method was employed to assess antibacterial effects of the antibiotics against Salmonella typhi, Klebsiella spp., Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Inhibition zones (IZ were determined as previously described. Analysis of variance was used to examine the IZ measured using test antibiotics to their respective control antibiotics; differences were considered significant at P<0.05. Results: Seventy-six antibiotic samples from 22 manufacturers were tested. Six antibiotic samples were from anonymous manufacturers and 29 antibiotic samples had no manufacturing or expiration dates. Different samples of the same antibiotics produced variable results. IZ measured using different samples of ampicillin (AMP and ciprofloxacin and their control antibiotics revealed significant differences when tested against S. typhi (P<0.05. Samples of tetracycline and chloramphenicol resulted in IZ comparable to their controls against S. typhi. All samples of AMP yielded comparable IZ on Klebsiella spp., whereas samples of chloramphenicol and tetracycline exerted IZ against P. aeruginosa that

  15. Preliminary Study on Effect of Radiative Degradation on Quality Safety of Honey%辐照降解对蜂蜜安全品质影响的初步研究

    Institute of Scientific and Technical Information of China (English)

    黄志勇; 徐宏; 黄燕萍

    2011-01-01

    The honey, locally produced in Jiangxi province, was treated with 60Co -γ ray at three irradiative doses (4,6 and 8 kGy). The results showed that after radiation treatment, the honey fitted the national hygienic standard and the requirement of corporative control, because the colonies of coliform bacteria, fungi and microzyme were not detected within the treated honey samples. The sensory parameters of the treated honey samples, including appearance, color, luster, odor and taste, were not affected, and had no significant differences as compared with the control. The physical and chemical nutritional indexes of the radiated honey samples, such as moisture, acidity, amylase, fructose, glucose, sucrose content and so on, were not significantly affected either. The contents of residual chloramphenicol and hydromethyl furaldehyde were decreased with the increase of irradiative dose, and chloramphenicol was not detected at the irradiative dose of 8 kCy. This study suggested that the irradiation could not only improve the hygienic indexes of honey , but also effectively reduce the contents of residual chloramphenicol and hydromethyl furaldehyde in honey.%选用江西本地生产的蜂蜜,采用4.0、6.0、8.0 kGy 3种剂量进行60Co-γ射线辐照处理,试验表明:经3种剂量辐照处理后,蜂蜜的菌落总数、大肠菌群、霉菌及酵母菌均未检出,符合国家卫生标准和企控要求;蜂蜜的外观、色泽、气味、口感等感官指标变化不大,与对照比较均无明显差异;蜂蜜的水分、酸度、淀粉酶值、果糖、葡萄糖、蔗糖等理化营养指标均无明显变化;蜂蜜中残留的氯霉素及羟甲基糠醛的含量随辐照剂量的升高而降低,在剂量为8.0 kGy时,蜂蜜中未检出氯霉素.

  16. In vitro and In vivo Anti-Microbial Effects of Nigella sativa Linn. Seed Extracts Against Clinical Isolates from Skin Wound Infections

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    Mariam A. Abu-Al-Basalc

    2009-01-01

    Full Text Available Problem statement: The developing microbial resistance to the existing anti-microbial agents has become a real challenge and a serious problem facing patients suffering from skin infections. Seeds of Nigella sativa have been used for a long time in folk medicine for the treatment of such infections. Production of new potent agents is urgently needed, especially for hospitals and health centers. Therefore, the anti-microbial effect of aqueous, diethyl ether, chloroform and petroleum ether extracts of the seeds against four standard microbial strains and seven clinical isolates from patients with skin wound infections were investigated. Approach: The in vitro anti-microbial effect of the extracts at a concentration of 20% on standard strains and clinical isolates was assessed and compared with standard drugs, chloramphenicol and amphotericin B using agar well diffusion assay. The in vivo anti-bacterial effect of petroleum ether extract was studied in male BALB/c mice infected subcutaneously with S. aureus (ATCC 25923 or a clinical isolate (0.1 mL from 109 colony forming units mL-1 suspension and immediately treated at the infected site by subcutaneous injection of 0.1 mL of pure extract (fixed oil or chloramphenicol or normal saline. Counts of viable bacteria present in the skin area corresponding to the infected site were determined, after 24 and 48 h of infection and treatment. Results: The aqueous extract did not show any inhibitory effect against all the tested microorganisms. The diethyl ether and chloroform extracts indicated significant inhibitory effect only against Gram-positive bacteria. However, petroleum ether extract was proved to be the most powerful one against these bacteria and also against other clinical isolates like one Gram-negative bacterium (Klebsiella pneumonia and the yeast (Candida albicans. Moreover, the extract revealed a superior effect over the standard drug, chloramphenicol, on the clearance of subcutaneous

  17. Second research coordination meeting of the coordinated research project 'Development of strategies for the effective monitoring of veterinary drug residues in livestock and livestock products in developing countries' (D3.20.22)

    International Nuclear Information System (INIS)

    The second RCM under this CRP was held in Pretoria, South Africa, 3 - 7 November 2003. Eleven of the twelve research contract holders, three research agreement holders and one technical contract holder attended the RCM. The three research agreement holders gave presentations on relevant aspects of veterinary drug residues analysis. The increasingly important role of bioassay techniques such as reporter gene assays for the direct screening of the effects of hormonal and other residues in animal cells and the future role of such assays to complement existing instrumental techniques was highlighted. The technical contract holder and research contract holders reviewed the results of the research and method development performed under the first phase of the CRP. Considerable progress has been made in many aspects of the overall work plan. Several commercial immunoassay methods have been critically evaluated. The main problems identified with these kits were the instability of reagents, notably the enzyme conjugates, resulting in poor performance, and the need for better sample preparation protocols applicable to a wider range of matrices. Work plans have been agreed with several laboratories to attempt to address these problems. Good progress has been made in several laboratories working on the development of in-house ELISA methods for chloramphenicol residues. The laboratories involved have produced and characterized antisera in various species and these will be used with reagents produced by technical contract holders to elaborate assay protocols. Further investigation into aspects such as reagent stability, antibody maturation and assay development using various assay formats is planned. A full set of reagents and protocols for their optimisation in a 125I radioimmunoassay (RIA) for chloramphenicol have been developed by the technical contract holders and transferred to a research contract holder for further method development. However, this researcher was unable to

  18. In Vitro Activities of Nisin and Nisin Derivatives Alone and In Combination with Antibiotics against Staphylococcus Biofilms.

    Science.gov (United States)

    Field, Des; O' Connor, Rory; Cotter, Paul D; Ross, R Paul; Hill, Colin

    2016-01-01

    The development and spread of pathogenic bacteria that are resistant to the existing catalog of antibiotics is a major public health threat. Biofilms are complex, sessile communities of bacteria embedded in an organic polymer matrix which serve to further enhance antimicrobial resistance. Consequently, novel compounds and innovative methods are urgently required to arrest the proliferation of drug-resistant infections in both nosocomial and community environments. Accordingly, it has been suggested that antimicrobial peptides could be used as novel natural inhibitors that can be used in formulations with synergistically acting antibiotics. Nisin is a member of the lantibiotic family of antimicrobial peptides that exhibit potent antibacterial activity against many Gram-positive bacteria. Recently we have used bioengineering strategies to enhance the activity of nisin against several high profile targets, including multi-drug resistant clinical pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, staphylococci, and streptococci associated with bovine mastitis. We have also identified nisin derivatives with an enhanced ability to impair biofilm formation and to reduce the density of established biofilms of methicillin resistant S. pseudintermedius. The present study was aimed at evaluating the potential of nisin and nisin derivatives to increase the efficacy of conventional antibiotics and to assess the possibility of killing and/or eradicating biofilm-associated cells of a variety of staphylococcal targets. Growth curve-based comparisons established that combinations of derivatives nisin V + penicillin or nisin I4V + chloramphenicol had an enhanced inhibitory effect against S. aureus SA113 and S. pseudintermedius DSM21284, respectively, compared to the equivalent nisin A + antibiotic combinations or when each antimicrobial was administered alone. Furthermore, the metabolic activity of established biofilms treated with nisin

  19. ANTIBIOGRAM OF BACTERIA ISOLATED FROM KUNUN-ZAKI DRINK SOLD IN KEFFI METROPOLIS

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    Makwin Danladi Makut

    2013-01-01

    Full Text Available Kunun-zaki drink is a locally prepared indigenous non-alcoholic beverage that is widely produced and consumed in Nigeria. Standard microbiological methods were employed to isolate bacteria from Kunun-zaki drink sold in Keffi metropolis, Nasarawa State, Nigeria. Samples of Kunun-zaki drink were collected from ten (10 different locations and their bacteriological loads were determined in terms of total bacterial counts using standard methods involving pour plate. The antibiotic resistance pattern of the bacterial isolates against some antibiotics was determined using the Kirby-Bauer disk diffusion method. The bacterial counts of the Kunun-zaki in the ten different locations range from 9.1×108 to 2.6×108 cfu/mL. Four species of bacteria were isolated and identified by standard microbiological methods and these were Escherichia coli, Enterobacter aerogenes, Staphylococcus aureus and Streptococcus spp. The most predominant isolate in terms of occurrence was Escherichia coli (100% followed by Enterobacter aerogenes (70%, Staphylococcus areus (30% and Streptococcus spp (10%. Escherichia coli showed high resistance to Chloramphenicol (75%, followed by Septrin (68.7% and Sparfloxacin (68.7%, while Enterobacter aerogenes, Streptococcus spp and Staphylococcus areus had low rates of resistance to all the antibiotics tested. E. coli had very sensitivity to Pefloxacin (100%, Gentamicin (88%, Amoxicillin (88%, Augmentin (75%, Tarivid (68.7% and Streptomycin (68.7%. Streptococus spp are the most susceptible isolates which had 100% sensitivity to Septrin, Chloramphenicol, Amoxicillin, Gentamicin and Pefloxacin respectively and this was followed by Staphylococcus areus which had 100% sensitivity to Chloramphenicol, Amoxicillin, Augmentin and Tarivid respectively. The antibiotic resistance pattern exhibited by E. coli isolated from the Kunun-zaki sold in Keffi is indicative of possible abuse of the use of antibiotics and this has serious health implications

