Sample records for nalidixic acid tetracycline

  1. Resistance of Pseudomonas aeruginosa PAO to nalidixic acid and low levels of beta-lactam antibiotics: mapping of chromosomal genes.

    PubMed Central

    Rella, M; Haas, D

    1982-01-01

    Resistance to high concentrations of nalidixic acid in Pseudomonas aeruginosa PAO was due to mutations in one locus designated nalA, which was mapped by transduction between hex-9001 and leu-10. The nalA mutants were cross-resistant to pipemidic acid, a nalidixic acid analog, at relatively low concentrations. Replicative DNA synthesis was resistant to both drugs in permeabilized cells of nalA mutants. A locus coding for low-level resistance to nalidixic acid, nalB, was cotransducible with pyrB, proC, and met-28. The nalB mutants were also resistant to low levels of pipemidic acid, novobiocin, and beta-lactam antibiotics (e.g., carbenicillin, azlocillin, and cefsulodin), but not to other drugs, such as gentamicin, rifampin, kanamycin, or tetracycline. In nalB mutants, DNA replication showed wild-type sensitivity to nalidixic acid, whereas carbenicillin-induced filamentation required higher drug levels than in the wild-type strain. Thus, nalB mutations appear to decrease cell permeability to some antibiotics. The sensitivity of replicative DNA synthesis to nalidixic acid and novobiocin was very similar in P. aeruginosa and Escherichia coli; by contrast, the concentrations of these drugs needed to inhibit growth of P. aeruginosa were higher than those reported for E. coli by one or two orders of magnitude. PMID:6821455

  2. Antibacterial Efficacy of Dihydroxylated Chalcones in Binary and Ternary Combinations with Nalidixic Acid and Nalidix Acid-Rutin Against Escherichia coli ATCC 25 922.

    PubMed

    Talia, Juan Manuel; Tonn, Carlos Eugenio; Debattista, Nora Beatriz; Pappano, Nora Beatriz

    2012-12-01

    In order to determine the existence of synergism, the bacteriostatic action of flavonoids against Escherichia coli ATCC 25 922 between dihydroxylated chalcones and a clinically interesting conventional antibiotic, binary combinations of 2',3-dihydroxychalcone, 2',4-dihydroxychalcone and 2',4'-dihydroxychalcone with nalidixic acid and its ternary combinations with rutin (inactive flavonoid) were assayed against this Gram negative bacterium. Using a kinetic-turbidimetric method, growth kinetics were monitored in broths containing variable amounts of dihydroxychalcone alone, combinations of dihydroxychalcone variable concentration-nalidixic acid constant concentration and dihydroxychalcone variable concentration-nalidixic acid constant concentration-rutin constant concentration, respectively. The minimum inhibitory concentrations of dihydroxychalcones alone and its binary and ternary combinations were evaluated. All chalcones, and their binary and ternary combinations showed antibacterial activity, being rutin an excellent synergizing for the dihydroxychalcone-nalidixic acid binary combination against E. coli ATCC 25 922. Thus, this synergistic effect is an important way that could lead to the development of new combination antibiotics against infections caused by E. coli.

  3. Comparison of norfloxacin versus nalidixic acid in therapy of acute urinary tract infections

    PubMed Central

    Selin, Liisa K; Harding, Godfrey KM; Thomson, Margaret J; Kennedy, James K; Urias, Barbara A; Ronald, Allan R

    1990-01-01

    Thirty-seven adult patients with acute urinary tract infections (UTI) were randomized to receive either a seven day (lower UTI) or a 14 day (upper UTI) course of norfloxacin 400 mg orally twice daily, or nalidixic acid 1 g orally four times per day. Mean age, underlying disease and infecting organisms were similar in the two groups. Nine patients in the norfloxacin group and seven in the nalidixic acid group had presumptive evidence of upper UTI. Overall, 12 patients had antibody-coated bacteria-positive infections. The infecting organisms were: Escherichia coli (27), coagulase-negative staphylococci (four), Citrobacter freundii (three), Klebsiella pneumoniae (three), and Proteus mirabilis, Proteus vulgaris, Pseudomonas aeruginosa, Enterobacter agglomerans, Streptococcus agalactiae, Enterococcus faecalis (one of each). All of the organisms were susceptible to norfloxacin, while 81% were susceptible to nalidixic acid. The effects on the periurethral and anal canal flora were similar in both groups. Five patients in each group experienced adverse clinical effects. The cure rates for norfloxacin and nalidixic acid were 79 and 83%, respectively. There were two failures, two relapses and four reinfections in the norfloxacin group. In the nalidixic acid group, there were two failures, one relapse and four reinfections. One of the failure patients in the nalidixic acid group developed resistance to the drug, and two of the four reinfections were due to organisms resistant to nalidixic acid. In this patient population it was concluded that nalidixic acid may be as effective as norfloxacin in the treatment of acute, symptomatic UTI. PMID:22553437

  4. New Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Inhibitors, Nalidixic Acid Linked to Isatin Schiff Bases via Certain l-Amino Acid Bridges.

    PubMed

    Naglah, Ahmed M; Ahmed, Atallah F; Wen, Zhi-Hong; Al-Omar, Mohamed A; Amr, Abd El-Galil E; Kalmouch, Atef

    2016-04-15

    A series of new Schiff bases were synthesized by condensation of isatins with the nalidixic acid-l-amino acid hydrazides. Prior to hydrazide formation, a peptide linkage has been prepared via coupling of nalidixic acid with appropriate l-amino acid methyl esters to yield 3a-c. The chemical structures of the new Schiff bases (5b and 5d-h) were confirmed by means of IR, NMR, mass spectroscopic, and elemental analyses. The anti-inflammatory activity of these Schiff bases was evaluated via measurement of the expressed inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells model. The Schiff bases exhibited significant dual inhibitory effect against the induction of the pro-inflammatory iNOS and COX-2 proteins with variable potencies. However, they strongly down-regulated the iNOS expression to the level of 16.5% ± 7.4%-42.2% ± 19.6% compared to the effect on COX-2 expression (<56.4% ± 3.1% inhibition) at the same concentration (10 μM). The higher iNOS inhibition activity of the tested Schiff bases, relative to that of COX-2, seems to be a reflection of the combined suppressive effects exerted by their nalidixic acid, isatins (4a-c), and l-amino acid moieties against iNOS expression. These synthesized nalidixic acid-l-amino acid-isatin conjugates can be regarded as a novel class of anti-inflammatory antibacterial agents.

  5. A flow injection chemiluminescence method for determination of nalidixic acid based on KMnO₄-morin sensitized with CdS quantum dots.

    PubMed

    Khataee, Alireza; Lotfi, Roya; Hasanzadeh, Aliyeh; Iranifam, Mortaza; Joo, Sang Woo

    2016-02-05

    A simple and sensitive flow injection chemiluminescence (CL) method was developed for determination of nalidixic acid by application of CdS quantum dots (QDs) in KMnO4-morin CL system in acidic medium. Optical and structural features of L-cysteine capped CdS quantum dots which were synthesized via hydrothermal approach were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and ultraviolet-visible (UV-Vis) spectroscopy. Moreover, the potential mechanism of the proposed CL method was described using the results of the kinetic curves of CL systems, the spectra of CL, PL and UV-Vis analyses. The CL intensity of the KMnO4-morin-CdS QDs system was considerably increased in the presence of nalidixic acid. Under the optimum condition, the enhanced CL intensity was linearly proportional to the concentration of nalidixic acid in the range of 0.0013 to 21.0 mg L(-1), with a detection limit of (3σ) 0.003 mg L(-1). Also, the proposed CL method was utilized for determination of nalidixic acid in environmental water samples, and commercial pharmaceutical formulation to approve its applicability. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) method was utilized for determination of nalidixic acid and the results of real sample analysis by two proposed methods were compared. Comparison the analytical features of these methods represented that the proposed CL method is preferable to CD-IMS method for determination of nalidixic acid due to its high sensitivity and precision. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. A Randomized Controlled Comparison of Azithromycin and Ofloxacin for Treatment of Multidrug-Resistant or Nalidixic Acid-Resistant Enteric Fever

    PubMed Central

    Chinh, Nguyen Tran; Parry, Christopher M.; Ly, Nguyen Thi; Ha, Huynh Duy; Thong, Mai Xuan; Diep, To Song; Wain, John; White, Nicholas J.; Farrar, Jeremy J.

    2000-01-01

    To examine the efficacy and safety of short courses of azithromycin and ofloxacin for treating multidrug-resistant (MDR, i.e., resistant to chloramphenicol, ampicillin, and cotrimoxazole) and nalidixic acid-resistant enteric fever, azithromycin (1 g once daily for 5 days at 20 mg/kg/day) and ofloxacin (200 mg orally twice a day for 5 days at 8 mg/kg/day) were compared in an open randomized study in adults admitted to a hospital with uncomplicated enteric fever. A total of 88 blood culture-confirmed patients were enrolled in the study (86 with Salmonella enterica serovar Typhi and 2 with S. enterica serovar Paratyphi A). Of these, 44 received azithromycin and 44 ofloxacin. A total of 68 of 87 (78%) isolates were MDR serovar Typhi, and 46 of 87 (53%) were nalidixic acid resistant. The MIC90 (range) of azithromycin was 8 (4 to 16) μg/ml for the isolates. The MIC90 (range) of ofloxacin for the nalidixic acid-sensitive isolates was 0.03 (0.015 to 0.06) μg/ml and for the nalidixic acid-resistant isolates it was 0.5 (0.25 to 1.0) μg/ml. There was no significant difference in the overall clinical cure rate with ofloxacin and azithromycin (38 of 44 [86.4%] versus 42 of 44 [95.5%]; P = 0.27) or in the patients infected with nalidixic acid-resistant typhoid (17 of 21 [81.0%] versus 24 of 25 [96.0%]; P = 0.16). However, patients with nalidixic acid-resistant typhoid treated with ofloxacin had a longer fever clearance time compared with those treated with azithromycin (174 [60 to 264] versus 135 [72 to 186] h; P = 0.004) and had positive fecal cultures after the end of treatment (7 of 17 [41%] versus 0 of 19 [0%]; P = 0.002). Both antibiotics were well tolerated. A 5-day course of azithromycin was effective for the treatment of enteric fever due to MDR and nalidixic-acid-resistant serovar Typhi, whereas the ofloxacin regimen chosen was less satisfactory for these strains. PMID:10858343

  7. Sorption and transport of acetaminophen, 17alpha-ethynyl estradiol, nalidixic acid with low organic content aquifer sand.

    PubMed

    Lorphensri, Oranuj; Sabatini, David A; Kibbey, Tohren C G; Osathaphan, Khemarath; Saiwan, Chintana

    2007-05-01

    The sorption and transport of three pharmaceutical compounds (acetaminophen, an analgesic; nalidixic acid, an antibiotic; and 17alpha-ethynyl estradiol, a synthetic hormone) were examined by batch sorption experiments and solute displacement in columns of silica, alumina, and low organic carbon aquifer sand at neutral pH. Silica and alumina were used to represent negatively-charged and positively-charged fractions of subsurface media. Column transport experiments were also conducted at pH values of 4.3, 6.2, and 8.2 for the ionizable nalidixic acid. The computer program UFBTC was used to fit the breakthrough data under equilibrium and nonequilibrium conditions with linear/nonlinear sorption. Good agreement was observed between the retardation factors derived from column model studies and estimated from equilibrium batch sorption studies. The sorption and transport of nalidixic acid was observed to be highly pH dependent, especially when the pH was near the pK(a) of nalidixic acid (5.95). Thus, near a compound's pK(a) it is especially important that the batch studies be performed at the same pH as the column experiment. While for ionic pharmaceuticals, ion exchange to oppositely-charged surfaces, appears to be the dominant adsorption mechanism, for neutral pharmaceuticals (i.e., acetaminophen, 17alpha-ethynyl estradiol) the sorption correlated well with the K(ow) of the pharmaceuticals, suggesting hydrophobically motivated sorption as the dominant mechanism.

  8. A flow injection chemiluminescence method for determination of nalidixic acid based on KMnO4-morin sensitized with CdS quantum dots

    NASA Astrophysics Data System (ADS)

    Khataee, Alireza; Lotfi, Roya; Hasanzadeh, Aliyeh; Iranifam, Mortaza; Joo, Sang Woo

    2016-02-01

    A simple and sensitive flow injection chemiluminescence (CL) method was developed for determination of nalidixic acid by application of CdS quantum dots (QDs) in KMnO4-morin CL system in acidic medium. Optical and structural features of L-cysteine capped CdS quantum dots which were synthesized via hydrothermal approach were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and ultraviolet-visible (UV-Vis) spectroscopy. Moreover, the potential mechanism of the proposed CL method was described using the results of the kinetic curves of CL systems, the spectra of CL, PL and UV-Vis analyses. The CL intensity of the KMnO4-morin-CdS QDs system was considerably increased in the presence of nalidixic acid. Under the optimum condition, the enhanced CL intensity was linearly proportional to the concentration of nalidixic acid in the range of 0.0013 to 21.0 mg L- 1, with a detection limit of (3σ) 0.003 mg L- 1. Also, the proposed CL method was utilized for determination of nalidixic acid in environmental water samples, and commercial pharmaceutical formulation to approve its applicability. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) method was utilized for determination of nalidixic acid and the results of real sample analysis by two proposed methods were compared. Comparison the analytical features of these methods represented that the proposed CL method is preferable to CD-IMS method for determination of nalidixic acid due to its high sensitivity and precision.

  9. Enhancement by Nalidixic Acid of the Thermal Susceptibility of the Ts-7 Mutant of Escherichia Coli TAU-Bar

    PubMed Central

    Nishida, Mikio; Mishima, Yukio; Kawada, Jun; Yielding, K. Lemone

    1975-01-01

    Nadilidixic acid at 5 × 10−6 M produced a substantial increase in thermal susceptibility of Ts-7, suggesting either that the thermal and nalidixic acid targets are identical or closely interdependent. PMID:1101825

  10. EFFECT OF TETRACYCLINES ON THE INTRACELLULAR AMINO ACIDS OF MOLDS

    PubMed Central

    Freeman, Bob A.; Circo, Richard

    1963-01-01

    Freeman, Bob A. (University of Chicago, Chicago, Ill.) and Richard Circo. Effect of tetracyclines on the intracellular amino acids of molds. J. Bacteriol. 86:38–44. 1963.—The tetracycline antibiotics were shown to alter the amino acid metabolism of molds whose growth is not markedly affected. Eight molds were grown in the presence of these antiobiotics; four exhibited a general reduction in the concentration of the intracellular amino acids, except for glutamic acid and alanine. In most of these four cultures, the tetracyclines also caused the complete disappearance of arginine, lysine, proline, phenylalanine, and tyrosine from the intracellular amino acid pool. The significance of these observations and the usefulness of the method in the study of the mechanisms of antibiotic action are discussed. PMID:14051820

  11. Novel gyrA point mutation in a strain of Escherichia coli resistant to fluoroquinolones but not to nalidixic acid.

    PubMed

    Cambau, E; Bordon, F; Collatz, E; Gutmann, L

    1993-06-01

    We have previously described a clinical isolate of Escherichia coli (Q2) that is highly resistant to fluoroquinolones (MIC of ciprofloxacin, 16 micrograms/ml) but susceptible to nalidixic acid (MIC of nalidixic acid, 4 micrograms/ml) (N. Moniot-Ville, J. Guibert, N. Moreau, J.F. Acar, E. Collatz, and L. Gutmann, Antimicrob. Agents Chemother. 35:519-523, 1991). Transformation of strain Q2 with a plasmid carrying the wild-type gyrA gene from E. coli K-12(pAFF801) resulted in a 32-fold decrease in the MIC of ciprofloxacin, suggesting that at least one mutation in gyrA was involved in the resistance of Q2. Intragenic gyrA fragments of 668 and 2,500 bp from strain Q2 were amplified by the polymerase chain reaction. We sequenced the 668-bp fragment and identified a single novel point mutation (transition from G to A at position 242), leading to an amino acid substitution (Gly-81 to Asp) in the gyrase A subunit. We constructed hybrid plasmids by substituting either the 668-bp fragment or the 2,500-bp fragment from Q2 DNA, both of which contained the gyrA point mutation, for the corresponding fragments in wild-type gyrA (2,625 bp) of E. coli K-12. When introduced into E. coli KNK453 (gyrA temperature sensitive), both plasmids conferred an eightfold increase in the MIC of ciprofloxacin, but only a twofold increase in the MIC of nalidixic acid. When introduced into E. coli Q2, neither plasmid conferred any change in the MICs of ciprofloxacin or nalidixic acid, suggesting that only the point mutation found in gyrA was involved in the resistance that we observed.

  12. DNA injection and genetic recombination of alkylated bacteriophage T7 in the presence of nalidixic acid.

    PubMed Central

    Karska-Wysocki, B; Mamet-Bratley, M D; Przewlocki, G

    1977-01-01

    Marker rescue experiments with alkylated T7 bacteriophage carried out in the presence and in the absence of nalidixic acid suggest that the gradient in rescue is due to two alkylation-induced causes: a DNA injection defect and an interference with DNA synthesis. PMID:916036

  13. Synthesis, spectroscopic characterizations, crystal structures and DFT studies of nalidixic acid carbonyl hydrazones derivatives

    NASA Astrophysics Data System (ADS)

    Bergamini, F. R. G.; Ribeiro, M. A.; Lancellotti, M.; Machado, D.; Miranda, P. C. M. L.; Cuin, A.; Formiga, A. L. B.; Corbi, P. P.

    2016-09-01

    This article describes the synthesis and characterization of the 1-ethyl-7-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carbohydrazide (hzd) and six carbonyl hydrazones derivatives of the nalidixic with 1H-pyrrol-2-ylmethylidene (hpyrr), 1H-imidazol-2-ylmethylidene (h2imi), pyridin-2-ylmethylidene (h2py), pyridin-3-ylmethylidene (h3py), pyridin-4-ylmethylidene(h4py) and (2-hydroxyphenyl)methylidene (hsali). The carbonyl hydrazones were characterized by elemental and ESI-QTOF-MS analyses, IR and detailed NMR spectroscopic measurements. The 2D NMR experiments allowed the unambiguous assignment of the hydrogen, carbon and nitrogen atoms, which have not been reported for nalidixic acid carbonyl hydrazone derivatives so far. Crystal structures of hzd and the new carbonyl hydrazones h2imi, hpyrr and h3py were determined by X-ray diffraction studies. Although the synthesis of hzd was reported decades ago, the hzd crystal structure have not been reported yet. Geometric optimizations of all the characterized structures were performed with the aid of DFT studies. Despite the fact that the hydrazones with 2-pyridine carboxylic acid (h2py) and salicyl aldehyde (hsali) were already reported by literature, a detailed spectroscopic study followed by DFT studies are also reported for such compounds in this manuscript. Antimicrobial studies of the compounds are also presented.

  14. Clarithromycin and tetracycline binding to soil humic acid in the absence and presence of calcium

    NASA Astrophysics Data System (ADS)

    Christl, Iso; Ruiz, Mercedes; Schmidt, J. R.; Pedersen, Joel A.

    2017-04-01

    Many organic micropollutants including antibiotics contain positively charged moieties and are present as organic cations or zwitterions at environmentally relevant pH conditions. In this study, we investigated the pH-, ionic strength-, and concentration-dependent binding of the two antibiotics clarithromycin and tetracycline to dissolved humic acid in the absence and presence of Ca2+. The investigated compounds strongly differ in their chemical speciation. Clarithromycin can be present as neutral and cationic species, only. But tetracycline can form cations, zwitterions as well as anions and is able to form various calcium complexes. The pH-dependence of binding to soil humic acid was observed to be strongly linked to the protonation behavior for both antibiotics. The presence of Ca2+ decreased clarithromycin binding to soil humic acid, but increased tetracycline binding with increasing Ca2+ concentration. The experimental observations were well described with the NICA-Donnan model considering the complete aqueous speciation of antibiotics and allowing for binding of cationic and zwitterionic species to soil humic acid. Our results indicate that clarithromycin is subject to competition with Ca2+ for binding to soil humic acid and that the electrostatic interaction of positively charged tetracycline-Ca complexes with humic acid enhances tetracycline binding in presence of Ca2+ rather than the formation of ternary complexes, except at very low tetracycline concentrations. We conclude that for the description of ionizable organic micropollutant binding to dissolved natural organic matter, the complete speciation of both sorbate and sorbent has to be considered.

  15. Clarithromycin and Tetracycline Binding to Soil Humic Acid in the Absence and Presence of Calcium.

    PubMed

    Christl, Iso; Ruiz, Mercedes; Schmidt, J R; Pedersen, Joel A

    2016-09-20

    Numerous ionizable organic micropollutants contain positively charged moieties at pH values typical of environmental systems. Describing organic cation and zwitterion interaction with dissolved natural organic matter requires explicit consideration of the pH-dependent speciation of both sorbate and sorbent. We studied the pH-, ionic strength-, and concentration-dependent binding of relatively large, organic cations and zwitterions (viz., the antibiotics clarithromycin and tetracycline) to dissolved humic acid in the absence and presence of Ca(2+) and evaluated the ability of the NICA-Donnan model to describe the data. Clarithromycin interaction with dissolved humic acid was well described by the model including the competitive effect of Ca(2+) on clarithromycin binding over a wide range of solution conditions by considering only the binding of the cationic species to low proton-affinity sites in humic acid. Tetracycline possesses multiple ionizable moieties and forms complexes with Ca(2+). An excellent fit to experimental data was achieved by considering tetracycline cation interaction with both low and high proton-affinity sites of humic acid and zwitterion interaction with high proton-affinity sites. In contrast to clarithromycin, tetracycline binding to humic acid increased in the presence of Ca(2+), especially under alkaline conditions. Model calculations indicate that this increase is due to electrostatic interaction of positively charged tetracycline-Ca complexes with humic acid rather than due to the formation of ternary complexes, except at very low TC concentrations.

  16. Tetracycline adsorption on kaolinite: pH, metal cations and humic acid effects.

    PubMed

    Zhao, Yanping; Geng, Jinju; Wang, Xiaorong; Gu, Xueyuan; Gao, Shixiang

    2011-07-01

    Contamination of environmental matrixes by human and animal wastes containing antibiotics is a growing health concern. Because tetracycline is one of the most widely-used antibiotics in the world, it is important to understand the factors that influence its mobility in soils. This study investigated the effects of pH, background electrolyte cations (Li(+), Na(+), K(+), Ca(2+) and Mg(2+)), heavy metal Cu(2+) and humic acid (HA) on tetracycline adsorption onto kaolinite. Results showed that tetracycline was greatly adsorbed by kaolinite over pH 3-6, then decreased with the increase of pH, indicating that tetracycline adsorption mainly through ion exchange of cations species and complexation of zwitterions species. In the presence of five types of cations (Li(+), Na(+), K(+), Ca(2+) and Mg(2+)), tetracycline adsorption decreased in accordance with the increasing of atomic radius and valence of metal cations, which suggested that outer-sphere complexes formed between tetracycline and kaolinite, and the existence of competitor ions lead to the decreasing adsorption. The presence of Cu(2+) greatly enhanced the adsorption probably by acting as a bridge ion between tetracycline species and the edge sites of kaolinite. HA also showed a major effect on the adsorption: at pH < 6, the presence of HA increased the adsorption, while the addition of HA showed little effect on tetracycline adsorption at higher pH. The soil environmental conditions, like pH, metal cations and soil organic matter, strongly influence the adsorption behavior of tetracycline onto kaolinite and need to be considered when assessing the environmental toxicity of tetracycline.

  17. Enthalpy-entropy compensation for the solubility of drugs in solvent mixtures: paracetamol, acetanilide, and nalidixic acid in dioxane-water.

    PubMed

    Bustamante, P; Romero, S; Pena, A; Escalera, B; Reillo, A

    1998-12-01

    In earlier work, a nonlinear enthalpy-entropy compensation was observed for the solubility of phenacetin in dioxane-water mixtures. This effect had not been earlier reported for the solubility of drugs in solvent mixtures. To gain insight into the compensation effect, the behavior of the apparent thermodynamic magnitudes for the solubility of paracetamol, acetanilide, and nalidixic acid is studied in this work. The solubility of these drugs was measured at several temperatures in dioxane-water mixtures. DSC analysis was performed on the original powders and on the solid phases after equilibration with the solvent mixture. The thermal properties of the solid phases did not show significant changes. The three drugs display a solubility maximum against the cosolvent ratio. The solubility peaks of acetanilide and nalidixic acid shift to a more polar region at the higher temperatures. Nonlinear van't Hoff plots were observed for nalidixic acid whereas acetanilide and paracetamol show linear behavior at the temperature range studied. The apparent enthalpies of solution are endothermic going through a maximum at 50% dioxane. Two different mechanisms, entropy and enthalpy, are suggested to be the driving forces that increase the solubility of the three drugs. Solubility is entropy controlled at the water-rich region (0-50% dioxane) and enthalpy controlled at the dioxane-rich region (50-100% dioxane). The enthalpy-entropy compensation analysis also suggests that two different mechanisms, dependent on cosolvent ratio, are involved in the solubility enhancement of the three drugs. The plots of deltaH versus deltaG are nonlinear, and the slope changes from positive to negative above 50% dioxane. The compensation effect for the thermodynamic magnitudes of transfer from water to the aqueous mixtures can be described by a common empirical nonlinear relationship, with the exception of paracetamol, which follows a separate linear relationship at dioxane ratios above 50%. The

  18. Radiation survival of two nalidixic acid resistant strains of Salmonella typhimurium in various media

    NASA Astrophysics Data System (ADS)

    Shamsuzzaman, Kazi; Goodwin, Marlene; George, Ian; Singh, Harwant

    Radiation doses required for 90% inactivation, the D10 values, have been determined for two nalidixic acid-resistant strains of Salmonella typhimurium, Nal R ATCC 13311 and K1-2B, in different media. The D10 values were 0.20, 0.57 and 0.53 kGy for the ATCC 13311 strain, and were 0.21, 0.4 and 0.32 kGy for the K1-2B strain, in phosphate buffer, in nutrient broth and on chicken drumsticks, respectively. Since these two strains have radiation sensitivity similar to several Salmonella serotypes reported in the literature, they are good indicator organisms for use in studies on the effect of irradiation on Salmonella in foods that might frequently be contaminated with such organisms.

  19. Nalidixic Acid-Resistant Salmonella enterica Serotype Typhi Presenting as a Primary Psoas Abscess: Case Report and Review of the Literature

    PubMed Central

    Shakespeare, William A.; Davie, Daniel; Tonnerre, Claude; Rubin, Michael A.; Strong, Michael; Petti, Cathy A.

    2005-01-01

    We report an unusual case of Salmonella enterica serotype Typhi presenting as a primary psoas abscess. The isolate tested susceptible to ciprofloxacin but resistant to nalidixic acid in vitro, a pattern associated with fluoroquinolone therapeutic failures. We review the literature for serovar Typhi psoas abscess in the absence of bacteremia and discuss the importance of identifying isolates with reduced susceptibility to fluoroquinolones. PMID:15695728

  20. Toxicity of nalidixic acid on candida albicans, Saccharomyces cerevisiae, and Kluyveromyces lactis.

    PubMed

    Sobieski, R J; Brewer, A R

    1976-03-01

    The antibacterial drug nalidixic acid (Nal) can suppress the growth of Candida albicans at levels of the drug normally found in urine. Growth suppression increases as drug levels are increased, and Nal also causes a similar proportional inhibition of the synthesis of all cellular macromolecules. However, growth temperature (25 versus 37 C) and the divalent cations Mg(2+) and Mn(2+) can increase C. albicans resistance to Nal. Also, nitrogen depletion of Candida shows that Nal-treated and untreated cells exhibit no difference in leucine uptake during readaptation to nitrogen. In Nal-treated, nitrogen-starved cells, ribonucleic acid and deoxyribonucleic acid (DNA) biosynthesis are less affected than in unstarved Nal-treated cells, but of the two nucleic acids DNA synthesis is the most affected. Nal-resistant strains of C. albicans exhibit a slight toxicity for macromolecular synthesis. Nal treatment of a synchronized population of Saccharomyces cerevisiae results in an increase in the culture mean doubling time of, at most, 20%, but Nal causes the loss of synchronous cell division. With a synchronized population of Kluyveromyces lactis, Nal causes an increase in the mean doubling time of upwards of 300%, with synchrony of cell division being maintained. It is known that S. cerevisiae asynchronously synthesizes mitochondrial DNA during the cell cycle, whereas with K. lactis it is synchronous. Thus, with C. albicans Nal toxicity is dependent both on the dose and the physiological state of the cell. Furthermore, Nal inhibits growth of yeast with synchronous mitochondrial DNA synthesis more adversely than yeast with asynchronous mitochondrial DNA synthesis.

  1. Tetracycline removal and effect on the formation and degradation of extracellular polymeric substances and volatile fatty acids in the process of hydrogen fermentation.

    PubMed

    Hou, Guangying; Hao, Xiaoyan; Zhang, Rui; Wang, Jing; Liu, Rutao; Liu, Chunguang

    2016-07-01

    Many research indicate antibiotics show adverse effect on methane fermentation, while few research focus on their effect on hydrogen fermentation. The present study aimed to gain insight of the effect of antibiotics on hydrogen fermentation with waste sludge and corn straw as substrate. For this purpose, tetracycline, as a model, was investigated with regard to tetracycline removal, hydrogen production, interaction with extracellular polymeric substances (EPSs) of substrate and volatile fatty acids (VFAs) on concentration and composition. Results show that tetracycline could be removed efficiently by hydrogen fermentation, and relative low-dose tetracycline (200mg/l) exposure affects little on hydrogen production. While tetracycline exposure could change hydrogen fermentation from butyric acid-type to propionic acid-type depending on tetracycline level. Based upon three-dimensional excitation-emission matrix fluorescence spectroscopy and UV-vis tetracycline changed the component and content of EPSs, and static quenching was the main mechanism between EPSs with tetracycline. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Evaluation of Models Describing the Growth of Nalidixic Acid-Resistant E. coli O157:H7 in Blanched Spinach and Iceberg Lettuce as a Function of Temperature

    PubMed Central

    Kim, Juhui; Chung, Hyunjung; Cho, Joonil; Yoon, Kisun

    2013-01-01

    The aim of this study was to model the growth of nalidixic acid-resistant E. coli O157:H7 (E. coli O157:H7NR) in blanched spinach and to evaluate model performance with an independent set of data for interpolation (8.5, 13, 15 and 27 °C) and for extrapolation (broth and fresh-cut iceberg lettuce) using the ratio method and the acceptable prediction zone method. The lag time (LT), specific growth rate (SGR) and maximum population density (MPD) obtained from each primary model were modeled as a function of temperature (7, 10, 17, 24, 30, and 36 °C) using Davey, square root, and polynomial models, respectively. At 7 °C, the populations of E. coli O157:H7NR increased in tryptic soy broth with nalidixic acid (TSBN), blanched spinach and fresh-cut iceberg lettuce, while the populations of E. coli O157:H7 decreased in TSB after 118 h of LT, indicating the risk of nalidixic acid-resistant strain of E. coli O157:H7 contaminated in ready-to-eat produce at refrigerated temperature. When the LT and SGR models of blanched spinach was extended to iceberg lettuce, all relative errors (percentage of RE = 100%) were inside the acceptable prediction zone and had an acceptable Bf and Af values. Thus, it was concluded that developed secondary models for E. coli O157:H7NR in blanched spinach were suitable for use in making predictions for fresh cut iceberg lettuce, but not for static TSBN in this work. PMID:23839062

  3. Nalidixic acid surrogate test for susceptibility to ciprofloxacin in Salmonella. Revisiting the question.

    PubMed

    Guzmán-Martín, José Luis; Navarro-Marí, José María; Expósito-Ruiz, Manuela; Gutiérrez-Fernández, José

    2018-05-16

    We investigated the reliability of nalidixic acid (NA) susceptibility as a marker of ciprofloxacin susceptibility in Salmonella, analysing 302 stool isolates. NC53 of the MicroScan system was used for NA susceptibility tests and the E-test was used for ciprofloxacin susceptibility tests. Among the isolates, 178 (58.9 %) were serogroup B, 74 (24.5 %) were serogroup D, 27 (8.9 %) were serogroup C and 23 (7.6 %) were from other minor serogroups. Globally, susceptibility to NA correctly predicted the susceptibility of Salmonella to ciprofloxacin, with a sensitivity of 81.5 %, a specificity of 97.6 %, and positive and negative predictive values of 88 and 96 %, respectively. However, there were differences among the serogroups in terms of sensitivity (P<0.001) and positive predictive values (P=0.013). NA is a reliable marker for serogroup D, but not for serogroups B or C. According to these findings, NA susceptibility measured with the MicroScan system can be used as a marker of ciprofloxacin resistance in some serogroups in our setting.

  4. Clinical outcomes of nalidixic acid, ceftriaxone, and multidrug-resistant nontyphoidal salmonella infections compared with pansusceptible infections in FoodNet sites, 2006-2008.

    PubMed

    Krueger, Amy L; Greene, Sharon A; Barzilay, Ezra J; Henao, Olga; Vugia, Duc; Hanna, Samir; Meyer, Stephanie; Smith, Kirk; Pecic, Gary; Hoefer, Dina; Griffin, Patricia M

    2014-05-01

    Nontyphoidal Salmonella causes an estimated 1.2 million infections, 23,000 hospitalizations, and 450 deaths annually in the United States. Most illnesses are self-limited; however, treatment with antimicrobial agents can be life-saving for invasive infections. The Foodborne Diseases Active Surveillance Network and the National Antimicrobial Resistance Monitoring System collaborated on a prospective cohort study of patients with nontyphoidal Salmonella bloodstream and gastrointestinal infections to determine differences in the clinical outcomes of resistant compared with pansusceptible infections. Interviews were conducted within 85 days of specimen collection date. Of 875 nontyphoidal Salmonella isolates, 705 (81%) were pansusceptible, 165 (19%) were resistant to at least 1 agent, and 5 (0.6%) had only intermediate resistance. The most common pattern, found in 51 (31%) of resistant isolates, was resistance to at least ampicillin, chloramphenicol, streptomycin, sulfisoxazole, and tetracycline (ACSSuT); 88% of isolates with this pattern were serotype Typhimurium or Newport. Fourteen (52%) of the 27 ceftriaxone-resistant isolates were also ACSSuT resistant. Adjusted for age and serotype, bloodstream infection was significantly more common among patients infected with strains resistant to only two, only three, or only five antimicrobial classes, to ACSSuT with or without other agents, to ACSSuT only, or to nalidixic acid with or without other agents than among patients with pansusceptible isolates. Adjusted for age, serotype, and bloodstream infection, hospitalization was significantly more common among patients infected with strains resistant to only three agents or to ceftriaxone (all ceftriaxone-resistant isolates were resistant to other agents) than among patients with pansusceptible isolates. This study extends evidence that patients with antimicrobial-resistant nontyphoidal Salmonella infections have more severe outcomes. Prevention efforts are needed to reduce

  5. Emergence and spread of tetracycline resistant Vibrio cholerae O1 El Tor variant during 2010 cholera epidemic in the tribal areas of Odisha, India.

    PubMed

    Kar, Santanu Kumar; Pal, Bibhuti Bhusan; Khuntia, Hemanta Kumar; Achary, K Gopinath; Khuntia, Chinmaye Priyadarshini

    2015-04-01

    The epidemics of cholera were reported in the Kashipur, K.singhpur, B cuttack blocks of Rayagada district and Mohana block of Gajapati district of Odisha during 2010. The present study was carried out to isolate the bacterial pathogen, its drug sensitivity pattern and to describe the spread of the disease in those areas. A total of 68 rectal swabs collected from patients with severe diarrhea, admitted to different health centers and diarrhea affected villages were bacteriologically analyzed. Similarly 22 water samples collected from different villages from nala, chua, etc were tested for the presence of V cholerae. Out of 68 rectal swabs tested 35 (51.5%) were V cholerae O1 Ogawa and 14(20.6%) were E coli; which might be commensals. All water samples were negative for V cholerae. The V cholerae strains were sensitive to gentamicin, norfloxacin, ciprofloxacin, azithromycin and ofloxacin; but were resistant to ampicillin, tetracycline, nalidixic acid, furazolidone, streptomycin, erythromycin, co-trimoxazole, neomycin and chloramphenicol. All V cholerae strains were 100% resistant to tetracycline and they were El Tor variants harboring ctxB gene of classical strain. The present study indicated the emergence and spread of tetracycline resistant V cholerae O1 El Tor variant in the tribal areas which needs close monitoring. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Inhibition of nalidixic acid-resistant salmonella on marinated chicken skin.