  20. Selection and characterization of a promoter for expression of single-copy recombinant genes in Gram-positive bacteria

    Directory of Open Access Journals (Sweden)

    Manganelli Riccardo

    2005-01-01

    Full Text Available Abstract Background In the past ten years there has been a growing interest in engineering Gram-positive bacteria for biotechnological applications, including vaccine delivery and production of recombinant proteins. Usually, bacteria are manipulated using plasmid expression vectors. The major limitation of this approach is due to the fact that recombinant plasmids are often lost from the bacterial culture upon removal of antibiotic selection. We have developed a genetic system based on suicide vectors on conjugative transposons allowing stable integration of recombinant DNA into the chromosome of transformable and non-transformable Gram-positive bacteria. Results The aim of this work was to select a strong chromosomal promoter from Streptococcus gordonii to improve this genetic system making it suitable for expression of single-copy recombinant genes. To achieve this task, a promoterless gene encoding a chloramphenicol acetyltransferase (cat, was randomly integrated into the S. gordonii chromosome and transformants were selected for chloramphenicol resistance. Three out of eighteen chloramphenicol resistant transformants selected exhibited 100% stability of the phenotype and only one of them, GP215, carried the cat gene integrated as a single copy. A DNA fragment of 600 base pairs exhibiting promoter activity was isolated from GP215 and sequenced. The 5' end of its corresponding mRNA was determined by primer extention analysis and the putative -10 and a -35 regions were identified. To study the possibility of using this promoter (PP for single copy heterologous gene expression, we created transcriptional fusions of PP with genes encoding surface recombinant proteins in a vector capable of integrating into the conjugative transposon Tn916. Surface recombinant proteins whose expression was controlled by the PP promoter were detected in Tn916-containing strains of S. gordonii and Bacillus subtilis after single copy chromosomal integration of the

  1. ANTIMICROBIAL ACTIVITY OF MICROORGANISMS AND COLLOIDAL SILVER BASED ON COMPLEX MATERIALS

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    Voitenko O. Yu.

    2014-02-01

    Full Text Available The antimicrobial properties of complex materials containing ultradispersed silver particles directly formed in the Candida albіcans, Escherichia сolі, Pseudomonas fluorescens, and Bacillus cereus cell walls were investigated. Complex material based on pseudomonas was more active against gram-positive bacteria, the yeast like fungi based material was mainly active against colibacillus. After a cell-matrix treatment in a hypertonic solution or by acid hydrolysis, the antimicrobial properties of complex materials increased by 20—40%. In a liquid-phase medium, the complex materials with incorporated silver particles in composition with antibiotics strengthened anti-microbial properties of chloramphenicol, tetracycline and amoxiclav antibiotics with respect to E. faecalis, as well as penicillin antibiotics (ceftriaxone, cefotaxime, amoxicillin, amoxiclav against E. coli. The obtained data can serve as a basis for development of the new antibacterial and fungicide cells based materials impregnated with ultradispersed substances.

  2. Contamination of water wells in Khoms city with pathogenic coliform bacteria

    International Nuclear Information System (INIS)

    240 Samples from 60 water wells in and around the area of city of Khoms city (in northwestern Libya) were analyzed over four successive seasons for count of faecal Coliform bacteria, of which antibiotic resistance was later assessed. Standard methods were used for analysis of faecla coliform bacteria. Water wells contained varying levels of faecal coliform bacteria ranging from a Most Probable Number of 0 to 1.8 x 103 cfu/100 ml, with zero isolates at autumn and winter seasons, while wells dug at private farms had the highest percentage of contamination, reaching 56.6% of wells in autumn, and also had the highest number of faecal coliform isolates, 1,8x103 cfu/100 ml, in spring and summer seasons, strains of isolated Escherichia coli were most sensitive to chloramphenicol, and most resistant to tetracycline. (author)

  3. Genetic transformation of marine cyanobacterium Synechococcus sp. CC9311 (Cyanophyceae) by electroporation

    Science.gov (United States)

    Chen, Huaxin; Lin, Hanzhi; Jiang, Peng; Li, Fuchao; Qin, Song

    2013-03-01

    Synechococcus sp. CC9311 is a marine cyanobacterium characterized by type IV chromatic acclimation (CA). A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA. The results show that Synechococcus sp. CC9311 cells were sensitive to four commonly used antibiotics: ampicillin, kanamycin, spectinomycin, and chloramphenicol. An integrative plasmid to disrupt the putative phycoerythrin lyase gene mpeV, using a kanamycin resistance gene as selectable marker, was constructed by recombinant polymerase chain reaction. The plasmid was then transformed into Synechococcus sp. CC9311 via electroporation. High transformation efficiency was achieved at a field strength of 2 kV/cm. DNA analysis showed that mpeV was fully disrupted following challenge of the transformants with a high concentration of kanamycin. In addition, the transformants that displayed poor growth on agar SN medium could be successfully plated on agarose SN medium.

  4. Translocation of integron-associated resistance in a natural system: Acquisition of resistance determinants by Inc P and Inc W Plasmids from Salmonella enterica Typhimurium DT104

    DEFF Research Database (Denmark)

    Sandvang, Dorthe; Diggle, M.; Platt, D.J.

    2002-01-01

    tetracycline). A range of natural plasmids was used as targets for the translocation of resistance. Plasmids that acquired resistance from the DT104 chromosome were segregated by conjugation into Escherichia coli K12. Plasmids R751, R388, and RP4::Tn7 acquired several combinations of resistance determinant......Salmonella enterica Typhimurium DT104, 961368, a veterinary field isolate that encodes a chromosomal cluster of resistance genes as well as two integrons, was used to study the mobility of resistance cassettes (aadA2 and pse-1) and nonintegron-associated resistance determinants (chloramphenicol and...... (including single cassettes) at frequencies comparable with transposition. RP4 and pOG660 did not acquire any determinants from DT104. Phenotypic and PCR-based analysis of all the transconjugants that were translocated-both cassettes and more complex combinations of determinants-was carried out to...

  5. Unusual properties of adenovirus E2E transcription by RNA polymerase III.

    Science.gov (United States)

    Huang, Wenlin; Flint, S J

    2003-04-01

    In adenovirus type 5-infected cells, RNA polymerase III transcription of a gene superimposed on the 5' end of the E2E RNA polymerase II transcription unit produces two small (chase method appear to account for their limited accumulation. The transcription of E2E sequences by RNA polymerase II and III in cells infected by recombinant adenoviruses carrying ectopic E2E-CAT (chloramphenicol transferase) reporter genes with mutations in E2E promoter sequences was also examined. The results of these experiments indicate that recognition of the E2E promoter by the RNA polymerase II transcriptional machinery in infected cells limits transcription by RNA polymerase III, and vice versa. Such transcriptional competition and the properties of E2E RNAs made by RNA polymerase III suggest that the function of this viral RNA polymerase III transcription unit is unusual. PMID:12634361

  6. Typing and Antibiogram of Vibrio cholerae Isolates from a Tertiary Care Hospital in Pune: A 3 Year Study

    Science.gov (United States)

    Palewar, Meghna S; Choure, Archana C; Mudshingkar, Swati; Dohe, Vaishali; Kagal, Anju; Bhardwaj, Renu; Jaiswal, Abhishek; Sarkar, Banwarilal

    2015-01-01

    A retrospective analysis was done over a period of 3 years (January 2010- December 2012) in a tertiary care hospital, Pune, to note the changes in the prevalence and distribution of biotypes, serotypes, antibiotic susceptibility pattern and phage types of Vibrio cholerae isolates from clinical samples so as to be vigilant and curtail major outbreak in future. Vibrio cholerae isolates were obtained from 4.4% of the 1126 fecal specimens processed from cases of acute watery diarrhea. Majority of the isolates were identified as V. cholerae O1 biotype El Tor serotype Ogawa (98%); Phage 27 was the predominant type (77.5%). Majority of the cases were encountered during the months June-August (68%). Antibiogram over a period of 3 years showed that isolates were consistently resistant to Ampicillin (90%) and Furazolidone (88%). Low level of resistance was seen with Norfloxacin (8%), Gentamicin (8%) and Tetracycline (6%). All isolates were susceptible to Chloramphenicol. PMID:25722619

  7. Typing and antibiogram of Vibrio cholerae isolates from a tertiary care hospital in Pune: A 3 year study

    Directory of Open Access Journals (Sweden)

    Meghna S Palewar

    2015-01-01

    Full Text Available A retrospective analysis was done over a period of 3 years (January 2010- December 2012 in a tertiary care hospital, Pune, to note the changes in the prevalence and distribution of biotypes, serotypes, antibiotic susceptibility pattern and phage types of Vibrio cholerae isolates from clinical samples so as to be vigilant and curtail major outbreak in future. Vibrio cholerae isolates were obtained from 4.4% of the 1126 fecal specimens processed from cases of acute watery diarrhea. Majority of the isolates were identified as V. cholerae O1 biotype El Tor serotype Ogawa (98%; Phage 27 was the predominant type (77.5%. Majority of the cases were encountered during the months June-August (68%. Antibiogram over a period of 3 years showed that isolates were consistently resistant to Ampicillin (90% and Furazolidone (88%. Low level of resistance was seen with Norfloxacin (8%, Gentamicin (8% and Tetracycline (6%. All isolates were susceptible to Chloramphenicol.

  8. Urinary tract infection among pregnant women in Al-Mukalla district, Yemen.

    Science.gov (United States)

    Al-Haddad, A M

    2005-05-01

    Urinary tract infection (UTI) is a common problem in pregnant woman. This study examined the frequency of UTI in 137 pregnant women attending Al Mukalla maternity hospital from January to June 2002. Urine samples were examined for UTI microscopically and by culture, and sensitivity tests were done for the organisms isolated using a range of antibiotics. Information on age, trimester, parity and number of pregnancies were also collected for each woman. This study showed that 30% of the women suffered from UTI; Escherichia coli was the most frequently isolated organism (41.5%), and it was highly susceptible to chloramphenicol, ciprofloxacin, ceftizoxime and amikacin. Of the variables examined, 53.7% of the infected women were in the age group 15-24 years, 48.8% were in their 3rd trimester and 75.6% had 1-3 children. PMID:16602474

  9. DNA synthesis in toluene-treated bacteriophage-infected minicells of Bacillus subtilis

    International Nuclear Information System (INIS)

    Bateriophage (phi29, SPP1, or SP01)-infected, toluene-treated minicells of Bacillus subtilis are capable of limited amounts of non-replicative DNA synthesis as measured by incorporation of [3H]dTTP into a trichloroacetic acid-precipitable form. The [3H]dTTP is covalently incorporated into small DNA fragments which result from the degradation of a small percentage of the infecting phage genomes (molecular weights in the range of 2.105). Short exposure of the DNA molecules containing the incorporated [3H]dTMP to Escherichia coli exonuclease III results in over 90% of the [3H]dTMP being converted to a trichloroacetic acid-soluble form. The synthesis is totally dependent on host-cell enzymes and is not inhibited by the addition of chloramphenicol, rifampicin, nalidixic acid and mitomycin C and only slightly (approx. 20%) inhibited by the addition of 6-(p-hydroxyphenylazo)-uracil. (Auth.)

  10. Isolation of Streptococci from Milk Samples of Normal, Acute and Subclinical Mastitis Cows and Determination of Their Antibiotic Susceptibility Patterns

    Directory of Open Access Journals (Sweden)

    Azizollah Ebrahimi

    2008-01-01

    Full Text Available Streptococci are frequently isolated from bovine mastitis in dairy cows with only limited information available on the antimicrobial susceptibility of these organisms. A total of 42 Streptococci isolated from 148 milk samples of normal, sub acute and acute bovine mastitis cases. Overall, 35% of the strains tested were Streptococcus dysgalactiae, Streptococcus agalactiae 26%, Streptococcus uberis 18 and 4% were Enterococcus sp. Differences between the number of isolations in acute and sub acute groups were statistically significant, (p<0.5. The antimicrobial susceptibility for these organisms was determined for the following antimicrobial agents: cephalexine, penicillin, clindamycin, cloxaciline, gentamicin, streptomycin, amoxicillin, tetracycline, kanamycin, oxytetracycline, ampicillin, chloramphenicol and erythromycin. S. agalactiae, S. dysgalactiae, S. uberis and Enterococci demonstrated high level of resistance against streptomycin, penicillin and cloxaciline. Low level of sensitivity to other tested antimicrobials was demonstrated.

  11. Research on Application of Electrochemical Immune Sensors in Food Safety Detection

    Directory of Open Access Journals (Sweden)

    Lichao Zhang

    2015-08-01

    Full Text Available Currently, research on toxic and hazardous substance in food immunological detection methods focused on conventional enzyme-linked immunosorbent assay, especially relatively few studies Array Detection of toxic foods for electrochemical immunoassay method of harmful substances. The work to build a variety of stable performance, high selectivity and sensitivity of electrochemical immunosensor and applied to the detection of Sudan, clenbuterol and chloramphenicol and other foods toxic and hazardous materials. And for the sample of the large number of food safety testing, testing and testing required to have many kinds of characteristics such as age, photo-electrochemical immune sensor array was prepared and applied to veterinary drug residues in food in a fast, high-throughput analysis.

  12. Susceptibilidad in vitro de Arcobacter butzleri a seis drogas antimicrobianas In vitro susceptibility of Arcobacter butzleri to six antimicrobial drugs

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    L. Otth

    2004-12-01

    Full Text Available Se determinaron los patrones de susceptibilidad de 50 cepas de A. butzleri mediante el método del E-test. Ninguna cepa fue resistente a gentamicina y tetraciclina, pero, hubo cepas resistentes a eritromicina (2% y ciprofloxacina (2%. Además, el 90 y el 98% de las cepas fueron resistentes a ampicilina y cloramfenicol respectivamente. Solamente dos de las 45 cepas ampicilina-resistentes fueron productoras de ß-lactamasa. Palabras clave: Arcobacter butzleri, susceptibilidad antimicrobiana, bacterias emergentes, E-test, ß-lactamasaThe susceptibility patterns of 50 A. butzleri strains to six antimicrobial agents were determined using the E-test method. No strain was found to be resistant to gentamicin and tetracycline, but two different strains (2% were resistant to erythromycin and ciprofloxacin. Ninety and 98% of the strains were resistant to ampicillin and chloramphenicol, respectively. Only two of the 45 ampicillin resistant strains were able to produce ß-lactamase.

  13. National surveillance of Salmonella enterica in food-producing animals in Japan

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    Kijima Mayumi

    2009-08-01

    Full Text Available Abstract A total of 518 fecal samples collected from 183 apparently healthy cattle, 180 pigs and 155 broilers throughout Japan in 1999 were examined to determine the prevalence and antimicrobial susceptibility of Salmonella. The isolation rates were 36.1% in broilers, 2.8% in pigs and 0.5% in cattle. S. enterica Infantis was the most frequent isolate, found in 22.6% of broiler fecal samples. Higher resistance rates were observed against oxytetracycline (82.0%, dihydrostreptomycin (77.9%, kanamycin (41.0% and trimethoprim (35.2%. Resistance rates to ampicillin, ceftiofur, bicozamycin, chloramphenicol and nalidixic acid were S. enterica Senftenberg was found in the isolates obtained from one broiler fecal sample. This is the first report of cephalosporin-resistant Salmonella directly isolated from food animal in Japan.

  14. Prevalence and antibiotic susceptibility of Bacteroides fragilis group isolated from stool samples in North Lebanon

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    Mariam Yehya

    2013-09-01

    Full Text Available Fifty one strains of the Bacteroides fragilis group were isolated from 45 fecal samples. Classical phenotypic identification showed that 16 isolates were B. thetaiotaomicron, 12 B. uniformis, 9 B. eggerthii,7 B. vulgatus,3 B. caccae,2 Parabacteroides distasonis with 1 identified B. ovatus and 1 B. fragilis. The 51 strains were tested for susceptibility against 16 antimicrobial agents and the MICs for metronidazole were determined. The tests showed that imipenem, meropenem and chloram-phenicol were the most effective antibiotics (98%, 98% and 92.16% of susceptibility, respectively followed by ticarcillin/clavulanic acid, piperacillin/tazobactam, rifampin (88.24% susceptibility, moxifloxacin 86.27% and tigecycline 84.31%. Ofloxacin and cefotaxime were the least effective antibiotics with 27.45% and 0% of activity respectively. Only six of the 51 isolated strains were resistant to metronidazole with MICs = 64 mg/L (1 strain and > 256 mg/L (5 strains.

  15. ISOLATION IPG3-1 AND IPG3-3, ENDOPHYTIC FUNGI FROM DELIMA (PUNICA GRANATUM LINN. TWIGS AND IN VITRO ASSESSMENT OF THEIR ANTI MICROBIAL ACTIVITY

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    Shirly Kumala

    2013-06-01

    Full Text Available IPG3-1,2,3,4,5 were endophytic fungi isolated from Delima twigs via direct seed inoculation on Potato Dextrose Agar (PDA. Macroscopic identification of the isolates showed clearly that IPG3-3 and 4 have radial wrinkles in the centre with black spots while IPG3-5 has flower shape in the middle. The microscopic observation on the other hand, showed that IPG3-1 and 3 has branched septate while IPG3-4 has unbranched septate. Furthermore, IPG3-2 and 5 were branched but septateless. Overall, these endophytes showed no spore formation. Secondary metabolites of IPG3-1 and IPG3-3 endophytic fungi isolates demonstrated stronger inhibition zone percentage against Candida albicans and than towards Staphylococcus aureus and Escherichia coli when campare to their respectively positive control amphotericin B and Chloramphenicol.