    PubMed

    Pathania, A; McKee, S R; Bilgili, S F; Singh, M

    2010-11-01

    Marination is widely used to enhance flavor and increase consumer acceptability of meat and poultry products. The impact of such marination on the safety and shelf life of poultry meat was evaluated in this study. A series of experiments were conducted to determine the efficacy of teriyaki and lemon pepper marinades against multiple strains of nalidixic acid (NAL)-resistant Salmonella. NAL-resistant Salmonella serovar (Typhimurium, Heidelberg, and Senftenberg) cultures were inoculated onto chicken skin at 0.6 to 3.14 log CFU/g in a 12-well titer plate. Inoculated chicken skin was exposed to teriyaki or lemon pepper marinades for up to 32 h and stored at 4 or 25°C to determine the prevalence of Salmonella. To determine Salmonella survival, a three-strain cocktail of Salmonella was inoculated at low (ca. 4 log CFU/g) and high (8 log CFU/g) levels onto chicken skin that was then marinated with either teriyaki or lemon pepper marinade for up to 32 h and stored at 4 or 25°C. Prevalence of Salmonella was significantly reduced (P ≤ 0.05) by teriyaki marinade at all levels of contamination regardless of storage temperature. Lemon pepper marinade reduced Salmonella prevalence (P ≤ 0.05) at low levels of contamination (10¹ and 10² CFU/g), whereas no significant effect (P > 0.05) was observed at higher levels of contamination. Marination of chicken skin with teriyaki marinade greatly reduced Salmonella prevalence and survival (P ≤ 0.05) regardless of the storage temperature, indicating the antimicrobial potential of this marinade for poultry and meat products.

  7. Species differences in the disposition and metabolism of nalidixic acid.

    PubMed

    Nomeir, A A; Markham, P; Burka, L T; Griffin, R J; Ghanayem, B I

    1996-10-01

    Nalidixic acid (NA) is an antimicrobial drug that has been used to treat urinary tract infections. A study of NA by the National Toxicology Program indicated that chronic administration in the diet at doses equivalent to 82 and 175 mg/kg/day for rats, and 175 and 475 mg/kg/day for mice resulted in neoplastic lesions in the preputial and clitoral glands of male and female Fischer 344 rats, respectively, but not in male and female B6C3F1 mice. Our study was designed to evaluate the metabolic basis of this species and tissue-dependent carcinogenicity. [14C]NA was administered by oral gavage as a suspension in corn oil at doses of 20, 200 or 500 mg/kg. Based on urinary excretion data, at least 35 to 46 and 57 to 79% of dose was absorbed from the gastrointestinal tracts of mice and rats, respectively. NA-derived radioactivity was excreted primarily in urine and feces. The urinary and fecal metabolite profiles were species dependent. At 72 hr after administration, in both genders of rats and mice, the highest concentrations of radioactivity were observed in the liver, and the lowest were in the brain and adipose tissue. The preputial and clitoral glands of male and female rats, respectively, contained consistently and substantially higher concentrations of radioactivity compared to all other tissues, with the exception of liver. In mice, the levels of radioactivity in these tissues were near or below quantifiable levels. The metabolism and disposition characteristics of NA were linear in male and female mice over a dose range of 20 to 500 mg/kg: in rats, they were dose dependent. Results of this study suggest that the species- and tissue-dependent differences in carcinogenicity of NA were associated with differences in metabolism and disposition between the two species.

  8. Antimicrobial-resistant fecal bacteria from ceftiofur-treated and nonantimicrobial-treated comingled beef cows at a cow-calf operation

    USDA-ARS?s Scientific Manuscript database

    We compared the occurrences of 3rd-generation cephalosporin-resistant (3GCr ), tetracycline-resistant (TETr) and trimethoprim-sulfamethoxazole-resistant (COTr ) Escherichia coli, 3GCr Salmonella enterica, nalidixic acid-resistant (NALr) S. enterica and erythromycin-resistant (ERYr) enterococci from ...

  9. Antimicrobial resistance in Escherichia coli and Salmonella spp. isolates from fresh produce and the impact to food safety.

    PubMed

    Vital, Pierangeli G; Caballes, Marie Bernadine D; Rivera, Windell L

    2017-09-02

    Foodborne diseases associated with fresh produce consumption have escalated worldwide, causing microbial safety of produce of critical importance. Bacteria that have increasingly been detected in fresh produce are Escherichia coli and Salmonella spp., both of which have been shown to progressively display antimicrobial resistance. The study focused on the assessment of antimicrobial resistance of these enteric bacteria from different kinds of fresh produce from various open air markets and supermarkets in the Philippines. Using the disk diffusion assay on a total of 50 bacterial isolates obtained from 410 fresh produce surveyed, monoresistance to tetracycline was observed to be the most prevalent (38%), followed by multidrug resistance to tetracycline, chloramphenicol, ciprofloxacin, and nalidixic acid (4%), and lastly by dual resistance to tetracycline and chloramphenicol (2%). Using multiplex and simplex polymerase chain reaction (PCR) assays, tetA (75%) and tetB (9%) were found in tetracycline resistant isolates, whereas catI (67%) and catIII (33%) were detected in chloramphenicol resistant isolates. Sequence analysis of gyr and par genes from the ciprofloxacin and nalidixic acid resistant isolates revealed different mutations. Based on the results, fresh produce act as a reservoir of these antibiotic resistant bacteria which may pose health threat to consumers.

  10. Gallic acid-based indanone derivative interacts synergistically with tetracycline by inhibiting efflux pump in multidrug resistant E. coli.

    PubMed

    Dwivedi, Gaurav Raj; Tiwari, Nimisha; Singh, Aastha; Kumar, Akhil; Roy, Sudeep; Negi, Arvind Singh; Pal, Anirban; Chanda, Debabrata; Sharma, Ashok; Darokar, Mahendra P

    2016-03-01

    The purpose of the present study was to study the synergy potential of gallic acid-based derivatives in combination with conventional antibiotics using multidrug resistant cultures of Escherichia coli. Gallic acid-based derivatives significantly reduced the MIC of tetracycline against multidrug resistant clinical isolate of E. coli. The best representative, 3-(3',4,'5'-trimethoxyphenyl)-4,5,6-trimethoxyindanone-1, an indanone derivative of gallic acid, was observed to inhibit ethidium bromide efflux and ATPase which was also supported by in silico docking. This derivative extended the post-antibiotic effect and decreased the mutation prevention concentration of tetracycline. This derivative in combination with TET was able to reduce the concentration of TNFα up to 18-fold in Swiss albino mice. This derivative was nontoxic and well tolerated up to 300 mg/kg dose in subacute oral toxicity study in mice. This is the first report of gallic acid-based indanone derivative as drug resistance reversal agent acting through ATP-dependent efflux pump inhibition.

  11. Reaction of tetracycline with biologically relevant chloramines

    NASA Astrophysics Data System (ADS)

    Benavides, J.; Barrias, P.; Piro, N.; Arenas, A.; Orrego, A.; Pino, E.; Villegas, L.; Dorta, E.; Aspée, A.; López-Alarcón, C.

    2017-05-01

    Helicobacter pylori (H. pylori) infection triggers inflammatory processes with the consequent production of hypochlorous acid (HOCl), monochloramine (NH2Cl), and protein-derived chloramines. As the therapy for eradicating H. pylori is partially based on the use of tetracycline, we studied the kinetic of its consumption elicited by HOCl, NH2Cl, N-chloro-n-butylamine (NHCl-But, used as a lysine-derived chloramine model), and lysozyme-derived chloramines. In the micromolar concentration range, tetracycline reacted rapidly with HOCl, generating in the first few seconds intermediates of short half-life. In contrast, a slow tetracycline consumption was observed in the presence of high NH2Cl and NHCl-But concentrations (millimolar range). Similar chlorinated products of tetracycline were identified by mass spectrometry, in the presence of HOCl and NH2Cl. These results evidenced that tautomers of tetracycline are pivotal intermediates in all reactions. In spite of the low reactivity of chloramines towards tetracycline, it is evident that, in the concentration range where they are produced in a H. pylori infection (millimolar range), the reactions lead to oxidation and/or chlorination of tetracycline. This kind of reactions, which were also observed triggered by lysozyme-derived chloramines, could limit the efficiency of the tetracycline-based therapy.

  12. Release of tetracycline hydrochloride from electrospun poly(ethylene-co-vinylacetate), poly(lactic acid), and a blend.

    PubMed

    Kenawy, El-Refaie; Bowlin, Gary L; Mansfield, Kevin; Layman, John; Simpson, David G; Sanders, Elliot H; Wnek, Gary E

    2002-05-17

    Electrospun fiber mats are explored as drug delivery vehicles using tetracycline hydrochloride as a model drug. The mats were made either from poly(lactic acid) (PLA), poly(ethylene-co-vinyl acetate) (PEVA), or from a 50:50 blend of the two. The fibers were electrospun from chloroform solutions containing a small amount of methanol to solubilize the drug. The release of the tetracycline hydrochloride from these new drug delivery systems was followed by UV-VIS spectroscopy. Release profiles from the electrospun mats were compared to a commercially available drug delivery system, Actisite (Alza Corporation, Palo Alto, CA), as well as to cast films of the various formulations.

  13. [Analysis on the antimicrobial resistance of lactic acid bacteria isolated from the yogurt sold in China].

    PubMed

    Fan, Qin; Liu, Shuliang; Li, Juan; Huang, Tingting

    2012-05-01

    To analyze the antimicrobial susceptibility of lactic acid bacteria (LAB) from yogurt, and to provide references for evaluating the safety of LAB and screening safe strains. The sensitivity of 43 LAB strains, including 14 strains of Streptococcus thermophilus, 12 strains of Lactobacillus acidophilus, 9 strains of Lactobacillus bulgaricus and 8 strains of Bifidobacterium, to 22 antibiotics were tested by agar plate dilution method. All 43 LAB strains were resistant to trimethoprim, nalidixic acid, ciprofloxacin, lomefloxacin, danofloxacin and polymyxin E. Their resistances to kanamycin, tetracycline, clindamycin, doxycycline and cephalothin were varied. The sensitivity to other antibiotics were sensitive or moderate. All isolates were multidrug-resistant. The antimicrobial resistance of tested LAB strains was comparatively serious, and continuously monitoring their antimicrobial resistance and evaluating their safety should be strengthened.

  14. Evaluation of degradation of antibiotic tetracycline in pig manure by electron beam irradiation.

    PubMed

    Cho, Jae-Young

    2010-04-01

    This study was carried out to evaluate the degradation efficiency and intermediate products of the tetracycline from artificially contaminated pig manure using of electron beam irradiation as a function of the absorbed dose. The degradation efficiency of tetracycline was 42.77% at 1 kGy, 64.20% at 3 kGy, 77.83% at 5 kGy, and 90.50% at 10 kGy. The initial concentration of tetracycline (300 mg kg(-1)) in pig manure decreased significantly to 24.2 +/- 5.3 mg kg(-1) after electron beam irradiation at 10 kGy. The radiolytic degradation products of tetracycline were 1,4-benzenedicarboxylic acid, hexadecanoic acid, 9-octadecenamide, 11-octadecenamide, and octadecanoic acid.

  15. Electrochemical reduction of nalidixic acid at glassy carbon electrode modified with multi-walled carbon nanotubes.

    PubMed

    Patiño, Yolanda; Pilehvar, Sanaz; Díaz, Eva; Ordóñez, Salvador; De Wael, Karolien

    2017-02-05

    The aqueous phase electrochemical degradation of nalidixic acid (NAL) is studied in this work, using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as instrumental techniques. The promotional effect of multi-walled carbon nanotubes (MWCNT) on the performance of glassy carbon electrodes is demonstrated, being observed that these materials catalyze the NAL reduction. The effect of surface functional groups on MWCNT -MWCNT-COOH and MWCNT-NH 2 -was also studied. The modification of glassy carbon electrode (GCE) with MWCNT leads to an improved performance for NAL reduction following the order of MWCNT>MWCNT-NH 2 >MWCNT-COOH. The best behavior at MWCNT-GCE is mainly due to both the increased electrode active area and the enhanced MWCNT adsorption properties. The NAL degradation was carried out under optimal conditions (pH=5.0, deposition time=20s and volume of MWCNT=10μL) using MWCNT-GCE obtaining an irreversible reduction of NAL to less toxic products. Paramaters as the number of DPV cycles and the volume/area (V/A) ratio were optimized for maximize pollutant degradation. It was observed that after 15 DPV scans and V/A=8, a complete reduction was obtained, obtaining two sub-products identified by liquid chromatography-mass spectrometry (LC-MS). Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Synthesis, Characterization, and Biological Activity Studies of Copper(II) Mixed Compound with Histamine and Nalidixic Acid

    PubMed Central

    Bivián-Castro, Egla Yareth; López, Mercedes G.; Pedraza-Reyes, Mario; Bernès, Sylvain; Mendoza-Díaz, Guillermo

    2009-01-01

    A mixed copper complex with deprotonated nalidixic acid (nal) and histamine (hsm) was synthesized and characterized by FTIR, UV-Vis, elemental analysis, and conductivity. The crystal structure of [Cu(hsm)(nal)H2O]Cl·3H2O (chn) showed a pentacoordinated cooper(II) in a square pyramidal geometry surrounded by two N atoms from hsm, two O atoms from the quinolone, and one apical water oxygen. Alteration of bacterial DNA structure and/or associated functions in vivo by [Cu(hsm)(nal)H2O]Cl·3H2O was demonstrated by the induction of a recA-lacZ fusion integrated at the amyE locus of a recombinant Bacillus subtilis strain. Results from circular dichroism and denaturation of calf thymus DNA (CT-DNA) suggested that increased amounts of copper complex were able to stabilize the double helix of DNA in vitro mainly by formation of hydrogen bonds between chn and the sugars of DNA minor groove. In vivo and in vitro biological activities of the chn complex were compared with the chemical nuclease [Cu(phen)(nal)H2O]NO3 · 3H2O (cpn) where phen is phenanthroline. PMID:19557138

  17. Oxidative degradation of nalidixic acid by nano-magnetite via Fe2+/O2-mediated reactions.

    PubMed

    Ardo, Sandy G; Nélieu, Sylvie; Ona-Nguema, Georges; Delarue, Ghislaine; Brest, Jessica; Pironin, Elsa; Morin, Guillaume

    2015-04-07

    Organic pollution has become a critical issue worldwide due to the increasing input and persistence of organic compounds in the environment. Iron minerals are potentially able to degrade efficiently organic pollutants sorbed to their surfaces via oxidative or reductive transformation processes. Here, we explored the oxidative capacity of nano-magnetite (Fe3O4) having ∼ 12 nm particle size, to promote heterogeneous Fenton-like reactions for the removal of nalidixic acid (NAL), a recalcitrant quinolone antibacterial agent. Results show that NAL was adsorbed at the surface of magnetite and was efficiently degraded under oxic conditions. Nearly 60% of this organic contaminant was eliminated after 30 min exposure to air bubbling in solution in the presence of an excess of nano-magnetite. X-ray diffraction (XRD) and Fe K-edge X-ray absorption spectroscopy (XANES and EXAFS) showed a partial oxidation of magnetite to maghemite during the reaction, and four byproducts of NAL were identified by liquid chromatography-mass spectroscopy (UHPLC-MS/MS). We also provide evidence that hydroxyl radicals (HO(•)) were involved in the oxidative degradation of NAL, as indicated by the quenching of the degradation reaction in the presence of ethanol. This study points out the promising potentialities of mixed valence iron oxides for the treatment of soils and wastewater contaminated by organic pollutants.

  18. Synthesis of Ethyl Nalidixate: A Medicinal Chemistry Experiment

    ERIC Educational Resources Information Center

    Leslie, Ray; Leeb, Elaine; Smith, Robert B.

    2012-01-01

    A series of laboratory experiments that complement a medicinal chemistry lecture course in drug design and development have been developed. The synthesis of ethyl nalidixate covers three separate experimental procedures, all of which can be completed in three, standard three-hour lab classes and incorporate aspects of green chemistry such as…

  19. Prevalence, antimicrobial resistance and genetic diversity of Campylobacter coli and Campylobacter jejuni in Ecuadorian broilers at slaughter age

    PubMed Central

    Vinueza-Burgos, Christian; Wautier, Magali; Martiny, Delphine; Cisneros, Marco; Van Damme, Inge; De Zutter, Lieven

    2017-01-01

    Abstract Thermotolerant Campylobacter spp. are a major cause of foodborne gastrointestinal infections worldwide. The linkage of human campylobacteriosis and poultry has been widely described. In this study we aimed to investigate the prevalence, antimicrobial resistance and genetic diversity of C. coli and C. jejuni in broilers from Ecuador. Caecal content from 379 randomly selected broiler batches originating from 115 farms were collected from 6 slaughterhouses located in the province of Pichincha during 1 year. Microbiological isolation was performed by direct plating on mCCDA agar. Identification of Campylobacter species was done by PCR. Minimum inhibitory concentration (MIC) values for gentamicin, ciprofloxacin, nalidixic acid, tetracycline, streptomycin, and erythromycin were obtained. Genetic variation was assessed by RFLP-flaA typing and Multilocus Sequence Typing (MLST) of selected isolates. Prevalence at batch level was 64.1%. Of the positive batches 68.7% were positive for C. coli, 18.9% for C. jejuni, and 12.4% for C. coli and C. jejuni. Resistance rates above 67% were shown for tetracycline, ciprofloxacin, and nalidixic acid. The resistance pattern tetracycline, ciprofloxin, and nalidixic acid was the dominant one in both Campylobacter species. RFLP-flaA typing analysis showed that C. coli and C. jejuni strains belonged to 38 and 26 profiles respectively. On the other hand MLST typing revealed that C. coli except one strain belonged to CC-828, while C. jejuni except 2 strains belonged to 12 assigned clonal complexes (CCs). Furthermore 4 new sequence types (STs) for both species were described, whereby 2 new STs for C. coli were based on new allele sequences. Further research is necessary to estimate the impact of the slaughter of Campylobacter positive broiler batches on the contamination level of carcasses in slaughterhouses and at retail in Ecuador. PMID:28339716

  20. Microplastics play a minor role in tetracycline sorption in the presence of dissolved organic matter.

    PubMed

    Xu, Baile; Liu, Fei; Brookes, Philip C; Xu, Jianming

    2018-09-01

    Microplastics have a great potential to sorb organic pollutants from the adjacent environment. In this study, the sorption of tetracycline, a polar and ionizable antibiotic, on three types of microplastics (polyethylene (PE), polypropylene (PP) and polystyrene (PS)) were investigated in batch sorption experiments. The sorption isotherms were well fitted by the Langmuir model, indicating that not only hydrophobic interactions but also other interactions (e.g. electrostatic interactions) played important roles in the sorption process. PS had the maximum sorption capacity, following the order PS > PP > PE, which can be attributed to polar interactions and π-π interactions. The sorption of tetracycline on microplastics was significantly influenced by pH, with sorption capacity increasing gradually, peaking at pH 6.0 and then decreasing, likely due to the influence of tetracycline speciation with the change of pH. Fulvic acid was selected as representative dissolved organic matter (DOM) to examine the effect on sorption. The increasing concentration of fulvic acid inhibited the sorption of tetracycline on three microplastics, decreasing them by more than 90% at the fulvic acid concentration of 20 mg/L, which implied a greater affinity of tetracycline to fulvic acid than to microplastics. Increasing salinity from 0.05 to 3.5% had negligible effects on the sorption of tetracycline on the three microplastics. Our results highlight the importance of pH and DOM on the sorption of tetracycline on microplastics, and suggest the relatively minor role of microplastics in the fate and transport of tetracycline in the aquatic environment in the presence of DOM. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Influence of tetracycline on tetracycline-resistant heterotrophs and tet genes in activated sludge process.

    PubMed

    Yu, Jie; Liu, Dongfang; Li, Kexun

    2015-03-01

    The concentrations of tetracycline-intermediate resistant, tetracycline-resistant heterotrophic bacteria, and total heterotrophic bacteria were examined to assess the influence of tetracycline on tetracycline-resistant heterotrophs by the R2A agar cultivation method in the tetracycline fortified activated sludge process and in the natural background. Results showed that the percentages of both tetracycline-intermediate resistant and tetracycline-resistant heterotrophic bacteria in total heterotrophic bacteria were significantly increased, after tetracycline was fed to activated sludge for a 3 months period under four different operating conditions, as compared with the background. In order to investigate the mechanism of activated sludge resistance to tetracycline, polymerase chain reaction experiments were carried out to analyze the existence and evolution of tet genes in the presence of tetracycline. Results revealed that only tet A and tet B genes out of the 11 target tet genes were observed in tetracycline treated activated sludge while no tet gene was detected in background. This indicated that tet A gene could accumulate in activated sludge with slower and continuous influent, while the accumulation of tet B gene could be attributed to shorter hydraulic retention time. Therefore, it was proposed in this study that tetracycline-resistant genes created by efflux pumps spread earlier and quicker to encode resistance to tetracycline, which facilitated the increase in tetracycline-resistance.

  2. Effective Removal of Tetracycline from Aqueous Solution by Organic Acid-Coated Magnetic Nanoparticles.

    PubMed

    Guo, Liang; Liang, Yuyan; Chen, Xuelan; Xu, Wei; Wu, Kesheng; Wei, Hua; Xiong, Yonghua

    2016-03-01

    Self-assembled iron oxide nanocomposites are good magnetic nano-adsorbents that can be prepared using simple methods. Four types of organic acid-functionalised (oleic acid, undecenoic acid, caprylic acid or hexanoic acid) magnetic nanoparticles (MNPs) were synthesised through a one-pot chemisorption method for the removal of tetracycline (TC) from aqueous solution. The undecenoic acid-coated MNPs (UA-MNPs) exhibited the highest adsorption efficiency and can be easily retrieved with a low-gradient magnetic separator (0.4 Tesla) at pH 5.0 aqueous solution. The TC adsorption process on the UA-MNPs followed the Langmuir isotherm and the maximum adsorption capacities increased from 86.96 mg g(-1) to 222.2 mg g(-1) with the increase in temperature from 288 K to 318 K. The kinetics of adsorption fits pseudo-second-order model perfectly with a rate constant, 5.946 g mg(-1) min(-1) at 298 K. The positive values of the enthalpy (AH) and the negative value of the free energy (AG) indicated an endothermic and spontaneous adsorption process of TC on the UA-MNPs. Moreover, the UA-MNPs possessed excellent ability to adsorb the other three major types of TC antibiotics, including chlortetracycline, oxytetracycline and doxycycline.

  3. Propionibacterium acnes is developing gradual increase in resistance to oral tetracyclines.

    PubMed

    Nakase, Keisuke; Nakaminami, Hidemasa; Takenaka, Yuko; Hayashi, Nobukazu; Kawashima, Makoto; Noguchi, Norihisa

    2017-01-01

    Propionibacterium acnes is an anaerobic bacterium that causes deep infection in organs and prosthetic joints, in addition to acne vulgaris. Many tetracycline-resistant P. acnes strains have been isolated because oral tetracyclines are frequently used as an acne treatment against P. acnes. In this study, we found a novel tetracycline resistance mechanism in P. acnes. Three doxycycline-resistant (MIC: 16 µg ml-1) strains were isolated from 69 strains in acne patients in Japan between 2010 and 2011. Additionally, six insusceptible strains (MIC: 1-2 µg ml-1) that had reduced susceptibility compared to susceptible strains (MIC: ≤0.5 µg ml-1) were identified. All doxycycline-resistant strains had a G1036C mutation in the 16S rRNA gene in addition to an amino acid substitution in the ribosomal S10 protein encoded by rpsJ. By contrast, insusceptible strains had an amino acid substitution in the S10 protein but no mutation in the 16S rRNA. When the mutant with decreased susceptibility to doxycycline was obtained in vitro, only the mutated S10 protein was found (MIC: 4 µg ml-1), not the mutated 16S rRNA gene. This result shows that the S10 protein amino acid substitution contributes to reduced doxycycline susceptibility in P. acnes and suggests that tetracycline resistance is acquired through a 16S rRNA mutation after the S10 protein amino acid substitution causes reduced susceptibility.

  4. [Considerations on the antibiotic activity (M.I.C.) revealed in 247 serotypes of Salmonella].

    PubMed

    Pitzus, E; Peretti, P; Ghinelli, P; Bisicchia, R; Turano, A

    1975-01-01

    247 strains of Salmonella, isolated in Brescia province duriing 1973-1974 have been typed by serological methods. The MIC has been determined, using the following antibiotics: chloramphenicol, tetracycline HCL, ampicillin, doxycycline, rifampicin, cephazolin, carbenicillin, nifuratel, gentamicin, aminosidine, trimetho-prim-sulphamethoazole, nalidixic acid. The pattern of resistence of the various serotypes is quite constant. The relationship between diffusion and epidermiological factors are discussed.

  5. Escherichia coli mutants thermosensitive for deoxyribonucleic acid gyrase subunit A: effects on deoxyribonucleic acid replication, transcription, and bacteriophage growth.

    PubMed

    Kreuzer, K N; Cozzarelli, N R

    1979-11-01

    Temperature-sensitive nalA mutants of Escherichia coli have been used to investigate the structure and functions of deoxyribonucleic acid (DNA) gyrase. Extracts of one such mutant (nalA43) had thermosensitive DNA gyrase subunit A activity but normal gyrase subunit B activity, proving definitively that nalA is the structural gene for subunit A. Extracts of a second nalA (Ts) mutant (nalA45) had a 50-fold deficiency of gyrase subunit A activity. The residual DNA supertwisting was catalyzed by the mutant DNA gyrase rather than by a novel supertwisting enzyme. The nalA45(Ts) extract was also deficient in the nalidixic acid target, which is defined as the protein necessary to confer drug sensitivity to in vitro DNA replication directed by a nalidixic acid-resistant mutant extract. Thus, gyrase subunit A and the nalidixic acid target are one and the same protein, the nalA gene product. Shift of the nalA43(Ts) mutant to a nonpermissive temperature resulted in a precipitous decline in the rate of [(3)H]thymidine incorporation, demonstrating an obligatory role of the nalA gene product in DNA replication. The rates of incorporation of [(3)H]uridine pulses and continuously administered [(3)H]uracil were quickly reduced approximately twofold upon temperature shift of the nalA43(Ts) mutant, and therefore some but not all transcription requires the nalA gene product. The thermosensitive growth of bacteriophages phiX174 and T4 in the nalA43(Ts) host shows that these phages depend on the host nalA gene product. In contrast, the growth of phage T7 was strongly inhibited by nalidixic acid but essentially unaffected by the nalA43(Ts) mutation. The inhibition of T7 growth by nalidixic acid was, however, eliminated by temperature inactivation of the nal43 gene product. Therefore, nalidixic acid may block T7 growth by a corruption rather than a simple elimination of the nalidixic acid target. Possible mechanisms for such a corruption are considered, and their relevance to the puzzling

  6. Controlled-release of tetracycline and lovastatin by poly(d,l-lactide-co-glycolide acid)-chitosan nanoparticles enhances periodontal regeneration in dogs

    PubMed Central

    Lee, Bor-Shiunn; Lee, Chien-Chen; Wang, Yi-Ping; Chen, Hsiao-Jan; Lai, Chern-Hsiung; Hsieh, Wan-Ling; Chen, Yi-Wen

    2016-01-01

    Chronic periodontitis is characterized by inflammation of periodontal tissues, leading to bone resorption and tooth loss. The goal of treatment is to regenerate periodontal tissues including bone and cementum lost as a consequence of disease. The local delivery of tetracycline was proven to be effective in controlling localized periodontal infection without apparent side effects. Previous studies suggested that lovastatin has a significant role in new bone formation; however, the local delivery of lovastatin might enhance its therapeutic effects. A number of local delivery devices have been developed recently, including poly(d,l-lactide-co-glycolide acid) (PLGA) nanoparticles. The aim of this study was to develop a local delivery device, PLGA-lovastatin-chitosan-tetracycline nanoparticles, which allows the sequential release of tetracycline and lovastatin to effectively control local infection and promote bone regeneration in periodontitis. The size and microstructure of nanoparticles were examined by transmission electron microscopy, Nanoparticle Size Analyzer, and Fourier transform infrared spectroscopy. The release of tetracycline and lovastatin was quantified using a UV-Vis spectrophotometer. Furthermore, the cytotoxic effect and alkaline phosphatase activity of the nanoparticles in osteoblast cell cultures as well as antibacterial activity against periodontal pathogens were investigated. Finally, the bone regeneration potential of PLGA nanoparticles in three-walled defects in beagle dogs was investigated. The results indicated that PLGA-lovastatin-chitosan-tetracycline nanoparticles showed good biocompatibility, antibacterial activity, and increased alkaline phosphatase activity. The volumetric analysis from micro-CT revealed significantly increased new bone formation in defects filled with nanoparticles in dogs. This novel local delivery device might be useful as an adjunctive treatment in periodontal regenerative therapy. PMID:26848264

  7. Controlled-release of tetracycline and lovastatin by poly(D,L-lactide-co-glycolide acid)-chitosan nanoparticles enhances periodontal regeneration in dogs.

    PubMed

    Lee, Bor-Shiunn; Lee, Chien-Chen; Wang, Yi-Ping; Chen, Hsiao-Jan; Lai, Chern-Hsiung; Hsieh, Wan-Ling; Chen, Yi-Wen

    2016-01-01

    Chronic periodontitis is characterized by inflammation of periodontal tissues, leading to bone resorption and tooth loss. The goal of treatment is to regenerate periodontal tissues including bone and cementum lost as a consequence of disease. The local delivery of tetracycline was proven to be effective in controlling localized periodontal infection without apparent side effects. Previous studies suggested that lovastatin has a significant role in new bone formation; however, the local delivery of lovastatin might enhance its therapeutic effects. A number of local delivery devices have been developed recently, including poly(D,L-lactide-co-glycolide acid) (PLGA) nanoparticles. The aim of this study was to develop a local delivery device, PLGA-lovastatin-chitosan-tetracycline nanoparticles, which allows the sequential release of tetracycline and lovastatin to effectively control local infection and promote bone regeneration in periodontitis. The size and microstructure of nanoparticles were examined by transmission electron microscopy, Nanoparticle Size Analyzer, and Fourier transform infrared spectroscopy. The release of tetracycline and lovastatin was quantified using a UV-Vis spectrophotometer. Furthermore, the cytotoxic effect and alkaline phosphatase activity of the nanoparticles in osteoblast cell cultures as well as antibacterial activity against periodontal pathogens were investigated. Finally, the bone regeneration potential of PLGA nanoparticles in three-walled defects in beagle dogs was investigated. The results indicated that PLGA-lovastatin-chitosan-tetracycline nanoparticles showed good biocompatibility, antibacterial activity, and increased alkaline phosphatase activity. The volumetric analysis from micro-CT revealed significantly increased new bone formation in defects filled with nanoparticles in dogs. This novel local delivery device might be useful as an adjunctive treatment in periodontal regenerative therapy.

  8. Sorption of tetracycline antibiotics on hyper-crosslinked polystyrene from aqueous and aqueous-organic media

    NASA Astrophysics Data System (ADS)

    Udalova, A. Yu.; Dmitrienko, S. G.; Apyari, V. V.

    2015-06-01

    The sorption of tetracycline, oxytetracycline, chlortetracycline, and doxycycline on hyper-cross-linked polystyrene from aqueous and aqueous-organic solutions is studied under static and dynamic conditions in order to extend the range of the sorbents suitable for sorption isolation and the preconcentration of tetracycline antibiotics. Features of tetracycline sorption depending on the acidity of a solution and the nature and concentration of the compounds are explained. It is shown that hyper-crosslinked polystyrene can be used for the group sorption preconcentration of these compounds.

  9. Biochemical analysis of the biosynthetic pathway of an anticancer tetracycline SF2575.

    PubMed

    Pickens, Lauren B; Kim, Woncheol; Wang, Peng; Zhou, Hui; Watanabe, Kenji; Gomi, Shuichi; Tang, Yi

    2009-12-09

    SF2575 1 is a tetracycline polyketide produced by Streptomyces sp. SF2575 and displays exceptionally potent anticancer activity toward a broad range of cancer cell lines. The structure of SF2575 is characterized by a highly substituted tetracycline aglycon. The modifications include methylation of the C-6 and C-12a hydroxyl groups, acylation of the 4-(S)-hydroxyl with salicylic acid, C-glycosylation of the C-9 of the D-ring with D-olivose and further acylation of the C4'-hydroxyl of D-olivose with the unusual angelic acid. Understanding the biosynthesis of SF2575 can therefore expand the repertoire of enzymes that can modify tetracyclines, and facilitate engineered biosynthesis of SF2575 analogues. In this study, we identified, sequenced, and functionally analyzed the ssf biosynthetic gene cluster which contains 40 putative open reading frames. Genes encoding enzymes that can assemble the tetracycline aglycon, as well as installing these unique structural features, are found in the gene cluster. Biosynthetic intermediates were isolated from the SF2575 culture extract to suggest the order of pendant-group addition is C-9 glycosylation, C-4 salicylation, and O-4' angelylcylation. Using in vitro assays, two enzymes that are responsible for C-4 acylation of salicylic acid were identified. These enzymes include an ATP-dependent salicylyl-CoA ligase SsfL1 and a putative GDSL family acyltransferase SsfX3, both of which were shown to have relaxed substrate specificity toward substituted benzoic acids. Since the salicylic acid moiety is critically important for the anticancer properties of SF2575, verification of the activities of SsfL1 and SsfX3 sets the stage for biosynthetic modification of the C-4 group toward structure-activity relationship studies of SF2575. Using heterologous biosynthesis in Streptomyces lividans, we also determined that biosynthesis of the SF2575 tetracycline aglycon 8 parallels that of oxytetracycline 4 and diverges after the assembly of 4-keto

  10. Bismuth, Metronidazole, and Tetracycline

    MedlinePlus

    Helidac® (as a kit containing Bismuth Subsalicylate, Metronidazole, Tetracycline) ... Bismuth, metronidazole, and tetracycline is used along with other ulcer medications to treat duodenal ulcers. It is in a ...

  11. Molecular typing, antibiotic resistance, virulence gene and biofilm formation of different Salmonella enterica serotypes.

    PubMed

    Turki, Yousra; Mehr, Ines; Ouzari, Hadda; Khessairi, Amel; Hassen, Abdennaceur

    2014-01-01

    Salmonella enterica isolates representing commonly isolated serotypes in Tunisia were analyzed using genotyping and phenotyping methods. ERIC and ITS-PCR applied to 48 Salmonella spp. isolates revealed the presence of 12 and 10 different profiles, respectively. The distribution of profiles among serotypes demonstrated the presence of strains showing an identical fingerprinting pattern. All Salmonella strains used in this study were positive for the sdiA gene. Three Salmonella isolates belonging to serotypes Anatum, Enteritidis and Amsterdam were negative for the invA gene. The spvC gene was detected in thirteen isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Gallinarum and Montevideo. Antibiotic resistance was frequent among the recovered Salmonella isolates belonging to serotypes Anatum, Typhimurium, Enteritidis, Zanzibar and Derby. The majority of these isolates exhibited resistance to at least two antibiotic families. Four multidrug-resistant isolates were recovered from food animals and poultry products. These isolates exhibited not only resistance to tetracycline, sulphonamides, and ampicillin, but also have shown resistance to fluoroquinolones. Common resistance to nalidixic acid, ciprofloxacin and ofloxacin in two S. Anatum and S. Zanzibar strains isolated from raw meat and poultry was also obtained. Furthermore, wastewater and human isolates exhibited frequent resistance to nalidixic acid and tetracycline. Of all isolates, 33.5% were able to form biofilm.

  12. Effect of tannic and gallic acids alone or in combination with carbenicillin or tetracycline on Chromobacterium violaceum CV026 growth, motility, and biofilm formation.

    PubMed

    Dusane, Devendra H; O'May, Che; Tufenkji, Nathalie

    2015-07-01

    Chromobacterium violaceum is an opportunistic pathogen that causes infections that are difficult to treat. The goal of this research was to evaluate the effect of selected tannins (tannic acid (TA) and gallic acid (GA)) on bacterial growth, motility, antibiotic (carbenicillin, tetracycline) susceptibility, and biofilm formation. Both tannins, particularly TA, impaired bacterial growth levels and swimming motilities at sub-minimum inhibitory concentrations (sub-MICs). In combination with tannins, antibiotics showed increased MICs, suggesting that tannins interfered with antibacterial activity. Sub-MICs of tetracycline or TA alone enhanced biofilm formation of C. violaceum; however, in combination, these compounds inhibited biofilm formation. In contrast, carbenicillin at sub-MICs was effective in inhibiting C. violaceum biofilm formation; however, in combination with lower concentrations of TA or GA, biofilms were enhanced. These results provide insights into the effects of tannins on C. violaceum growth and their varying interaction with antibiotics used to target C. violaceum infections.

  13. Antimicrobial Resistance in Nontyphoidal Salmonella Isolated from Human and Poultry-Related Samples in Brazil: 20-Year Meta-Analysis.