  16. Targeting of gene expression to skeletal and cardiac muscle of trangenic animals.

    Science.gov (United States)

    Sands, A T; DeMayo, F; Lei, X; Schwartz, R J

    1991-01-01

    The tissue restricted and developmental potentiation of transcription by chicken alpha-skeletal actin promoter regions fused to the reporter gene chloramphenicol acetyl transferase (CAT) were characterized in transgenic mice. Six of eight expressing transgenic mouse lines containing the chicken alpha-skeletal actin promoter fused to CAT resulted in preferential transgene transcription in skeletal muscle tissue, similar to the endogenous mouse alpha-skeletal actin gene. Two of the eight lines departed from the preferred pattern of skeletal muscle expression with primary expression of the transgene in the heart, a tissue containing primarily cardiac actin isoforms. Developmentally, a transition from embryonic heart to fetal and neonatal skeletal muscle expression was produced by the transgene promoter, a pattern of regulation similar to that of the endogenous alpha-skeletal actin gene. Instances of departure of transgene expression from the endogenous gene implied the existance of higher order muscle gene regulatory mechanisms. PMID:1367249

  17. Inhibition of mammalian mitochondrial protein synthesis by oxazolidinones.

    Science.gov (United States)

    McKee, E E; Ferguson, M; Bentley, A T; Marks, T A

    2006-06-01

    The effects of a variety of oxazolidinones, with different antibacterial potencies, including linezolid, on mitochondrial protein synthesis were determined in intact mitochondria isolated from rat heart and liver and rabbit heart and bone marrow. The results demonstrate that a general feature of the oxazolidinone class of antibiotics is the inhibition of mammalian mitochondrial protein synthesis. Inhibition was similar in mitochondria from all tissues studied. Further, oxazolidinones that were very potent as antibiotics were uniformly potent in inhibiting mitochondrial protein synthesis. These results were compared to the inhibitory profiles of other antibiotics that function by inhibiting bacterial protein synthesis. Of these, chloramphenicol and tetracycline were significant inhibitors of mammalian mitochondrial protein synthesis while the macrolides, lincosamides, and aminoglycosides were not. Development of future antibiotics from the oxazolidinone class will have to evaluate potential mitochondrial toxicity. PMID:16723564

  18. Antimicrobial Activity and Antibiotic Sensitivity of Three Isolates of Lactic Acid Bacteria From Fermented Fish Product, Budu

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    Liasi, S. A.

    2009-01-01

    Full Text Available Three isolates of lactic acid bacteria (LAB from the fermented food product, Budu, were identified as genus lactobacillus (Lactobacillus casei LA17, Lactobacillus plantarum LA22 and L. paracasei LA02, and the highest population was Lb. paracasei LA02. The antibacterial agent produced by the isolates inhibited the growth of a range of gram-positive and gram-negative microorganisms. Antimicrobial sensitivity test to 18 different types of antibiotic were evaluated using the disc diffusion method. Inhibition zone diameter was measured and calculated from the means of five determinations and expressed in terms of resistance or susceptibility. All the LAB isolates were resistant to colestin sulphate, streptomycin, amikacin, norfloxacin, nalidixic acid, mecillinam, sulphanethoxazole/ trimethoprim, kanamycin, neomycin, bacitracin and gentamycin but susceptible to erythromycin, penicillin G, chloramphenicol, tetracycline, ampicillin and nitrofurantion.

  19. Studies on the pathogenic bacterium of ulcer disease in Epinephelus awoara

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Studies were conducted to determine the cause of the acute mortality of cage-cultured Epinephelus awoara in the Tong'an Bay of Xiamen, China during the summer of 2002. Predominant bacteria strain TS-628 was isolated from the diseased grouper. The virulence test confirmed that TS-628 was the pathogenic bacterium. Biochemical characteristics of the isolates were determined using the automatic bacterial identification system and standard tube tests. To further confirm the identification, a 1 121 bp 16S rRNA gene sequence of the isolate was amplified by PCR, which had been deposited into Genbank (accession number: AY747308). According to the biochemical characteristics and by comparing the 16S rRNA gene homology of the isolate, the pathogenic bacterium was identified as Vibrio harveyi. Drug sensitivity tests showed that this pathogenic bacterium was sensitive to 16 antibacterials, especially to chloramphenicol and actinospectacin, but completely resistant to antibacterials likes vancomycin, penicillin, lincomycin, and so on.

  20. Chlorine and antibiotic-resistant bacilli isolated from an effluent treatment plant - doi: 10.4025/actascitechnol.v35i1.12951

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    Suzana Cláudia Silveira Martins

    2013-01-01

    Full Text Available Resistance to different concentrations of chlorine and the susceptibility to antibiotics by bacteria isolated from the final effluent of the Pici Campus wastewater treatment plant of the Federal University of Ceará (UFC is evaluated. Twelve strains, morphologically and biochemically identified as belonging to the genus Bacillus, were selected. The strains were submitted to sodium hypochlorite at different contact times and tested against the antibiotics amoxicillin, erythromycin, chloramphenicol, tetracycline, and vancomycin. All strains were resistant to concentration 0.1 ppm chlorine up to 30 minutes, but bacteria resistant to concentrations up to 5,000 ppm for 10 minutes were detected. Bacterial growth was impaired in 10,000 ppm concentration. The strains presented three antibiotic resistance profiles, 50% were sensitive to all antibiotics, 25% were resistant to one antibiotic and 25% were resistant to two antibiotics.  

  1. Chlorophyll biosynthesis and assembly into chlorophyll-protein complexes in isolated developing chloroplasts

    International Nuclear Information System (INIS)

    Isolated developing plastids from greening cucumber cotyledons or from photoperiodically grown pea seedlings incorporated 14C-labeled 5-aminolevulinic acid (ALA) into chlorophyll (Chl). Incorporation was light dependent, enhanced by S-adenosylmethionine, and linear for 1 hr. The in vitro rate of Chl synthesis from ALA was comparable to the in vivo rate of Chl accumulation. Levulinic acid and dioxoheptanoic acid strongly inhibited Chl synthesis but not plastid protein synthesis. Neither chloramphenicol nor spectinomycin affected Chl synthesis, although protein synthesis was strongly inhibited. Components of thylakoid membranes from plastids incubated with [14C]ALA were resolved by electrophoresis and then subjected to autoradiography. This work showed that (i) newly synthesized Chl was assembled into Chl-protein complexes and (ii) the inhibition of protein synthesis during the incubation did not alter the labeling pattern. Thus, there was no observable short-term coregulation between Chl synthesis (from ALA) and the synthesis of membrane proteins in isolated plastids

  2. Solid phase extraction of penicillins from milk by using sacrificial silica beads as a support for a molecular imprint

    International Nuclear Information System (INIS)

    We have prepared molecularly imprinted beads with molecular recognition capability for target molecules containing the penicillanic acid substructure. They were prepared by (a) grafting mesoporous silica beads with 6-aminopenicillanic acid as the mimic template, (b) filling the pores with a polymerized mixture of methacrylic acid and trimethylolpropane trimethacrylate, and (c) removing the silica support with ammonium fluoride. The resulting imprinted beads showed good molecular recognition capability for various penicillanic species, while antibiotics such as cephalosporins or chloramphenicol were poorly recognized. The imprinted beads were used to extract penicillin V, nafcillin, oxacillin, cloxacillin and dicloxacillin from skimmed and deproteinized milk in the concentration range of 5–100 μg·L−1. The extracts were then analyzed by micellar electrokinetic chromatography by applying reverse polarity staking as an in-capillary preconcentration step, and this resulted in a fast and affordable method within the MRL levels, characterized by minimal pretreatment steps and recoveries of 64–90 %. (author)

  3. Non-specific seminal tract infection and male infertility : a bacteriological study.

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    Mogra N

    1981-04-01

    Full Text Available 70 infertile males with epididymal tenderness, pus cells in the semen, and/or history of urinary tract infection were studied by semen culture examination. Significant growth of Streptococcus fecalis, Escherichia coli, coagulase positive Staphylococci, Proteus valgaris, Pseudomonas pyocyanea, and beta hemolytic Strepticocci was found in 42.9% of the cases. Most of the tested strains were sensitive to ampicillin, cotrimoxazole, nitrofurantoin, erythromycin, and chloramphenicol. In a control group of 20 healthy fertile males, only an insignificnat growth of Staphylococcus albus and Streptococcus facalis was found in 65% of the samples. Nonspecific seminal tract infection can be an important cause of male infertility. These infections may affect fertility in several ways: by damaging sperm, hampering their motility, altering the chemical composition of the seminal fluid, or by producing an inflammatory structure in the tract. Seminal infection could also be the cause of the chronicity of urinary tract infection by acting as the reservoir of infection.

  4. Cytoplasmic sequences of the growth hormone receptor necessary for signal transduction

    DEFF Research Database (Denmark)

    Goujon, L; Allevato, G; Simonin, G;

    1994-01-01

    -dependent genes encoding ovine beta-lactoglobulin or serine protease inhibitor 2.1 (Spi 2.1, formerly Spi.1; the corresponding rat gene has recently been redesignated Spin2a) coupled to the bacterial reporter gene encoding chloramphenicol acetyltransferase (CAT). Transfected cells were grown in the absence and...... presence of human GH and dexamethasone for the Spi 2.1 gene construct. GH was able to activate each promoter (with approximately 4-fold induction of CAT activity) in a dose-dependent manner. For both tests, the maximal effect was observed at 20 nM human GH. These tests have been used to identify functional...... domains of the GHR. Two truncated (T) GHRs, lacking most or part of the cytoplasmic domain [called T276 (ending at residue 276) and T436 (ending at residue 436)], were unable to stimulate CAT activity. The GHR contains a proline-rich region, called "Box I," conserved in the cytokine/GH/prolactin receptor...

  5. COMPARATIVE ASSESSMENT OF MILK BORNE PATHOGENS AND THEIR ANTIBACTERIAL SENSITIVITY

    Directory of Open Access Journals (Sweden)

    Priyanka Chaudhary et al

    2012-10-01

    Full Text Available Milk is considered as a highly nutritious and valuable human food, consumed by the people in a variety of different products. The present work is an effort to have a survey of number of bacteria present in different milk samples viz., Raw, Boiled, Pasteurized and Skimmed milk collected from local market of Haridwar and its adjoining areas by serial dilution method and the quality of milk assessed by MBRT. The highest mean count was detected in raw milk having 211±0.8 cfu/ml. Among the four types, boiled milk appeared as of best quality. The major microbial contaminants were found to be Bacillus sp, Staphylococcus sp, Streptococcus sp, E. coli and Micrococcus sp. During the present investigation the antibiotic sensitivity test was also performed against all the five genera isolated. It was found that inhibition zone of Chloramphenicol and Ofloxacin was maximum against Streptococcus sp. (24 mm and Staphylococcus sp. (30mm.

  6. Susceptibility of bifidobacteria of animal origin to selected antimicrobial agents.

    Science.gov (United States)

    Mayrhofer, Sigrid; Mair, Christiane; Kneifel, Wolfgang; Domig, Konrad J

    2011-01-01

    Strains of the genus Bifidobacterium are frequently used as probiotics, for which the absence of acquired antimicrobial resistance has become an important safety criterion. This clarifies the need for antibiotic susceptibility data for bifidobacteria. Based on a recently published standard for antimicrobial susceptibility testing of bifidobacteria with broth microdilution method, the range of susceptibility to selected antibiotics in 117 animal bifidobacterial strains was examined. Narrow unimodal MIC distributions either situated at the low-end (chloramphenicol, linezolid, and quinupristin/dalfopristin) or high-end (kanamycin, neomycin) concentration range could be detected. In contrast, the MIC distribution of trimethoprim was multimodal. Data derived from this study can be used as a basis for reviewing or verifying present microbiological breakpoints suggested by regulatory agencies to assess the safety of these micro-organisms intended for the use in probiotics. PMID:22312561

  7. Antimicrobial activity of tigecycline against community-acquired methicillin-resistant Staphylococcus aureus isolates recovered from North American medical centers.

    Science.gov (United States)

    Mendes, Rodrigo E; Sader, Helio S; Deshpande, Lalitagauri; Jones, Ronald N

    2008-04-01

    A total of 1989 community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) were susceptibility tested by broth microdilution. Pulsed-field gel electrophoresis, SCCmec type, and polymerase chain reaction for Panton-Valentine leukocidin (PVL) genes were also performed. The overall tigecycline susceptibility rate was 98.2%. Glycopeptides, quinupristin/dalfopristin, linezolid, and chloramphenicol were also active against this collection (< or =0.7% resistant). The vast majority (70.8%) of the CA-MRSA was SCCmec type IV, from which 88.4% belonged to the USA300-0114 clone and 94.7% were PVL positive. Tigecycline showed in vitro activity comparable with other highly active parenteral agents and represents an option for treating complicated infections caused by CA-MRSA. PMID:18068326

  8. Synthesis and Biological Evaluation of Some Novel Dithiocarbamate Derivatives

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    Begüm Nurpelin Sağlık

    2014-01-01

    Full Text Available 18 novel dithiocarbamate derivatives were synthesized in order to investigate their inhibitory potency on acetylcholinesterase enzyme and antimicrobial activity. Structures of the synthesized compounds were elucidated by spectral data and elemental analyses. The synthesized compounds showed low enzyme inhibitory activity. However, they displayed good antimicrobial activity profile. Antibacterial activity of compounds 4a, 4e, and 4p (MIC = 25 μg/mL was equal to that of chloramphenicol against Klebsiella pneumoniae (ATCC 700603 and Escherichia coli (ATCC 35218. Most of the compounds exhibited notable antifungal activity against Candida albicans (ATCC 10231, Candida glabrata (ATCC 90030, Candida krusei (ATCC 6258, and Candida parapsilosis (ATCC 7330. Moreover, compound 4a, which carries piperidin-1-yl substituent and dimethylthiocarbamoyl side chain as variable group, showed twofold better anticandidal effect against all Candida species than reference drug ketoconazole.

  9. Expression of a human placental alkaline phosphatase gene in transfected cells: Use as a reporter for studies of gene expression

    International Nuclear Information System (INIS)

    The human placental alkaline phosphatase gene has been cloned and reintroduced into mammalian cells. When a plasmid carrying the gene under control of the simian virus 40 early promoter (pSV2Apap) is transfected into a variety of different cell types, placental alkaline phosphatase activity can readily be detected by using whole cell suspensions or cell lysates. Alkaline phosphatase activity can also be visualized directly in individual transfected cells by histochemical staining. The gene is appropriate for use as a reporter in studies of gene regulation since its expression is dependent on the presence of exogenous transcription control elements. The overall assay to detect the expression of the gene is quantitative, very rapid, and inexpensive. Cotransfections of cells with pSV2Apap and a related plasmid carrying the bacterial chloramphenicol acetyltransferase gene (pSV2Acat) indicate that transcription of these two genes is detected with roughly the same sensitivity

  10. Antimicrobial susceptibility of clinical isolates of Haemophilus influenzae to ampicillin-sulbactam.

    Science.gov (United States)

    Mortensen, J E; LaRocco, M; Himes, S L; Inderlied, C; Daly, J A; Campos, J M; Mendelman, P M

    1990-01-01

    A total of 1092 clinical isolates of Haemophilus influenzae (306 type b; 786 non-type-b), from five medical centers were obtained during 1987 and 1988. Disk diffusion antimicrobial susceptibilities were obtained for all isolates, and broth microdilution susceptibilities were obtained for 502 isolates. Beta-lactamase was produced by 34.3% of type-b and 22.1% of non-type-b isolates, with some geographic variations. Using disk diffusion antimicrobial susceptibility testing, all isolates were susceptible to ampicillin-sulbactam, ceftriaxone, cefuroxime, and rifampin; two isolates were resistant to chloramphenicol. Whether tested using a fixed ratio of ampicillin to sulbactam of 2:1 or a fixed concentration of sulbactam, the ampicillin-sulbactam combination demonstrated good activity against clinical isolates of H. influenzae. Only 8 of the 1092 isolates did not produce beta-lactamase but demonstrated MICs of greater than or equal to 2 micrograms/ml for ampicillin. PMID:2076596

  11. A New Biocontrol Fungus Trichoderma Kongii in the Kingdom of Saudi Arabia Isolation and Identification

    International Nuclear Information System (INIS)

    A total of 164 soil and root samples of different plant groups were collected from Abu-Arish governorate , Jazan province South West Saudi Arabia during the period of 2004-2005. Each sample contained feeder roots and approximately 250 g soil, taken from a depth of 20 cm of the soil surface. Samples were analyzed by two different media. Culture fungi on Malt Extract Agar identified by Biolog Systems and culture fungi on Potato Dextrose Agar medium containing chloramphenicol were identified by microscopic characterization. Results showed that, 11 different types of fungi isolated from tested samples, Fusarium spp (40%), Rhizoctonia solani,(12%) Trichoderma spp (12%), Macrophomina phaseoina. (7 %), Aspergillus spp (18 %) were the predominant fungal species. Helminthosporium spp (3%), Alternaria alternate (2%), Pythium spp (2%), Curviularia spp (2%), Cladsporium spp. (1%) and Mucor spp. (1%) were less frequent. (author)

  12. An Outbreak of Bartonella bacilliformis in an Endemic Andean Community

    Science.gov (United States)

    Sanchez Clemente, Nuria; Ugarte-Gil, Cesar; Solorzano, Nelson; Maguiña, Ciro; Moore, David

    2016-01-01

    Background Bartonellosis affects small Andean communities in Peru, Colombia and Ecuador. Research in this area has been limited. Methods Retrospective review of 191 cases of bartonellosis managed in Caraz District Hospital, Peru, during the last outbreak (2003). Results The majority of cases (65%) were 14 years old and younger. There was a peak in acute cases after the rainy season; chronic cases presented more constantly throughout the year. The sensitivity of blood smear against blood culture in acute disease was 25%. The most commonly used treatment for chronic disease was rifampicin; chloramphenicol was used to treat most acute cases. Complications arose in 6.8% and there were no deaths. Conclusions Diagnostic and treatment algorithms for acute and chronic bartonellosis have been developed without a strong evidence base. Preparation of ready-to-go operational research protocols for future outbreaks would strengthen the evidence base for diagnostic and treatment strategies and enhance opportunities for control. PMID:26991495

  13. Antimicrobial resistance among Pseudomonas spp. and the Bacillus cereus group isolated from Danish agricultural soil

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Baloda, S.; Boye, Mette;

    2001-01-01

    , when possible, were collected. Soil from a well-characterized Danish farm soil (Hojbakkegaard) was collected for comparison. The Psudomonas spp. and B. cereus were chosen as representative for Gram-negative and Gram-positive indigenous soil bacteria to test the effect of spread of animal waste on...... selection of resistance among soil bacteria. No variations in resistance levels were observed between farms; but when the four differently treated soils were compared, resistance was seen for carbadox, chloramphenicol, nalidixan (nalidixic acid), nitrofurantoin, streptomycin and tetracycline for Pseudomonas...... spp., and for bacitracin, erythromycin, penicillin and streptomycin for the B. cereus group. Variations in resistance levels were observed when soil before and after spread of animal waste was compared, indicating an effect from spread of animal waste....