    PubMed

    Voss-Rech, Daiane; Potter, Luciana; Vaz, Clarissa Silveira Luiz; Pereira, Daniela Isabel Brayer; Sangioni, Luís Antonio; Vargas, Águeda Castagna; de Avila Botton, Sônia

    2017-02-01

    Nontyphoidal Salmonella are one of the leading causes of foodborne diseases in the world. As poultry products are recognized as main sources of human salmonellosis, nontyphoidal Salmonella control has become a global issue for the poultry industry. The increasing antimicrobial resistance in poultry-related nontyphoidal Salmonella serovars is a global matter of concern. By monitoring the evolution of antimicrobial resistance, alternative treatments can be identified and possible restrictions in the treatment of systemic human salmonellosis foreseen. A meta-analysis was conducted to assess the profile and temporal evolution of the antimicrobial resistance of nontyphoidal Salmonella of poultry and human origin in Brazil, isolated in the period from 1995 to 2014. Four databases were researched; twenty-nine articles met the eligibility criteria and were included in the meta-analysis. In the nontyphoidal isolates of poultry origin, the highest levels of antimicrobial resistance were verified for sulfonamides (44.3%), nalidixic acid (42.5%), and tetracycline (35.5%). In the human-origin isolates, the resistance occurred mainly for sulfonamides (46.4%), tetracycline (36.9%), and ampicillin (23.6%). Twenty-two articles described results of antimicrobial resistance specifically for Salmonella Enteritidis, also enabling the individual meta-analysis of this serovar. For most antimicrobials, the resistance levels of Salmonella Enteritidis were lower than those found when considering all the nontyphoidal serovars. In the poultry-origin isolates, a quadratic temporal distribution was observed, with reduced resistance to streptomycin in Salmonella Enteritidis and in all nontyphoidal serovars, and a linear increase of resistance to nalidixic acid in Salmonella Enteritidis. In the human-origin isolates, a linear increase was identified in the resistance to nalidixic acid in Salmonella Enteritidis and in all the nontyphoidal isolates, and to gentamicin in Salmonella Enteritidis

  14. Tetracycline

    MedlinePlus

    ... tuleramia (serious infections that may be spread on purpose as part of a bioterror attack). It can ... a serious infection that may be spread on purpose as part of a bioterror attack). Tetracycline is ...

  15. Simple and clean determination of tetracyclines by flow injection analysis

    NASA Astrophysics Data System (ADS)

    Rodríguez, Michael Pérez; Pezza, Helena Redigolo; Pezza, Leonardo

    2016-01-01

    An environmentally reliable analytical methodology was developed for direct quantification of tetracycline (TC) and oxytetracycline (OTC) using continuous flow injection analysis with spectrophotometric detection. The method is based on the diazo coupling reaction between the tetracyclines and diazotized sulfanilic acid in a basic medium, resulting in the formation of an intense orange azo compound that presents maximum absorption at 434 nm. Experimental design was used to optimize the analytical conditions. The proposed technique was validated over the concentration range of 1 to 40 μg mL- 1, and was successfully applied to samples of commercial veterinary pharmaceuticals. The detection (LOD) and quantification (LOQ) limits were 0.40 and 1.35 μg mL- 1, respectively. The samples were also analyzed by an HPLC method, and the results showed agreement with the proposed technique. The new flow injection method can be immediately used for quality control purposes in the pharmaceutical industry, facilitating monitoring in real time during the production processes of tetracycline formulations for veterinary use.

  16. Electrochemical aptasensor for detecting tetracycline in milk

    NASA Astrophysics Data System (ADS)

    Hanh Le, Thi; Phuc Pham, Van; Huyen La, Thi; Binh Phan, Thi; Huan Le, Quang

    2016-03-01

    A rapid, simple and sensitive biosensor system for tetracycline detection is very important in food safety. In this paper we developed a label-free aptasensor for electrochemical detection of tetracycline. According to the electrochemical impendence spectroscopy (EIS) analysis, there was a linear relationship between the concentration of tetracycline and the electron transfer resistance from 10 to 3000 ng ml-1 of the tetracycline concentration. The detection limit was 10 ng ml-1 in 15 min detection duration. The prepared aptasensor showed a good reproducibility with an acceptable stability in tetracycline detection. The recoveries of tetracycline in spiked milk samples were in the range of 88.1%-94.2%. The aptasensor has sensitivity 98% and specificity of 100%.

  17. SEROVARS AND ANTIMICROBIAL RESISTANCE OF Salmonella spp. ISOLATED FROM TURKEY AND BROILER CARCASSES IN SOUTHERN BRAZIL BETWEEN 2004 AND 2006

    PubMed Central

    PALMEIRA, Andre; dos SANTOS, Luciana Ruschel; BORSOI, Anderlise; RODRIGUES, Laura Beatriz; CALASANS, Max; do NASCIMENTO, Vladimir Pinheiro

    2016-01-01

    Salmonella spp. causes diseases in fowls, when species-specific serovars (Salmonella Pullorum and S.Gallinarum) are present in flocks, and public health problems, when non-typhoid serovars are isolated, as well as possible bacterial resistance induced by the preventive and therapeutic use of antimicrobials in animal production. This study describes the serovars and bacterial resistance of 280Salmonella spp. strains isolated from turkey and broiler carcasses in Southern Brazil between 2004 and 2006. SalmonellaEnteritidis was the most prevalent serovar (55.7%), followed by Heidelberg (5.0%), Agona (4.3%), Bredeney (3.9%), Hadar (3.2%), and Typhimurium (2.9%). Tennessee and S. Enterica subspecies enterica(O: 4.5) were isolated only in turkeys, and Hadar (18.6%) was the most prevalent serovar in this species. Antimicrobial susceptibility tests were performed in 178 isolates (43 from turkeys and 135 from broilers). All isolates were sensitive to amoxicillin + clavulanic acid, polymyxin B, ciprofloxacin, and norfloxacin, and were resistant to bacitracin and penicillin. Broiler carcass isolates showed resistance to nalidixic acid (48.9%), nitrofurantoin (34.3%), neomycin (9.6%), tetracycline (5.2%), and kanamycin (8.9%); and turkey carcass isolates were resistant to nalidixic acid (62.8%), tetracycline (34.9%), and neomycin (30.2%), with a significant difference in turkeys when compared to broiler carcass isolates. These results indicate the need for judicious use of antimicrobials in livestock production, given that the serovars identified are potential causes of food poisoning. PMID:27007562

  18. Flow injection chemiluminescent determination of tetracycline using a tris(2,2'-bipyridine)ruthenium(II)-cerium(IV) sulphate system.

    PubMed

    Guo, Liangqia; Xie, Zenghong; Lin, Xucong; Liu, Xiaohua; Zhang, Weilin; Chen, Guonan

    2004-01-01

    A flow-injection chemiluminescence method for the determination of tetracycline was developed. The method is based on an enhancement by tetracycline of the chemiluminescence light emission of tris(2,2'-bipyridine)ruthenium(II). In sulphuric acid medium, the chemiluminescence is generated by the continuous oxidation of tris(2,2'-bipyridine)ruthenium(II) by cerium (IV) sulphate. The light-emission intensity is greatly enhanced in the presence of tetracycline. Under the optimum conditions, the calibration curve is linear over the range 3.75 x 10(-8) g/mL-1.5 x 10(-5) g/mL for tetracycline with the linear equation: deltaINT = 205.898 x C - 20.442 (R2 = 0.9974). The detection limit is 3.27 x 10(-8) g/mL. The proposed method was also successfully used to determine tetracycline in pharmaceutical formulation (mean recovery of tetracycline, 100.7%). Copyright 2004 John Wiley & Sons, Ltd.

  19. Distribution of tetracycline resistance genes in anaerobic treatment of waste sludge: The role of pH in regulating tetracycline resistant bacteria and horizontal gene transfer.

    PubMed

    Huang, Haining; Chen, Yinguang; Zheng, Xiong; Su, Yinglong; Wan, Rui; Yang, Shouye

    2016-10-01

    Although pH value has been widely regarded as an important factor that affects resource recovery of waste sludge, the potential influence of diverse pHs on the distribution of tetracycline resistance genes (TRGs) during sludge anaerobic treatment is largely unknown. Here we reported that in the range of pH 4-10, 0.58-1.18 log unit increase of target TRGs was observed at pH 4, compared with that at pH 7, while 0.70-1.31 log unit further removal were obtained at pH 10. Mechanism study revealed that varied pHs not only altered the community structures of tetracycline resistant bacteria (TRB), but also changed their relative abundances, benefitting the propagation (acidic pHs) or attenuation (alkaline pHs) of TRB. Further investigation indicated that the amount and gene-possessing abilities of key genetic vectors for horizontal TRGs transfer were greatly promoted at acidic pHs but restricted under alkaline conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Plasticity, dynamics, and inhibition of emerging tetracycline-resistance enzymes

    PubMed Central

    Park, Jooyoung; Gasparrini, Andrew J.; Reck, Margaret R.; Symister, Chanez T.; Elliott, Jennifer L.; Vogel, Joseph P.; Wencewicz, Timothy A.; Dantas, Gautam; Tolia, Niraj H.

    2017-01-01

    While tetracyclines are an important class of antibiotics in agriculture and the clinic, their efficacy is threatened by increasing resistance. Resistance to tetracyclines can occur through efflux, ribosomal protection, or enzymatic inactivation. Surprisingly, tetracycline enzymatic inactivation has remained largely unexplored despite providing the distinct advantage of antibiotic clearance. The tetracycline destructases are a recently-discovered family of tetracycline-inactivating flavoenzymes from pathogens and soil metagenomes with a high potential for broad dissemination. Here, we show tetracycline destructases accommodate tetracycline-class antibiotics in diverse and novel orientations for catalysis, and antibiotic binding drives unprecedented structural dynamics facilitating tetracycline inactivation. We identify a key inhibitor binding mode that locks the flavin adenine dinucleotide cofactor in an inactive state, functionally rescuing tetracycline activity. Our results reveal the potential of a novel tetracycline/tetracycline destructase inhibitor combination therapy strategy to overcome resistance by enzymatic inactivation and restore the use of an important class of antibiotics. PMID:28481346

  1. Plasticity, dynamics, and inhibition of emerging tetracycline resistance enzymes.

    PubMed

    Park, Jooyoung; Gasparrini, Andrew J; Reck, Margaret R; Symister, Chanez T; Elliott, Jennifer L; Vogel, Joseph P; Wencewicz, Timothy A; Dantas, Gautam; Tolia, Niraj H

    2017-07-01

    Although tetracyclines are an important class of antibiotics for use in agriculture and the clinic, their efficacy is threatened by increasing resistance. Resistance to tetracyclines can occur through efflux, ribosomal protection, or enzymatic inactivation. Surprisingly, tetracycline enzymatic inactivation has remained largely unexplored, despite providing the distinct advantage of antibiotic clearance. The tetracycline destructases are a recently discovered family of tetracycline-inactivating flavoenzymes from pathogens and soil metagenomes that have a high potential for broad dissemination. Here, we show that tetracycline destructases accommodate tetracycline-class antibiotics in diverse and novel orientations for catalysis, and antibiotic binding drives unprecedented structural dynamics facilitating tetracycline inactivation. We identify a key inhibitor binding mode that locks the flavin adenine dinucleotide cofactor in an inactive state, functionally rescuing tetracycline activity. Our results reveal the potential of a new tetracycline and tetracycline destructase inhibitor combination therapy strategy to overcome resistance by enzymatic inactivation and restore the use of an important class of antibiotics.

  2. Antimicrobial Resistance Percentages of Salmonella and Shigella in Seafood Imported to Jordan: Higher Percentages and More Diverse Profiles in Shigella.

    PubMed

    Obaidat, Mohammad M; Bani Salman, Alaa E

    2017-03-01

    This study determined the prevalence and antimicrobial resistance of human-specific ( Shigella spp.) and zoonotic ( Salmonella enterica ) foodborne pathogens in internationally traded seafood. Sixty-four Salmonella and 61 Shigella isolates were obtained from 330 imported fresh fish samples from Egypt, Yemen, and India. The pathogens were isolated on selective media, confirmed by PCR, and tested for antimicrobial resistance. Approximately 79 and 98% of the Salmonella and Shigella isolates, respectively, exhibited resistance to at least one antimicrobial, and 8 and 49% exhibited multidrug resistance (resistance to three or more antimicrobial classes). Generally, Salmonella exhibited high resistance to amoxicillin-clavulanic acid, cephalothin, streptomycin, and ampicillin; very low resistance to kanamycin, tetracycline, gentamicin, chloramphenicol, nalidixic acid, sulfamethoxazole-trimethoprim, and ciprofloxacin; and no resistance to ceftriaxone. Meanwhile, Shigella spp. exhibited high resistance to tetracycline, amoxicillin-clavulanic acid, cephalothin, streptomycin, and ampicillin; low resistance to kanamycin, nalidixic acid, sulfamethoxazole-trimethoprim, and ceftriaxone; and very low resistance to gentamicin and ciprofloxacin. Salmonella isolates exhibited 14 resistance profiles, Shigella isolates 42. This study is novel in showing that a human-specific pathogen has higher antimicrobial resistance percentages and more diverse profiles than a zoonotic pathogen. Thus, the impact of antimicrobial use in humans is as significant as, if not more significant than, it is in animals in spreading antibiotic resistance through food. This study also demonstrates that locally derived antimicrobial resistance can spread and pose a public health risk worldwide through seafood trade and that high resistance would make a possible outbreak difficult to control. So, capacity building and monitoring harvest water areas are encouraged in fish producing countries.

  3. Photohemolytic potency of tetracyclines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bjellerup, M.; Ljunggren, B.

    1985-04-01

    Hemolysis induced by long-wave ultraviolet radiation (UVA) and 8 different commercial tetracycline derivatives was studied in a model using human red blood cells. Demethylchlortetracycline and doxycycline were shown to have pronounced hemolytic properties causing 88% and 85% hemolysis, respectively, at a concentration of 50 micrograms/ml and 72 J/ cm2 of UVA. Tetracycline, oxytetracycline, and chlortetracycline caused maximally 18% hemolysis at 200 micrograms/ml and lymecycline only 7% at 100 micrograms/ml. Methacycline showed intermediate hemolytic effect of 36% at 200 micrograms/ml. Minocycline had no hemolytic effect whatsoever. These experimental data correlate very well with clinical reports and comparative phototoxicity trials in humans.more » Photohemolysis may thus be of value for predicting tetracycline phototoxicity.« less

  4. Etiology of Tetracycline-Associated Pseudomembranous Colitis in Hamsters

    PubMed Central

    Toshniwal, Renu; Fekety, Robert; Silva, Joseph

    1979-01-01

    Tetracyclines were implicated in the 1950s in induction of protracted diarrhea and pseudomembranous colitis. Because the pathogenetic mechanism of these illnesses has been questioned recently, we studied tetracycline in hamster models of antibiotic-associated colitis. Orogastric administration of tetracycline caused diarrhea and death, with evidence of hemorrhagic typhlitis. Filtrates of cecal contents were toxic when inoculated into normal hamsters and cell culture monolayers, and toxicity was neutralized with Clostridium sordellii antitoxin. Tetracycline-resistant C. difficile was cultured from stools of these hamsters, but Staphylococcus aureus was not isolated. The value of tetracycline for treatment or prevention of clindamycin-induced colitis in hamsters was also studied, and it was found that daily orogastric administration of tetracycline was poorly protective against clindamycin-induced colitis. PMID:485127

  5. Development and validation of an HPLC method for tetracycline-related USP monographs.

    PubMed

    Hussien, Emad M

    2014-09-01

    A novel reversed-phase HPLC method was developed and validated for the assay of tetracycline hydrochloride and the limit of 4-epianhydrotetracycline hydrochloride impurity in tetracycline hydrochloride commercial bulk and pharmaceutical products. The method employed L1 (3 µm, 150 × 4.6 mm) columns, a mobile phase of 0.1% phosphoric acid and acetonitrile at a flow rate of 1.0 mL/min, and detection at 280 nm. The separation was performed in HPLC gradient mode. Forced degradation studies showed that tetracycline eluted as a spectrally pure peak and was well resolved from its degradation products. The fast degradation of tetracycline hydrochloride and 4-epianhydrotetracycline hydrochloride in solution was retarded by controlling the autosampler temperature at 4 °C and using 0.1% H3 PO4 as diluent. The robustness of the method was tested starting with the maximum variations allowed in the US Pharmacopeia (USP) general chapter Chromatography <621>. The method was linear over the range 80-120% of the assay concentration (0.1 mg/mL) for tetracycline hydrochloride and 50-150% of the acceptance criteria specified in the individual USP monographs for 4-epianhydrotetracycline hydrochloride. The limit of quantification for 4-epianhydrotetracycline hydrochloride was 0.1 µg/mL, 20 times lower than the acceptance criteria. The method was specific, precise, accurate and robust. Copyright © 2014 John Wiley & Sons, Ltd.

  6. Kinetics of tetracycline, oxytetracycline, and chlortetracycline adsorption and desorption on two acid soils.

    PubMed

    Fernández-Calviño, David; Bermúdez-Couso, Alipio; Arias-Estévez, Manuel; Nóvoa-Muñoz, Juan Carlos; Fernández-Sanjurjo, Maria J; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-01-01

    The purpose of this work was to quantify retention/release of tetracycline, oxytetracycline, and chlortetracycline on two soils, paying attention to sorption kinetics and to implications of the adsorption/desorption processes on transfer of these pollutants to the various environmental compartments. We used the stirred flow chamber (SFC) procedure to achieve this goal. All three antibiotics showed high affinity for both soils, with greater adsorption intensity for soil 1, the one with the highest organic matter and Al and Fe oxides contents. Desorption was always <15%, exhibiting strong hysteresis in the adsorption/desorption processes. Adsorption was adequately modeled using a pseudo first-order equation with just one type of adsorption sites, whereas desorption was better adjusted considering both fast and slow sorption sites. The adsorption maximum (qmax) followed the sequence tetracycline > oxytetracycline > chlortetracycline in soil 1, with similar values for the three antibiotics and the sequence tetracycline > chlortetracycline > oxytetracycline in soil 2. The desorption sequences were oxytetracycline > tetracycline > chlortetracycline in soil 1 and oxytetracycline > chlortetracycline > tetracycline in soil 2. In conclusion, the SFC technique has yielded new kinetic data regarding tetracycline, oxytetracycline, and chlortetracycline adsorption/desorption on soils, indicating that it can be used to shed further light on the retention and transport processes affecting antibiotics on soils and other media, thus increasing knowledge on the behavior and evolution of these pharmaceutical residues in the environment.

  7. Isolation and characterisation of transport-defective substrate-binding mutants of the tetracycline antiporter TetA(B)

    PubMed Central

    Wright, David J.; Tate, Christopher G.

    2015-01-01

    The tetracycline antiporter TetA(B) is a member of the Major Facilitator Superfamily which confers tetracycline resistance to cells by coupling the efflux of tetracycline to the influx of protons down their chemical potential gradient. Although it is a medically important transporter, its structure has yet to be determined. One possibility for why this has proven difficult is that the transporter may be conformationally heterogeneous in the purified state. To overcome this, we developed two strategies to rapidly identify TetA(B) mutants that were transport-defective and that could still bind tetracycline. Up to 9 amino acid residues could be deleted from the loop between transmembrane α-helices 6 and 7 with only a slight decrease in affinity of tetracycline binding as measured by isothermal titration calorimetry, although the mutant was transport-defective. Scanning mutagenesis where all the residues between 2 and 389 were mutated to either valine, alanine or glycine (VAG scan) identified 15 mutants that were significantly impaired in tetracycline transport. Of these mutants, 12 showed no evidence of tetracycline binding by isothermal titration calorimetry performed on the purified transporters. In contrast, the mutants G44V and G346V bound tetracycline 4–5 fold more weakly than TetA(B), with Kds of 28 μM and 36 μM, respectively, whereas the mutant R70G bound tetracycline 3-fold more strongly (Kd 2.1 μM). Systematic mutagenesis is thus an effective strategy for isolating transporter mutants that may be conformationally constrained and which represent attractive targets for crystallisation and structure determination. PMID:26143388

  8. Genetic Basis and Clonal Population Structure of Antibiotic Resistance in Campylobacter jejuni Isolated From Broiler Carcasses in Belgium.

    PubMed

    Elhadidy, Mohamed; Miller, William G; Arguello, Hector; Álvarez-Ordóñez, Avelino; Duarte, Alexandra; Dierick, Katelijne; Botteldoorn, Nadine

    2018-01-01

    Human campylobacteriosis is the leading food-borne zoonosis in industrialized countries. This study characterized the clonal population structure, antimicrobial resistance profiles and occurrence of antimicrobial resistance determinants of a set of Campylobacter jejuni strains isolated from broiler carcasses in Belgium. Minimum inhibitory concentrations (MICs) against five commonly-used antibiotics (ciprofloxacin, nalidixic acid, tetracycline, gentamicin, and erythromycin) were determined for 204 C. jejuni isolates. More than half of the isolates were resistant to ciprofloxacin or nalidixic acid. In contrast, a lower percentage of screened isolates were resistant to gentamicin or erythromycin. C. jejuni isolates resistant to ciprofloxacin and/or nalidixic acid were screened for the substitution T86I in the quinolone resistance determining region (QRDR) of the gyrA gene, while C. jejuni isolates resistant to tetracycline were screened for the presence of the tet(O) gene. These resistance determinants were observed in most but not all resistant isolates. Regarding resistance to erythromycin, different mutations occurred in diverse genetic loci, including mutations in the 23S rRNA gene, the rplD and rplV ribosomal genes, and the intergenic region between cmeR and cmeABC . Interestingly, and contrary to previous reports, the A2075G transition mutation in the 23S rRNA gene was only found in one strain displaying a high level of resistance to erythromycin. Ultimately, molecular typing by multilocus sequence typing revealed that two sequence types (ST-824 and ST-2274) were associated to quinolones resistance by the presence of mutations in the gene gyrA ( p = 0.01). In addition, ST-2274 was linked to the CIP-NAL-TET-AMR multidrug resistant phenotype. In contrast, clonal complex CC-45 was linked to increased susceptibility to the tested antibiotics. The results obtained in this study provide better understanding of the phenotypic and the molecular basis of antibiotic

  9. Effect of citric acid, tetracycline, and doxycycline on instrumented periodontally involved root surfaces: A SEM study

    PubMed Central

    Chahal, Gurparkash Singh; Chhina, Kamalpreet; Chhabra, Vipin; Bhatnagar, Rakhi; Chahal, Amna

    2014-01-01

    Background: A surface smear layer consisting of organic and inorganic material is formed on the root surface following mechanical instrumentation and may inhibit the formation of new connective tissue attachment to the root surface. Modification of the tooth surface by root conditioning has resulted in improved connective tissue attachment and has advanced the goal of reconstructive periodontal treatment. Aim: The aim of this study was to compare the effects of citric acid, tetracycline, and doxycycline on the instrumented periodontally involved root surfaces in vitro using a scanning electron microscope. Settings and Design: A total of 45 dentin samples obtained from 15 extracted, scaled, and root planed teeth were divided into three groups. Materials and Methods: The root conditioning agents were applied with cotton pellets using the Passive burnishing technique for 5 minutes. The samples were then examined by the scanning electron microscope. Statistical Analysis Used: The statistical analysis was carried out using Statistical Package for Social Sciences (SPSS Inc., Chicago, IL, version 15.0 for Windows). For all quantitative variables means and standard deviations were calculated and compared. For more than two groups ANOVA was applied. For multiple comparisons post hoc tests with Bonferroni correction was used. Results: Upon statistical analysis the root conditioning agents used in this study were found to be effective in removing the smear layer, uncovering and widening the dentin tubules and unmasking the dentin collagen matrix. Conclusion: Tetracycline HCl was found to be the best root conditioner among the three agents used. PMID:24744541

  10. Tetracycline residues and tetracycline resistance genes in groundwater impacted by swine production facilities

    USGS Publications Warehouse

    Mackie, R.I.; Koike, S.; Krapac, I.; Chee-Sanford, J.; Maxwell, Susan; Aminov, R.I.

    2006-01-01

    Antibiotics are used at therapeutic levels to treat disease; at slightly lower levels as prophylactics; and at low, subtherapeutic levels for growth promotion and improvement of feed efficiency. Over 88% of swine producers in the United States gave antimicrobials to grower/finisher pigs in feed as a growth promoter in 2000. It is estimated that ca. 75% of antibiotics are not absorbed by animals and are excreted in urine and feces. The extensive use of antibiotics in swine production has resulted in antibiotic resistance in many intestinal bacteria, which are also excreted in swine feces, resulting in dissemination of resistance genes into the environment.To assess the impact of manure management on groundwater quality, groundwater samples have been collected near two swine confinement facilities that use lagoons for manure storage and treatment. Several key contaminant indicators-including inorganic ions, antibiotics, and antibiotic resistance genes-were analyzed in groundwater collected from the monitoring wells. Chloride, ammonium, potassium, and sodium were predominant inorganic constituents in the manure samples and served as indicators of groundwater contamination. Based on these analyses, shallow groundwater has been impacted by lagoon seepage at both sites. Liquid chromatography-mass spectroscopy (LC-MS) was used to measure the dissolved concentrations of tetracycline, chlortetracycline, and oxytetracycline in groundwater and manure. Although tetracyclines were regularly used at both facilities, they were infrequently detected in manure samples and then at relatively trace concentrations. Concentrations of all tetracyclines and their breakdown products in the groundwater sampled were generally less than 0.5 ??g/L.Bacterial tetracycline resistance genes served as distinct genotypic markers to indicate the dissemination and mobility of antibiotic resistance genes that originated from the lagoons. Applying PCR to genomic DNA extracted from the lagoon and

  11. Treatment of testicular hydrocele with tetracycline sclerotherapy.

    PubMed

    Ozkan, S; Bircan, K; Ozen, H

    1990-01-01

    Fifteen patients with primary hydrocele of the testis were treated by aspiration and injection of tetracycline. Only 5 patients (33.3%) were cured by a single injection of tetracycline. Furthermore, 46.6% of our patients experienced severe scrotal pain, three of whom required open surgery. We do not recommend single injection tetracycline therapy, and further injections were not performed due to severe side effects.

  12. Class 1 integrons and plasmid-mediated multiple resistance genes of the Campylobacter species from pediatric patient of a university hospital in Taiwan.

    PubMed

    Chang, Yi-Chih; Tien, Ni; Yang, Jai-Sing; Lu, Chi-Cheng; Tsai, Fuu-Jen; Huang, Tsurng-Juhn; Wang, I-Kuan

    2017-01-01

    The Campylobacter species usually causes infection between humans and livestock interaction via livestock breeding. The studies of the Campylobacter species thus far in all clinical isolates were to show the many kinds of antibiotic phenomenon that were produced. Their integrons cause the induction of antibiotic resistance between bacterial species in the Campylobacter species. The bacterial strains from the diarrhea of pediatric patient which isolated by China Medical University Hospital storage bank. These isolates were identified by MALDI-TOF mass spectrometry. The anti-microbial susceptibility test showed that Campylobacter species resistant to cefepime, streptomycin, tobramycin and trimethoprim/sulfamethoxazole (all C. jejuni and C. coli isolates), ampicillin (89% of C. jejuni ; 75% of C. coli ), cefotaxime (78% of C. jejuni ; 100% of C. coli ), nalidixic acid (78% of C. jejuni ; 100% of C. coli ), tetracycline (89% of C. jejuni ; 25% C. coli ), ciprofloxacin (67% of C. jejuni ; 50% C. coli ), kanamycin (33% of C. jejuni ; 75% C. coli ) and the C. fetus isolate resisted to ampicillin, cefotaxime, nalidixic acid, tetracycline, ciprofloxacin, kanamycin by disc-diffusion method. The effect for ciprofloxacin and tetracycline of the Campylobacter species was tested using an E-test. The tet, erm , and integron genes were detected by PCR assay. According to the sequencing analysis (type I: dfr12 - gcuF - aadA2 genes and type II: dfrA7 gene), the cassette type was identified. The most common gene cassette type (type I: 9 C. jejuni and 2 C. coli isolates; type II: 1 C. coli isolates) was found in 12 class I integrase-positive isolates. Our results suggested an important information in the latency of Campylobacter species with resistance genes, and irrational antimicrobial use should be concerned.

  13. The attachment of V79 and human periodontal ligament fibroblasts on periodontally involved root surfaces following treatment with EDTA, citric acid, or tetracycline HCL: an SEM in vitro study.

    PubMed

    Chandra, R Viswa; Jagetia, Ganesh Chandra; Bhat, K Mahalinga

    2006-02-15

    The present in vitro study has been designed to establish and compare the effects of citric acid, EDTA, and tetracycline HCl on human periodontally diseased roots on the structure, attachment, and orientation of V79 (primary Chinese hamster lung fibroblasts) cells and human periodontal ligament fibroblasts (HPDL). Commercially available V79 cells and HPDL derived from healthy human third molars were used in this study. These fibroblasts were left in solution for seven days in order to attain confluence. Forty single-rooted teeth were obtained from patients diagnosed with periodontitis. The crown part was removed under constant irrigation and the root was split vertically into two equal halves, thus, yielding 80 specimens. Following scaling and root planing, the specimens were washed with phosphate buffered saline (PBS) and kept in 50 microg/ml gentamycin sulphate solution for 24 hours. The root pieces were then treated as follows: citric acid at pH 1, 24% EDTA, or with a 10% solution of tetracycline HCl and were then placed in V79 fibroblast cultures and HPDL cultures. The specimens were harvested after four weeks and were fixed in 2.5% glutaraldehyde in PBS before preparation for scanning electron microscopy (SEM). The behavior of V79 cells was similar to that of human periodontal ligament cells on root conditioned surfaces. V79 and HPDL showed a healthy morphology on root surfaces treated with citric acid and EDTA and a relatively unhealthy appearance on root surfaces treated with tetracycline HCl and distilled water (control group). The results suggest the use of citric acid and EDTA as root conditioning agents favorably affects the migration, attachment, and morphology of fibroblasts on human root surfaces, which may play a significant role in periodontal healing and regeneration.

  14. 21 CFR 520.2345c - Tetracycline boluses.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... tetracycline, bacterial enteritis caused by E. coli, and salmonella organisms susceptible to tetracycline. (ii...

  15. 21 CFR 520.2345c - Tetracycline boluses.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia caused by Pasteurella spp... tetracycline, bacterial enteritis caused by E. coli, and salmonella organisms susceptible to tetracycline. (ii...

  16. Effect of tetracyclines and 4-epiderivatives on the ureter

    PubMed Central

    Arrigoni, E.; Benzi, G.; Ferrara, A.

    1972-01-01

    1. The effect of tetracyclines on the isolated dog ureter is dependent on: (a) the tetracyclines used—mepicycline and doxycycline antagonizing, and tetracycline and rolitetracycline increasing the contractor action of barium chloride; (b) the percentage of 4-epiderivatives in the tetracyclines used—the higher the epiderivative concentration, the smaller the effect of mepicycline or doxycycline, and the greater the action of tetracycline or rolitetracycline. 2. In vivo the addition of the antibiotics into the renal pelvis shows no significant differences between the various tetracyclines or different 4-epiderivative concentrations on the intra-ureteral flow of the dog or guinea-pig. 3. Intravenous injection of mepicycline or doxycycline does not induce a significant change in the intra-ureteral flow, while intravenous administration of tetracycline or rolitetracycline produces a triphasic response: (a) a marked decrease of the intra-ureteral flow for a few minutes; (b) a return to the control condition for 30-60 min; and (c) a lesser but persistent decrease in flow for 60-120 minutes. In the first phase the ureteral smooth muscle is directly affected by the antibiotics circulating in the blood, while in the third phase the tetracyclines act via the intra-ureteral mucosa. 4. Neurogenic effects on the ureter-bladder junction in vivo are not affected by the tetracyclines tested. PMID:4625269

  17. Antimicrobial Susceptibility of Campylobacter Cuniculorum Isolated from Rabbits Reared in Intensive and Rural Farms

    PubMed Central

    Piva, Silvia; Florio, Daniela; Mion, Domenico; Zanoni, Renato Giulio

    2016-01-01

    The present study aimed to investigate the antimicrobial susceptibility in Campylobacter cuniculorum. To do so, 29 isolates from rabbits reared in 18 intensive and 11 rural farms not epidemiologically correlated were tested. Minimum inhibitory concentration of 8 antimicrobial agents was determined using the agar dilution method recommended by the Clinical and Laboratory Standards Institute (Wayne, PA, USA), modified – for what supplements in the base medium and incubation conditions concern – for C. cuniculorum isolates. The isolates obtained from rural farming resulted susceptible to all the antimicrobial agents tested, with the exception of one isolate resistant to nalidixic acid. All the isolates obtained from intensively farmed rabbits were sensitive to chloramphenicol and ampicillin; 16 isolates were resistant to tetracycline; 15 to nalidixic acid and erythromycin; 13 and 10 isolates to ciprofloxacin and enrofloxacin, respectively; and only 1 to gentamicin. The resistance of several isolates to macrolides and fluoroquinolones, which are the drugs of choice in treatment of human campylobacteriosis, could pose a risk to human health if a pathogenic role of C. cuniculorum was demonstrated. PMID:27853713

  18. [Anaerobic digestion of animal manure contaminated by tetracyclines].

    PubMed

    Tong, Zi-Lin; Liu, Yuan-Lu; Hu, Zhen-Hu; Yuan, Shou-Jun

    2012-03-01

    Anaerobic digestion of pig manure spiked with tetracycline (TC) and chlortetracycline (CTC) and the degradation of the two antibiotics during the anaerobic digestion at 35 degrees C were investigated. The results indicate that propionate was the main volatile fatty acid produced during the anaerobic digestion followed by acetate. Compared with the CTC addition, TC + CTC addition showed obvious inhibitory effect on the hydrolysis and acidification of easily digestible organic components of pig manure. The cumulative methane production of TC, CTC, TC + CTC and CK2 during anaerobic digestion was 386.4 mL, 406.0 mL, 412.1 mL and 464.6 mL, respectively. Degradation of TC and CTC followed the first-order kinetic equation. The half-life of TC and CTC was 14-18 days and 10 days, respectively. After the treatment of 45-day anaerobic digestion, the degradation efficiency of TC was 88.6%-91.6% with 97.7%-98.2% of CTC. Therefore, anaerobic digestion shows the benefit on the management of animal manures contaminated by tetracyclines.

  19. Simultaneous determination of five tetracycline and macrolide antibiotics in feeds using HPCE.

    PubMed

    Tong, Jing; Rao, Qinxiong; Zhu, Kui; Jiang, Zhigang; Ding, Shuangyang

    2009-12-01

    This work demonstrates the potential of HPCE in the analysis of antibiotics in a complex matrix such as feedstuffs. Using 20 mM citric acid-40 mM Na(2)HPO(4) buffer (pH 2.65), the five antibiotics, tetracycline, oxytetracycline, doxycycline, tilmicosin, and tylosin were successfully separated at 30 kV in a 64.5 cm x 75 microm id capillary. Good repeatability, stability, and reliability of the method were supported by <10% CV with mean recoveries of >70%, and the limit of detection of the five analytes was 0.5-1 mg/kg. It was for the first time that a capillary electrophoretic method was employed to simultaneously detect five tetracycline and macrolide antibiotics in animal feeds.

  20. Prevalence of gyrA Mutations in Nalidixic Acid-Resistant Strains of Salmonella Enteritidis Isolated from Humans, Food, Chickens, and the Farm Environment in Brazil.

    PubMed

    Campioni, Fábio; Souza, Roberto Antonio; Martins, Vinicius Vicente; Stehling, Eliana Guedes; Bergamini, Alzira Maria Morato; Falcão, Juliana Pfrimer

    2017-06-01

    Salmonella Enteritidis strains that are resistant to nalidixic acid and exhibit reduced susceptibility to fluoroquinolones have been increasing worldwide. In Brazil, few studies have been conducted to elucidate the quinolone resistance mechanisms of S. Enteritidis strains. This study analyzed the profile of gyrA, gyrB, parC, and parE mutations and plasmid-mediated quinolone resistance (PMQR) mechanisms in S. Enteritidis Nal R strains isolated in Brazil. Moreover, the minimum inhibitory concentrations (MICs) of ciprofloxacin were evaluated in 84 Nal R strains and compared with 20 Nal S strains. The mutation profiles of the gyrA gene were accessed by high-resolution melting analysis and gyrB, parC, and parE by quinolone resistance-determining region sequencing. The MICs of ciprofloxacin were accessed with Etest ® . The strains were divided into five gyrA melting profiles. The Nal R strains exhibited the following amino acid substitutions: Ser97→Pro, Ser83→Phe, Asp87→Asn, or Asp87→Tyr. The average MICs of ciprofloxacin was 0.006 μg/ml in the Nal S and 0.09 μg/ml in the Nal R strains. No points of mutation were observed in the genes gyrB, parC, and parE. The qnrB gene was found in two strains. In conclusion, the reduced susceptibility to ciprofloxacin observed in Nal R strains may cause treatment failures once this drug is commonly used to treat Salmonella infections. Moreover, this reduced susceptibility in these Brazilian strains was provided by target alteration of gene gyrA and not by mobile elements, such as resistance plasmids.