  14. Identification and antimicrobial susceptibility patterns of Staphylococcus spp. isolated from canine chronic otitis externa

    Directory of Open Access Journals (Sweden)

    Silva N.

    2001-01-01

    Full Text Available Swab samples obtained from 96 dogs with chronic otitis externa were cultured for the isolation of Staphylococcus species. Of 57 staphylococcal strains, 41 (72% were coagulase-negative (CNS. The identification of staphylococci strains was made by standard procedures for the routine identification of staphylococci in clinical practice. S. sciuri was the most frequent species isolated (22.8% from chronic otitis externa in dogs followed by S. intermedius (12.3%, S. auricularis (10.5% and S. aureus (8.8%. Three (5.2% CNS strains could not be identified. Bacterial isolates were susceptible to enrofloxacin, gentamicin, cephalothin, chloramphenicol and neomycin. Resistance was most common to penicillin G, oxacillin and ampicillin.

  15. Poly(ADP-ribose) polymerase inhibitors suppress UV-induced human immunodeficiency virus type 1 gene expression at the posttranscriptional level

    International Nuclear Information System (INIS)

    Gene expression of human immunodeficiency virus type 1 (HIV-1) is induced not only by trans activation mediated through a gene product (tat) encoded by the virus but also by treatment of virus-carrying cells with DNA-damaging agents such as UV light. Employing an artificially constructed DNA in which the chloramphenicol acetyltransferase gene was placed under the control of the HIV-1 long terminal repeat, we analyzed the induction process in HeLa cells and found that inhibitors of poly(ADP-ribose) polymerase suppressed UV-induced HIV-1 gene expression but not tat-mediated expression. We also found that suppression occurs at the posttranscriptional level. These results indicate that HIV-1 gene expression is activated by at least two different mechanisms, one of which involves poly-ADP ribosylation. A possible new role of poly-ADP ribosylation in the regulation of specific gene expression is also discussed

  16. Reassessment of the differential effects of ultraviolet and ionizing radiation on HIV promoter: the use of cell survival as the basis for comparisons

    International Nuclear Information System (INIS)

    Effects of different radiation treatments on the human immunodeficiency virus-1 (HIV) promoter were reassessed for exposures comparable to those encountered in clinical or cosmetic practice, using survival of the host cell as a basis for comparisons. The exposures were performed with two ultraviolet radiation sources commonly used as medical or cosmetic devices (UVASUN 2000 and FS20 lamps), a germicidal (G15T8) lamp and an X-ray machine. The UVC component of the FS20 lamp was filtered out. The emission spectra of the lamps were determined. The characteristics of these sources allowed us to discriminate among effects of UVA1 (340-400 nm), UVB + UVA2 (280-340 nm) and UVC (254 nm) radiations. Effects of irradiation were ascertained using cultures of HeLa cells stably transfected with the HIV promoter linked to a reporter-chloramphenicol acetyl transferase-gene. (Author)

  17. Tween 80 effect on glucosyltransferase synthesis by Streptococcus salivarius.

    Science.gov (United States)

    Wittenberger, C L; Beaman, A J; Lee, L N

    1978-01-01

    Streptococcus salivarius (ATCC 25975) produced very low or nondetectable amounts of the extracellular enzyme glucosyltransferase (GTase) when grown in a chemically defined medium. The addition of Tween 80 to this medium resulted in the production of markedly enhanced levels of the enzyme. Oleic acid, the methyl ester of oleic acid, and sucrose each could not substitute for Tween 80 in this regard. The surfactant had no direct activating effect on performed enzyme activity. Tween 80 also stimulated the production of GTase by concentrated cells suspended in defined medium during a time when no measurable growth occurred. Under these conditions, the stimulatory effect of Tween 80 was blocked by chloramphenicol. It was further found that the surfactant dramatically stimulated the differential rate of GTase synthesis. These and other data strongly suggest that Tween 80 stimulates the production of extracellular GTase by acting either directly or indirectly at the level of enzyme synthesis. PMID:618839

  18. The effects of 5-fluorouracil and doxorubicin on expression of human immunodeficiency virus type 1 long terminal repeat

    Energy Technology Data Exchange (ETDEWEB)

    Panozzo, J.; Akan, E. [Argonne National Lab., IL (United States); Griffiths, T.D. [Northern Illinois Univ., De Kalb, IL (United States). Dept. of Biological Sciences; Woloschak, G.E. [Argonne National Lab., IL (United States)

    1996-03-01

    Previous work by many groups has documented induction of the HIV-LTR following exposure of cells to ultraviolet light and other DNA damaging agents. Our experiments set out to determine the relative activation or repression of the HIV-LTR in response to two classes of chemotherapeutic agents: Doxorubicin is a DNA-damage inducing agent, and 5-fluorouracil has an antimetabolic mode of action. Using HeLa cells stably transfected with a construct in which HIV-LTR drives expression of the chloramphenicol acetyl transferase reporter gene, we demonstrated an up to 10-fold induction following doxorubicin treatment in 24 h post-treatment. This induction was repressed by treatment with salicylic acid, suggesting a role for prostaglandin/cyclo-oxygenase pathways and/or NFKB in the inductive response. Induction by 5-fluorouracil, in contrast, was more modest (two-fold at most) though it was consistently elevated over controls.

  19. Prevalence, antimicrobial resistance and risk factors for thermophilic Campylobacter infections in symptomatic and asymptomatic humans in Tanzania

    DEFF Research Database (Denmark)

    Komba, E. V. G.; Mdegela, R. H.; Msoffe, P. L. M.;

    2015-01-01

    testing employed the disc diffusion method. A small proportion of the test isolates was also subjected to agar dilution method. Risk factors for human illness were determined in an unmatched case-control study. Thermophilic Campylobacter were isolated from 11.4% of the screened individuals (n = 1195). The...... sulphate and lowest for ciprofloxacin (22.1%). The rates of resistance for other antibiotics (azithromycin, erythromycin, tetracycline, cephalothin, gentamycin, nalidixic acid, ampicillin, amoxycillin, norfloxacin, chloramphenicol) ranged from 44.1% to 89%. Comparison between disc diffusion and agar...... dilution methods indicated a good correlation, and the tests were in agreement to each other (κ ≥ 0.75). Human illness was found to be associated with young age and consumption of chicken meat and pre-prepared salad. Our data indicate the presence of antibiotic-resistant thermophilic Campylobacter in...

  20. Isolation and Identification of Vancomycin Resistant Staphylococcus aureus from Post Operative Pus Sample

    Directory of Open Access Journals (Sweden)

    Subhankari Prasad Chakraborty1, Santanu KarMahapatra1, Manjusri Bal2 and Somenath Roy1*

    2011-04-01

    Full Text Available Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Recently, S. aureus have evolved resistance to both synthetic and traditional antibiotics. This study was carried out to isolate pathogenic S. aureus from post-operative pus sample, and VRSA was identified by evaluation of resistance patterns using conventional antibiotics. Thirty post operative pus samples were collected from nearby Hospital and species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. Antibiotic susceptibility tests were carried out by MIC, MBC, DAD test and BHI vancomycin screening agar. VRSA were confirmed by PCR amplification of the vanA and vanB genes. From this study, it was observed that isolated S. aureus strains are pathogenic; 30% of strains were resistant to penicillin G, ampicillin and erythromycin; 26.67% strains were resistant to cephotaxime, gentamycin, streptomycin, tetracycline, chloramphenicol, norfloxacin, methicillin and vancomycin.

  1. Anti-enrofloxacin Antibody Production by Using Enrofloxacin-screened HSA as an Immunogen

    Institute of Scientific and Technical Information of China (English)

    LIU Chune; LIN Hong; CAO Limin; JIANG Jie

    2005-01-01

    A two-step zero-length cross-linking procedure using active esters was successfully adopted for conjugating enrofloxacin (EF) to human serum albumin (HSA). The derived conjugate was characterized by UV spectrum and then used for immunization of BALB/C mice. In enzyme-linked immunosorbent assay (ELISA) and competitive inhibition ELISA experiments, the derived antiserum exhibited high antibody titer (greater than 1: 250 000) as well as varied cross-reactivity (from 97.8% to 161.7%) to three analogs of EF belonging to fluoroquinolones family. But over the concentration range studied, no significant cross-reactivity was observed to other group of antibiotics (chloramphenicol, oxytetracycline, sulphamethoxazole and nysfungin). It was confirmed that the synthesized immunogen was highly antigenic and elicited specific antibody responses in BALB/C mice against EF.