  1. Tetracycline and Pregnancy

    MedlinePlus

    ... to a group of antibiotics that includes minocycline, oxytetracycline, doxycycline. In general, the information in this fact ... other medications in this group such as minocycline, oxytetracycline, or doxycycline instead of tetracycline? Does that still ...

  2. 21 CFR 520.2345e - Tetracycline oral liquid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sensitive to tetracycline hydrochloride, such as bacterial gastroenteritis due to Escherichia coli and... susceptible to tetracycline hydrochloride, such as bacterial gastroenteritis due to E. coli and urinary tract...

  3. 21 CFR 520.2345e - Tetracycline oral liquid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... sensitive to tetracycline hydrochloride, such as bacterial gastroenteritis due to Escherichia coli and... susceptible to tetracycline hydrochloride, such as bacterial gastroenteritis due to E. coli and urinary tract...

  4. Assessing the antibiotic susceptibility of freshwater Cyanobacteria spp.

    PubMed Central

    Dias, Elsa; Oliveira, Micaela; Jones-Dias, Daniela; Vasconcelos, Vitor; Ferreira, Eugénia; Manageiro, Vera; Caniça, Manuela

    2015-01-01

    Freshwater is a vehicle for the emergence and dissemination of antibiotic resistance. Cyanobacteria are ubiquitous in freshwater, where they are exposed to antibiotics and resistant organisms, but their role on water resistome was never evaluated. Data concerning the effects of antibiotics on cyanobacteria, obtained by distinct methodologies, is often contradictory. This emphasizes the importance of developing procedures to understand the trends of antibiotic susceptibility in cyanobacteria. In this study we aimed to evaluate the susceptibility of four cyanobacterial isolates from different genera (Microcystis aeruginosa, Aphanizomenon gracile, Chrisosporum bergii, Planktothix agradhii), and among them nine isolates from the same specie (M. aeruginosa) to distinct antibiotics (amoxicillin, ceftazidime, ceftriaxone, kanamycine, gentamicine, tetracycline, trimethoprim, nalidixic acid, norfloxacin). We used a method adapted from the bacteria standard broth microdilution. Cyanobacteria were exposed to serial dilution of each antibiotic (0.0015–1.6 mg/L) in Z8 medium (20 ± 1°C; 14/10 h L/D cycle; light intensity 16 ± 4 μEm−2s−1). Cell growth was followed overtime (OD450nm/microscopic examination) and the minimum inhibitory concentrations (MICs) were calculated for each antibiotic/isolate. We found that β-lactams exhibited the lower MICs, aminoglycosides, tetracycline and norfloxacine presented intermediate MICs; none of the isolates were susceptible to trimethoprim and nalidixic acid. The reduced susceptibility of all tested cyanobacteria to some antibiotics suggests that they might be naturally non-susceptible to these compounds, or that they might became non-susceptible due to antibiotic contamination pressure, or to the transfer of genes from resistant bacteria present in the environment. PMID:26322027

  5. EMJH medium with 5-fluorouracil and nalidixic acid associated with serial dilution technique used to recover Leptospira spp from experimentally contaminated bovine semen

    PubMed Central

    Miraglia, Fabiana; de Moraes, Zenaide Maria; Melville, Priscilla Anne; Dias, Ricardo Augusto; Vasconcellos, Silvio Arruda

    2009-01-01

    Bovine semen experimentally contaminated with Leptospira santarosai serovar Guaricura was submitted to the modified EMJH medium with 5-fluorouracil (300mg/L) and nalidixic acid (20mg/L), named as “selective medium” and using the serial dilution technique, in order to evaluate the percentage of recovery of the added microorganism. The selective EMJH medium was found with higher percentage of recovery of leptospiras and minor losses of samples due to contamination with opportunistic microorganisms than the non-selective EMJH medium: 151/376 (40.0%) of positive growth; and 38/376 (10.0%) contamination and 58/376 (15%) and 129/376 (34.0%), respectively. These results were statistically significant (p<0. 0001; Fisher). Differences were found when the frequencies of positive leptospires recovery have been compared in the serial dilution technique (10-1 to 10-4) between the selective and non-selective media at different dilution factors. At 1/10th dilution the percentages found were (0%, 0/80) and (38%, 30/80), at 1/100th dilution, (3%, 2/80) and (49%, 39/ 80) and at 1/1,000th dilution, (25%, 20/80) and (50%, 40/80), respectively. The percentage of recovery of leptospires was found to be directly proportional to the dilution used. The methodology of the serial dilution technique (setting at least three dilutions) and the use of selective EMJH medium have been found to be efficient for the isolation of leptospires from the bovine semen samples. PMID:24031342

  6. Multidrug-resistant Commensal Escherichia coli in Children, Peru and Bolivia

    PubMed Central

    Pallecchi, Lucia; Benedetti, Marta; Fernandez, Connie; Vallejos, Yolanda; Guzman, Elisa; Villagran, Ana Liz; Mantella, Antonia; Lucchetti, Chiara; Bartalesi, Filippo; Strohmeyer, Marianne; Bechini, Angela; Gamboa, Herlan; Rodríguez, Hugo; Falkenberg, Torkel; Kronvall, Göran; Gotuzzo, Eduardo; Paradisi, Franco; Rossolini, Gian Maria

    2006-01-01

    Using a rapid screening method, we investigated the prevalence of fecal carriage of antimicrobial drug–resistant Escherichia coli in 3,174 healthy children from 4 urban settings in Peru and Bolivia. High resistance rates were observed for ampicillin (95%), trimethoprim-sulfamethoxazole (94%), tetracycline (93%), streptomycin (82%), and chloramphenicol (70%). Lower resistance rates were observed for nalidixic acid (35%), kanamycin (28%), gentamicin (21%), and ciprofloxacin (18%); resistance to ceftriaxone and amikacin was uncommon (<0.5%). In a random sample of 1,080 resistant E. coli isolates, 90% exhibited a multidrug-resistance (MDR) phenotype. The 2 most common MDR phenotypes (ampicillin/tetracycline/trimethoprim-sulfamethoxazole and ampicillin/tetracycline/trimethoprim-sulfamethoxazole/chloramphenicol) could be transferred en bloc in conjugation experiments. The most common acquired resistance genes were blaTEM, tet(A), tet(B), drfA8, sul1, sul2, and catI. These findings underscore the magnitude of the problem of antimicrobial drug resistance in low-resource settings and the urgent need for surveillance and control of this phenomenon. PMID:16707045

  7. Monitoring tetracycline through a solid-state nanopore sensor

    NASA Astrophysics Data System (ADS)

    Zhang, Yuechuan; Chen, Yanling; Fu, Yongqi; Ying, Cuifeng; Feng, Yanxiao; Huang, Qimeng; Wang, Chao; Pei, De-Sheng; Wang, Deqiang

    2016-06-01

    Antibiotics as emerging environmental contaminants, are widely used in both human and veterinary medicines. A solid-state nanopore sensing method is reported in this article to detect Tetracycline, which is based on Tet-off and Tet-on systems. rtTA (reverse tetracycline-controlled trans-activator) and TRE (Tetracycline Responsive Element) could bind each other under the action of Tetracycline to form one complex. When the complex passes through nanopores with 8 ~ 9 nanometers in diameter, we could detect the concentrations of Tet from 2 ng/mL to 2000 ng/mL. According to the Logistic model, we could define three growth zones of Tetracycline for rtTA and TRE. The slow growth zone is 0-39.5 ng/mL. The rapid growth zone is 39.5-529.7 ng/mL. The saturated zone is > 529.7 ng/mL. Compared to the previous methods, the nanopore sensor could detect and quantify these different kinds of molecule at the single-molecule level.

  8. Occurrence of Salmonella spp. in broiler chicken carcasses and their susceptibility to antimicrobial agents

    PubMed Central

    Duarte, Dalila Angélica Moliterno; Ribeiro, Aldemir Reginato; Vasconcelos, Ana Mércia Mendes; Santos, Sylnei Barros; Silva, Juliana Vital Domingos; de Andrade, Patrícia Lúcia Arruda; de Arruda Falcão, Lúcia Sadae Pereira da Costa

    2009-01-01

    The present study was carried out to evaluate the occurrence of Salmonellae in broiler chicken carcasses and to determine the antimicrobial resistance profile of the isolated strains. Twenty-five out of the 260 broiler chicken carcasses samples (9.6%) were positive for Salmonella. S. Enteritidis was the most frequent serovar. Nineteen Salmonella isolates were tested for antimicrobial resistance, and the results indicated that 94.7% were resistant to at least one antimicrobial agent. Resistance to streptomycin (73.7%), nitrofurantoin (52.3%), tetracycline (31.6%), and nalidixic acid (21%) were the prevalent amongst Salmonella strains tested. PMID:24031401

  9. Treatment of hydrocele testis by injection of tetracycline.

    PubMed

    Miskowiak, J; Christensen, A B

    1988-01-01

    In a prospective study 27 hydroceles were treated with single aspiration and injection of 500 mg tetracycline. The median observation period was 6 months (range 3-15 months). One month after therapy 9 recurrences were observed; but 5 disappeared spontaneously during the next 2 months, giving an overall success rate of 85% (95% confidence limits 66-96%). No serious complications occurred. Dilution of tetracycline in lidocaine prevented acute scrotal pain. Sclerotherapy with tetracycline is efficient, easy and inexpensive and, therefore, economical and beneficial for the patient.

  10. Lack of Doxycycline Antimalarial Prophylaxis Impact on Staphylococcus aureus Tetracycline Resistance

    PubMed Central

    Mende, Katrin; Beckius, Miriam L.; Zera, Wendy C.; Yu, Xin; Li, Ping; Tribble, David R.; Murray, Clinton K.

    2016-01-01

    There is concern that susceptibility of Staphylococcus aureus to tetracyclines may decrease due to use of antimalarial prophylaxis (doxycycline). We examined characteristics related to tetracycline resistance, including doxycycline exposure, in S. aureus isolates collected via admission surveillance swabs and inpatient clinical cultures from United States military personnel injured during deployment (June 2009-January 2012). Tetracycline class resistance was determined using antimicrobial susceptibility testing. The first S. aureus isolate from 168 patients were analyzed, of which 38 (23%) isolates were resistant to tetracyclines (class). Tetracycline-resistant isolates had a higher proportion of resistance to clindamycin (p=0.019) compared to susceptible isolates. There was no significant difference in tetracycline resistance between isolates collected from patients with and without antimalarial prophylaxis; however, significantly more isolates had tet(M) resistance genes in the doxycycline exposure group (p=0.031). Despite 55% of the patients receiving doxycycline as antimalarial prophylaxis, there was no association with resistance to tetracyclines. PMID:27460426

  11. Antibiotic Susceptibility, Genetic Diversity, and the Presence of Toxin Producing Genes in Campylobacter Isolates from Poultry.

    PubMed

    Lee, Jeeyeon; Jeong, Jiyeon; Lee, Heeyoung; Ha, Jimyeong; Kim, Sejeong; Choi, Yukyung; Oh, Hyemin; Seo, Kunho; Yoon, Yohan; Lee, Soomin

    2017-11-17

    This study examined antibiotic susceptibility, genetic diversity, and characteristics of virulence genes in Campylobacter isolates from poultry. Chicken ( n = 152) and duck ( n = 154) samples were collected from 18 wet markets in Korea. Campylobacter spp. isolated from the carcasses were identified by PCR. The isolated colonies were analyzed for antibiotic susceptibility to chloramphenicol, amikacin, erythromycin, tetracycline, ciprofloxacin, nalidixic acid, and enrofloxacin. The isolates were also used to analyze genetic diversity using the DiversiLab TM system and were tested for the presence of cytolethal distending toxin ( cdt ) genes. Campylobacter spp. were isolated from 45 poultry samples out of 306 poultry samples (14.7%) and the average levels of Campylobacter contamination were 22.0 CFU/g and 366.1 CFU/g in chicken and duck samples, respectively. Moreover, more than 90% of the isolates showed resistance to nalidixic acid and ciprofloxacin. Genetic correlation analysis showed greater than 95% similarity between 84.4% of the isolates, and three cdt genes ( cdtA , cdtB , and cdtC ) were present in 71.1% of Campylobacter isolates. These results indicate that Campylobacter contamination should be decreased to prevent and treat Campylobacter foodborne illness.

  12. Phosphotungstic acid binding in situ to K4Nb6O17 for the effective adsorption-photocatalytic removal of tetracycline

    NASA Astrophysics Data System (ADS)

    Gu, Huimin; Lang, Junyu; Ma, Yuli; Gu, Huayu; Song, Yanyong; Chai, Zhanli; Li, Guangshe; Wang, Xiaojing

    2018-05-01

    In this investigation, phosphotungstic acid (H3PW12O40) was successfully self-assembly implanted into the interspace of K4Nb6O17 nanosheet via an impregnation method to form an adsorption-photocatalytic composite, in which n-type semiconductor K4Nb6O17 was selected as photo-electron emitter and H3PW12O40 was particularly used as an electronic transmitter. By characterizing with X-ray diffraction (XRD), transmission (TEM), scan electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and FT-IR spectrum (FT-IR), it confirmed that H3PW12O40 (HPW) was converted to the insoluble tiny particles of K3PW12O40 (KPW) with the remained primary Keggin group via an ion-exchanged H+ of HPW with K+ in K4Nb6O17 in the implanted process and was firmly bound to the surface of K4Nb6O17 to form well sandwich structure. UV-vis diffuse reflectance spectroscopy revealed that the band gap of K4Nb6O17-K3PW12O40 have a slight red shift compared with the single K4Nb6O17. Its adsorption-photocatalytic properties were evaluated with the removal of tetracycline as model reaction. Compared with pure K4Nb6O17, tetracycline removal rate can be significantly improved for the as-prepared sandwich. Importantly, the removal could still maintain 70% after five reuses in recycle tests at an acidic solution, inferring a good stability which was mainly ascribed to the formation of water-insoluble K3PW12O40. The separation and transfer process of photogenerated electrons were investigated by surface photovoltage spectroscopy (SPV). It proposed that the KPW anchored firmly on the interlayers of K4Nb6O17 through a O-K-O bridge plays a significantly role in promoting the separation of the photogenerated carriers and preventing the leakage and agglomeration of HPW. The present results showed that the strategy of the phosphotungstic acid binding in situ to K4Nb6O17 was favorable to promote the hetero-photocatalytic efficiency as well as reusability. [Figure not available: see fulltext.

  13. Resistance to tetracycline and β-lactams and distribution of resistance markers in enteric microorganisms and pseudomonads isolated from the oral cavity

    PubMed Central

    RAMOS, Marcelle Marie Buso; GAETTI-JARDIM, Ellen Cristina; GAETTI-JARDIM, Elerson

    2009-01-01

    ABSTRACT This study evaluated the occurrence of enteric bacteria and pseudomonads resistant to tetracycline and β-lactams in the oral cavity of patients exhibiting gingivitis (n=89), periodontitis (n=79), periodontally healthy (n=50) and wearing complete dentures (n=41). Microbial identification and presence of resistance markers associated with the production of β-lactamases and tetracycline resistance were performed by using biochemical tests and PCR. Susceptibility tests were carried out in 201 isolates of enteric cocci and rods. Resistance to ampicillin, amoxicillin/clavulanic acid, imipenem, meropenem and tetracycline was detected in 57.4%, 34.6%, 2.4%, 1.9% and 36.5% of the isolates, respectively. β-lactamase production was observed in 41.2% of tested microorganisms, while the most commonly found β-lactamase genetic determinant was gene blaTEM. Tetracycline resistance was disseminated and a wide scope of tet genes were detected in all studied microbial genus. PMID:21499650

  14. Surface effects and desorption of tetracycline supramolecular complex on bovine dentine.

    PubMed

    Pataro, A L; Franco, C F; Santos, V R; Cortés, M E; Sinisterra, R D

    2003-03-01

    The aim of this in vitro study was to evaluate the antimicrobial activity, the substantivity, and surface effects of the inclusion compound tetracycline: beta-cyclodextrin on bovine roots. The antimicrobial activity was assessed by dentine slabs which had been immersed in the inclusion complex in concentrations 8.0%, 4.0%, 2.0%, 1.0%, 0.5% and 0.25% for 5min compared to a control of tetracycline hydrochloride. Each slab was tested in a broth of overnight culture of Actinobacillus actinomycetemcomitans (Y4-FDC). The inclusion complex significantly inhibited the A. actinomycetemcomitans (p<0.01) verified at concentrations from 1.0% to 8.0%. The substantivity of tetracycline was evaluated by the measure of desorption from the slabs previously immersed in solution samples and removed at 24h intervals. The tetracycline encapsulated in beta-cyclodextrin showed a flow rate near to zero order in comparison to free tetracycline. The surface morphology determined by SEM showed a more homogeneous and integrated layer with the complex compared to the effect of free tetracycline. We concluded that the root surfaces treated with tetracycline: beta-cyclodextrin release lower concentrations of active drug over 5 days at inhibitory concentrations against A. actinomycetemcomitans with enhanced disponibility in comparison to tetracycline.

  15. [Cetyltrimethylammonium bromide for fluorescence enhancement of anhydrotetracycline hydrochloride and iso-tetracycline].

    PubMed

    Zha, Jian-peng; Lin, Ying; Yang, Xing-hui; Hou, Hai-ni; Wei, Tie-jun; Chen, Xing-li

    2002-06-01

    Fluorescence enhancement of anhydrotetracycline hydrochloride and iso-tetracycline has been described. The fluorescence intensities of anhydrotetracycline hydrochloride and iso-tetracycline with cetyltrimethylammonium bromide (CTMAB) enhanced by micellar solution have been examined. It is found that fluorescence enhancement of anhydrotetracycline hydrochloride and iso-tetracycline depends on the concentration of CTMAB and pH of the solution. It can be used to develop sensitive methods for the determination of tetracycline hydrochloride and its decomposition product.

  16. Competitive adsorption/desorption of tetracycline, oxytetracycline and chlortetracycline on two acid soils: Stirred flow chamber experiments.

    PubMed

    Fernández-Calviño, David; Bermúdez-Couso, Alipio; Arias-Estévez, Manuel; Nóvoa-Muñoz, Juan Carlos; Fernández-Sanjurjo, Maria J; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-09-01

    The objective of this work was to study the competitive adsorption/desorption of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) on two acid soils. We used the stirred flow chamber technique to obtain experimental data on rapid kinetic processes affecting the retention/release of the antibiotics. Both adsorption and desorption were higher on soil 1 (which showed the highest carbon, clay and Al and Fe oxides content) than on soil 2. Moreover, hysteresis affected the adsorption/desorption processes. Experimental data were fitted to a pseudo-first order equation, resulting qamax (adsorption maximum) values that were higher for soil 1 than for soil 2, and indicating that CTC competed with TC more intensely than OTC in soil 1. Regarding soil 2, the values corresponding to the adsorption kinetics constants (ka) and desorption kinetics constants for fast sites (kd1), followed a trend inverse to qamax and qdmax respectively. In conclusion, competition affected adsorption/desorption kinetics for the three antibiotics assayed, and thus retention/release and subsequent transport processes in soil and water environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Comparison of Antimicrobial Properties of Nano Quinolone with its Microscale Effects

    NASA Astrophysics Data System (ADS)

    Behbahani, G. Rezaie; Sadr, M. Hossaini; Nabipour, H.; Behbahani, H. Rezaei; Vahedpour, M.; Barzegar, L.

    2013-06-01

    Nano nalidixic acid was prepared by ultrasonic method in carbon tetrachloride. Nano nalidixic acid (quinolone antibiotic) was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscope (SEM). The antibacterial activities of nano nalidixic acid were tested against microorganisms and compared with the microscale drug. The results show that nano nalidixic acid has good inhibitory properties against two Gram-positive species, Staphylococcus aureus and Bacillus subtilis. Nano nalidixic acid also showed good antifungal activity against Candida albicans. Nano nalidixic acid can be injected into the human body as a decontaminating agent to prevent the growth of harmful microorganisms more effectively than the micro-sized drug.

  18. Intracellular and membrane-damaging activities of methyl gallate isolated from Terminalia chebula against multidrug-resistant Shigella spp.

    PubMed

    Acharyya, Saurabh; Sarkar, Prodipta; Saha, Dhira R; Patra, Amarendra; Ramamurthy, T; Bag, Prasanta K

    2015-08-01

    Shigella spp. (Shigella dysenteriae, Shigella flexneri, Shigella boydii and Shigella sonnei) cause bacillary dysentery (shigellosis), which is characterized by bloody mucous diarrhoea. Although a variety of antibiotics have been effective for treatment of shigellosis, options are becoming limited due to globally emerging drug resistance. In the present study, in vitro antibacterial activity of methyl gallate (MG) isolated from Terminalia chebula was determined by performing MIC, minimal bactericidal concentration (MBC) and time-kill kinetic studies. Bacterial membrane-damaging activity of MG was determined by membrane perturbation and transmission electron microscopy (TEM). Cellular drug accumulation, cell infection and assessment of intracellular activities of MG and reference antibiotics were performed using HeLa cell cultures. The bactericidal activity of MG against multidrug-resistant (MDR) Shigella spp. in comparison with other commonly used drugs including fluoroquinolone was demonstrated here. TEM findings in the present study revealed that MG caused the total disintegration of inner and outer membranes, and leakage of the cytoplasmic contents of S. dysenteriae. The level of accumulation of MG and tetracycline in HeLa cells incubated for 24  h was relatively higher than that of ciprofloxacin and nalidixic acid (ratio of intracellular concentration/extracellular concentration of antibiotic for MG and tetracycline>ciprofloxacin and nalidixic acid). The viable number of intracellular S. dysenteriae was decreased in a time-dependent manner in the presence of MG (4 × MBC) and reduced to zero within 20  h. The significant intracellular activities of MG suggested that it could potentially be used as an effective antibacterial agent for the treatment of severe infections caused by MDR Shigella spp.

  19. Failure of tetracycline as a biomarker in batch-marking juvenile frogs

    USGS Publications Warehouse

    Hatfield, Jeffrey S.; Henry, Paula F.P.; Olsen, Glenn H.; Paul, M.M.; Hammerschlag, Richard S.

    2001-01-01

    Recent widespread amphibian declines call for better techniques to assess population dynamics. Tetracycline as a biomarker in capture-recapture studies is one technique used successfully in fish, reptiles, and mammals. A two-phase experimental study was conducted to evaluate tetracycline as a biomarker in green frogs (Rana clamitans) and pickerel frogs (Rana palustris). In the first experimental phase tadpoles were exposed to water containing either 250 mg/l or 500 mg/l tetracycline for a period of 24 hr. During the second phase, juvenile frogs were exposed to tetracycline in water at 500 mg/l or given injections of tetracycline at the dose rate of 100 mg/kg body weight. At selected times several weeks later, under tricaine methanesulfonate anesthesia, a toe was surgically excised from each animal, sectioned and viewed under an ultraviolet microscope. No significant differences were found between the various treatments and control animals (untreated). Therefore, the use of tetracycline as a biomarker in anurans using these techniques is not recommended.

  20. Simultaneously efficient adsorption and photocatalytic degradation of tetracycline by Fe-based MOFs.

    PubMed

    Wang, Dongbo; Jia, Feiyue; Wang, Hou; Chen, Fei; Fang, Ying; Dong, Wenbo; Zeng, Guangming; Li, Xiaoming; Yang, Qi; Yuan, Xingzhong

    2018-06-01

    Recently, Fe-based metal-organic frameworks (MOFs) have attracted increasing attention and been widely used. To date, however, it is unknown whether they can be employed to degrade tetracycline, one of the most widely used antibiotics. This work therefore aims to provide such support by comparing the performance of three Fe-based MOFs (namely, Fe-MIL-101, Fe-MIL-100, and Fe-MIL-53) in removing tetracycline. Experimental results showed that Fe-MIL-101 exhibited the best performance in tetracycline removal, with 96.6% of tetracycline being removed (initial tetracycline concentration at 50 mg/L) while Fe-MIL-100 and Fe-MIL-53 removed 57.4% and 40.6% under the same conditions. Additionally, the effects of adding dosage, adsorption time, and initial concentration of tetracycline on degradation efficiency were examined. It was found that the adsorption and photocatalytic degradation effect was better with the increase of time, the optimum dosage of Fe-MIL-101 was 0.5 g/L and the removal efficiency decreased with the increasing of initial tetracycline concentrations. Moreover, the trapping experiments and ESR tests indicated that O 2 -, OH and h + were the main active species in photocatalytic degradation process of tetracycline. Due to its high removal efficiency and simple synthesis, it could be used as a potential catalyst for degradation of tetracycline and other antibiotics. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Clostridium perfringens and Clostridium difficile in cooked beef sold in Côte d'Ivoire and their antimicrobial susceptibility.

    PubMed

    Kouassi, Kra Athanase; Dadie, Adjéhi Thomas; N'Guessan, Kouadio Florent; Dje, Koffi Marcellin; Loukou, Yao Guillaume

    2014-08-01

    The aim of this study was to evaluate the prevalence of Clostridium difficile and Clostridium perfringens in cooked beef sold in the streets in Côte d'Ivoire and their antimicrobial susceptibility. A total of 395 kidney and flesh samples of cooked beef were collected from vendors at Abidjan and subjected to C. difficile and C. perfringens isolation and identification by using biochemical tests, API 20A system and PCR detection. Subsequently, the antimicrobial susceptibility test was performed for confirmed isolates. Our results showed the prevalence of 12.4% for C. difficile (11.04% in kidney and 13.45% in flesh) and 5.06% for C. perfringens (2.32% in kidney and 7.17% in flesh). Metronidazole and vancomycin remained the most potent antimicrobial agents against C. difficile while metronidazole and penicillin G were the most potent agents against C. perfringens. The resistance rates to tetracycline, doxycycline, chloramphenicol and erythromycin against C. difficile and C. perfringens isolates ranged from 2.05% to 8.16% and from 20% to 50%, respectively. Among all antimicrobial agents tested against C. difficile, percentages of resistance to quinolones ciprofloxacin, norfloxacin and nalidixic acid as well as to gentamicin and cefotaxime were the highest. Eight resistant phenotypes were defined for C. difficile isolates and eleven resistant phenotypes for C. perfringens isolates. Clindamycin/gentamicin/cefotaxime/ciprofloxacin/norfloxacin/nalidixic acid resistance was the most common phenotype for C. difficile (55.10% of isolates) while norfloxacin/nalidixic acid resistance was the most common phenotype for C. perfringens (20% of isolates). Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Drug resistance in Campylobacter jejuni, C coli, and C lari isolated from humans in north west England and Wales, 1997.

    PubMed Central

    Thwaites, R T; Frost, J A

    1999-01-01

    AIMS: To test the sensitivity of strains of Campylobacter species isolated from humans in England and Wales against a range of antimicrobial agents for the purpose of monitoring therapeutic efficacy and as an epidemiological marker. METHODS: An agar dilution breakpoint technique was used to screen isolates against ampicillin, chloramphenicol, gentamicin, kanamycin, neomycin, tetracycline, nalidixic acid, ciprofloxacin, and erythromycin. Minimal inhibitory concentrations (MIC) were also determined for a sample of quinolone resistant strains. RESULTS: Approximately 50% of strains tested were resistant to at least one drug. Strains which were resistant to four or more of the drugs tested were classified as multiresistant; this occurred in 11.3% of C jejuni, 19.9% of C coli, and 63.6% of C lari. Resistance to erythromycin occurred in 1.0% of C jejuni and 12.8% of C coli. Resistance to quinolones occurred in 12% of strains, with a ciprofloxacin MIC of > 8 mg/l and a nalidixic acid MIC of > 256 mg/l; a further 4% of strains had intermediate resistance with a ciprofloxacin MIC of between 0.5 and 2 mg/l (fully sensitive strains, 0.25 mg/l or less) and a nalidixic acid MIC of between 32 and 64 mg/l (fully sensitive strains, 8 mg/l or less). CONCLUSIONS: Resistance to quinolones in campylobacters from human infection may relate to clinical overuse or use of fluoroquinolones in animal husbandry. Both veterinary and clinical use should be reconsidered and fluoroquinolone drugs used only as a treatment for serious infections requiring hospital admission. Erythromycin resistance is still rare in C jejuni but much more common in C coli. PMID:10690169

  3. Toxicological studies on pipemidic acid. V. Effect on diarthrodial joints of experimental animals.

    PubMed

    Tatsumi, H; Senda, H; Yatera, S; Takemoto, Y; Yamayoshi, M; Ohnishi, K

    1978-11-01

    Pipemidic acid (PPA) orally given in a dose of 100 mg/kg/day or more was found to cause lame gait in immature beagle dogs of about 3 months old. Their diarthrodial joints were abnormal with increased synovial fluid and blister formation under the outer layer of the articular cartilage. However, such an abnormality was not found in dogs younger than 2 weeks or older than 12 months. The blisters were formed at the joint areas bearing the body weight at a time when PPA was considered to be present there. Nalidixic and piromidic acids, structural analogues of PPA, also caused abnormality similar to PPA. The severity of the arthropathy was slight with piromidic acid as compared with PPA and nalidixic acid. The gait abnormality was almost disappeared spontaneously even if medication was continued. The incidence of the arthropathy was not or rarely observed in any young rats, rabbits and monkeys.

  4. Antimicrobial resistance pattern of Neisseria gonorrhoeae isolates from peripheral health centres and STD clinic attendees of a tertiary care centre in India.

    PubMed

    Bala, M; Ray, K; Gupta, S M

    2008-06-01

    The aim of the study was to compare the antimicrobial resistance pattern of Neisseria gonorrhoeae isolates from urban and rural peripheral health centres and from sexually transmitted disease (STD) clinic attendees. Antimicrobial susceptibility testing of 191 N. gonorrhoeae isolates (165 isolates from STD clinic attendees and 26 from peripheral health centres) was carried out in Delhi, India, using the calibrated dichotomous sensitivity technique for penicillin, tetracycline, ceftriaxone, ciprofloxacin, spectinomycin and nalidixic acid, and minimum inhibitory concentrations were determined using E-test. Penicillin-resistant, ciprofloxacin-resistant, penicillinase-producing N. gonorrhoeae and tetracycline-resistant N. gonorrhoeae strains were higher in STD clinic attendees than in peripheral health centres, probably because of less antibiotic pressure in the peripheral areas. High-level resistance to ciprofloxacin and multiresistant strains were also higher in STD clinic attendees. The present study emphasizes the importance of surveillance of antimicrobial resistance of N. gonorrhoeae in different population subgroups in order to monitor the spread of multiresistant strains and to update the national treatment recommendations.

  5. [Tetracyclines, sulfonamides and metronidazole].

    PubMed

    Pérez-Trallero, Emilio; Iglesias, Luis

    2003-11-01

    Tetracyclines form a group of natural and semisynthetic products that acts inhibiting the bacterial protein synthesis. They are bacteriostatic agents, exhibiting activity against a wide range of organisms, but they are at the present of limited use because of their acquired resistance. Doxycycline is currently the most frequently used tetracycline in human medicine and it is included in the List of Essential Medicines of the World Health Organization. Sulfonamides are synthetic, broad-spectrum bacteriostatic antibiotics. They were the first effective systemic antimicrobial agents. Their mode of action is based on the inhibition of DNA synthesis. Due to their toxicity and high adquired resistance their use is currently very low. Metronidazole is the main compound of 5-nitroimidazole family. It is a very active bactericidal antibiotic against anaerobic and some microaerophilic bacteria and it is still very useful in the treatment of bacterian and parasitic infections.

  6. Characterization of tetracycline-resistant bacteria in an urbanizing subtropical watershed.

    PubMed

    Sullivan, B A; Gentry, T; Karthikeyan, R

    2013-09-01

    The objective of this study was to determine whether varying levels of urbanization influence the dominant bacterial species of mildly resistant (0·03 mmol l(-1) tetracycline) and highly resistant (0·06 mmol l(-1) tetracycline) bacteria in sediment and water. Also, the level of urbanization was further evaluated to determine whether the diversity of tetracycline resistance genes present in the isolates and the capability of transferring their resistance were influenced. Sediment and water samples collected from five sampling sites were plated in triplicate on nutrient agar plates with a mild dose (0·03 mmol l(-1) ) and a high dose (0·06 mmol l(-1) ) of tetracycline. Five colonies from each plate plus an additional five from each triplicate group were randomly selected and isolated on nutrient agar containing 0·03 mmol l(-1) tetracycline (400 isolates). The isolates were identified by 16S rRNA gene sequencing and comparison to GenBank using blast. The isolates were also screened for 15 tetracycline resistance genes using a multiplex PCR assay and their ability to transfer resistance through conjugation experiments using a kanamycin-resistant Escherichia. coli K-12 strain labelled with a green fluorescent protein gene. Results from this study indicate that the dominant resistant organisms in this watershed are Acinetobacter spp., Chryseobacterium spp., Serratia spp., Pseudomonas spp., Aeromonas spp. and E. coli. All of these organisms are Gram negative and are closely related to pathogenic species. A majority of the isolates (66%) were capable of transferring their resistance, and there was a greater incidence of tet resistance transfer with increasing urbanization. Also, it was determined that the dominant resistance genes in the watershed are tet(W) and tet(A). Urbanization significantly affected dominant tetracycline-resistant bacteria species, but did not affect dominant resistance genes. There was correlation between increased urbanization with an

  7. Sclerotherapy with tetracycline solution for hydrocele.

    PubMed

    Hu, K N; Khan, A S; Gonder, M

    1984-12-01

    A study of sclerotherapy for hydrocele using different concentrations (10%, 5%, 2.5%) for tetracycline solution was done on 24 patients, 23 patients were cured. The effectiveness of sclerotherapy was the same for the three groups of patients with use of each different concentration of the solution. Pain was the only adverse effect. Nonspecific cellular foreign body reaction and fibrin strand proliferation were observed in the hydrocele fluid after this procedure. We consider sclerotherapy for hydrocele with tetracycline solution safe and the procedure of choice for patients in whom surgery or anesthesia is contraindicated, for patients who refuse surgery, and for economic reasons.

  8. Phenotypic and genotypic characterization of tetracycline and minocycline resistance in Clostridium perfringens

    USDA-ARS?s Scientific Manuscript database

    The aim of this study was to determine the incidence of tetracycline resistance and the prevalence of tetracycline-resistance genes in strains of Clostridium perfringens isolated from different sources between 1994 and 2005. Susceptibility to tetracycline and minocycline in C. perfringens isolates ...

  9. Sclerotherapy with tetracycline for hydroceles in renal transplant patients.

    PubMed

    Sankari, B R; Boullier, J A; Garvin, P J; Parra, R O

    1992-10-01

    A total of 17 patients with hydroceles following renal transplantation underwent sclerotherapy with tetracycline hydrochloride (10 ml. of a 5% solution of tetracycline in 1% lidocaine). A successful outcome was obtained in 15 patients (88%). Post-sclerotherapy hydrocelectomy was necessary in 2 patients (12%). No major complications (testicular loss, scrotal abscess or necrosis) occurred in any patient. Pain at injection was the only adverse effect. Tetracycline sclerotherapy for hydroceles appears to be an effective and safe procedure in the renal transplant population. We recommend this procedure as the initial treatment modality for hydroceles in patients with a renal allograft.

  10. Differential Top10 promoter regulation by six tetracycline analogues in plant cells

    NASA Technical Reports Server (NTRS)

    Love, John; Allen, George C.; Gatz, Christiane; Thompson, William F.; Brown, C. S. (Principal Investigator)

    2002-01-01

    The effects of five tetracycline analogues, anhydrotetracycline, doxycycline, minocycline, oxytetracycline, and tetracycline, on Top10 promoter activity in NT1 tobacco tissue culture cells have been analysed. The concentration that repressed Top10 promoter activity, the level of transgene repression and the kinetics of transgene de-repression were determined for each analogue, and could not be predicted from in vitro binding affinity to the tetracycline repressor or from comparison with animal cells. Doxycycline had the most potent effect on the Top10 promoter and completely inhibited transgene expression at 4 nmol l(-1). Tetracycline was the most versatile of the analogues tested; tetracycline inhibited the Top10 promoter at 10 nmol l(-1) and was easily washed out to restore Top10-driven expression in 12-24 h. A study was also made of the suitability for plant research of a novel tetracycline analogue, GR33076X. In animal cells, GR33076X de-repressed Top10 promoter activity in the presence of inhibitory concentrations of anhydrotetracycline. In NT1, it is shown that GR 33076X can antagonize repression of the Top10 promoter in the presence of tetracycline, but not of anhydrotetracycline or of doxycycline. Different tetracycline analogues can therefore be used to regulate the Top10 promoter in plant cells and this property may be exploited in planning an optimum course of transgene regulation.