  2. Antimicrobial resistance of Enterococcus spp. isolates from raw beef and meat products.

    Science.gov (United States)

    Sustacková, A; Nápravníková, E; Schlegelová, J

    2004-01-01

    E. faecalis (67%) and E. faecium (13.7%) were most frequently isolated among enterococci that contaminate cooled and frozen processed meat, follow-up heat-treated meat products and unheated fermented dry salami. Most isolates of both species were resistant to cephalothin (95 and 83 %) and clindamycin (77 and 67%, respectively). Furthermore, E. faecalis and E. faecium isolates were resistant to erythromycin (44 and 72%), tetracycline (34.5 and 17.4%), and streptomycin (13.3 and 4.3%, respectively). Only a few of the isolates were resistant to ampicillin, ampicillin-sulbactam, chloramphenicol, and vancomycin while all isolates were susceptible to gentamicin, penicillin, and teicoplanin. During the production of heat-treated meat products, numbers of resistant isolates increased in spite of the decreasing enterococcal contamination of the samples. An opposite situation was found in the production of fermented dry salami. PMID:15530006

  3. Induction of mutations and repair in bacteriophages after photosensitizing action of 8-methoxypsoralen

    International Nuclear Information System (INIS)

    The excision of the 8-methoxypsoralen monoadducts (MA) from temperature lambda and dependent virulent T7 phage DNA by the host cell takes place in non-nutrient medium. The autonomously virulent T4 phage repair kinetics is biphasic. Some MA are repaired in buffer or in nutrient medium containing chloramphenicol (CA). The 2nd repair phase depends on DNA synthesis and phage protein synthesis. Virulent ssub(d) phages can repair MA, unless blocked with CA, only in a nutrient medium. De novo synthesized phage proteins seem to participate in repair of phage ssub(d). ssub(d) phages were used to study the mutagenic effect of MA and diadducts (cross-links) of 8-methoxypsoralen. Mutations were induced by MA mainly, while the lethal effect was due to diadducts. (author)

  4. One-Pot Green Synthesis and Bioapplication of l-Arginine-Capped Superparamagnetic Fe3O4 Nanoparticles

    Science.gov (United States)

    Lai, Yongchao; Yin, Weiwei; Liu, Jinting; Xi, Rimo; Zhan, Jinhua

    2010-02-01

    Water-soluble l-arginine-capped Fe3O4 nanoparticles were synthesized using a one-pot and green method. Nontoxic, renewable and inexpensive reagents including FeCl3, l-arginine, glycerol and water were chosen as raw materials. Fe3O4 nanoparticles show different dispersive states in acidic and alkaline solutions for the two distinct forms of surface binding l-arginine. Powder X-ray diffraction and X-ray photoelectron spectroscopy were used to identify the structure of Fe3O4 nanocrystals. The products behave like superparamagnetism at room temperature with saturation magnetization of 49.9 emu g-1 and negligible remanence or coercivity. In the presence of 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride, the anti-chloramphenicol monoclonal antibodies were connected to the l-arginine-capped magnetite nanoparticles. The as-prepared conjugates could be used in immunomagnetic assay.

  5. Salicylic acid inhibits UV- and Cis-Pt-induced human immunodeficiency virus expression

    International Nuclear Information System (INIS)

    Previous studies have shown that exposure of HeLa cells stably transfected with a human immunodeficiency virus-long terminal repeat-chloramphenicol acetyl transferase (HIV-LTR-CAT) construct to UV light-induced expression from the HIV LTR. By culturing the cells with salicylic acid we demonstrated dose-dependent repression of this induced HIV expression. Repression was evident if salicylic acid was administered 2 h before, at the same time as, or up to 6 h after exposure to the DNA-damaging agent. The kinetics were similar for UV- and for cis-Pt-induced HIV expression, and induction was dependent on the UV dose or cis-Pt concentration added to the culture. These results suggest a role for the prostaglandins or the cyclooxygenase pathway or both in HIV induction mediated by DNA-damaging agents

  6. Salmonella Enteritidis infection in young broiler chickens from breeding farm: A case report

    Directory of Open Access Journals (Sweden)

    Sri Poernomo

    1997-10-01

    Full Text Available old from a breeding farm not far from Bogor. Samples were examined pathologic anatomically (PA and bacteriologically to isolate the causative agents . The sensitivity of the main causative agents isolated from the samples was tested with some drugs, while its pathogenicity was tested in 3 days old chickens intramuscularly, subcutaneously, intraperitoneally and orally, three chickens per inoculations . Exudative and caseous omphalitis, pericarditis, hepatitis, sirsacculitis, and coxofemoral and knee joints were observed in PA examinations, while on bacteriological examination the main cusative agent, ie. Salmonella Enteritidis was isolated successfully . Drug sensitivity test showed that the pathogen was sensitive to chloramphenicol, baytril, gentamisin, and sulphametoxazole-trimethoprim, and resistant to erythromycin, colistin, streptomycin and kanamycin . On the other hand, pathogenicity test of the isolate showed that all but two chickens which were inoculated orally, were died 24 hours post-inoculation . It was concluded that young broiler chickens of the farm were infected by Salmonella Enteritidis.

  7. Comparative Study of Different Methods for the Prediction of Drug-Polymer Solubility

    DEFF Research Database (Denmark)

    Knopp, Matthias Manne; Tajber, Lidia; Tian, Yiwei;

    2015-01-01

    In this study, a comparison of different methods to predict drug-polymer solubility was carried out on binary systems consisting of five model drugs (paracetamol, chloramphenicol, celecoxib, indomethacin, and felodipine) and polyvinylpyrrolidone/vinyl acetate copolymers (PVP/VA) of different...... monomer weight ratios. The drug-polymer solubility at 25 °C was predicted using the Flory-Huggins model, from data obtained at elevated temperature using thermal analysis methods based on the recrystallization of a supersaturated amorphous solid dispersion and two variations of the melting point...... depression method. These predictions were compared with the solubility in the low molecular weight liquid analogues of the PVP/VA copolymer (N-vinylpyrrolidone and vinyl acetate). The predicted solubilities at 25 °C varied considerably depending on the method used. However, the three thermal analysis methods...

  8. Clonal occurrence of Salmonella Weltevreden in cultured shrimp in the Mekong Delta, Vietnam

    DEFF Research Database (Denmark)

    Uddin, Gazi Md Noor; Larsen, Marianne Halberg; Barco, Lisa;

    2015-01-01

    yielding S. Agona, with no difference in Salmonella occurrence between the two production systems. Pulsed field gel electrophoresis (PFGE) of S. Weltevreden showed closely related XbaI pulse types, suggesting a clonal relationship despite the farms and shrimp samples being epidemiologically unrelated. S......This study investigated the occurrence, serovar and antimicrobial resistance of Salmonella spp. in shrimp samples from intensive and extensive farms located in three different provinces in the Mekong Delta, Vietnam. Shrimp from 11 of the 48 farms all contained S. Weltevreden, except for one farm....... Weltevreden was susceptible to most antimicrobials tested, with a few strains being resistant to florfenicol, chloramphenicol, sulfamethoxazole or trimethoprim. Future studies of the ecology of S. Weltevreden should establish if this serovar may survive better and even multiply in warm-water shrimp farm...

  9. Micellar modified spectrophotometric determination of nitrobenzenes based upon reduction with tin(II), diazotisation and coupling with the Bratton-Marshall reagent.

    Science.gov (United States)

    Escrig-Tena, I; Alvarez Rodríguez, L; Esteve-Romero, J; García-Alvarez-Coque, M C

    1998-09-01

    Nitrobenzenes, such as the antibiotic chloramphenicol, the vasodilator nicardipine, and the herbicides dinitramin, dinobuton, fenitrothion, methylparathion, oxyfluorfen, parathion, pendimethalin, quintozene, and trifluralin, were determined by using a spectrophotometric method in the visible region (540 nm). The method was based on the reduction of the nitrobenzenes to arylamines with tin(II) chloride, diazotisation of the arylamines and coupling of the diazonium ions with the Bratton-Marshall reagent. The two latter reactions were performed in a micellar medium of sodium dodecyl sulphate. The linear calibration range was 2x10(-6) to 7x10(-5) M (r>0.999), with limits of detection in the 10(-7) M level, which is 2-6 fold lower with respect to the corresponding spectrophotometric procedure in non-micellar medium. The procedure was applied to the analysis of the compounds in commercial preparations (pharmaceuticals and herbicide formulations) and in water samples, with good recoveries. PMID:18967301

  10. Clindamycin and gentamicin for aerobic and anaerobic sepsis.

    Science.gov (United States)

    Fass, R J; Ruiz, D E; Gardner, W G; Rotilie, C A

    1977-01-01

    Thirty-eight adult patients with serious pleuropulmonary, soft-tissue, bone, and intra-abdominal infections caused by combinations of aerobic, facultative, and anaerobic bacteria were treated with parenterally given clindamycin phosphate and gentamicin sulfate and surgery when appropriate. Nine had associated bacteremia. In 29, infections failed to respond to other therapeutic regimens, which included penicillins, cephalosporins, aminoglycosides, and chloramphenicol. Results with clindamycin and gentamicin were excellent and were attributed primarily to the activity of clindamycin against anaerobes, particularly Bacteroides fragilis. Serum concentrations of clindamycin surpassed by manyfold the minimal inhibitory concentrations (MICs) for anaerobes. Serum concentrations of gentamicin did not consistently surpass the MICs for Enterobacteriaceae and Pseudomonas aeruginosa, although those organisms were consistently gentamicinsusceptible by disk diffusion susceptibility tests. Persistent colonization with Enterobacteriaceae, P aeruginosa, enterococci, or Candida were common, and occasionally they were significant in prolonging the clinical courses of patients with extensive infections. PMID:318824

  11. [Sensitivity of anaerobic bacteria to therapeutic agents (Zurich 1984)].