  11. Differential Top10 promoter regulation by six tetracycline analogues in plant cells.

    PubMed

    Love, John; Allen, George C; Gatz, Christiane; Thompson, William F

    2002-09-01

    The effects of five tetracycline analogues, anhydrotetracycline, doxycycline, minocycline, oxytetracycline, and tetracycline, on Top10 promoter activity in NT1 tobacco tissue culture cells have been analysed. The concentration that repressed Top10 promoter activity, the level of transgene repression and the kinetics of transgene de-repression were determined for each analogue, and could not be predicted from in vitro binding affinity to the tetracycline repressor or from comparison with animal cells. Doxycycline had the most potent effect on the Top10 promoter and completely inhibited transgene expression at 4 nmol l(-1). Tetracycline was the most versatile of the analogues tested; tetracycline inhibited the Top10 promoter at 10 nmol l(-1) and was easily washed out to restore Top10-driven expression in 12-24 h. A study was also made of the suitability for plant research of a novel tetracycline analogue, GR33076X. In animal cells, GR33076X de-repressed Top10 promoter activity in the presence of inhibitory concentrations of anhydrotetracycline. In NT1, it is shown that GR 33076X can antagonize repression of the Top10 promoter in the presence of tetracycline, but not of anhydrotetracycline or of doxycycline. Different tetracycline analogues can therefore be used to regulate the Top10 promoter in plant cells and this property may be exploited in planning an optimum course of transgene regulation.

  12. Comparison of two fabricated aptasensors based on modified carbon paste/oleic acid and magnetic bar carbon paste/Fe3O4@oleic acid nanoparticle electrodes for tetracycline detection.

    PubMed

    Jahanbani, Shahriar; Benvidi, Ali

    2016-11-15

    In this research, we have improved two aptasensors based on a modified carbon paste electrode (CPE) with oleic acid (OA), and a magnetic bar carbon paste electrode (MBCPE) with Fe3O4 magnetic nanoparticles and oleic acid (OA). After the immobilization process of anti-TET at the electrode surfaces, the aptasensors were named CPE/OA/anti-TET and MBCPE/Fe3O4NPs/OA/anti-TET respectively. In this paper, the detection of tetracycline is compared using CPE/OA/anti-TET and MBCPE/Fe3O4NPs/OA/anti-TET aptasensors. These modified electrodes were characterized by infrared spectroscopy (IR), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), UV-vis spectroscopy, and voltammetric methods. The linear range and the detection limit for TET with the CPE/OA/anti-TET aptasensor were found to be 1.0×10(-12)-1.0×10(-7)M and 3.0×10(-13)M respectively by EIS method. The linear range and the detection limit for TET with the CPE/OA/anti-TET aptasensor were found to be 1.0×10(-10)-1.0×10(-7)M with a limit of detection of 2.9×10(-11)M using differential pulse voltammetry (DPV) technique. The MBCPE/Fe3O4NPs/OA/anti-TET aptasensor was used for determination of TET, and a liner range of 1.0×10(-14)-1.0×10(-6)M with a detection limit of 3.8×10(-15)M was obtained by EIS method. Also, the linear range and detection limit of 1.0×10(-12)-1.0×10(-6)M and 3.1×10(-13)M respectively, were obtained for MBCPE/Fe3O4NPs/OA/anti-TET aptasensor using DPV. The proposed aptasensors were applied for determination of tetracycline in some real samples such as drug, milk, honey and blood serum samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Detection of Tetracycline in Milk using NIR Spectroscopy and Partial Least Squares

    NASA Astrophysics Data System (ADS)

    Wu, Nan; Xu, Chenshan; Yang, Renjie; Ji, Xinning; Liu, Xinyuan; Yang, Fan; Zeng, Ming

    2018-02-01

    The feasibility of measuring tetracycline in milk was investigated by near infrared (NIR) spectroscopic technique combined with partial least squares (PLS) method. The NIR transmittance spectra of 40 pure milk samples and 40 tetracycline adulterated milk samples with different concentrations (from 0.005 to 40 mg/L) were obtained. The pure milk and tetracycline adulterated milk samples were properly assigned to the categories with 100% accuracy in the calibration set, and the rate of correct classification of 96.3% was obtained in the prediction set. For the quantitation of tetracycline in adulterated milk, the root mean squares errors for calibration and prediction models were 0.61 mg/L and 4.22 mg/L, respectively. The PLS model had good fitting effect in calibration set, however its predictive ability was limited, especially for low tetracycline concentration samples. Totally, this approach can be considered as a promising tool for discrimination of tetracycline adulterated milk, as a supplement to high performance liquid chromatography.

  14. Tetracyclines function as dual-action light-activated antibiotics.

    PubMed

    He, Ya; Huang, Ying-Ying; Xi, Liyan; Gelfand, Jeffrey A; Hamblin, Michael R

    2018-01-01

    Antimicrobial photodynamic inactivation (aPDI) employs photosensitizing dyes activated by visible light to produce reactive oxygen species. aPDI is independent of the antibiotic resistance status of the target cells, and is thought unlikely to produce resistance itself. Among many PS that have been investigated, tetracyclines occupy a unique niche. They are potentially dual-action compounds that can both kill bacteria under illumination, and prevent bacterial regrowth by inhibiting ribosomes. Tetracycline antibiotics are regarded as bacteriostatic rather than bactericidal. Doxycycline (DOTC) is excited best by UVA light (365 nm) while demeclocycline (DMCT) can be efficiently activated by blue light (415 nm) as well as UVA. Both compounds were able to eradicate Gram-positive (methicillin-resistant Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria (>6 log(10) steps of killing) at concentrations (10-50μM) and fluences (10-20J/cm2). In contrast to methylene blue, MB plus red light, tetracyclines photoinactivated bacteria in rich growth medium. When ~3 logs of bacteria were killed with DMCT/DOTC+light and the surviving cells were added to growth medium, further bacterial killing was observed, while the same experiment with MB allowed complete regrowth. MIC studies were carried out either in the dark or exposed to 0.5mW/cm2 blue light. Up to three extra steps (8-fold) increased antibiotic activity was found with light compared to dark, with MRSA and tetracycline-resistant strains of E. coli. Tetracyclines can accumulate in bacterial ribosomes, where they could be photoactivated with blue/UVA light producing microbial killing via ROS generation.

  15. Tetracycline Susceptibility in Chlamydia suis Pig Isolates.

    PubMed

    Donati, Manuela; Balboni, Andrea; Laroucau, Karine; Aaziz, Rachid; Vorimore, Fabien; Borel, Nicole; Morandi, Federico; Vecchio Nepita, Edoardo; Di Francesco, Antonietta

    2016-01-01

    The aims of the present study were to assess the prevalence of Chlamydia suis in an Italian pig herd, determine the tetracycline susceptibility of C. suis isolates, and evaluate tet(C) and tetR(C) gene expression. Conjunctival swabs from 20 pigs were tested for C. suis by real-time polymerase chain reaction, and 55% (11) were positive. C. suis was then isolated from 11 conjunctival swabs resampled from the same herd. All positive samples and isolates were positive for the tet(C) resistance gene. The in vitro susceptibility to tetracycline of the C. suis isolates showed MIC values ranging from 0.5 to 4 μg/mL. Tet(C) and tetR(C) transcripts were found in all the isolates, cultured both in the absence and presence of tetracycline. This contrasts with other Gram-negative bacteria in which both genes are repressed in the absence of the drug. Further investigation into tet gene regulation in C. suis is needed.

  16. HILIC separation mechanisms of tetracyclines on amino bonded silica column

    USDA-ARS?s Scientific Manuscript database

    Effects of mobile phase variations on the chromatographic separation on amino bonded silica column in hydrophilic interaction chromatography (HILIC) were investigated for four zwitterionic tetracyclines (TCs): oxytetracycline, doxycycline, chlortetracycline and tetracycline. A mixed-mode retention m...

  17. Prevalence and antimicrobial susceptibility of Salmonella spp. in small Indian mongooses (Herpestes auropunctatus) in Grenada, West Indies.

    PubMed

    Miller, Steven; Amadi, Victor; Stone, Diana; Johnson, Roger; Hariharan, Harry; Zieger, Ulrike

    2014-09-01

    Intestinal samples from 156 small Indian mongooses (Herpestes auropunctatus) collected island-wide in Grenada from April 2011 to March 2013 were examined for the presence of Salmonella enterica spp. Nineteen (12%) mongooses were culture-positive for S. enterica spp. of which five serotypes were identified. Salmonella javiana and S. Montevideo were the most commonly isolated serotypes. The other serotypes isolated were S. Rubislaw, S. Panama and S. Arechavaleta. All isolates were susceptible to amoxicillin-clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, imipenem and trimethoprim-sulfamethoxazole. One isolate (S. Montevideo) showed resistance to tetracycline and intermediate resistance to streptomycin. The five isolated Salmonella serotypes are potential human pathogens suggesting that the mongoose may play a role in the epidemiology of human salmonellosis in Grenada. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs

    PubMed Central

    Jardine, Jocelyn Leonie; Mavumengwana, Vuyo

    2017-01-01

    Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria, Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment. PMID:28914802

  19. Genetic and physiological characterization of ciprofloxacin resistance in Pseudomonas aeruginosa PAO.

    PubMed Central

    Robillard, N J; Scarpa, A L

    1988-01-01

    Spontaneous ciprofloxacin-resistant mutants of Pseudomonas aeruginosa PAO2 were isolated on ML agar containing 0.5 microgram of ciprofloxacin per ml (2 times the MIC). The mutants were 8- to 64-fold more resistant to ciprofloxacin and showed complete cross resistance to nalidixic acid, ofloxacin, enoxacin, and norfloxacin. Two chromosomal resistance genes, cfxA and cfxB, were mapped between eda-9001 and phe-2 and near pyrB52 distal to proC130, respectively. The cfxB mutation was identical to a nalB mutation and conferred cross resistance to novobiocin, tetracycline, carbenicillin, and chloramphenicol, suggesting that there is an effect on permeability. DNA gyrase A and B subunits were purified from strain PAO2 (wild type), PAO236 nalA2, PAO4704 cfxA2, and PAO4700 cfxA1 cfxB1. Inhibition of gyrase-mediated DNA supercoiling by ciprofloxacin or nalidixic acid was greatly reduced in preparations derived from each of the mutants. Inhibition studies on reconstituted heterologous gyrase subunits showed that decreased inhibition was dependent on the mutant gyrase A subunit. We conclude that ciprofloxacin resistance in P. aeruginosa PAO2 can occur by mutation in the nalB gene or the gene for DNA gyrase A (formerly nalA). PMID:2837141

  20. Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs.

    PubMed

    Jardine, Jocelyn Leonie; Abia, Akebe Luther King; Mavumengwana, Vuyo; Ubomba-Jaswa, Eunice

    2017-09-15

    Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria , Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment.

  1. [The adhesive properties of two bonding systems to tetracycline stained dentin].

    PubMed

    Liu, H L; Liang, K N; Cheng, L; Li, J Y; He, L B

    2016-01-01

    To investigate and compare the bonding properties of Single Bond 2 and SE Bond to tetracycline stained dentin in vitro. Ten extracted tetracycline stained human teeth and ten extracted normal human teeth were collected and the occlusal dentin surfaces of all extracted teeth were exposed. The tetracycline stained teeth and normal teeth were divided into two groups, respectively and randomly, based on the adhesives applied. Total-etch adhesive(Single Bond 2) and self-etch adhesive(SE Bond) were used. After application of the adhesives to the dentin surfaces, composite crowns were built up. After 24 h water storage, the teeth were sectioned longitudinally into sticks(0.9 mm×0.9 mm bonding area) for micro tensile testing or micro Raman spectroscopy detection. Bonding strength(μTBS) and resin conversion rate were analyzed using one-way ANOVA. The tetracycline Single Bond 2 group presented lower bonding strength[(16.17 ± 3.16) MPa] than the tetracycline SE Bond group[(25.82 ± 2.62) MPa], and also demonstrated lower bonding strength than the normal Single Bond 2 group[(29.13 ± 2.44) MPa] and the normal SE Bond group[(24.29±2.83) MPa] (P<0.05) , while there was no statistical differences among the other three groups(P>0.05). The resin conversion rate of tetracycline Single Bond 2 group[(55±6)%] was significantly lower than the tetracycline SE Bond group[(66±3)% ](P<0.05) and also lower than the normal Single Bond 2 group[(64 ± 5)%] and the normal SE Bond group[(65 ± 4)%] (P<0.05). No statistically significant differences were observed among the other three groups(P>0.05). The bonding strength of total-etch adhesive system to the tetracycline stained dentin was significantly lower than that to the normal dentin.

  2. Bioavailability of Tetracycline and Doxycycline in Fasted and Nonfasted Subjects

    PubMed Central

    Welling, Peter G.; Koch, Patricia A.; Lau, Curtis C.; Craig, William A.

    1977-01-01

    The influence of various test meals and fluid volumes on the relative bioavailability of commercial formulations of doxycycline hyclate and tetracycline hydrochloride was studied in healthy human volunteers. Serum levels of tetracycline were uniformly reduced by approximately 50% by all test meals, whereas serum levels of doxycycline were reduced by 20%. The reduction of tetracycline serum levels will likely be of clinical significance. The bioavailability of each drug was almost identical from an oral solution and from capsules in fasted subjects. The rate of doxycycline absorption was reduced when capsules were administered with a small volume of water, but the overall efficiency of absorption of both drugs was essentially independent of co-administered fluid volume. The use of 8-h serum data provides a reliable estimate of drug bioavailability for tetracycline and, to a lesser extent, for doxycycline. PMID:856000

  3. Tetracycline compounds with non-antimicrobial organ protective properties: possible mechanisms of action

    PubMed Central

    Griffin, Michael O.; Ceballos, Guillermo; Villarreal, Francisco

    2010-01-01

    Tetracyclines were developed as a result of the screening of soil samples for antibiotics. The firstt of these compounds, chlortetracycline, was introduced in 1947. Tetracyclines were found to be highly effective against various pathogens including rickettsiae, as well as both gram-positive and gram-negative bacteria, thus becoming the first class of broad spectrum antibiotics. Many other interesting properties, unrelated to their antibiotic activity, have been identified for tetracyclines which have led to widely divergent experimental and clinical uses. For example, tetracyclines are also an effective anti-malarial drug. Minocycline, which can readily cross cell membranes, is known to be a potent anti-apoptotic agent. Another tetracycline, doxycycline is known to exert anti-protease activities. Doxycycline can inhibit matrix metalloproteinases which contribute to tissue destruction activities in diseases such as periodontitis. A large body of literature has provided additional evidence for the “beneficial” actions of tetracyclines, including their ability to act as reactive oxygen species scavengers and anti-inflammatory agents. This review provides a summary of tetracycline’s multiple mechanisms of action as a means to understand their beneficial effects. PMID:20951211

  4. Prevalence, antibiogram and risk factors of thermophilic campylobacter spp. in dressed porcine carcass of Chitwan, Nepal

    PubMed Central

    2014-01-01

    Background Campylobacter is the primary cause of food borne gastroenteritis. Moreover, the emergence of multiple drug resistant campylobacters from poultry and pork has produced a potential threat to public health. Research addressing these issues is sparse in Nepal. So, this cross-sectional study aims at determining the prevalence, antibiogram and risk factors of campylobacters from dressed porcine carcass of Chitwan, Nepal. Results We collected 139 samples of dressed porcine carcass from 10 different pork shops located in Chitwan district and processed according to OIE Terrestrial Manual, 2008, chapter 2.8.10. Antibiogram of identified Campylobacter spp. was evaluated against nine commonly used antibiotics by using disc diffusion method following CLSI guidelines. The prevalence of Campylobacter spp. was 38.84% (C. coli 76% and C. jejuni 24%). There was no significant difference (p > 0.05) between the prevalence rate of male (32.4%) and female (41%) carcass. Ampicillin and erythromycin showed the highest resistance (92.59% each) followed by colistin (72.2%), tetracycline (61.1%), nalidixic acid and cotrimoxazole (44.4% each), ciprofloxacin (31.5%) and gentamicin (5.56%). Moreover, 77.8% of the isolates were resistant to more than two antimicrobials. Nalidixic acid and tetracycline showed significant difference (p < 0.05) in the resistivity pattern among different species of Campylobacters. The association between prevalence rate and regular sanitization of slaughter slab equipments was significant (p < 0.05). Similarly, prevalence rate was significantly associated (p < 0.01) with chilling and contamination of intestinal content with carcass. Conclusions The pork meat of Chitwan is highly contaminated with antibiotic-resistant Campylobacters and slaughtering practices play significant role in contamination. It is necessary to train the butchers about hygienic slaughtering practice. The consumers as well as butchers should adopt safety measures to prevent themselves

  5. [Serotype identification and antibiotic susceptibility of Shiga toxin-producing Escherichia coli in the Weishan area in Shandong Province, China].

    PubMed

    Shao, C C; Hu, B; Bi, Z W; Kou, Z Q; Fang, M; Chen, B L; Bi, Z Q

    2017-01-06

    Objective: To determine the serotypes and drug resistance profiles of Shiga toxin-producing Escherichia coli (STEC) in animal stools from the Weishan area in Shandong Province, China. To provide the basis for further study. Methods: Five hundred animal stool samples (from pigs, cattle, sheep, dogs and birds) were collected from the Weishan area and STEC strains were isolated from these samples. Strains were serotyped by a serum agglutination test, and their drug resistance profiles were determined through antimicrobial sensitivity experiments. In this study, PCR was used to detect tetracycline resistance genes ( tetA , tetB , tetC , tetD ) and beta-lactam resistance genes ( blaSHV -1, blaCTX - M , blaTEM ). Results: Sixteen strains of STEC were isolated from animal stool samples. Thirteen strains were isolated from pig stool samples, two from bovine stool samples and one from a sheep stool sample. Two of the strains were identified as E. coli O157:H7, and other 14 strains were non-O157 STEC of different serotypes. Antimicrobial sensitivity experiments showed that 15 of the strains were multidrug resistant. The rates of resistance were as follows: nalidixic acid (12/16 strains), sulfisoxazole (11/16), trimethoprim and sulphame-thoxazole (11/16), doxycycline (9/16), azithromycin (9/16), tetracycline (9/16), chloramphenicol (8/16) and streptomycin (8/16). Therefore, nalidixic acid showed the highest rate of resistance among the strains, followed by trimethoprim and sulphame-thoxazole, and sulfisoxazole. Resistance to cefepime or imipenem was not detected. In total, three types of drug resistance genes ( tetA , tetB and tetC ) were detected among the 16 strains. Conclusion: The results showed that STEC strains isolated from animals in the Weishan area were of a range of serotypes. The 16 strains of STEC isolated from animal stools in this area were resistant to a number of antibiotics, with many strains displaying multidrug resistance.

  6. Effect of Photo-Fenton Bleaching on Tetracycline-stained Dentin in vitro.

    PubMed

    Bennett, Zackary Yale; Walsh, Laurence James

    2015-02-01

    Tetracycline-stained tooth structure is difficult to bleach using nightguard tray methods. The possible benefits of in-office light-accelerated bleaching systems based on the photo-Fenton reaction are of interest as possible adjunctive treatments. This study was a proof of concept for possible benefits of this approach, using dentine slabs from human tooth roots stained in a reproducible manner with the tetracycline antibiotic demeclocycline hydrochloride. Color changes overtime in tetra-cycline stained roots from single rooted teeth treated using gel (Zoom! WhiteSpeed(®)) alone, blue LED light alone, or gel plus light in combination were tracked using standardized digital photography. Controls received no treatment. Changes in color channel data were tracked overtime, for each treatment group (N = 20 per group). Dentin was lighter after bleaching, with significant improvements in the dentin color for the blue channel (yellow shade) followed by the green channel and luminosity. The greatest changes occurred with gel activated by light (p < 0.0001), which was superior to effects seen with gel alone. Use of the light alone did not significantly alter shade. This proof of concept study demonstrates that bleaching using the photo-Fenton chemistry is capable of lightening tetracycline-stained dentine. Further investigation of the use of this method for treating tetracycline-stained teeth in clinical settings appears warranted. Because tetracycline staining may respond to bleaching treatments based on the photo-Fenton reaction, systems, such as Zoom! WhiteSpeed, may have benefits as adjuncts to home bleaching for patients with tetracycline-staining.

  7. Antimicrobial resistance of Escherichia coli isolates from broiler chickens and humans

    PubMed Central

    Miles, Tricia D; McLaughlin, Wayne; Brown, Paul D

    2006-01-01

    Background Antimicrobial usage is considered the most important factor promoting the emergence, selection and dissemination of antimicrobial-resistant microorganisms in both veterinary and human medicine. The aim of this study was to investigate the prevalence and genetic basis of tetracycline resistance in faecal Escherichia coli isolates from healthy broiler chickens and compare these data with isolates obtained from hospitalized patients in Jamaica. Results Eighty-two E. coli strains isolated from faecal samples of broiler chickens and urine and wound specimens of hospitalized patients were analyzed by agar disc diffusion to determine their susceptibility patterns to 11 antimicrobial agents. Tetracycline resistance determinants were investigated by plasmid profiling, transformations, and amplification of plasmid-borne resistance genes. Tetracycline resistance occurred at a frequency of 82.4% in avian isolates compared to 43.8% in human isolates. In addition, among avian isolates there was a trend towards higher resistance frequencies to kanamycin and nalidixic acid (p < 0.05), while a greater percentage of human isolates were resistant to chloramphenicol and gentamicin (p < 0.05). Multiple drug resistance was found in isolates from both sources and was usually associated with tetracycline resistance. Tetracycline-resistant isolates from both avian and human sources contained one or several plasmids, which were transmissible by transformation of chemically-competent E. coli. Tetracycline resistance was mediated by efflux genes tetB and/or tetD. Conclusion The present study highlights the prevalence of multiple drug resistant E. coli among healthy broiler chickens in Jamaica, possibly associated with expression of tetracycline resistance. While there did not appear to be a common source for multiple drug resistance in the strains from avian or human origin, the genes encoding resistance are similar. These results suggest that genes are disseminated in the

  8. Antibiotic resistance pattern and plasmid profiling of thermotolerant Escherichia coli isolates in drinking water.

    PubMed

    Subba, P; Joshi, D R; Bhatta, D R

    2013-01-01

    Antibiotic resistant Escherichia coli is potential source of transmission of resistance to other water borne pathogens where plasmid borne resistance is most significant. Drinking water samples were collected from different water sources: that is to say- tap, well and spring from different places of Kathmandu where E. coli and thermotolerant E. coli were isolated using membrane filtration technique. Antibiotic susceptibility was determined using a modified Kirby Bauer disc diffusion method and thermotolerant E. coli isolates from tap water were subjected for plasmid profiling. Type of water sources were not associated with the presence of coliform (P=0.155) and thermotolerant coliform (P=0.235) but the significant association was observed in thermotolerant coliform and thermotolerant E. coli for all sources tap (P=0.029), well (P=0.028), spring (P=0.05) but total coliform and E. coli association was found for well (P=0.01). All E. coli and thermotolerant E. coli isolates were susceptible to Ofloxacin, Chloramphenicol and Cotrimixazole. Resistance to Cefexime, Amikacin, Nalidixic acid, Amoxicillin, Tetracycline were 17 (54.8%), 9 (29%), 11 (35.5%), 25 (80.6%), 29 (93.5%) and 19 (57.6%), 12 (36.4%), 13 (39.4%), 31 (94%), 33 (100%) was observed in E. coli and thermotolerant E. coli respectively where 25 (75.8%) thermotolerant E. coli and 22 (70.9%) E. coli were observed with multiple drug resistance patterns. Single band of plasmid were observed in three MDRs and one non-MDR isolates and size varied from 2kb to >10kb. All Nalidixic acid resistant thermotolerant E. coli were found to harbor a plasmid. Presence of plasmid in Nalidixic acid resistant thermotolerant E. coli heightens public health issue and the need of monitoring Quinolone resistance bacteria in environment.

  9. Simultaneous degradation of tetracycline and denitrification by a novel bacterium, Klebsiella sp. SQY5.

    PubMed

    Shao, Sicheng; Hu, Yongyou; Cheng, Ce; Cheng, Jianhua; Chen, Yuancai

    2018-06-14

    Polluted waters with a high residue of tetracycline also have a high concentration of nitrate. Thus, screening for both, highly efficient tetracycline biodegradation and nitrate transformation, is a key technical strategy. In this study, a novel tetracycline degrading strain, SQY5, which was identified as Klebsiella sp., was isolated from municipal sludge. Biodegradation characteristics of tetracycline were studied under various environmental conditions; including inoculation dose (v/v), initial tetracycline concentration, temperature, and pH. Response surface methodology (RSM) analysis demonstrated that the maximum degradation ratio of tetracycline can be obtained under the condition with an initial tetracycline concentration of 61.27 mg L -1 , temperature of 34.96 °C, pH of 7.17, and inoculation dose of 29.89%. Furthermore, this was the first report on the relationship between the degradation of tetracycline and the denitrification effect, showing that a maximum tetracycline reduction rate of 0.113 mg L -1 ·h -1 and denitrification rate of 4.64 mg L -1 ·h -1 were observed within 32 h and 92 h of SQY5 inoculation, respectively. The data of this study has the potential for use in engineering processes designed for the simultaneous biological removal of nitrates while degrading antibiotics. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Biotransformation of tetracycline by a novel bacterial strain Stenotrophomonas maltophilia DT1.

    PubMed

    Leng, Yifei; Bao, Jianguo; Chang, Gaofeng; Zheng, Han; Li, Xingxing; Du, Jiangkun; Snow, Daniel; Li, Xu

    2016-11-15

    Although several abiotic processes have been reported that can transform antibiotics, little is known about whether and how microbiological processes may degrade antibiotics in the environment. This work isolated one tetracycline degrading bacterial strain, Stenotrophomonas maltophilia strain DT1, and characterized the biotransformation of tetracycline by DT1 under various environmental conditions. The biotransformation rate was the highest when the initial pH was 9 and the reaction temperature was at 30°C, and can be described using the Michaelis-Menten model under different initial tetracycline concentrations. When additional substrate was present, the substrate that caused increased biomass resulted in a decreased biotransformation rate of tetracycline. According to disk diffusion tests, the biotransformation products of tetracycline had lower antibiotic potency than the parent compound. Six possible biotransformation products were identified, and a potential biotransformation pathway was proposed that included sequential removal of N-methyl, carbonyl, and amine function groups. Results from this study can lead to better estimation of the fate and transport of antibiotics in the environment and has the potential to be utilized in designing engineering processes to remove tetracycline from water and soil. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Polymer: bioceramic composites optimization by tetracycline addition.

    PubMed

    Pataro, André L; Oliveira, Michele F; Teixeira, Karina I R; Turchetti-Maia, Regina M M; Lopes, Miriam T P; Wykrota, Francisco H L; Sinisterra, Rubén D; Cortés, Maria E

    2007-05-04

    The aim of this study was to evaluate the biocompatibility of composites of poly-lactic acid polymer (PLA) and copolymer of lactic and glycolic acid (PLGA), dispersed in a bioceramic matrix, Osteosynt (BC), to which tetracycline (TC) was added. The in vitro test used direct contact test (ASTM F-813) and elution test (USP-XXIII, ISO 10993-5), and in vivo evaluation was performed after subcutaneous implantation in outbread Swiss mice. The 0.01% (w/w) TC addition did not affect composite cytotoxicity in vitro. The macroscopic and histologic evaluation in vivo after 1, 7, 13, 21, 28 and 56 days showed an initial intense infiltrate of inflammatory cells for most of the groups. The tissue showed normal pattern after 21 days for all the groups. TC addition exhibited significantly larger reduction of inflammation signs (Mann-Whitney test, p<0.05) in the critical period of the resolution of the inflammatory process. Angiogenesis, cellular adsorption and fibrous deposit were observed on SEM evaluation. In conclusion, TC addition optimized composites polymer/bioceramic biocompatibility, contributing to anti-inflammatory response during the early phases of the wound healing process.

  12. Validation of the BetaStar® Advanced for Tetracyclines Test Kit for the Screening of Bulk Tank and Tanker Truck Milks for the Presence of Tetracycline Drug Residues.

    PubMed

    Ankrapp, David; Schaus, Benjamin; Clements, Lauren; Klein, Frank; Rice, Jennifer; Rejman, John

    2018-05-09

    A validation study was conducted for an immunochromatographic method (BetaStar ® Advanced for Tetracyclines) for detection of tetracycline antibiotic residues in raw, commingled bovine milk. The assay was demonstrated to detect tetracycline, chlortetracycline, and oxytetracycline at levels below the FDA tolerance levels but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments. Results of internal and independent laboratory dose-response studies employing spiked samples were in agreement. All three drugs at the approximate 90/95% sensitivity levels were detected in milk collected from cows that had been treated with the specific drug. Selectivity of the assay was 100%, as no false-positive results were obtained in testing 881 control milk samples. Testing the estimated 90/95 sensitivity level for tetracycline (213 ppb), chlortetracycline (272 ppb), and oxytetracycline (180 ppb) and at 1000 ppb for each antibiotic resulted in 100% positive tests for each tetracycline. Results of ruggedness experiments established the operating parameter tolerances for the test. Results of cross-reactivity testing established that the assay detects certain other tetracycline drugs but does not cross-react with any of 32 drugs belonging to seven different drug classes. Abnormally high bacterial or somatic cell counts (SCC) in raw milk produced no assay interference.

  13. 21 CFR 556.720 - Tetracycline.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... body weight per day. (b) Tolerances. Tolerances are established for the sum of tetracycline residues in... liver, and 12 ppm in fat and kidney. [63 FR 57246, Oct. 27, 1998] ...

  14. Selective Pressure Promotes Tetracycline Resistance of Chlamydia Suis in Fattening Pigs.

    PubMed

    Wanninger, Sabrina; Donati, Manuela; Di Francesco, Antonietta; Hässig, Michael; Hoffmann, Karolin; Seth-Smith, Helena M B; Marti, Hanna; Borel, Nicole

    2016-01-01

    In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level. Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene [tet(C)] by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration [MIC] < 2 μg/ml), intermediate (2 μg/ml ≤ MIC < 4 μg/ml) or resistant (MIC ≥ 4 μg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment

  15. A novel colorimetric triple-helix molecular switch aptasensor for ultrasensitive detection of tetracycline.

    PubMed

    Ramezani, Mohammad; Mohammad Danesh, Noor; Lavaee, Parirokh; Abnous, Khalil; Mohammad Taghdisi, Seyed

    2015-08-15

    Detection methods of antibiotic residues in blood serum and animal derived foods are of great interest. In this study a colorimetric aptasensor was designed for sensitive, selective and fast detection of tetracycline based on triple-helix molecular switch (THMS) and gold nanoparticles (AuNPs). As a biosensor, THMS shows distinct advantages including high stability, sensitivity and preserving the selectivity and affinity of the original aptamer. In the absence of tetracycline, THMS is stable, leading to the aggregation of AuNPs by salt and an obvious color change from red to blue. In the presence of tetracycline, aptamer binds to its target, signal transduction probe (STP) leaves the THMS and adsorbs on the surface of AuNPs. So the well-dispersed AuNPs remain stable against salt-induced aggregation with a red color. The presented aptasensor showed high selectivity toward tetracyclines with a limit of detection as low as 266 pM for tetracycline. The designed aptasensor was successfully applied to detect tetracycline in serum and milk. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Electronic-property dependent interactions between tetracycline and graphene nanomaterials in aqueous solution.

    PubMed

    He, Lin; Liu, Fei-Fei; Zhao, Mengyao; Qi, Zhen; Sun, Xuefei; Afzal, Muhammad Zaheer; Sun, Xiaomin; Li, Yanhui; Hao, Jingcheng; Wang, Shuguang

    2018-04-01

    Understanding the interactions between graphene nanomaterials (GNMs) and antibiotics in aqueous solution is critical to both the engineering applications of GNMs and the assessment of their potential impact on the fate and transport of antibiotics in the aquatic environment. In this study, adsorption of one common antibiotic, tetracycline, by graphene oxide (GO) and reduced graphene oxide (RGO) was examined with multi-walled carbon nanotubes (MWCNTs) and graphite as comparison. The results showed that the tetracycline adsorption capacity by the four selected carbonaceous materials on the unit mass basis followed an order of GO>RGO>MWCNTs>graphite. Upon normalization by surface area, graphite, RGO and MWCNTs had almost the same high tetracycline adsorption affinity while GO exhibited the lowest. We proposed π-electron-property dependent interaction mechanisms to explain the observed different adsorption behaviors. Density functional theory (DFT) calculations suggested that the oxygen-containing functional groups on GO surface reduced its π-electron-donating ability, and thus decreased the π-based interactions between tetracycline and GO surface. Comparison of adsorption efficiency at different pH indicated that electrostatic interaction also played an important role in tetracycline-GO interactions. Site energy analysis confirmed a highly heterogeneous distribution of the binding sites and strong tetracycline binding affinity of GO surface. Copyright © 2017. Published by Elsevier B.V.

  17. The impact of a freshwater fish farm on the community of tetracycline-resistant bacteria and the structure of tetracycline resistance genes in river water.

    PubMed

    Harnisz, Monika; Korzeniewska, Ewa; Gołaś, Iwona

    2015-06-01

    The aim of this study was to assess the impact of a fish farm on the structure of antibiotic resistant bacteria and antibiotic resistance genes in water of Drwęca River. Samples of upstream river waters; post-production waters and treated post-production waters from fish farm; as well as downstream river waters were monitored for tetracycline resistant bacteria, tetracycline resistant genes, basic physico-chemical parameters and tetracyclines concentration. The river waters was characterized by low levels of pollution, which was determined based on water temperature, pH and concentrations of dissolved oxygen and tetracycline antibiotics. Culture-dependent (heterotrophic plate counts, counts of bacteria resistant to oxytetracycline (OTC(R)) and doxycycline (DOX(R)), minimum inhibitory concentrations for oxytetracycline and doxycycline, multidrug resistance of OTC(R) and DOX(R), qualitative composition of OTC(R) and DOX(R), prevalence of tet genes in resistant isolates) and culture-independent surveys (quantity of tet gene copies) revealed no significant differences in the abundance of antibiotic-resistant bacteria and antibiotic resistance genes between the studied samples. The only way in which the fish farm influenced water quality in the Drwęca River was by increasing the diversity of tetracycline-resistance genes. However, it should also be noted that the bacteria of the genera Aeromonas sp. and Acinetobacter sp. were able to transfer 6 out of 13 tested tet genes into Escherichiacoli, which can promote the spread of antibiotic resistance in the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Tetracycline resistance in semi-arid agricultural soils under long-term swine effluent application.

    PubMed

    Popova, Inna E; Josue, Rosemarie D R; Deng, Shiping; Hattey, Jeffory A

    2017-05-04

    Annually, millions pounds of antibiotics are released unmetabolized into environment along with animal wastes. Accumulation of antibiotics in soils could potentially induce the persistence of antibiotic resistant bacteria. Antibiotics such as tetracyclines and tetracycline-resistant bacteria have been previously detected in fields fertilized with animal manure. However, little is known about the accumulation of tetracyclines and the development of tetracycline resistance in semi-arid soils. Here we demonstrate that continuous land application with swine effluent, containing trace amounts of chlortetracycline, does not necessarily induce tetracycline resistance in soil bacteria. Based on the testing of more than 3,000 bacteria isolated from the amended soils, we found no significant increase in the occurrence and level of chlortetracycline resistant bacteria in soils after 15 years of continuous swine effluent fertilization. To account for a possible transfer of tetracycline-resistant bacteria originated from the swine effluent to soils, we analyzed two commonly found tetracycline resistant genes, tet(O) and tet(M), in the swine effluent and fertilized soils. Both genes were present in the swine effluent, however, they were not detectable in soils applied with swine effluent. Our data demonstrate that agronomic application of manure from antibiotic treated swine effluent does not necessarily result in the development of antibiotic bacterial resistance in soils. Apparently, concentrations of chlortetracycline present in manure are not significant enough to induce the development of antibiotic bacterial resistance.

  19. Tetracycline sclerotherapy for testicular hydroceles in renal transplant recipients.

    PubMed

    Shokeir, A A; Eraky, I; Hassan, N; Wafa, E W; Mohsen, T; Ghoneim, M A

    1994-07-01

    To study the efficacy of tetracycline sclerotherapy in renal transplant recipients with symptomatic hydroceles. A total of 21 patients with symptomatic hydroceles following renal transplantation underwent aspiration of hydrocele and injection of tetracycline hydrochloride. Sclerosant solution was prepared by dissolving 1 g tetracycline hydrochloride powder in 10 mL 1% lidocaine. The amount of sclerosant used depended on the volume of the sac: 5 mL for a sac containing up to 100 mL and 2.5 mL of sclerosant was added for each increase of 100 mL in sac volume. Twelve patients (57%) required only one treatment and 9 patients (43%) had up to 3 injections. The larger the hydrocele, the more treatments were required. The resolution of hydrocele was complete in 12 patients (57%) and partial in 7 (33%) with 2 (10%) failures. Pain at injection was observed in one third of the patients. No major complications (fever, hematoma, infections, abscess, or scrotal necrosis) occurred in any patient. No changes in the structure or size of the testicles were found by ultrasound during an average follow-up period of 35 months. Tetracycline sclerotherapy is a safe, effective, and economical form of out-patient therapy that can be recommended as primary treatment for hydroceles in patients who have undergone renal transplantation.

  20. Antibiotic resistance profile of the subgingival microbiota following systemic or local tetracycline therapy.

    PubMed

    Rodrigues, Rosa Maria J; Gonçalves, Cristiane; Souto, Renata; Feres-Filho, Eduardo Jorge; Uzeda, Milton; Colombo, Ana Paula V

    2004-06-01

    Tetracyclines have been extensively used as adjunctives to conventional periodontal therapy. Emergence of resistant strains, however, has been reported. This study evaluated longitudinally the tetracycline resistance patterns of the subgingival microbiota of periodontitis subjects treated with systemic or local tetracycline therapy+scaling and root planing (SRP). Thirty chronic periodontitis patients were randomly assigned to three groups: SRP+500 mg of systemic tetracycline twice/day for 14 days; SRP alone and SRP+tetracycline fibers (Actsite) at four selected sites for 10 days. Subgingival plaque samples were obtained from four sites with probing pocket depths (PPD)> or =6 mm in each patient at baseline, 1 week, 3, 6 and 12 months post-therapy. Samples were dispersed and diluted in pre-reduced anaerobically sterilized Ringer's solution, plated on Trypticase Soy Agar (TSA)+5% blood with or without 4 microg/ml of tetracycline and incubated anaerobically for 10 days. The percentage of resistant microorganisms were determined and the isolates identified by DNA probes and the checkerboard method. Significance of differences among and within groups over time was sought using the Kruskal-Wallis and Friedman tests, respectively. The percentage of resistant microorganisms increased significantly at 1 week in the tetracycline groups, but dropped to baseline levels over time. The SRP+Actsite group presented the lowest proportions of resistant species at 6 and 12 months. No significant changes were observed in the SRP group. The predominant tetracycline-resistant species included Streptococcus spp., Veillonela parvula, Peptostreptococcus micros, Prevotella intermedia, Gemella morbillorum and Actinobacillus actinomycetemcomitans (Aa). A high percentage of sites with resistant Aa, Porphyromonas gingivalis and Tanerella forsythensis was observed in all groups at baseline. However, T. forsythensis was not detected in any group and P. gingivalis was not present in the SRP

  1. Antimicrobial resistance of Shigella spp. from humans in Shanghai, China, 2004-2011.

    PubMed

    Zhang, Jianmin; Jin, Huiming; Hu, Jiayu; Yuan, Zhengan; Shi, Weimin; Yang, Xiaowei; Xu, Xuebin; Meng, Jianghong

    2014-03-01

    A retrospective study conducted on patients with diarrhea in Shanghai, China from 2004-2011, indicated that of 77,600 samples collected, 1,635 (2.1%) tested positive for Shigella. Species isolated included S. sonnei (1,066, 65.1%), S. flexneri (569, 34.7%), and S. boydii (3, 0.2%). Most of the Shigella isolates were found to be resistant to streptomycin (98.7%), trimethoprim (98.0%), ampicillin (92.1%), and nalidixic acid (91.7%). Additionally, many isolates were resistant to tetracycline (86.9%), trimethoprim + sulfamethoxazole (80.1%), sulfisoxazole (76.8%) and gentamicin (55.5%). Approximately 80% of the isolates were resistant to at least eight antimicrobial agents, 14% to at least ten antimicrobials tested and 10 isolates to fourteen antimicrobials, including sulfonamides, fluoroquinolones, tetracyclines, aminoglycosides and β-lactamases. Importantly, co-resistance to fluoroquinolones and the third- and fourth-generation cephalosporins was also identified. The high levels of resistance to antimicrobial agents commonly used in clinical medicine presents a great challenge to treating patients with shigellosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Identification and characterization of tetracycline resistance in Lactococcus lactis isolated from Polish raw milk and fermented artisanal products.

    PubMed

    Zycka-Krzesinska, Joanna; Boguslawska, Joanna; Aleksandrzak-Piekarczyk, Tamara; Jopek, Jakub; Bardowski, Jacek K

    2015-10-15

    To assess the occurrence of antibiotic-resistant Lactic Acid Bacteria (LAB) in Polish raw milk and fermented artisanal products, a collection comprising 500 isolates from these products was screened. Among these isolates, six strains (IBB28, IBB160, IBB161, IBB224, IBB477 and IBB487) resistant to tetracycline were identified. The strains showing atypical tetracycline resistance were classified as Lactococcus lactis: three of them were identified as L. lactis subsp. cremoris (IBB224, IBB477 and IBB487) and the other three (IBB28, IBB160, IBB161) were identified as L. lactis subsp. lactis. The mechanism involving Ribosomal Protection Proteins (RPP) was identified as responsible for tetracycline resistance. Three of the tested strains (IBB28, IBB160 and IBB224) had genes encoding the TetS protein, whereas the remaining three (IBB161, IBB477 and IBB487) expressed TetM. The results also demonstrated that the genes encoding these proteins were located on genetic mobile elements. The tet(S) gene was found to be located on plasmids, whereas tet(M) was found within the Tn916 transposon. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. 21 CFR 556.720 - Tetracycline.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Tetracycline. 556.720 Section 556.720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for...

  4. Effective Degradation of Aqueous Tetracycline Using a Nano-TiO2/Carbon Electrocatalytic Membrane

    PubMed Central

    Liu, Zhimeng; Zhu, Mengfu; Wang, Zheng; Wang, Hong; Deng, Cheng; Li, Kui

    2016-01-01

    In this work, an electrocatalytic membrane was prepared to degrade aqueous tetracycline (TC) using a carbon membrane coated with nano-TiO2 via a sol-gel process. SEM, XRD, EDS, and XPS were used to characterize the composition and structure of the electrocatalytic membrane. The effect of operating conditions on the removal rate of tetracycline was investigated systematically. The results show that the chemical oxygen demand (COD) removal rate increased with increasing residence time while it decreased with increasing the initial concentration of tetracycline. Moreover, pH had little effect on the removal of tetracycline, and the electrocatalytic membrane could effectively remove tetracycline with initial concentration of 50 mg·L−1 (pH, 3.8–9.6). The 100% tetracycline and 87.8% COD removal rate could be achieved under the following operating conditions: tetracycline concentration of 50 mg·L−1, current density of 1 mA·cm−2, temperature of 25 °C, and residence time of 4.4 min. This study provides a new and feasible method for removing antibiotics in water with the synergistic effect of electrocatalytic oxidation and membrane separation. It is evident that there will be a broad market for the application of electrocatalytic membrane in the field of antibiotic wastewater treatment. PMID:28773486

  5. A Simple Surface-Enhanced Raman Spectroscopic Method for on-Site Screening of Tetracycline Residue in Whole Milk

    PubMed Central

    Dhakal, Sagar; Chao, Kuanglin; Huang, Qing; Kim, Moon; Schmidt, Walter; Qin, Jianwei; Broadhurst, C. Leigh

    2018-01-01

    Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS) method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm) and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm−1 in water-tetracycline solutions and 1322 and 1621 cm−1 (shifted from 1317 and 1632 cm−1, respectively) in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm−1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues. PMID:29389871

  6. A Simple Surface-Enhanced Raman Spectroscopic Method for on-Site Screening of Tetracycline Residue in Whole Milk.

    PubMed

    Dhakal, Sagar; Chao, Kuanglin; Huang, Qing; Kim, Moon; Schmidt, Walter; Qin, Jianwei; Broadhurst, C Leigh

    2018-02-01

    Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS) method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm) and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm -1 in water-tetracycline solutions and 1322 and 1621 cm -1 (shifted from 1317 and 1632 cm -1 , respectively) in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm -1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues.

  7. A tetracycline inducible expression vector for Corynebacterium glutamicum allowing tightly regulable gene expression.

    PubMed

    Lausberg, Frank; Chattopadhyay, Ava Rebecca; Heyer, Antonia; Eggeling, Lothar; Freudl, Roland

    2012-09-01

    Here we report on the construction of a tetracycline inducible expression vector that allows a tightly regulable gene expression in Corynebacterium glutamicum which is used in industry for production of small molecules such as amino acids. Using the green fluorescent protein (GFP) as a reporter protein we show that this vector, named pCLTON1, is characterized by tight repression under non-induced conditions as compared to a conventional IPTG inducible expression vector, and that it allows gradual GFP synthesis upon gradual increase of anhydrotetracycline addition. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Removal of tetracycline from contaminated water by Moringa oleifera seed preparations.

    PubMed

    Santos, Andréa F S; Matos, Maria; Sousa, Ângela; Costa, Cátia; Nogueira, Regina; Teixeira, José A; Paiva, Patrícia M G; Parpot, Pier; Coelho, Luana C B B; Brito, António G

    2016-01-01

    The aim of this study was to evaluate tetracycline antibiotic (TA) removal from contaminated water by Moringa oleifera seed preparations. The composition of synthetic water approximate river natural contaminated water and TA simulated its presence as an emerging pollutant. Interactions between TA and protein preparations (extract; fraction and lectin) were also evaluated. TA was determined by solid-phase extraction followed by high-performance liquid chromatography-mass spectrometry. Moringa extract and flour removed TA from water. The extract removed TA in all concentrations, and better removal (40%) was obtained with 40 mg L(-1); seed flour (particles < 5 mm), 1.25 and 2.50 g L(-1) removed 28% and 29% of tetracycline, respectively; particles > 5 mm (0.50 g L(-1)) removed 55% of antibiotic. Interactions between TA and seed preparations were assayed by haemagglutinating activity (HA). Specific HA (SHA) of extract (pH 7) was abolished with tetracycline (5 mg L(-1)); fraction (75%) and lectin HA (97%) were inhibited with TA. Extract SHA decreased by 75% at pH 8. Zeta potential (ZP) of extract 700 mg L(-1) and tetracycline 50 mg L(-1) , pH range 5-8, showed different results. Extract ZP was more negative (-10.73 to -16.00 mV) than tetracycline ZP (-0.27 to -20.15 mV); ZP difference was greater in pH 8. The focus of this study was achieved since Moringa preparations removed TA from water and compounds interacting with tetracycline involved at least lectin-binding sites. This is a natural process, which do not promote environmental damage.

  9. Facile method for the synthesis of a magnetic CNTs-C@Fe-chitosan composite and its application in tetracycline removal from aqueous solutions.

    PubMed

    Ma, Jie; Zhuang, Yuan; Yu, Fei

    2015-06-28

    A magnetic CNTs-C@Fe-chitosan composite (CNTs-C@Fe-CS) was prepared based on as-prepared carbon nanotubes (APCNTs). The metal nanoparticles in APCNTs could be utilized directly without any purification treatment, and the carbon shells provide an effective barrier against oxidation, acid dissolution, and movement of the MNPs, thus ensuring the long-term stability of CNTs-C@Fe-CS. The results showed that CNTs-C@Fe-CS contained more abundant oxygen and nitrogen containing functional groups after chitosan modification and the composite had good magnetization characteristics, even in acidic solutions. Then CNTs-C@Fe-CS was used as an adsorbent for the removal of tetracycline from aqueous solutions. Adsorption experiments indicated that CNTs-C@Fe-CS have a good adsorption capacity (qe) of tetracycline (104 mg g(-1)). The Freundlich isotherm model fitted the experimental data better than the Langmuir isotherm model. Kinetic regression results showed that the adsorption kinetics was more accurately represented by a pseudo second-order model. Intra-particle diffusion was involved in the adsorption, but it was not the only rate-controlling step. Cu(2+) and humic acid could promote the adsorption of tetracycline on CNTs-C@Fe-CS. The CNTs-C@Fe-CS adsorbents could be effectively and quickly separated by applying an external magnetic field and the adsorption capacity was still maintained at 99.3 mg g(-1) after being used 10 times. Therefore, CNTs-C@Fe-CS is a promising magnetic nanomaterial for preconcentration and separation of organic pollutants for environmental remediation.

  10. Reutilization of the expired tetracycline for lithium ion battery anode.

    PubMed

    Hou, Hongying; Dai, Zhipeng; Liu, Xianxi; Yao, Yuan; Liao, Qishu; Yu, Chengyi; Li, Dongdong

    2018-07-15

    Waste antibiotics into the natural environment are the large challenges to the environmental protection and the human health, and the unreasonable disposal of the expired antibiotics is a major pollution source. Herein, to achieve the innocent treatment and the resource recovery, the expired tetracycline was tried to be reutilized as the electrode active material in lithium ion battery (LIB) for the first time. The micro-structure and element component of the expired tetracycline were characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). Furthermore, the corresponding electrochemical performances were also investigated by galvanostatic charge/discharge and cyclic voltammetry (CV). To be satisfactory, the expired-tetracycline-based electrode delivered the initial specific discharge capacity of 371.6mAh/g and the reversible specific capacity of 304.1mAh/g after 200cycles. The decent results will not only offer an effective strategy to recycle the expired tetracycline, but also shed a new light on the cyclic economy and the sustainable development. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Comparison of polidocanol and tetracycline in the sclerotherapy of testicular hydrocele and epididymal cyst.

    PubMed

    Daehlin, L; Tønder, B; Kapstad, L

    1997-09-01

    To compare the effects and side-effects of polidocanol and tetracycline when used as sclerosants for testicular hydrocele and epididymal cyst. Forty-five men (median age 67 years, range 42-81) with 46 hydroceles or epididymal cysts were assessed. After puncture and aspiration, the empty sac was instilled with either polidocanol or tetracycline, assigned randomly. Patients recorded any treatment-associated pain on a visual analogue scale. At 9 months of follow-up, nine of 17 men were cured after sclerotherapy with polidocanol compared with 17 of 20 men treated with tetracycline (P < 0.05). Tetracycline produced some pain for 3 days after treatment while polidocanol therapy was almost pain-free. Re-instillation should be considered for recurrences. At the follow-up after 35 months, 16 of 18 men treated with polidocanol and 20 of 22 men treated with tetracycline were satisfied with the outcome. Both polidocanol and tetracycline are useful sclerosants for treating testicular hydrocele and epididymal cyst. We prefer polidocanol as a first choice in older patients because there were few short-term side-effects.

  12. Antimicrobial resistence of Shigella species isolated during 2004 and 2005 from selected sites in Zimbabwe.

    PubMed

    Ndlovu, N; Tarupiwa, A; Mudzori, J T

    2006-01-01

    To determine the predominant serotype and antibiotic sensitivity pattern of Shigella isolates during 2004 and 2005 in Zimbabwe. Cross sectional study. National Microbiology Reference Laboratory (NMRL), Harare, Zimbabwe. 259 clinical isolates of Shigella species isolated during 2004 and 2005 in Zimbabwe were studied. These samples had been referred to the NMRL for further testing. Serotype and antibiotic sensitivity pattern of Shigella species. Of the 259 clinical isolates of Shigella tested the following species were serotyped; 141 (54.4%) were S. flexneri; 70 (27%) S. sonnei; 38 (14.7%) S. dysenteriae and 10 (3.9%) S. boydii. About 4% of all Shigella isolates tested showed full sensitivity to commonly used antibiotics, 20.8% were resistant to one antibiotic only while 75.3% were resistant to at least two antibiotics. The most common resistance among Shigella species was to cotrimoxazole (89%), tetracycline (73%), ampicillin (49%) and chloramphenicol (41%). High susceptibility among Shigella species was observed to nalidixic acid (86%), ciprofloxacin (99%) and ceftazidine (99%). There was a low drug resistance of Shigella species to nalidixic acid, a drug of choice in Zimbabwe, except among Shigella dysenteriae type 1 strains. Continuous monitoring of the susceptibility patterns of Shigella species is important in order to detect the emergence of drug resistance and to update guidelines for antibiotic treatment in shigellosis.

  13. Determination of integron frequency by a polymerase chain reaction-restriction fragment length polymorphism method in multidrug-resistant Escherichia coli, which causes urinary tract infections.

    PubMed

    Fallah, Fatemeh; Karimi, Abdollah; Goudarzi, Mehdi; Shiva, Farideh; Navidinia, Masoumeh; Jahromi, Mana Hadipour; Sajadi Nia, Raheleh Sadat

    2012-12-01

    The purpose of this study was to determine the presence of integrons in Escherichia coli, which cause urinary tract infections, and to define the association between integrons and antimicrobial susceptibility. Susceptibility of 200 isolates from urine samples of patients suffering from urinary tract infections to 13 antibiotics was determined by the Kirby-Bauer disk diffusion method. The existence of class1 and 2 integrons in resistant isolates was assessed by polymerase chain reaction-restriction fragment length polymorphism and sequencing. Antibiotic resistance patterns were observed as follows: amoxicillin 78%, tetracycline 76.1%, co-trimoxazole 67.7%, cephalotin 60%, nalidixic acid 57.4%, chloramphenicol 49%, gentamicin 46.4%, ceftazidim 38.1%, ciprofloxacin 36.2%, nitrofurantoin 33.5%, amikacin 32.1%, norfloxacin 36.1%, and imipenem 27.1%. Of 200 isolates, 155 (77.5%) were multidrug resistant (MDR). The existence of integrons was confirmed in 50.3% of isolates. Three class 1 integron types, aadA2 being the most frequently found, and four class 2 integron types are described. Significant association between resistance to gentamicin, co-trimoxazole, cephalotin, ceftazidim, imipenem, chloramphenicol, and nalidixic acid with the existence of integrons was observed. Multidrug resistance suggests that the strategy for treatment of patients with E.coli infections needs to be revised. Furthermore, it was shown that integrons may be partly responsible for multidrug resistance. Imipenem and norfloxacin were the most effective antibiotics against isolates.

  14. Interaction of tetracycline with RNA: photoincorporation into ribosomal RNA of Escherichia coli.

    PubMed Central

    Oehler, R; Polacek, N; Steiner, G; Barta, A

    1997-01-01

    Photolysis of [3H]tetracycline in the presence of Escherichia coli ribosomes results in an approximately 1:1 ratio of labelling ribosomal proteins and RNAs. In this work we characterize crosslinks to both 16S and 23S RNAs. Previously, the main target of photoincorporation of [3H]tetracycline into ribosomal proteins was shown to be S7, which is also part of the one strong binding site of tetracycline on the 30S subunit. The crosslinks on 23S RNA map exclusively to the central loop of domain V (G2505, G2576 and G2608) which is part of the peptidyl transferase region. However, experiments performed with chimeric ribosomal subunits demonstrate that peptidyltransferase activity is not affected by tetracycline crosslinked solely to the 50S subunits. Three different positions are labelled on the 16S RNA, G693, G1300 and G1338. The positions of these crosslinked nucleotides correlate well with footprints on the 16S RNA produced either by tRNA or the protein S7. This suggests that the nucleotides are labelled by tetracycline bound to the strong binding site on the 30S subunit. In addition, our results demonstrate that the well known inhibition of tRNA binding to the A-site is solely due to tetracycline crosslinked to 30S subunits and furthermore suggest that interactions of the antibiotic with 16S RNA might be involved in its mode of action. PMID:9092632

  15. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles.

    PubMed

    Shen, Li; Chen, Jing; Li, Na; He, Pingli; Li, Zhen

    2014-08-11

    A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV-vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL(-1) can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Treatment of tetracycline antibiotics by laccase in the presence of 1-hydroxybenzotriazole.

    PubMed

    Suda, Tomoyo; Hata, Takayuki; Kawai, Shingo; Okamura, Hideo; Nishida, Tomoaki

    2012-01-01

    Tetracycline antibiotics are widely used in human and veterinary medicine; however, residual amounts of these antibiotics in the environment are of concern since they could contribute to selection of resistant bacteria. In this study, tetracycline (TC), chlortetracycline (CTC), doxycycline (DC) and oxytetracycline (OTC) were treated with laccase from the white rot fungus Trametes versicolor in the presence of the redox mediator 1-hydroxybenzotriazole (HBT). High performance liquid chromatography demonstrated that DC and CTC were completely eliminated after 15 min, while TC and CTC were eliminated after 1 h. This system also resulted in a complete loss of inhibition of growth of Escherichia coli and Bacillus subtilis and the green alga Pseudokirchneriella subcapitata with decreasing tetracycline antibiotic concentration. These results suggest that the laccase-HBT system is effective in eliminating tetracycline antibiotics and removing their ecotoxicity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Antimicrobial resistance among Salmonella isolates from hospitals in Rome.

    PubMed Central

    Falbo, V.; Caprioli, A.; Mondello, F.; Cacace, M. L.; Luzi, S.; Greco, D.

    1982-01-01

    The susceptibility to antimicrobial agents of 569 salmonella isolated collected in 1977-8 from patients in hospitals in Rome was tested. Fifty-nine per cent of all isolates were resistant to one or more antimicrobials. Resistance was most common to sulphathiazole, tetracycline, streptomycin, whereas colistin, gentamicin, tobramycin, trimethoprim-sulphamethoxazole and nalidixic acid were the most active in vitro. Multiple resistance was most frequently found in strains of Salmonella wien and S. typhimurium (94% and 38% respectively). A significant change in the resistance pattern of S. wien was observed between 1977 and 1978, with a significant increase of susceptibility to some antimicrobials in 1978. Twenty-one R-plasmids transmissible to E. coli K12 were derived from 46 resistant strains of S. typhimurum. PMID:7061839

  18. Management of bacteriuria in pregnancy.

    PubMed

    Pedler, S J; Bint, A J

    1987-04-01

    Bacteriuria of pregnancy is a common condition which, although usually asymptomatic, may give rise to potentially serious sequelae. All pregnant women should therefore be screened for the presence of bacteriuria, which if detected should be treated with an antimicrobial agent believed to be safe for use in pregnancy. Appropriate antimicrobial drugs include penicillins, cephalosporins and nitrofurantoin. Nalidixic acid, aminoglycosides and sulphonamides may be used under certain circumstances and with some precautions. Tetracyclines, trimethoprim and co-trimoxazole (trimethoprim-sulphamethoxazole) should be avoided. There is some evidence that short-course therapy in pregnant women is less effective than longer courses, and we continue to recommend a 7-day course. Follow-up after completing a treatment course is an essential part of managing bacteriuria of pregnancy.

  19. Changing patient population in Dhaka Hospital and Matlab Hospital of icddr,b.

    PubMed

    Das, S K; Rahman, A; Chisti, M J; Ahmed, S; Malek, M A; Salam, M A; Bardhan, P K; Faruque, A S G

    2014-02-01

    The Diarrhoeal Disease Surveillance System of icddr,b noted increasing number of patients ≥60 years at urban Dhaka and rural Matlab from 2001 to 2012. Shigella and Vibrio cholerae were more frequently isolated from elderly people than children under 5 years and adults aged 5-59 in both areas. The resistance observed to various drugs of Shigella in Dhaka and Matlab was trimethoprim-sulphamethoxazole (72-63%), ampicillin (43-55%), nalidixic acid (58-61%), mecillinam (12-9%), azithromycin (13-0%), ciprofloxacin (11-13%) and ceftriaxone (11-0%). Vibrio cholerae isolated in Dhaka and Matlab was resistant to trimethoprim-sulphamethoxazole (98-94%), furazolidone (100%), erythromycin (71-53%), tetracycline (46-44%), ciprofloxacin (3-10%) and azithromycin (3-0%). © 2013 John Wiley & Sons Ltd.

  20. Development and optimization of a naphthoic acid-based ionic liquid as a "non-organic solvent microextraction" for the determination of tetracycline antibiotics in milk and chicken eggs.

    PubMed

    Gao, Jiajia; Wang, Hui; Qu, Jingang; Wang, Huili; Wang, Xuedong

    2017-01-15

    In traditional ionic liquids (ILs)-based microextraction, ILs are often used as extraction and dispersive solvents; however, their functional effects are not fully utilized. Herein, we developed a novel ionic liquid 1-butyl-3-methylimidazolium naphthoic acid salt ([C4MIM][NPA]) with strong acidity. It was used as a mixed dispersive solvent with conventional [C2MIM][BF4] in "functionalized ionic liquid-based non-organic solvent microextraction (FIL-NOSM)" for determination of tetracycline antibiotics (TCs) in milk and eggs. Utilization of [C4MIM][NPA] in FIL-NOSM method increased extraction recoveries (ERs) of TCs by more than 20% and eliminated the pH adjustment step because of its strong acidity. Under optimized conditions based on central composite design, the ERs of four TCs were 94.1-102.1%, and the limitsofdetection were 0.08-1.12μgkg(-1) in milk and egg samples. This proposed method provides high extraction efficiency, less pretreatment time and requires non-organic solvents for determination of trace TC concentrations in complex animal-based food matrices. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Tetracyclines in Food and Feedingstuffs: From Regulation to Analytical Methods, Bacterial Resistance, and Environmental and Health Implications

    PubMed Central

    Granados-Chinchilla, Fabio

    2017-01-01

    Antibiotics are widely used as growth promoters in animal husbandry; among them, the tetracyclines are a chemical group of relevance, due to their wide use in agriculture, surpassing in quantities applied almost every other antibiotic family. Seeing the considerable amounts of tetracyclines used worldwide, monitoring of these antibiotics is paramount. Advances must be made in the analysis of antibiotics to assess correct usage and dosage of tetracyclines in food and feedstuffs and possible residues in pertinent environmental samples. The tetracyclines are still considered a clinically relevant group of antibiotics, though dissemination of tolerance and resistance determinants have limited their use. This review focuses on four different aspects: (i) tetracyclines, usage, dosages, and regulatory issues that govern their food-related application, with particular attention to the prohibitions and restrictions that several countries have enforced in recent years by agencies from both the United States and the European Union, (ii) analytical methods for tetracyclines, determination, and residues thereof in feedstuffs and related matrices with an emphasis on the most relevant and novel techniques, including both screening and confirmatory methods, (iii) tetracycline resistance and tetracycline-resistant bacteria in feedstuff, and (iv) environmental and health risks accompanying the use of tetracyclines in animal nutrition. In the last two cases, we discuss the more relevant undesirable effects that tetracyclines exert over bacterial communities and nontarget species including unwanted effects in farmers. PMID:28168081

  2. Treatment of hydrocele: randomised prospective study of simple aspiration and sclerotherapy with tetracycline.

    PubMed

    Breda, G; Giunta, A; Gherardi, L; Xausa, D; Silvestre, P; Tamai, A

    1992-07-01

    Following reports in the literature on the efficacy of tetracycline sclerotherapy in the treatment of hydroceles, we carried out a randomised prospective study of 45 patients (50 hydroceles), comparing simple evacuation with tetracycline sclerotherapy. The results revealed no statistically significant difference in the percentage of success between the 2 groups, but complications were more common in the patients treated with tetracycline. The good results reported by other authors in non-randomised studies are, therefore, not confirmed.

  3. Meta-analysis: is combination of tetracycline and amoxicillin suitable for Helicobacter pylori infection?

    PubMed

    Lv, Zhi-Fa; Wang, Fu-Cai; Zheng, Hui-Lie; Wang, Ben; Xie, Yong; Zhou, Xiao-Jiang; Lv, Nong-Hua

    2015-02-28

    To access the efficacy of combination with amoxicillin and tetracycline for eradication of Helicobacter pylori (H. pylori), thus providing clinical practice guidelines. PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Science Citation Index, China National Knowledge Infrastructure, Wanfang, and Chinese Biomedical Literature databases and abstract books of major European, American, and Asian gastroenterological meetings were searched. All clinical trials that examined the efficacy of H. pylori eradication therapies and included both tetracycline and amoxicillin in one study arm were selected for this systematic review and meta-analysis. Statistical analysis was performed with Comprehensive Meta-Analysis Software (Version 2). Subgroup, meta-regression, and sensitivity analyses were also carried out. Thirty-three studies met the inclusion criteria. The pooled odds ratio (OR) was 0.90 (95%CI: 0.42-1.78) for quadruple therapy with amoxicillin and tetracycline vs other quadruple regimens, and total eradication rates were 78.1% by intention-to-treat (ITT) and 84.5% by per-protocol (PP) analyses in the experimental groups. The pooled eradication rates of 14-d quadruple regimens with a combination of amoxicillin and tetracycline were 82.3% by ITT and 89.0% by PP, and those of 10-d regimens were 84.6% by ITT and 93.7% by PP. The OR by ITT were 1.21 (95%CI: 0.64-2.28) for triple regimens with amoxicillin and tetracycline vs other regimens and 1.81 (95%CI: 1.37-2.41) for sequential treatment with amoxicillin and tetracycline vs other regimens, respectively. The effectiveness of regimens employing amoxicillin and tetracycline for H. pylori eradication may be not inferior to other regimens, but further study should be necessary.

  4. 21 CFR 520.2345h - Tetracycline hydrochloride, sodium novobiocin, and prednisolone tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... prednisolone tablets. 520.2345h Section 520.2345h Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... ANIMAL DRUGS § 520.2345h Tetracycline hydrochloride, sodium novobiocin, and prednisolone tablets. (a) Specifications. Each tablet contains the equivalent of 60 milligrams of tetracycline hydrochloride, 60 milligrams...

  5. Prevalence and antibiotic resistance of Salmonella spp. in meat products, meat preparations and minced meat

    NASA Astrophysics Data System (ADS)

    Rašeta, M.; Mrdović, B.; Janković, V.; Bečkei, Z.; Lakićević, B.; Vidanović, D.; Polaček, V.

    2017-09-01

    This study aimed to determine Salmonella spp. prevalence in meat products, meat preparations and minced meat. Over a period of three years, a total of 300 samples were taken (100 RTE meat products, 100 meat preparations and 100 minced meat) and examined for the presence of Salmonella spp. Sampling was carried out at the warehouses of the food manufacturers. Salmonella spp. were not detected in RTE meat products, while 7% of semi-finished meat products (fresh sausages, grill meat formed and unformed) contained Salmonella, as did 18% of minced meats (minced pork II category, minced beef II category, mixed minced meat). The 25 Salmonella isolates obtained were examined for antibiotic resistance by the disk diffusion test, according to the NCCLS and CLSI guidelines. Isolates showed resistance to ampicillin and nalidixic acid (80%), tetracycline (72%), cefotaxime/clavulanic acid (48%), but not to gentamicin (8%) or trimethoprim/sulfamethoxazole (0%).

  6. A new tetracycline efflux gene, tet(40), is located in tandem with tet(O/32/O) in a human gut firmicute bacterium and in metagenomic library clones.

    PubMed

    Kazimierczak, Katarzyna A; Rincon, Marco T; Patterson, Andrea J; Martin, Jennifer C; Young, Pauline; Flint, Harry J; Scott, Karen P

    2008-11-01

    The bacterium Clostridium saccharolyticum K10, isolated from a fecal sample obtained from a healthy donor who had received long-term tetracycline therapy, was found to carry three tetracycline resistance genes: tet(W) and the mosaic tet(O/32/O), both conferring ribosome protection-type resistance, and a novel, closely linked efflux-type resistance gene designated tet(40). tet(40) encodes a predicted membrane-associated protein with 42% amino acid identity to tetA(P). Tetracycline did not accumulate in Escherichia coli cells expressing the Tet(40) efflux protein, and resistance to tetracycline was reduced when cells were incubated with an efflux pump inhibitor. E. coli cells carrying tet(40) had a 50% inhibitory concentration of tetracycline of 60 microg/ml. Analysis of a transconjugant from a mating between donor strain C. saccharolyticum K10 and the recipient human gut commensal bacterium Roseburia inulinivorans suggested that tet(O/32/O) and tet(40) were cotransferred on a mobile element. Sequence analysis of a 37-kb insert identified on the basis of tetracycline resistance from a metagenomic fosmid library again revealed a tandem arrangement of tet(O/32/O) and tet(40), flanked by regions with homology to parts of the VanG operon previously identified in Enterococcus faecalis. At least 10 of the metagenomic inserts that carried tet(O/32/O) also carried tet(40), suggesting that tet(40), although previously undetected, may be an abundant efflux gene.

  7. Antibiotics in the human food chain: establishing no effect levels of tetracycline, neomycin, and erythromycin using a chemostat model of the human colonic microflora.

    PubMed

    Carman, Robert J; Simon, Mary Alice; Petzold, H Earl; Wimmer, Robert F; Batra, Monica R; Fernández, A Haydée; Miller, Margaret A; Bartholomew, Mary

    2005-11-01

    A chemostat model of the healthy human large bowel ecosystem was used to establish no effect levels for tetracycline, neomycin, and erythromycin. For each compound, the equivalent to four oral doses (0, 1.5, 15, and 150 mg/60 kg person/d) was studied. Concentrations of the test compounds in the chemostat medium were intended to simulate fecal levels that might be expected following consumption of food containing antibiotic residue and were based on published oral doses and fecal levels. We monitored the following parameters: short chain fatty acids, bile acids, sulfate reduction, azoreductase and nitroreductase activities, beta-glucosidase and beta-glucuronidase activities, a range of bacterial counts and, lastly, the susceptibility among sentinel bacteria to each test compound. Neomycin and erythromycin reduced bile acid metabolism. Neomycin elevated propionate levels and caused a marginal diminution in azoreductase activity. Based on our results, the no observed effect level (NOEL) of both tetracycline and erythromycin was 15 mg/60 kg person/d. The NOEL for neomycin was 1.5 mg/60 kg person/d.

  8. A combination of ellagic acid and tetracycline inhibits biofilm formation and the associated virulence of Propionibacterium acnes in vitro and in vivo.

    PubMed

    Sivasankar, Chandran; Maruthupandiyan, Shanmugam; Balamurugan, Krishnaswamy; James, Prabhanand Bhaskar; Krishnan, Venkat; Pandian, Shunmugiah Karutha

    2016-01-01

    Propionibacterium acnes is an opportunistic pathogen which has become notorious owing to its ability to form a recalcitrant biofilm and to develop drug resistance. The current study aimed to develop anti-biofilm treatments against clinical isolates of P. acnes under in vitro and in vivo conditions. A combination of ellagic acid and tetracycline (ETC; 250 μg ml(-1) + 0.312 μg ml(-1)) was determined to effectively inhibit biofilm formation by P. acnes (80-91%) without affecting its growth, therefore potentially limiting the possibility of the bacterium attaining resistance. In addition, ETC reduced the production of extracellular polymeric substances (EPS) (20-26%), thereby making P. acnes more susceptible to the human immune system and antibiotics. The anti-biofilm potential of ETC was further substantiated under in vivo conditions using Caenorhabditis elegans. This study reports a novel anti-biofilm combination that could be developed as an ideal therapeutic agent with broad cosmeceutical and pharmaceutical applicability in the era of antibiotic resistance.

  9. Aspiration and tetracycline sclerotherapy of hydrocele.

    PubMed

    Fuse, H; Nishikawa, Y; Shimazaki, J; Katayama, T

    1991-01-01

    Seventeen patients with hydrocele of the testis were treated by aspiration of fluid and substitution with tetracycline supplemented with 1% lidocaine. In 15 patients (88%) symptoms disappeared by sclerotherapy. After sclerotherapy scrotal ultrasonography was useful to diagnose either relapse or thickened tunica vaginalis. No side effect was noticed.

  10. Background Nutrients Affect the Biotransformation of Tetracycline by Stenotrophomonas maltophilia as Revealed by Genomics and Proteomics.

    PubMed

    Leng, Yifei; Bao, Jianguo; Song, Dandan; Li, Jing; Ye, Mao; Li, Xu

    2017-09-19

    Certain bacteria are resistant to antibiotics and can even transform antibiotics in the environment. It is unclear how the molecular mechanisms underlying the resistance and biotransformation processes vary under different environmental conditions. The objective of this study is to investigate the molecular mechanisms of tetracycline resistance and biotransformation by Stenotrophomonas maltophilia strain DT1 under various background nutrient conditions. Strain DT1 was exposed to tetracycline for 7 days with four background nutrient conditions: no background (NB), peptone (P), peptone plus citrate (PC), and peptone plus glucose (PG). The biotransformation rate follows the order of PC > P > PG > NB ≈ 0. Genomic analysis showed that strain DT1 contained tet(X1), a gene encoding an FAD-binding monooxygenase, and eight peroxidase genes that could be relevant to tetracycline biotransformation. Quantitative proteomic analyses revealed that nodulation protein transported tetracycline outside of cells; hypoxanthine-guanine phosphoribosyltransferase facilitated the activation of the ribosomal protection proteins to prevent the binding of tetracycline to the ribosome and superoxide dismutase and peroxiredoxin-modified tetracycline molecules. Comparing different nutrient conditions showed that the biotransformation rates of tetracycline were positively correlated with the expression levels of superoxide dismutase.