    Science.gov (United States)

    Wüst, J; Hardegger, U

    1985-12-28

    There are several reports in the literature on resistance of anaerobic bacteria against antimicrobial agents. Therefore, 231 anaerobic strains of various bacterial genera, isolated from clinical specimens during fall 1984, were tested for susceptibility to antimicrobial agents active against anaerobic bacteria. Whereas 23% of the Bacteroides species not belonging to the B. fragilis group were resistant to penicillin, the anaerobic bacteria were still susceptible to chloramphenicol, clindamycin and the nitroimidazoles. The resistance rate against the various new beta-lactam antibiotics was comparable to results of other studies. Due to the increasing resistance it is recommended that the susceptibility of clinically important anaerobes be tested by appropriate techniques. The agar diffusion test must not be used due to unreliable results. Instead, the minimal inhibitory concentration should be determined or the "broth-disk" test performed. PMID:4089587

  12. Disk susceptibility testing of slow-growing anaerobic bacteria.

    Science.gov (United States)

    Kwok, Y Y; Tally, F P; Sutter, V L; Finegold, S M

    1975-01-01

    The susceptibility of 55 strains of slow-growing anaerobes to eight clinically useful or potentially useful antibiotics was determined by agar dilution and disk diffusion tests. Strains of the genera Peptococcus, Peptostreptococcus, Megasphaera, Veillonella, Eubacterium, Bifidobacterium, Clostridium, and Fusobacterium were included. All strains were susceptible to chloramphenicol, but varied in their susceptibility to penicillin, lincomycin, clindamycin, tetracyclines, and vancomycin. Correlation between minimal inhibitory concentration and inhibition zone diameters was generally good. Prediction of susceptibility based on zone diameter measurements appeared satisfactory. Although routine susceptibility testing of anaerobic bacteria is not recommended, there are circumstances where such testing is relevant to the clinical situation. For those laboratories ill-equipped to do dilution tests, a disk diffusion test would give relatively accurate preliminary information. Quantitative susceptibility tests could then be done by a reference laboratory. PMID:1137353

  13. Evidence that thermoinhibition and the alleviation thereof by oxygen plus kinetin in Great Lakes lettuce seed is related to mitochondrial function

    Directory of Open Access Journals (Sweden)

    J. G. C. Small

    1996-07-01

    Full Text Available Thermoinhibition of Lactuca sativa L.cv. Great Lakes 659 seeds occurred at 36 ˚C. Thermoinhibition was alleviated by a combi­nation of 100% O₂ and kinetin (10 mg dm⁻³. Chloramphenicol nullified the effect of O₂ plus kinetin. A number of mitochondrial activities (respiration, coupling, certain matrix enzyme activities and incorporation of [³⁵S]- methionine in mitochondrial proteins were lower in thermoinhibited than in seeds imbibed at 25 ˚C. Treating seeds with plus kinetin at 36 °C restored these mitochondrial activities to the same or in some cases, to higher levels than in 25 °C control seeds.

  14. Topical antibiotics in the management of corneal ulcer

    Directory of Open Access Journals (Sweden)

    Reddy P

    1988-01-01

    Full Text Available A total of 82 patients suffering from corneal ulcer were treated with framycetin 0.5%, gentamicin 3 mg./ml, chloramphenicol 0.4% and a neomycin combination containing Polymixin B sulphate 5000 u, neomycin sulphate 1700 u and gramicidin 0.025 mg/mL in a Randomised comparative study. The commonest organism isolated was Staphylococcus followed by Pneumococcus, Streptococcus and Pseudomonas. The in vitro sensitivity of these isolates to framycetin was higher than that to others Framycetin produced both earlier and a greater degree of improvement in mean score of signs and symptoms than the other antibiotics. It can thus be concluded that framycetin has a better profile of antibacterial activity and clinical efficacy than some other commonly used topical antibiotics in the treatment of corneal ulcer.

  15. Bacterial strains isolated from eggs and their resistance to currently used antibiotics: is there a health hazard for consumers?

    Science.gov (United States)

    Papadopoulou, C; Dimitriou, D; Levidiotou, S; Gessouli, H; Panagiou, A; Golegou, S; Antoniades, G

    1997-01-01

    In order to study the putative transfer of antibiotic resistance from poultry to humans, hens' eggs were examined for the presence of various pathogens. Staphylococcus, Enterobacter, Escherichia, Proteus and Pseudomonas spp. were the most frequently isolated genera. Sensitivity tests, performed with the Kirby-Bauer technique, showed the presence of resistant strains of Staphylococcus aureus (to penicillin-G, tetracycline, erythromycin, clindamycin, cefalosporins, oxacillin, gentamycin, chloramphenicol and tobramycin), Enterococcus faecalis (to ampicillin, ciprofloxacin, clindamycin, gentamycin and tetracyclin), Escherichia coli (to tetracycline, erythromycin, ampicillin and cefalosporins), Enterobacter cloacae (to ampicillin, amoxycillin plus clavunalic acid, erythromycin and tetracycline), Pseudomonas stutzeri (to erythromycin and chlorampenicol) and Citrobacter freundii (to ampicillin, amoxycillin plus clavunalic acid, cefalosporins and co-trimoxazole). PMID:9023039

  16. Antimicrobial activity of essential oil of Eucalyptus globulus against fish pathogenic bacteria

    Science.gov (United States)

    Park, Joon-Woo; Wendt, Mitchell

    2016-01-01

    The antibacterial activities of the essential oil of Eucalyptus globulus (EOEG) was determined against 7 fish pathogenic bacteria (Edwardsiella tarda, Streptococcus iniae, S. parauberis, Lactococcus garviae, Vibrio harveyi, V. ichthyoenteri and Photobacterium damselae) obtained from farmed olive flounder. The inhibitory activity was evaluated by three methods: Disc diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). According to the disc diffusion test, as the concentration of EOEG (5-40 µg) rises, the inhibitory zone increases in size. Compared with amoxicillin, tetracycline and chloramphenicol, EOEG showed similar antibacterial activity. The MIC of EOEG ranged from 7.8 to 125 mg/mL and MBC values ranged from 62 to 250 mg/mL. These results show that EOEG has antimicrobial activity against all seven bacteria, but there was no marked difference between each genus. From these results, it is suggested that EOEG can be used as an antimicrobial agent against fish bacterial diseases in the fish industry.

  17. Nutrient-dependent methylation of a membrane-associated protein of Escherichia coli

    International Nuclear Information System (INIS)

    Starvation of a mid-log-phase culture of Escherichia coli B/r for nitrogen, phosphate, or carbon resulted in methylation of a membrane-associated protein of about 43,000 daltons (P-43) in the presence of chloramphenicol and [methyl-3H]methionine. The in vivo methylation reaction occurred with a doubling time of 2 to 5 min and was followed by a slower demethylation process. Addition of the missing nutrient to a starving culture immediately prevented further methylation of P-43. P-43 methylation is not related to the methylated chemotaxis proteins because P-43 is methylated in response to a different spectrum of nutrients and because P-43 is methylated on lysine residues. The characteristics of P-43 are similar to those of a methylated protein previously described in Bacillus subtilis and B. licheniformis and are consistent with the proposal that methylation of this protein functions in nutrient sensing

  18. Plasmid-Encoded Multidrug Resistance of Salmonella typhi and some Enteric Bacteria in and around Kolkata, India: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Nishith Kumar Pal

    2005-02-01

    Full Text Available The present study investigates the occurrence of R-plasmid in Salmonella typhi isolates from enteric fever cases in and around Kolkata (1991-2001, India following in vitro conjugation experiments, isolation of plasmid DNAs and agarose gel electrophoretic analysis. The multidrug resistant (MDR S. typhi strains contained a transferable plasmid conferring resistance to ampicillin, chloramphenicol, cotrimoxazole and tetracycline. The plasmid encoding ACCoT-resistance of Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris were conjugative and co-migrated with the plasmid of MDR S. typhi isolates. The antibiotic sensitive S. typhi isolates did not contain any plasmid. Thus the findings of the present study confirmed the instability of the R-plasmid in S. typhi, and that the antibiotic sensitive S. typhi strains acquired the R-plasmid from other enteric bacteria such as E. coli, K. pneumoniae and P.vulgaris to undergo a suitable adaptation for survival in the changing antibiotic environment.

  19. Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat

    International Nuclear Information System (INIS)

    Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, the authors demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBV gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses

  20. Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Sigrid Mayrhofer

    2011-01-01

    Full Text Available Strains of the genus Bifidobacterium are frequently used as probiotics, for which the absence of acquired antimicrobial resistance has become an important safety criterion. This clarifies the need for antibiotic susceptibility data for bifidobacteria. Based on a recently published standard for antimicrobial susceptibility testing of bifidobacteria with broth microdilution method, the range of susceptibility to selected antibiotics in 117 animal bifidobacterial strains was examined. Narrow unimodal MIC distributions either situated at the low-end (chloramphenicol, linezolid, and quinupristin/dalfopristin or high-end (kanamycin, neomycin concentration range could be detected. In contrast, the MIC distribution of trimethoprim was multimodal. Data derived from this study can be used as a basis for reviewing or verifying present microbiological breakpoints suggested by regulatory agencies to assess the safety of these micro-organisms intended for the use in probiotics.