  11. Effect of Tetracycline Antibiotics on Performance and Microbial Community of Algal Photo-Bioreactor.

    PubMed

    Taşkan, Ergin

    2016-07-01

    Tetracycline antibiotics have been increasingly used in medical applications and have been found in wastewater treatment plants as a result of human and industrial activities. This study investigates the combined effects of tetracycline antibiotics on the performance of an algal photo-bioreactor operated under different antibiotic concentrations in the ranges of 0.25 to 30 mg/L and considers the inhibition of algal growth, carbon and nutrient removal rates, and eukaryotic and cyanobacterial algal community changes. The results indicated that increases in the concentration of tetracycline mixtures have adverse effects on the algal community and the performance of a photo-bioreactor, and the eukaryotic algae species were more sensitive to tetracycline antibiotics than were the cyanobacterial species. Cultivation tests showed that approximately 94 % growth inhibition of mixed algae occurred at 30 mg/L.

  12. Diversity of the Tetracycline Mobilome within a Chinese Pig Manure Sample

    PubMed Central

    Leclercq, Sébastien Olivier; Wang, Chao; Zhu, Yaxin; Wu, Hai; Du, Xiaochen; Liu, Zhipei

    2016-01-01

    ABSTRACT Tetracycline antibiotics are widely used in livestock, and tetracycline resistance genes (TRG) are frequently reported in the manure of farmed animals. However, the diversity of TRG-carrying transposons in manure has still been rarely investigated. Using a culture-free functional metagenomic procedure, combined with large-insert library construction and sequencing, bioinformatic analyses, and functional experiments, we identified 17 distinct TRGs in a single pig manure sample, including two new tet genes: tet(59), encoding a tetracycline efflux pump, and tet(W/N/W), encoding mosaic ribosomal protection. Our study also revealed six new TRG-carrying putative nonconjugative transposons: Tn5706-like transposon Tn6298, IS200/605-related transposon Tn6303, Tn3 family transposon Tn6299, and three ISCR2-related transposons, Tn62300, Tn62301, and Tn62302. IMPORTANCE Fertilization of agricultural fields with animal manure is believed to play a major role in antibiotic resistance dissemination in the environment. There is growing concern for the possible spread of antibiotic resistance from the environment to humans since genetic resistance determinants may be located in transposons and other mobile genetic elements potentially transferable to pathogens. Among the various antibiotic resistance genes found in manure, tetracycline resistance genes (TRGs) are some of the most common. The present study provides a detailed snapshot of the tetracycline mobilome in a single pig manure sample, revealing an unappreciated diversity of TRGs and potential TRG mobility vectors. Our precise identification of the TRG-carrying units will enable us to investigate in more details their mobility effectiveness. PMID:27565618

  13. Diversity of the Tetracycline Mobilome within a Chinese Pig Manure Sample.

    PubMed

    Leclercq, Sébastien Olivier; Wang, Chao; Zhu, Yaxin; Wu, Hai; Du, Xiaochen; Liu, Zhipei; Feng, Jie

    2016-11-01

    Tetracycline antibiotics are widely used in livestock, and tetracycline resistance genes (TRG) are frequently reported in the manure of farmed animals. However, the diversity of TRG-carrying transposons in manure has still been rarely investigated. Using a culture-free functional metagenomic procedure, combined with large-insert library construction and sequencing, bioinformatic analyses, and functional experiments, we identified 17 distinct TRGs in a single pig manure sample, including two new tet genes: tet(59), encoding a tetracycline efflux pump, and tet(W/N/W), encoding mosaic ribosomal protection. Our study also revealed six new TRG-carrying putative nonconjugative transposons: Tn5706-like transposon Tn6298, IS200/605-related transposon Tn6303, Tn3 family transposon Tn6299, and three ISCR2-related transposons, Tn62300, Tn62301, and Tn62302 IMPORTANCE: Fertilization of agricultural fields with animal manure is believed to play a major role in antibiotic resistance dissemination in the environment. There is growing concern for the possible spread of antibiotic resistance from the environment to humans since genetic resistance determinants may be located in transposons and other mobile genetic elements potentially transferable to pathogens. Among the various antibiotic resistance genes found in manure, tetracycline resistance genes (TRGs) are some of the most common. The present study provides a detailed snapshot of the tetracycline mobilome in a single pig manure sample, revealing an unappreciated diversity of TRGs and potential TRG mobility vectors. Our precise identification of the TRG-carrying units will enable us to investigate in more details their mobility effectiveness. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  14. Biosolid-borne tetracyclines and sulfonamides in plants.

    PubMed

    Mathews, Shiny; Reinhold, Dawn

    2013-07-01

    Tetracyclines and sulfonamides used in human and animal medicine are released to terrestrial ecosystems from wastewater treatment plants or by direct manure application. The interactions between plants and these antibiotics are numerous and complex, including uptake and accumulation, phytometabolism, toxicity responses, and degradation in the rhizosphere. Uptake and accumulation of antibiotics have been studied in plants such as wheat, maize, potato, vegetables, and ornamentals. Once accumulated in plant tissue, organic contaminants can be metabolized through a sequential process of transformation, conjugation through glycosylation and glutathione pathways, and ultimately sequestration into plant tissue. While studies have yet to fully elucidate the phytometabolism of tetracyclines and sulfonamides, an in-depth review of plant and mammalian studies suggest multiple potential transformation and conjugation pathways for tetracyclines and sulfonamides. The presence of contaminants in the vicinity or within the plants can elicit stress responses and defense mechanisms that can help tolerate the negative effects of contaminants. Antibiotics can change microbial communities and enzyme activity in the rhizosphere, potentially inducing microbial antibiotic resistance. On the other hand, the interaction of microbes and root exudates on pharmaceuticals in the rhizosphere can result in degradation of the parent molecule to less toxic compounds. To fully characterize the environmental impacts of increased antibiotic use in human medicine and animal production, further research is essential to understand the effects of different antibiotics on plant physiology and productivity, uptake, translocation, and phytometabolism of antibiotics, and the role of antibiotics in the rhizosphere.

  15. Widespread distribution of a tet W determinant among tetracycline-resistant isolates of the animal pathogen Arcanobacterium pyogenes.

    PubMed

    Billington, Stephen J; Songer, J Glenn; Jost, B Helen

    2002-05-01

    Tetracycline resistance is common among isolates of the animal commensal and opportunistic pathogen Arcanobacterium pyogenes. The tetracycline resistance determinant cloned from two bovine isolates of A. pyogenes was highly similar at the DNA level (92% identity) to the tet(W) gene, encoding a ribosomal protection tetracycline resistance protein, from the rumen bacterium Butyrivibrio fibrisolvens. The tet(W) gene was found in all 20 tetracycline-resistant isolates tested, indicating that it is a widely distributed determinant of tetracycline resistance in this organism. In 25% of tetracycline-resistant isolates, the tet(W) gene was associated with a mob gene, encoding a functional mobilization protein, and an origin of transfer, suggesting that the determinant may be transferable to other bacteria. In fact, low-frequency transfer of tet(W) was detected from mob+ A. pyogenes isolates to a tetracycline-sensitive A. pyogenes recipient. The mobile nature of this determinant and the presence of A. pyogenes in the gastrointestinal tract of cattle and pigs suggest that A. pyogenes may have inherited this determinant within the gastrointestinal tracts of these animals.

  16. Tetracycline rapidly reaches all the constituent cells of uropathogenic Escherichia coli biofilms

    NASA Technical Reports Server (NTRS)

    Stone, G.; Wood, P.; Dixon, L.; Keyhan, M.; Matin, A.; Demain, A. L. (Principal Investigator)

    2002-01-01

    We have developed a method for visualizing Escherichia coli cells that are exposed to tetracycline in a biofilm, based on a previous report that liposomes containing the E. coli TetR(B) protein fluoresce when exposed to this antibiotic. By our method, cells devoid of TetR(B) also exhibited tetracycline-dependent fluorescence. At 50 microg of tetracycline ml(-1), planktonic cells of a uropathogenic E. coli (UPEC) strain developed maximal fluorescence after 7.5 to 10 min of exposure. A similar behavior was exhibited by cells in a 24- or 48-h UPEC biofilm, as examined by confocal laser microscopy, regardless of whether they lined empty spaces or occupied densely packed regions. Further, a comparison of phase-contrast and fluorescent images of corresponding biofilm zones showed that all the cells fluoresced. Thus, all the biofilm cells were exposed to tetracycline and there were no pockets within the biofilm where the antibiotic failed to reach. It also appeared unlikely that niches of reduced exposure to the antibiotic existed within the biofilms.

  17. Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt.

    PubMed

    El-Razik, K A Abd; Arafa, A A; Hedia, R H; Ibrahim, E S

    2017-06-01

    This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS) derived from normal and subclinical mastitic (SCM) buffaloes' milk in Egypt. A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]). CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline ( tet ) resistance genes followed by sequencing of positive PCR products and phylogenetic analysis. Isolation and identification of 28 (34.5%) CNS from normal and SCM buffaloes' milk, namely, Staphylococcus intermedius (39.2%), Staphylococcus xylosus (25.0%), Staphylococcus epidermidis (10.7%), Staphylococcus hominis (10.7%), and 3.5% to each of Staphylococcus sciuri , Staphylococcus hyicus , Staphylococcus lugdunensis , and Staphylococcus simulans . Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease ( nuc ) gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes ( tet K, tet L, tet M, and tet O) was detected by multiplex PCR. All isolates were negative for tet L, M, and O genes while 14 (50%) CNS isolates were positive for tet K gene, namely, S. lugdunensis (100%), S. hominis (100%), S. epidermidis (66.6%), S. intermedius (45.4%), and S. xylosus (42.8%). Nucleotide sequencing of tet K gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase positive Staphylococcus spp. CNS isolates have distinguishingly high resistance to tetracycline. Abundant tetracycline usage for

  18. Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt

    PubMed Central

    El-Razik, K. A. Abd; Arafa, A. A.; Hedia, R. H.; Ibrahim, E. S.

    2017-01-01

    Aim:: This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS) derived from normal and subclinical mastitic (SCM) buffaloes’ milk in Egypt. Materials and Methods: :: A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]). CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline (tet) resistance genes followed by sequencing of positive PCR products and phylogenetic analysis. Results:: Isolation and identification of 28 (34.5%) CNS from normal and SCM buffaloes’ milk, namely, Staphylococcus intermedius (39.2%), Staphylococcus xylosus (25.0%), Staphylococcus epidermidis (10.7%), Staphylococcus hominis (10.7%), and 3.5% to each of Staphylococcus sciuri, Staphylococcus hyicus, Staphylococcus lugdunensis, and Staphylococcus simulans. Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease (nuc) gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes (tetK, tetL, tetM, and tetO) was detected by multiplex PCR. All isolates were negative for tetL, M, and O genes while 14 (50%) CNS isolates were positive for tetK gene, namely, S. lugdunensis (100%), S. hominis (100%), S. epidermidis (66.6%), S. intermedius (45.4%), and S. xylosus (42.8%). Nucleotide sequencing of tetK gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase positive Staphylococcus spp. Conclusion:: CNS isolates have distinguishingly high resistance to

  19. 21 CFR 520.2345a - Tetracycline hydrochloride capsules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... organisms sensitive to tetracycline hydrochloride, such as bacterial gastroenteritis due to E. coli and urinary tract infections due to Staphylococcus spp. and E. coli. (3) Limitations. Federal law restricts...

  20. 21 CFR 520.2345a - Tetracycline hydrochloride capsules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... organisms sensitive to tetracycline hydrochloride, such as bacterial gastroenteritis due to E. coli and urinary tract infections due to Staphylococcus spp. and E. coli. (3) Limitations. Federal law restricts...

  1. Setting characteristics and mechanical behaviour of a calcium phosphate bone cement containing tetracycline.

    PubMed

    Ratier, A; Gibson, I R; Best, S M; Freche, M; Lacout, J L; Rodriguez, F

    2001-05-01

    Calcium phosphate cements are used for bone defect filling and they may also be used as delivery systems for active agents. The physicochemical behaviour of an ionic cement, with a final composition of hydroxyapatite, containing tetracycline hydrochloride was investigated. Chemical characterisation, X-ray diffraction analysis, compressive strength and tensile strength were performed. It is known that the antibiotic can be adsorbed on calcium phosphate compounds and the presence of chloride ions can strongly influence the behaviour of the cement. Adding more than 1% (w/w) of 95% pure tetracycline hydrochloride in the solid phase led to a cement with poor mechanical properties, but which, in addition to hydroxyapatite, contained residual starting reagents. For this reason, experiments were also performed with tetracycline previously treated with a calcium sulphate solution. Using a treated tetracycline, it was possible to introduce at least 7% (w/w) of active ingredient whilst still allowing the reaction to proceed to completion i.e. the formation of hydroxyapatite with good mechanical properties. Therefore, treating the tetracycline HCI with calcium sulphate solution prior to reaction conserved the activity of the antibiotic, limited the influence of the antibiotic on the cement evolution and retained the physical properties of the cement.

  2. One-pot carbonization synthesis of europium-doped carbon quantum dots for highly selective detection of tetracycline

    NASA Astrophysics Data System (ADS)

    Li Liu, Meng; Chen, Bin Bin; Yang, Tong; Wang, Jian; Liu, Xi Dong; Zhi Huang, Cheng

    2017-03-01

    The detection of tetracycline is of great significance because of its damaging effects on human health, such as renal toxicity and hemolytic anemia. Any release of tetracycline into the surrounding environment can produce bacterial drug resistance. We develop a new sensitive and selective detection approach for tetracycline in complex water samples by preparing europium-doped carbon quantum dots (Eu-CQDs) through a simple and rapid carbonization method operating at 200 °C for 5 min. The Eu-CQDs are characterized by blue photoluminescence, excitation-wavelength-dependent emission and excellent stability. Importantly, the fluorescence of the Eu-CQDs can be quenched efficiently by tetracycline, based on the strong inner filter effect mechanism between Eu-CQDs and tetracycline, making the fluorescence intensity ratio (I 0/I) of the Eu-CQDs at 465 nm correlate linearly with the concentration of tetracycline in the range of 0.5-200 μM, with a limit of detection of 0.3 μM. This shows the broad applicability of the Eu-CQDs in pursuing the concepts of simplicity and specificity for analytical purposes.

  3. Antibiotic resistance of native and faecal bacteria isolated from rivers, reservoirs and sewage treatment facilities in Victoria, south-eastern Australia.

    PubMed

    Boon, P I; Cattanach, M

    1999-03-01

    The incidence of resistance to ampicillin, chloramphenicol, kanamycin, nalidixic acid, neomycin and streptomycin was significantly greater (P < 0.001) in native heterotrophic bacteria than in Escherichia coli isolated from a range of sites along the Yarra River in south-eastern Australia. There was no significant difference in the incidence of resistance between native and faecal bacteria to tetracycline. Both groups were almost totally resistant to penicillin. Multivariate analyses indicated little clear spatial pattern in the incidence of resistance in native bacteria from upstream vs downstream sites along the Yarra River. In contrast, E. coli isolated from upstream (rural) sites tended to have a lower incidence of resistance than isolates from downstream (urban) sites. These findings have implications for the use of antibiotic resistance as a bacteriological water quality parameter.

  4. Incidence of Quinolone Resistance Over the Period 1986 to 1998 in Veterinary Salmonella Isolates from Germany

    PubMed Central

    Malorny, Burkhard; Schroeter, Andreas; Helmuth, Reiner

    1999-01-01

    A total of 24,591 nonhuman salmonella strains isolated in Germany between 1986 and 1998 were examined for their resistance to nalidixic acid by an agar diffusion method. The rate of resistance (inhibition zone, ≤13 mm) ranged from 0.2% in 1986 to a peak of 14.8% in 1990. Between 1991 and 1998 the MICs for nalidixic acid-resistant strains ranged from more than 256 μg/ml for nalidixic acid to between 0.25 and 128 μg/ml for enrofloxacin. In the early 1990s a particularly high incidence of fluoroquinolone resistance (49.5%) was seen among isolates of Salmonella enterica serotype Typhimurium (Salmonella Typhimurium) definitive phage type 204c that mainly originated from cattle. Among isolates from poultry an increase in the incidence of nalidixic acid resistance to a peak of 14.4% was observed in 1994. This peak was due to the presence of specific resistant serotypes, mainly serotypes Hadar, Saintpaul, Paratyphi B (d-tartrate positive; formerly serotype Java) and Newport. Such strains exhibited a decreased susceptibility to enrofloxacin (MIC, 1 μg/ml). Among isolates from pigs the peak incidence of resistance was reached in 1993, with 7.5% of isolates resistant to nalidixic acid and enrofloxacin. The study demonstrates an increase in the incidence of strains that are resistant to nalidixic acid and that have decreased susceptibility to enrofloxacin after the licensing of enrofloxacin. In addition, the number of other serotypes that exhibited nalidixic acid resistance or reduced enrofloxacin susceptibility increased among the total number of isolates investigated between 1992 and 1998. PMID:10471579

  5. Evaluation of factors important in modeling plasma concentrations of tetracycline hydrochloride administered in water in swine.

    PubMed

    Mason, Sharon E; Almond, Glen W; Riviere, Jim E; Baynes, Ronald E

    2012-10-01

    To model the plasma tetracycline concentrations in swine (Sus scrofa domestica) treated with medication administered in water and determine the factors that contribute to the most accurate predictions of measured plasma drug concentrations. Plasma tetracycline concentrations measured in blood samples from 3 populations of swine. Data from previous studies provided plasma tetracycline concentrations that were measured in blood samples collected from 1 swine population at 0, 4, 8, 12, 24, 32, 48, 56, 72, 80, 96, and 104 hours and from 2 swine populations at 0, 12, 24, 48, and 72 hours hours during administration of tetracycline hydrochloride dissolved in water. A 1-compartment pharmacostatistical model was used to analyze 5 potential covariate schemes and determine factors most important in predicting the plasma concentrations of tetracycline in swine. 2 models most accurately predicted the tetracycline plasma concentrations in the 3 populations of swine. Factors of importance were body weight or age of pig, ambient temperature, concentration of tetracycline in water, and water use per unit of time. The factors found to be of importance, combined with knowledge of the individual pharmacokinetic and chemical properties of medications currently approved for administration in water, may be useful in more prudent administration of approved medications administered to swine. Factors found to be important in pharmacostatistical models may allow prediction of plasma concentrations of tetracycline or other commonly used medications administered in water. The ability to predict in vivo concentrations of medication in a population of food animals can be combined with bacterial minimum inhibitory concentrations to decrease the risk of developing antimicrobial resistance.

  6. An in vitro study to assess the impact of tetracycline on the human intestinal microbiome.

    PubMed

    Jung, Ji Young; Ahn, Youngbeom; Khare, Sangeeta; Gokulan, Kuppan; Piñeiro, Silvia A; Cerniglia, Carl E

    2018-02-01

    The human intestinal microbiome, a generally stable ecosystem, could be potentially altered by the ingestion of antimicrobial drug residues in foods derived from animals. Data and the scientific published literature on the effects of antimicrobial residues on the human intestinal microbiome are reviewed by national regulatory authorities as part of the human food safety evaluation of veterinary antimicrobial agents used in food-producing animals. In this study, we determined if tetracycline, at low residue concentrations, could impact the human intestinal microbiome structure and the resistance-gene profile, following acute and subchronic exposure. The effects of 0.15, 1.5, 15, and 150 μg/ml of tetracycline, after 24 h and 40 days of exposure, in 3% human fecal suspensions, collected from three individuals (A, B, and C) were investigated using in vitro batch cultures. Results were variable, with either no change or minor changes in total bacterial 16S rRNA gene copies after exposure of fecal samples to tetracycline, because of the inter-individual variation of human gastrointestinal tract microbiota. Bacterial community analysis using rRNA-based pyrosequencing revealed that Firmicutes and Bacteroidetes were the predominant phyla in the three fecal samples; the ratio of phylotypes varied among individuals. The evaluation of bacterial community changes at the genus level, from control to tetracycline-treated fecal samples, suggested that tetracycline under the conditions of this study could lead to slight differences in the composition of intestinal microbiota. The genus Bacteroides (of the Bacteroidetes) was consistently altered from 1.68 to 5.70% and 4.82-8.22% at tetracycline concentrations of 0.15 μg/ml or above at both time points for individual A, respectively, and increased 5.13-13.50% and 10.92-22.18% for individual B, respectively. Clostridium family XI increased 3.50-25.34% in the presence of tetracycline at 40 days for individual C. Principal

  7. Koserella trabulsii, a new genus and species of Enterobacteriaceae formerly known as Enteric Group 45.

    PubMed Central

    Hickman-Brenner, F W; Huntley-Carter, G P; Fanning, G R; Brenner, D J; Farmer, J J

    1985-01-01

    The name Koserella trabulsii is proposed for a group of Enterobacteriaceae formerly called Enteric Group 45. This group consists of 12 strains that were originally identified as atypical Hafnia alvei. K. trabulsii strains were negative for indole production, Voges-Proskauer, H2S production, urea hydrolysis, phenylalanine deaminase, and acid production from glycerol, lactose, sucrose, and D-sorbitol; they were positive for methyl red, citrate (Simmons), lysine and ornithine decarboxylases, arginine dihydrolase (negative in 1 to 2 days and positive in 3 to 7 days), and acid production from cellobiose and melibiose; and they were resistant to the Hafnia-specific bacteriophage of Guinée and Valkenburg. They were tested for DNA relatedness by the hydroxyapatite method with 32PO4-labeled DNA from the designated type strain (CDC 3349-72, ATCC 35313). The 12 strains were 87 to 99% related in 60 degrees C reactions. Relatedness of K. trabulsii to 71 DNA hybridization reference strains of representative species of Enterobacteriaceae was 4 to 37%. It was 15 to 16% related to H. alvei. All strains were susceptible to nalidixic acid, sulfadiazine, gentamicin, kanamycin, and chloramphenicol, and 83% were susceptible to nalidixic acid, sulfadiazine, gentamicin, kanamycin, and chloramphenicol, and 83% were susceptible to tetracycline. Most of the strains were resistant or intermediate to penicillin, ampicillin, carbenicillin, colistin, and cephalothin. Five of the strains were isolated from wounds, three were from the respiratory tract, and one each was from a stool, knee fluid, water, and an unknown source. The clinical significance of this organism is not known; therefore, future studies should focus on its isolation and its relationship to human disease. PMID:3968202

  8. Antimicrobial Susceptibility of Escherichia coli Isolated from Fresh-Marketed Nile Tilapia (Oreochromis niloticus)

    PubMed Central

    Rocha, Rafael dos Santos; Leite, Lana Oliveira; de Sousa, Oscarina Viana; Vieira, Regine Helena Silva dos Fernandes

    2014-01-01

    The contamination of seafood by bacteria of fecal origin, especially Escherichia coli, is a widely documented sanitary problem. The objective of the present study was to isolate E. coli strains from the gills, muscle, and body surface of farmed Nile tilapias (Oreochromis niloticus) fresh-marketed in supermarkets in Fortaleza (Ceará, Brazil), to determine their susceptibility to antibiotics of different families (amikacin, gentamicin, imipenem, cephalothin, cefotaxime, ciprofloxacin, aztreonam, ampicillin, nalidixic acid, tetracycline, and sulfametoxazol-trimetoprim), and to determine the nature of resistance by plasmid curing. Forty-four strains (body surface = 25, gills = 15, muscle = 4) were isolated, all of which were susceptible to amikacin, aztreonam, cefotaxime, ciprofloxacin, gentamicin, and imipenem. Gill and body surface samples yielded 11 isolates resistant to ampicillin, tetracycline, and sulfametoxazol-trimetoprim, 4 of which of plasmidial nature. The multiple antibiotic resistance index was higher for strains isolated from body surface than from gills. The overall high antibiotic susceptibility of E. coli strains isolated from fresh-marketed tilapia was satisfactory, although the occasional finding of plasmidial resistance points to the need for close microbiological surveillance of the farming, handling, and marketing conditions of aquaculture products. PMID:24808957

  9. Prevalence of Campylobacter species in wild birds of South Korea.

    PubMed

    Kwon, Yong-Kuk; Oh, Jae-Young; Jeong, Ok-Mi; Moon, Oun-Kyoung; Kang, Min-Su; Jung, Byeong-Yeal; An, Byung-Ki; Youn, So-Youn; Kim, Hye-Ryoung; Jang, Il; Lee, Hee-Soo

    2017-10-01

    Campylobacter species cause human gastrointestinal infections worldwide. They commonly inhabit intestines of avian species including wild birds. They might play a role in the spread of infections to humans and other bird species. The prevalence of Campylobacter species in 2164 faecal samples of wild birds (representing 71 species and 28 families) captured across the Korean peninsula was evaluated in this study. The overall prevalence was 15.3% (332/2164). Bird species belonging to the family Charadriidae had the highest isolation rate (30.0%), followed by those belonging to the families Ardeidae (26.4%), Turdidae (21.9%), and Anatidae (15.3%). The prevalence of Campylobacter spp. differed significantly according to migratory habit. Stopover birds were the most commonly infected (19.0%), followed by winter migratory (16.7%) and summer migratory birds (12.3%). However, indigenous birds showed very low prevalence (2.7%). Antimicrobial susceptibility tests were performed for 213 isolates. Results showed that Campylobacter jejuni isolates (n = 169) exhibited resistance to nalidixic acid (5.3%), ciprofloxacin (3.0%), and tetracycline (1.8%), while Campylobacter lari (n = 1) displayed resistance to nalidixic acid and ciprofloxacin. However, all Campylobacter coli isolates (n = 20) were susceptible to all antimicrobials tested. This is the first report on the prevalence of Campylobacter species in wild birds that seasonally or indigenously inhabit the Korean peninsula. Our results indicate that the overall prevalence of Campylobacter in wild birds is moderate. Therefore, birds might serve as significant reservoirs for Campylobacter pathogens.

  10. 21 CFR 520.2345d - Tetracycline powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... bacterial enteritis (scours) caused by E. coli and bacterial pneumonia associated with Pasteurella spp., A... gallisepticum and E. coli; control of infectious synovitis caused by M. synoviae susceptible to tetracycline.... Control and treatment of bacterial enteritis (scours) caused by Escherichia coli and bacterial pneumonia...

  11. Planar chromatography mediated screening of tetracycline and fluoroquinolone antibiotics in milk by fluorescence and mass selective detection.

    PubMed

    Chen, Yisheng; Schwack, Wolfgang

    2013-10-18

    A rapid and efficient method for preliminary screening of four tetracyclines (tetracycline, chlortetracycline, oxytetracycline, doxycline) and three fluoroquinolones (enrofloxacin, ciprofloxacin, marbofloxacin), mostly detected in milk, by high-performance thin-layer chromatography-fluorescence detection and electrospray ionization mass spectrometry (HPTLC-FLD-ESI/MS) is highlighted. The optimized separation of the target antibiotics on ethylenediamine tetraacetic acid modified silica gel plates showed marked benefits for screening purposes. Besides, selective and sensitive densitometry in fluorescence mode was established with excitation at 366nm for the tetracyclines, 300nm for enrofloxacin and ciprofloxacin, and 280nm for marbofloxacin. Limits of detection (LOD) and quantitation (LOQ) with 95% confidence were in the range of 12-25 and 45-95μg/kg, respectively, in milk samples. Recoveries of target antibiotics from milk samples spiked at three critical levels (50, 100 and 150μg/kg) ranged from 76% to 105%. More importantly, a mass selective detection (MSD) was established as additional tool for confirmatory purposes. Using the elution-head based TLC-MS interface, the optimized elution flow consisting of acetonitrile/ammonium formate buffer (9/1, v/v) at a rate of 0.3mL/min enabled time-dependent resolution of analytes from the major interfering compounds, thus circumventing serious ion suppression effects. The established MSD assay also offered high sensitivity (25μg/kg) for confirmation, meeting Commission Regulation (EU) No. 37/2010. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Genotoxicity of tetracycline as an emerging pollutant on root meristem cells of wheat (Triticum aestivum L.).

    PubMed

    Xie, Xiujie; Zhou, Qixing; Bao, Qiuhua; He, Zhangchun; Bao, Yanyu

    2011-08-01

    Increasing attention has been paid to antibiotic contamination as an increasingly serious environmental issue. Tetracycline has been widely used for decades in human and veterinary medicines, with incremental residues in the environment and adverse influences on living organisms. In the present study, the genetic toxicity of tetracycline was investigated using a bioassay method with wheat (Triticum aestivum L.) root-meristem cells at a concentration range of 0.25-300 mg L(-1) and exposure times of 24, 48, and 72 h. The results indicated that tetracycline at lower concentrations (0.25-1 mg L(-1) ) stimulated cell mitotic division, whereas at 50-300 mg L(-1) concentration caused a concentration-related decrease in mitotic index (MI). The lower tetracycline concentrations induced a slight increase in the frequency of micronucleus (MN), chromosomal aberration (CA), and sister chromatid exchange (SCE) in wheat root tips. However, there were significant increases in these indices at higher concentrations in concentration- and time-dependent manners, including the frequencies of MN (25-200 mg L(-1) ), CA (10-200 mg L(-1) ), and SCE (5-200 mg L(-1) ), respectively. The inducement of MN, CA, and SCE decreased at 250 and 300 mg L(-1) due to acute cell toxicity for all tested times. Comparatively, SCE was the most sensitive, followed by CA, with MN the least sensitive to the genotoxicity of tetracycline in wheat. These results imply that tetracycline may be genotoxic to plant cells, and exposure to tetracycline may pose a genotoxic risk to living organisms. The results also suggest that the wheat bioassay was efficient, simple, and reproducible in monitoring the genotoxicity of tetracycline in the environment. Copyright © 2010 Wiley Periodicals, Inc.

  13. [Sclerosing therapy of testicular hydrocele with tetracycline].

    PubMed

    Losada Guerra, J L; Hernández Navarro, E

    1992-12-01

    Twenty-six patients, aged 38 to 78 years, with testicular hydrocele were treated by aspiration, punction and tetracycline instillation. The cure rate was 79%. Inflammation of the scrotum was observed in all of the cases. Due to recurrence two patients underwent surgery, which revealed a hematocele.

  14. Antimicrobial resistance in Shigella spp. causing traveller's diarrhoea (1995-2010): a retrospective analysis.

    PubMed

    Pons, M J; Gomes, C; Martínez-Puchol, S; Ruiz, L; Mensa, L; Vila, J; Gascón, J; Ruiz, J

    2013-01-01

    Shigellosis is a global human health problem causing an important morbidity among travellers returning from tropical areas. This study was aimed to describe the evolution of antimicrobial resistance profile in Shigella spp. isolated between the years 1995-2010 in patients with traveller's diarrhoea (TD) returning from tropical areas. The levels of antimicrobial resistance were tested in a total of 191 Shigella spp. isolated during the period from 1995 to 2010. A decrease of cases of diarrhoea caused by Shigella has been observed in recent years. A wide spectrum of antibiotic resistance was observed among Shigella spp. These isolates showed high levels of resistance to tetracycline (84%), co-trimoxazole (75.5%), and ampicillin (45.5%). The resistance was low to ciprofloxacin (2.1%), azithromycin (3.9%) and furazolidone (8.4%). According to the period, in the case of ampicillin, amoxicillin plus clavulanic acid, chloramphenicol, values of resistance were significantly decreasing from 1995-2000 to 2001-2010, (62.5% vs. 28.4%, 19.8% vs. 6.6%, 23.4 vs. 10.4%, respectively). Meanwhile in nalidixic acid and tetracycline the evolution of resistance has increased over time. A decrease in the isolation number of Shigella spp. causing TD has been observed. Differential trends in the evolution of the levels of resistance to the tested antibacterial agents have been observed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Content of biogenic amines in Lemna minor (common duckweed) growing in medium contaminated with tetracycline.

    PubMed

    Baciak, Michał; Sikorski, Łukasz; Piotrowicz-Cieślak, Agnieszka I; Adomas, Barbara

    2016-11-01

    Aquatic plants are continuously exposed to a variety of stress factors. No data on the impact of antibiotics on the biogenic amines in duckweed (Lemna minor) have been available so far, and such data could be significant, considering the ecological role of this plant in animal food chains. In the tissues of control (non-stressed) nine-day-old duckweed, the following biogenic amines were identified: tyramine, putrescine, cadaverine, spermidine and spermine. Based on the tetracycline contents and the computed EC values, the predicted toxicity units have been calculated. The obtained results demonstrated phytoxicity caused by tetracycline in relation to duckweed growth rate, yield and the contents of chlorophylls a and b. The carotenoid content was not modified by tetracycline. It was found that tetracycline as a water pollutant was a stress factor triggering an increase in the synthesis of amines. Tetracycline at 19, 39 and 78μM concentrations increased biogenic amine synthesis by 3.5 times. Although the content of tyramine increased fourteen times with the highest concentration of the drug (and of spermidine - only three-fold) the increase of spermidine was numerically the highest. Among the biogenic amines the most responsive to tetracycline were spermine and tyramine, while the least affected were putrescine and spermidine. Despite putrescine and spermidine being the least sensitive, their sum of contents increased five-fold compared to the control. These studies suggest that tetracycline in water reservoirs is taken up by L. minor as the antibiotic clearly modifies the metabolism of this plant and it may likely pose a risk. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Bicyclol attenuates tetracycline-induced fatty liver associated with inhibition of hepatic ER stress and apoptosis in mice.

    PubMed

    Yao, Xiao-Min; Li, Yue; Li, Hong-Wei; Cheng, Xiao-Yan; Lin, Ai-Bin; Qu, Jun-Ge

    2016-01-01

    Endoplasmic reticulum (ER) stress is known to be involved in the development of several metabolic disorders, including non-alcoholic fatty liver disease (NAFLD). Tetracycline can cause hepatic steatosis, and ER stress may be involved in tetracycline-induced fatty liver. Our previous study showed that bicyclol has been proven to protect against tetracycline-induced fatty liver in mice, and ER stress may also be involved in bicyclol's hepatoprotective effect. Therefore, this study was performed to investigate the underlying mechanisms associated with ER stress and apoptosis, by which bicyclol attenuated tetracycline-induced fatty liver in mice. Bicyclol (300 mg/kg) was given to mice by gavage 3 times. Tetracycline (200 mg/kg, intraperitoneally) was injected at 1 h after the last dose of bicyclol. At 6 h and 24 h after single dose of tetracycline injection, serum ALT, AST, TG, CHO and hepatic histopathological examinations were performed to evaluate liver injuries. Hepatic steatosis was assessed by the accumulation of hepatic TG and CHO. Moreover, hepatic apoptosis and ER stress related markers were determined by TUNEL, real-time PCR, and western blot. As a result, bicyclol significantly protected against tetracycline-induced fatty liver as evidenced by the decrease of elevated serum transaminases and hepatic triglyceride, and the attenuation of histopathological changes in mice. In addition, bicyclol remarkably alleviated hepatic apoptosis and the gene expression of caspase-3, and increased the gene expression of XIAP. The gene expressions of ER stress-related markers, including CHOP, GRP78, IRE-1α, and ATF6, which were downregulated by bicyclol pretreatment in tetracycline-injected mice. These results suggested that bicyclol protected tetracycline-induced fatty liver partly due to its ability of anti-apoptosis associated with ER stress.

  17. Minocycline and doxycycline, but not other tetracycline-derived compounds, protect liver cells from chemical hypoxia and ischemia/reperfusion injury by inhibition of the mitochondrial calcium uniporter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schwartz, Justin; Holmuhamedov, Ekhson; Zhang, Xun

    Minocycline, a tetracycline-derived compound, mitigates damage caused by ischemia/reperfusion (I/R) injury. Here, 19 tetracycline-derived compounds were screened in comparison to minocycline for their ability to protect hepatocytes against damage from chemical hypoxia and I/R injury. Cultured rat hepatocytes were incubated with 50 μM of each tetracycline-derived compound 20 min prior to exposure to 500 μM iodoacetic acid plus 1 mM KCN (chemical hypoxia). In other experiments, hepatocytes were incubated in anoxic Krebs–Ringer–HEPES buffer at pH 6.2 for 4 h prior to reoxygenation at pH 7.4 (simulated I/R). Tetracycline-derived compounds were added 20 min prior to reperfusion. Ca{sup 2+} uptake wasmore » measured in isolated rat liver mitochondria incubated with Fluo-5N. Cell killing after 120 min of chemical hypoxia measured by propidium iodide (PI) fluorometry was 87%, which decreased to 28% and 42% with minocycline and doxycycline, respectively. After I/R, cell killing at 120 min decreased from 79% with vehicle to 43% and 49% with minocycline and doxycycline. No other tested compound decreased killing. Minocycline and doxycycline also inhibited mitochondrial Ca{sup 2+} uptake and suppressed the Ca{sup 2+}-induced mitochondrial permeability transition (MPT), the penultimate cause of cell death in reperfusion injury. Ru360, a specific inhibitor of the mitochondrial calcium uniporter (MCU), also decreased cell killing after hypoxia and I/R and blocked mitochondrial Ca{sup 2+} uptake and the MPT. Other proposed mechanisms, including mitochondrial depolarization and matrix metalloprotease inhibition, could not account for cytoprotection. Taken together, these results indicate that minocycline and doxycycline are cytoprotective by way of inhibition of MCU. - Highlights: • Minocycline and doxycycline are the only cytoprotective tetracyclines of those tested • Cytoprotective tetracyclines inhibit the MPT and mitochondrial calcium and iron uptake.

  18. Efficacy of Ciprofloxacin for Treatment of Cholera Associated with Diminished Susceptibility to Ciprofloxacin to Vibrio cholerae O1.

    PubMed

    Khan, Wasif Ali; Saha, Debasish; Ahmed, Sabeena; Salam, Mohammed Abdus; Bennish, Michael Louis

    2015-01-01

    We identified a poor clinical response to treatment of cholera with a single 1 g dose of ciprofloxacin, a standard treatment for cholera. To determine reasons for the poor response and better therapeutic approaches we examined the minimal inhibitor concentration (MIC, n = 275) and disc-diffusion zone sizes (n = 205) for ciprofloxacin and nalidixic acid of V. cholerae O1 strains isolated in Bangladesh from 1994 to 2012, and reexamined data from 161 patients infected with Vibrio cholerae O1 recruited in four clinical trials who received single- or multiple-dose ciprofloxacin for treatment of cholera and compared their clinical response to the V. cholerae O1 susceptibility. Although all 275 isolates of V. cholerae O1 remained susceptible to ciprofloxacin using standard MIC and disc-diffusion thresholds, the MIC90 to ciprofloxacin increased from 0.010 in 1994 to 0.475 μgm/ml in 2012. Isolates became frankly resistant to nalidixic with the MIC90 increasing from 21 μgm/ml in 1994 to >256 μgm/ml and 166 of 205 isolates from 1994 to 2005 being frankly resistant using disc-diffusion testing. Isolates resistant to nalidixic acid by disc-diffusion testing had a median ciprofloxacin MIC of 0.190 μgm/ml (10th-90th centiles 0.022 to 0.380); nalidixic acid-susceptible isolates had a median ciprofloxacin MIC of 0.002 (0.002 to 0.012).The rate of clinical success with single-dose ciprofloxacin treatment for nalidixic acid-susceptible strains was 94% (61 of 65 patients) and bacteriologic success 97% (63/65) compared to 18% (12/67) and 8% (5/67) respectively with nalidixic acid-resistant strains (P<0.001 for both comparisons). Multiple-dose treatment with ciprofloxacin had 86% and 100% clinical and bacteriologic success rates respectively in patients infected with nalidixic acid-susceptible strains of V. cholerae O1 compared to clinical success 67% and bacteriologic success 60% with nalidixic acid-resistant strains. Single-dose ciprofloxacin is not effective for treating cholera

  19. Antibiotic resistance of lactic acid bacteria and Bifidobacterium spp. isolated from dairy and pharmaceutical products.

    PubMed

    D'Aimmo, Maria Rosaria; Modesto, Monica; Biavati, Bruno

    2007-04-01

    The outlines of antibiotic resistance of some probiotic microorganisms were studied. This study was conducted with the double purpose of verifying their ability to survive if they are taken simultaneously with an antibiotic therapy and to increase the selective properties of suitable media for the isolation of samples containing mixed bacterial populations. We isolated from commercial dairy and pharmaceutical products, 34 strains declared as probiotics, belonging to the genera Bifidobacterium and Lactobacillus, and 21 strains of starter culture bacteria. All the microorganisms have been compared by electrophoresis of the soluble proteins for the purpose of identifying them. A Multiplex-PCR with genus- and species-specific primers was used to detect for Bifidobacterium animalis subsp. lactis presence. All bifidobacteria were B. animalis subsp. lactis except one Bifidobacterium longum. Sometimes the identification showed that the used strain was not the one indicated on the label. The lactobacilli were Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus delbrueckii subsp. bulgaricus. The streptococci were all Streptococcus thermophilus. The minimal inhibitory concentration (MIC) of 24 common antibiotic substances has been valued by the broth microdilution method. All tested strains were susceptible to ampicillin, bacitracin, clindamycin, dicloxacillin, erytromycin, novobiocin, penicillin G, rifampicin (MIC(90) ranging from 0.01 to 4 microg/ml); resistant to aztreonam, cycloserin, kanamycin, nalidixic acid, polymyxin B and spectinomycin (MIC(90) ranging from 64 to >1000 microg/ml). The susceptibility to cephalothin, chloramphenicol, gentamicin, lincomycin, metronidazole, neomycin, paromomycin, streptomycin, tetracycline and vancomycin was variable and depending on the species.

  20. Elimination patterns of worldwide used sulfonamides and tetracyclines during anaerobic fermentation.

    PubMed

    Spielmeyer, Astrid; Breier, Bettina; Groißmeier, Kathrin; Hamscher, Gerd

    2015-10-01

    Antibiotics such as sulfonamides and tetracyclines are frequently used in veterinary medicine. Due to incomplete absorption in the animal gut and/or unmetabolized excretion, the substances can enter the environment by using manure as soil fertilizer. The anaerobic fermentation process of biogas plants is discussed as potential sink for antibiotic compounds. However, negative impacts of antibiotics on the fermentation process are suspected. The elimination of sulfadiazine, sulfamethazine, tetracycline and chlortetracycline in semi-continuous lab-scale fermenters was investigated. Both biogas production and methane yield were not negatively affected by concentrations up to 38 mg per kg for sulfonamides and 7 mg per kg for tetracyclines. All substances were partly eliminated with elimination rates between 14% and 89%. Both matrix and structure of the target molecule influenced the elimination rate. Chlortetracycline was mainly transformed into iso-chlortetracycline. In all other cases, the elimination pathways remained undiscovered; however, sorption processes seem to have a negligible impact. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. New hemolysin (gamma) produced by Escherichia coli.

    PubMed

    Walton, J R; Smith, D H

    1969-04-01

    A new hemolysin (gamma) of Escherichia coli, active in the absence of viable bacteria, has been recognized in mutants resistant to nalidixic acid. Nalidixic acid affects either the production or release of the hemolysin.

  2. Sorption of tetracycline on biochar derived from rice straw under different temperatures

    PubMed Central

    Wang, Hua; Chu, Yixuan; Huang, Fang; Song, Yali; Xue, Xiangdong

    2017-01-01

    Biochars produced from the pyrolysis of waste biomass under limited oxygen conditions could serve as adsorbents in environmental remediation processes. Biochar samples derived from rice straw that were pyrolyzed at 300 (R300), 500 (R500) and 700°C (R700) were used as adsorbents to remove tetracycline from an aqueous solution. Both the Langmuir and Freundlich models fitted the adsorption data well (R2 > 0.919). The adsorption capacity increased with pyrolysis temperature. The R500 and R700 samples exhibited relative high removal efficiencies across a range of initial tetracycline concentrations (0.5mg/L-32mg/L) with the maximum (92.8%–96.7%) found for adsorption on R700 at 35°C. The relatively high surface area of the R700 sample and π–π electron-donor acceptor contributed to the high adsorption capacities. A thermodynamic analysis indicated that the tetracycline adsorption process was spontaneous and endothermic. The pH of solution was also found to influence the adsorption processes; the maximum adsorption capacity occurred at a pH of 5.5. These experimental results highlight that biochar derived from rice straw is a promising candidate for low-cost removal of tetracycline from water. PMID:28792530

  3. Water-flow variation and pharmacoepidemiology of tetracycline hydrochloride administration via drinking water in swine finishing farms.

    PubMed

    Dorr, Paul M; Nemechek, Megan S; Scheidt, Alan B; Baynes, Ronald E; Gebreyes, Wondwossen A; Almond, Glen W

    2009-08-01

    To evaluate variation of drinking-water flow rates in swine finishing barns and the relationship between drinker flow rate and plasma tetracycline concentrations in pigs housed in different pens. Cross-sectional (phase 1) and cohort (phase 2) studies. 13 swine finishing farms (100 barns with 7,122 drinkers) in phase 1 and 100 finishing-stage pigs on 2 finishing farms (1 barn/farm) in phase 2. In phase 1, farms were evaluated for water-flow variation, taking into account the following variables: position of drinkers within the barn, type of drinker (swing or mounted), pig medication status, existence of designated sick pen, and existence of leakage from the waterline. In phase 2, blood samples were collected from 50 pigs/barn (40 healthy and 10 sick pigs) in 2 farms at 0, 4, 8, 24, 48, and 72 hours after initiation of water-administered tetracycline HCl (estimated dosage, 22 mg/kg [10 mg/lb]). Plasma tetracycline concentrations were measured via ultraperformance liquid chromatography. Mean farm drinker flow rates ranged from 1.44 to 2.77 L/min. Significant differences in flow rates existed according to drinker type and whether tetracycline was included in the water. Mean drinker flow rates and plasma tetracycline concentrations were significantly different between the 2 farms but were not different between healthy and sick pigs. The plasma tetracycline concentrations were typically < 0.3 microg/mL. Many factors affected drinker flow rates and therefore the amount of medication pigs might have received. Medication of pigs with tetracycline through water as performed in this study had questionable therapeutic value.

  4. High-level tetracycline resistance mediated by efflux pumps Tet(A) and Tet(A)-1 with two start codons.

    PubMed

    Wang, Weixia; Guo, Qinglan; Xu, Xiaogang; Sheng, Zi-ke; Ye, Xinyu; Wang, Minggui

    2014-11-01

    Efflux is the most common mechanism of tetracycline resistance. Class A tetracycline efflux pumps, which often have high prevalence in Enterobacteriaceae, are encoded by tet(A) and tet(A)-1 genes. These genes have two potential start codons, GTG and ATG, located upstream of the genes. The purpose of this study was to determine the start codon(s) of the class A tetracycline resistance (tet) determinants tet(A) and tet(A)-1, and the tetracycline resistance level they mediated. Conjugation, transformation and cloning experiments were performed and the genetic environment of tet(A)-1 was analysed. The start codons in class A tet determinants were investigated by site-directed mutagenesis of ATG and GTG, the putative translation initiation codons. High-level tetracycline resistance was transferred from the clinical strain of Klebsiella pneumoniae 10-148 containing tet(A)-1 plasmid pHS27 to Escherichia coli J53 by conjugation. The transformants harbouring recombinant plasmids that carried tet(A) or tet(A)-1 exhibited tetracycline MICs of 256-512 µg ml(-1), with or without tetR(A). Once the ATG was mutated to a non-start codon, the tetracycline MICs were not changed, while the tetracycline MICs decreased from 512 to 64 µg ml(-1) following GTG mutation, and to ≤4 µg ml(-1) following mutation of both GTG and ATG. It was presumed that class A tet determinants had two start codons, which are the primary start codon GTG and secondary start codon ATG. Accordingly, two putative promoters were predicted. In conclusion, class A tet determinants can confer high-level tetracycline resistance and have two start codons. © 2014 The Authors.

  5. Pharmacodynamics of Doxycycline and Tetracycline against Staphylococcus pseudintermedius: Proposal of Canine-Specific Breakpoints for Doxycycline

    PubMed Central

    Papich, Mark G.; Turnidge, John; Guardabassi, Luca

    2013-01-01

    Doxycycline is a tetracycline that has been licensed for veterinary use in some countries, but no clinical breakpoints are available for veterinary pathogens. The objectives of this study were (i) to establish breakpoints for doxycycline and (ii) to evaluate the use of tetracycline as a surrogate to predict the doxycycline susceptibility of Staphylococcus pseudintermedius isolates. MICs and inhibition zone diameters were determined for 168 canine S. pseudintermedius isolates according to Clinical and Laboratory Standards Institute (CLSI) standards. Tetracycline resistance genes were detected by PCR, and time-kill curves were determined for representative strains. In vitro pharmacodynamic and target animal pharmacokinetic data were analyzed by Monte Carlo simulation (MCS) for the development of MIC interpretive criteria. Optimal zone diameter breakpoints were defined using the standard error rate-bounded method. The two drugs displayed bacteriostatic activity and bimodal MIC distributions. Doxycycline was more active than tetracycline in non-wild-type strains. MCS and target attainment analysis indicated a certainty of ≥90% for attaining an area under the curve (AUC)/MIC ratio of >25 with a standard dosage of doxycycline (5 mg/kg of body weight every 12 h) for strains with MICs of ≤0.125 μg/ml. Tetracycline predicted doxycycline susceptibility, but current tetracycline breakpoints were inappropriate for the interpretation of doxycycline susceptibility results. Accordingly, canine-specific doxycycline MIC breakpoints (susceptible, ≤0.125 μg/ml; intermediate, 0.25 μg/ml; resistant, ≥0.5 μg/ml) and zone diameter breakpoints (susceptible, ≥25 mm; intermediate, 21 to 24 mm; resistant, ≤20 mm) and surrogate tetracycline MIC breakpoints (susceptible, ≤0.25 μg/ml; intermediate, 0.5 μg/ml; resistant, ≥1 μg/ml) and zone diameter breakpoints (susceptible, ≥23 mm; intermediate, 18 to 22 mm; resistant, ≤17 mm) were proposed based on the data generated

  6. Instability of chlorophyll in yellow lupin seedlings grown in soil contaminated with ciprofloxacin and tetracycline.

    PubMed

    Rydzyński, Dariusz; Piotrowicz-Cieślak, Agnieszka I; Grajek, Hanna; Michalczyk, Dariusz J

    2017-10-01

    With increasing soil concentrations of ciprofloxacin and tetracycline a decrease of leaf chlorophyll content was observed. Tetracycline was more detrimental than ciprofloxacin. The chlorophyll content in plants growing for ten days on a tetracycline containing soil decreased by 68%. The decrease of chlorophyll concentration was even sharper in new leaves that formed after application of the antibiotic (up to 81% drop). The comparison of absorption spectra of commercial, reagent grade chlorophyll, alone and incubated with antibiotics, has shown that ciprofloxacin and tetracycline can react directly with chlorophyll and decrease its concentration by 47.7% and 48.5%, respectively. The changes in fluorescence spectra confirmed the formation of chlorophyll degradation product. The chlorophyll decay was a second order reaction and depended on antibiotic concentration and duration of exposure. Reaction rate constants differed with antibiotics and their soil concentrations. With increasing contents of antibiotics in soil the constant of chlorophyll degradation rate in lupin plants increased from k = 870 M -1 day -1 for 3 mg ciprofloxacin to k = 2490 M -1 day -1 for 90 mg ciprofloxacin, and in the case of tetracycline the reaction rate constant increased from k = 1330 M -1 day -1 to k = 2910 M -1 day -1 . The sensitivity of chlorophyll to ciprofloxacin and tetracycline was confirmed by determining EC and TU indices. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Use of DNA probes to study tetracycline resistance determinants in gram-negative bacteria from swine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, C.Y.

    1989-01-01

    Specific {sup 32}P-labeled DNA probes were prepared and used to evaluate the distribution of tetracycline resistance determinants carried by gram-negative enteric bacteria isolated from pigs in 3 swine herds with different histories of antibiotic exposure. Plasmid DNA, ranging in size from 2.1 to 186 Kb, was observed in over 84% of 114 isolates studied. Two of 78 tetracycline resistant strains did not harbor plasmids. The DNA probes were isolated from plasmids pSL18, pRT29/Tn10, pBR322 and pSL106, respectively, and they represented class A, B, C and D tetracycline resistance determinants. Hybridization conditions using 0.5X SSPE at 65{degrees}C minimize cross-hybridization between themore » different class of tetracycline resistance genes. Cross-hybridization between class A and class C determinants could be distinguished by simultaneous comparison of the intensity of their hybridization signals. Plasmids from over 44% of the tetracycline resistant isolates did not hybridize to DNA probes for the determinants tested. Class B determinant occurred more frequently than class A or C. None of the isolates hybridized with the class D probe.« less

  8. New Hemolysin (γ) Produced by Escherichia coli

    PubMed Central

    Walton, John R.; Smith, David H.

    1969-01-01

    A new hemolysin (γ) of Escherichia coli, active in the absence of viable bacteria, has been recognized in mutants resistant to nalidixic acid. Nalidixic acid affects either the production or release of the hemolysin. Images PMID:4891808

  9. Tetracycline sclerotherapy of hydroceles and epididymal cysts. Long-term results.

    PubMed

    Honnens de Lichtenberg, M; Miskowiak, J; Krogh, J

    1990-01-01

    Fourty patients with 32 hydroceles and 11 epididymal cysts were treated by aspiration and instillation of tetracycline. After a follow up period of 24-39 months the cure rate was 77%. Most of the early recurrences were the results of chemical inflammation and vanished spontaneously. This group should therefore not be operated on until three months after their initial treatment. As aspiration of the fluid had allowed palpation of the testis and cytological examination, only a small proportion of patients with recurrences wanted further treatment. We therefore recommend tetracycline sclerotherapy because it is quick, easy, safe, and effective in the long as well as the short term.

  10. Repurposing of tetracyclines to overcome resistance pathways associated with photochemotherapy in cancer (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Liu, Joyce; Huang, Huang-Chiao; Rizvi, Imran; Hasan, Tayyaba

    2016-03-01

    Given the consistently poor prognoses for some of the most difficult-to-treat cancers, rapidly translatable treatment regimens that offer improvements in outcomes are much needed. The repurposing of FDA approved non-cancer drugs presents an opportunity to design clinically feasible, novel combinations of therapies with a mechanistic rationale, to overcome resistance and survival pathways that render many current treatments ineffective. Tetracyclines are a class of antibiotics that demonstrate potential for such repurposing, as they have also been shown by others to affect a wide range of targets in cancer. Notably, the unique structure of tetracyclines allows them to act through both light activated and non-light mediated mechanisms. While light activation of tetracyclines can result in singlet oxygen production, their non-light mediated targets include inhibition of DNA repair enzymes and modulation of hypoxia-inducible markers, among others. With these mechanisms in mind, we seek to elucidate the benefit of including tetracyclines as part of an already promising, mechanistically cooperative photochemotherapy combination for ovarian cancer. In ovarian cancer, the dismal rates of recurrence and survival associated with the aggressive disease further emphasize the need to mechanistically reinforce treatments regimens. Thus, the results will highlight insights into the cooperative effect of repurposed tetracyclines on treatment response and molecular markers, both in vitro and in a challenging mouse model of disseminated ovarian cancer.

  11. Effect of tetracycline and UV radiation on melanization and antioxidant status of melanocytes.

    PubMed

    Rok, Jakub; Buszman, Ewa; Delijewski, Marcin; Otręba, Michał; Beberok, Artur; Wrześniok, Dorota

    2015-07-01

    Tetracycline is a semisynthetic antibiotic and is used in several types of infections against both gram-positive and gram-negative bacteria. This therapy is often associated with phototoxic reactions that occur after exposure to UV radiation and lead to photo-onycholysis, pseudoporphyria, solar urticaria and the fixed drug eruption in the skin. The phototoxic reactions may be related to the melanin content which, on one side may bind drugs - leading to their accumulation, and on the other side, they have photoprotective and antioxidant properties. In this study the effect of tetracycline and UVA irradiation on cell viability, biosynthesis of melanin and antioxidant defense system in cultured normal human epidermal melanocytes (HEMn-DP) was analyzed. The viability of the cells treated with tetracycline and exposed to UVA radiation decreased in a drug concentration-dependent manner. At the same time, the induction of the melanization process was observed. The significant alterations in antioxidant defense system, on the basis of changes in SOD, CAT and GPx activities, were stated. The obtained results may give explanation for the phototoxic effects of tetracycline therapy observed in skin cells exposed to UVA radiation. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Combined effect of a mixture of tetracycline, acid, and detergent, and Nisin against Enterococcus faecalis and Actinomyces viscosus biofilms

    PubMed Central

    Balto, Hanan A.; Shakoor, Zahid A.; Kanfar, Maha A.

    2015-01-01

    Objectives: To evaluate the combined effect of a mixture of tetracycline, acid, and detergent (MTAD) and Nisin against Enterococcus faecalis (E. faecalis) and Actinomyces viscosus (A. viscosus) biofilms. Methods: This study was conducted between June and December 2013 in collaboration with Dental Caries Research Chair, College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Single-species biofilms (n=9/species/observation period) were generated on membrane filter discs and subjected to 5, 10, or 15 minute incubation with MTADN (MTAD with 3% Nisin), 5.25% sodium hypochlorite (NaOCl), or normal saline. The colony forming units were counted using the Dark field colony counter. Results: A 100% bactericidal effect of 5.25% NaOCl was noted during the 3 observation periods; a significant reduction (p=0.000) in mean survival rates of E. faecalis (77.3+13.6) and A. viscosus (39.6+12.6) was noted after 5 minutes exposure to MTADN compared with normal saline (78000000+5291503) declining to almost no growth after 10 and 15 minutes. The survival rates of the E. faecalis and A. viscosus biofilm were no different after treatment with MTADN and 5.25% NaOCl at the 3 observation periods (p=1.000). Conclusion: A combination of MTAD and Nisin was as effective as NaOCl against E. faecalis and A. viscosus biofilms. PMID:25719587

  13. Rapid Detection of Bacterial Antibiotic Resistance: Preliminary Evaluation of PCR Assays Targeting Tetracycline Resistance Genes

    DTIC Science & Technology

    2007-08-01

    gonorrheae strain 2309 plasmid pOZ101; AF440277, Lactobacillus plantarum plasmid pMD5057; X75073, Neisseria meningitidis plasmid DNA for tet(M...tetracycline resistance tet(M) gene; AY057892, Staphylococcus aureus strain 1802 tetracycline resistance protein tet(M) gene; AY149596, Lactobacillus sakei

  14. Ultraviolet reduction of erythromycin and tetracycline resistant heterotrophic bacteria and their resistance genes in municipal wastewater.

    PubMed

    Guo, Mei-Ting; Yuan, Qing-Bin; Yang, Jian

    2013-11-01

    Antibiotic resistance in wastewater is becoming a major public health concern, but poorly understood about impact of disinfection on antibiotic resistant bacteria and antibiotic resistance genes. The UV disinfection of antibiotic resistant heterotrophic bacteria and their relevant genes in the wastewater of a municipal wastewater treatment plant has been evaluated. Two commonly used antibiotics, erythromycin and tetracycline were selected because of their wide occurrences in regard to the antibiotic resistance problem. After UV treatment at a fluence of 5mJcm(-2), the log reductions of heterotrophic bacteria resistant to erythromycin and tetracycline in the wastewater were found to be 1.4±0.1 and 1.1±0.1, respectively. The proportion of tetracycline-resistant bacteria (5%) was nearly double of that before UV disinfection (3%). Tetracycline-resistant bacteria exhibited more tolerance to UV irradiation compared to the erythromycin-resistant bacteria (p<0.05). Gene copy numbers were quantified via qPCR and normalized to the volume of original sample. The total concentrations of erythromycin- and tetracycline-resistance genes were (3.6±0.2)×10(5) and (2.5±0.1)×10(5) copies L(-1), respectively. UV treatment at a fluence of 5mJcm(-2) removed the total erythromycin- and tetracycline-resistance genes by 3.0±0.1 log and 1.9±0.1 log, respectively. UV treatment was effective in reducing antibiotic resistance in the wastewater. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Multi-component analysis of tetracyclines, sulfonamides and tylosin in swine manure by liquid chromatography-tandem mass spectrometry.

    PubMed

    Jacobsen, Anne Marie; Halling-Sørensen, Bent

    2006-03-01

    A multi-component method focussing on thorough sample preparation has been developed for simultaneous analysis of swine manure for three classes of antibiotic-tetracyclines, sulfonamides, and tylosin. Liquid manure was initially freeze-dried and homogenised by pulverization before extraction by pressurised liquid extraction. The extraction was performed at 75 degrees C and 2,500 psig in three steps using two cycles with 0.2 mol L(-1) citric acid buffer (pH 4.7) and one cycle with a mixture of 80% methanol with 0.2 mol L(-1) citric acid (pH 3). After liquid-liquid extraction with heptane to remove lipids, the pH of the manure was adjusted to 3 with formic acid and the sample was vacuum-filtered through 0.6 mum glass-fibre filters. Finally the samples were pre-concentrated by tandem SPE (SAX-HLB). Recoveries were determined for manure samples spiked at three concentrations (50-5,000 microg kg(-1) dry matter); quantification was achieved by matrix-matched calibration. Recoveries were >70% except for oxytetracycline (42-54%), sulfadiazine (59-73%), and tylosin (9-35%) and did not vary with concentration or from day-to-day. Limits of quantification (LOQ) for all compounds, determined as a signal-to-noise ratio of 10, were in the range 10-100 microg kg(-1) dry matter. The suitability of the method was assessed by analysis of swine manure samples from six different pig-production sites, e.g. finishing pigs, sows, or mixed production. Residues of antibiotics were detected in all samples. The largest amounts were found for tetracyclines (up to 30 mg kg(-1) dry matter for the sum of CTC and ECTC). Sulfonamides were detected at concentrations up to 2 mg kg(-1) dry matter (SDZ); tylosin was not detected in any samples.

  16. Characterization of the europium tetracycline complex as a biomarker for atherosclerosis

    NASA Astrophysics Data System (ADS)

    Courrol, Lilia C.; da Silva, Mônica N.; Sicchieri, Leticia B.

    2016-04-01

    Atherosclerosis is a narrowing of the arteries caused by an increase of atheromatous plaque: material formed by macrophage cells containing cholesterol and fatty acids, calcium and a variable amount of fibrous connective tissue. The elation between vulnerable plaques and cardiovascular events can be determined using plaque biomarkers. In this work, atherosclerotic plaques stained with different molar ratios of europium, in a potential plaque biomarker, europium tetracycline complex, were studied by fluorescence microscopy. The tetracycline antibiotic used was chlortetracycline. The growth of atherosclerotic plaque was followed during 60 days in New Zealand rabbits divided in two groups: an experimental group (EG), with nine animals and a control group (CG) with three animals. The animals in the EG received a diet with 1% of cholesterol and the animals of GC received a normal diet. The aortic arch of the animals with 60 days were cut in the vertical plane in 6 μm thick slices, which were mounted on glass slides and stained with hematoxylin an eosin and europium chlortetracycline complex (EuCTc). The fluorescence images were obtained exciting the EuCTc absorption band with a filter cube D (BP 355 - 425) and the emission was collected with a LP 470 suppression filter. Light intensity, detector gain and acquisition time were fixed for comparisons. The 20× magnified images were collected with 12 bit (or 4096 gray tones) resolution. The mean value of gray scale for each molar ratio of EuCTc was different, indicating that the complex interacts with the components of atherosclerotic plaque and the best molar ratio was 1.5 EuCTc. These results indicate the potential use of the EuCTc biomarker for atherosclerotic plaque characterization.

  17. Efficacy of oral azithromycin versus topical tetracycline in mass treatment of endemic trachoma.

    PubMed Central

    Fraser-Hurt, N.; Bailey, R. L.; Cousens, S.; Mabey, D.; Faal, H.; Mabey, D. C.

    2001-01-01

    OBJECTIVE: To compare the impact of mass treatment with oral azithromycin and topical tetracycline on the prevalence of active trachoma. METHODS: A total of 1803 inhabitants from 106 households of eight Gambian villages were randomized, in pairs, to receive either three doses of azithromycin at weekly intervals, or daily topical tetracycline over 6 weeks. Ocular examinations were conducted before treatment, and 2, 6 and 12 months after treatment. FINDINGS: Prior to treatment, 16% of the study participants had active trachoma. Two months after treatment, the prevalence of trachoma was 4.6% and 5.1% in the azithromycin and the tetracycline groups, respectively (adjusted odds ratio (OR) = 1.09; 95% confidence interval (CI) = 0.53, 2.02). Subsequently, the prevalence rose to 16% in the tetracycline group, while remaining at 7.7% in the azithromycin group (adjusted OR at 12 months = 0.52; 95% CI = 0.34, 0.80). At 12 months post-treatment, there were fewer new prevalent cases in the azithromycin group, and trachoma resolution was significantly better for this group (adjusted OR = 2.02; 95% CI = 1.42, 3.50). CONCLUSION: Oral azithromycin therefore appears to offer a means for controlling blinding trachoma. It is easy to administer and higher coverages may be possible than have been achieved hitherto. PMID:11477966

  18. Sclerotherapy for 'scrotal cysts' using tetracycline instillation.

    PubMed

    Courtney, S P; Wightman, J A

    1991-04-01

    Aspiration and tetracycline (Achromycin) instillation has been used to sclerose 'scrotal cysts'. Thirteen hydroceles and epididymal cysts were treated. Of the cysts treated, four failed to sclerose, and moderate to severe pain occurred in eight patients. In three patients the pain was severe, necessitating admission to the hospital. We would not recommend this treatment either in terms of efficacy or for patient comfort.

  19. Expression of Mitochondrial Cytochrome C Oxidase Chaperone Gene (COX20) Improves Tolerance to Weak Acid and Oxidative Stress during Yeast Fermentation

    PubMed Central

    Kumar, Vinod; Hart, Andrew J.; Keerthiraju, Ethiraju R.; Waldron, Paul R.; Tucker, Gregory A.; Greetham, Darren

    2015-01-01

    Introduction Saccharomyces cerevisiae is the micro-organism of choice for the conversion of fermentable sugars released by the pre-treatment of lignocellulosic material into bioethanol. Pre-treatment of lignocellulosic material releases acetic acid and previous work identified a cytochrome oxidase chaperone gene (COX20) which was significantly up-regulated in yeast cells in the presence of acetic acid. Results A Δcox20 strain was sensitive to the presence of acetic acid compared with the background strain. Overexpressing COX20 using a tetracycline-regulatable expression vector system in a Δcox20 strain, resulted in tolerance to the presence of acetic acid and tolerance could be ablated with addition of tetracycline. Assays also revealed that overexpression improved tolerance to the presence of hydrogen peroxide-induced oxidative stress. Conclusion This is a study which has utilised tetracycline-regulated protein expression in a fermentation system, which was characterised by improved (or enhanced) tolerance to acetic acid and oxidative stress. PMID:26427054

  20. Adsorption Properties of Tetracycline onto Graphene Oxide: Equilibrium, Kinetic and Thermodynamic Studies

    PubMed Central

    Ghadim, Ehsan Ezzatpour; Manouchehri, Firouzeh; Soleimani, Gholamreza; Hosseini, Hadi; Kimiagar, Salimeh; Nafisi, Shohreh

    2013-01-01

    Graphene oxide (GO) nanoparticle is a high potential effective absorbent. Tetracycline (TC) is a broad-spectrum antibiotic produced, indicated for use against many bacterial infections. In the present research, a systematic study of the adsorption and release process of tetracycline on GO was performed by varying pH, sorption time and temperature. The results of our studies showed that tetracycline strongly loads on the GO surface via π–π interaction and cation–π bonding. Investigation of TC adsorption kinetics showed that the equilibrium was reached within 15 min following the pseudo-second-order model with observed rate constants of k2 = 0.2742–0.5362 g/mg min (at different temperatures). The sorption data has interpreted by the Langmuir model with the maximum adsorption of 323 mg/g (298 K). The mean energy of adsorption was determined 1.83 kJ/mol (298 K) based on the Dubinin–Radushkevich (D–R) adsorption isotherm. Moreover, the thermodynamic parameters such as ΔH°, ΔS° and ΔG° values for the adsorption were estimated which indicated the endothermic and spontaneous nature of the sorption process. The electrochemistry approved an ideal reaction for the adsorption under electrodic process. Simulation of GO and TC was done by LAMMPS. Force studies in z direction showed that tetracycline comes close to GO sheet by C8 direction. Then it goes far and turns and again comes close from amine group to the GO sheet. PMID:24302989

  1. Adsorption properties of tetracycline onto graphene oxide: equilibrium, kinetic and thermodynamic studies.

    PubMed

    Ghadim, Ehsan Ezzatpour; Manouchehri, Firouzeh; Soleimani, Gholamreza; Hosseini, Hadi; Kimiagar, Salimeh; Nafisi, Shohreh

    2013-01-01

    Graphene oxide (GO) nanoparticle is a high potential effective absorbent. Tetracycline (TC) is a broad-spectrum antibiotic produced, indicated for use against many bacterial infections. In the present research, a systematic study of the adsorption and release process of tetracycline on GO was performed by varying pH, sorption time and temperature. The results of our studies showed that tetracycline strongly loads on the GO surface via π-π interaction and cation-π bonding. Investigation of TC adsorption kinetics showed that the equilibrium was reached within 15 min following the pseudo-second-order model with observed rate constants of k2 = 0.2742-0.5362 g/mg min (at different temperatures). The sorption data has interpreted by the Langmuir model with the maximum adsorption of 323 mg/g (298 K). The mean energy of adsorption was determined 1.83 kJ/mol (298 K) based on the Dubinin-Radushkevich (D-R) adsorption isotherm. Moreover, the thermodynamic parameters such as ΔH°, ΔS° and ΔG° values for the adsorption were estimated which indicated the endothermic and spontaneous nature of the sorption process. The electrochemistry approved an ideal reaction for the adsorption under electrodic process. Simulation of GO and TC was done by LAMMPS. Force studies in z direction showed that tetracycline comes close to GO sheet by C8 direction. Then it goes far and turns and again comes close from amine group to the GO sheet.

  2. Application of manure containing tetracyclines slowed down the dissipation of tet resistance genes and caused changes in the composition of soil bacteria.

    PubMed

    Xiong, Wenguang; Wang, Mei; Dai, Jinjun; Sun, Yongxue; Zeng, Zhenling

    2018-01-01

    Manure application contributes to the increased environmental burden of antibiotic resistance genes (ARGs). We investigated the response of tetracycline (tet) resistance genes and bacterial taxa to manure application amended with tetracyclines over two months. Representative tetracyclines (oxytetracycline, chlorotetracycline and doxycycline), tet resistance genes (tet(M), tet(O), tet(W), tet(S), tet(Q) and tet(X)) and bacterial taxa in the untreated soil, +manure, and +manure+tetracyclines groups were analyzed. The abundances of all tet resistance genes in the +manure group were significantly higher than those in the untreated soil group on day 1. The abundances of all tet resistance genes (except tet(Q) and tet(X)) were significantly lower in the +manure group than those in the +manure+tetracyclines group on day 30 and 60. The dissipation rates were higher in the +manure group than those in the +manure+tetracyclines group. Disturbance of soil bacterial community composition imposed by tetracyclines was also observed. The results indicated that tetracyclines slowed down the dissipation of tet resistance genes in arable soil after manure application. Application of manure amended with tetracyclines may provide a significant selective advantage for species affiliated to the taxonomical families of Micromonosporaceae, Propionibacteriaceae, Streptomycetaceae, Nitrospiraceae and Clostridiaceae. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. 21 CFR 520.2345e - Tetracycline oral liquid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2345e Tetracycline oral... animals which are raised for food production; Federal law restricts this drug to use by or on the order of a licensed veterinarian. (iv) National Academy of Sciences/National Research Council (NAS/NRC...

  4. 21 CFR 520.2345e - Tetracycline oral liquid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2345e Tetracycline oral... animals which are raised for food production; Federal law restricts this drug to use by or on the order of a licensed veterinarian. (iv) National Academy of Sciences/National Research Council (NAS/NRC...

  5. 21 CFR 520.2345e - Tetracycline oral liquid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2345e Tetracycline oral... animals which are raised for food production; Federal law restricts this drug to use by or on the order of a licensed veterinarian. (iv) National Academy of Sciences/National Research Council (NAS/NRC...

  6. UV light tolerance and reactivation potential of tetracycline-resistant bacteria from secondary effluents of a wastewater treatment plant.

    PubMed

    Huang, Jing-Jing; Xi, Jinying; Hu, Hong-Ying; Li, Yi; Lu, Sun-Qin; Tang, Fang; Pang, Yu-Chen

    2016-03-01

    Tetracycline-resistant bacteria (TRB) are of concern as emerging microbial contaminants in reclaimed water. To understand the effects of UV disinfection on TRB, both inactivation and reactivation profiles of TRB, as well as 16 tetracycline-resistant isolates from secondary effluent, were characterized in this study. The inactivation ratio of TRB was significantly lower (3.0-log) than that of heterotrophic bacteria (>4.0-log) in the secondary effluent. Additionally, the proportion of TRB significantly increased from 1.65% to 15.51% under 20mJ/cm(2) ultraviolet (UV) exposure. The inactivation rates of tetracycline-resistant isolates ranged from 0.57/s to 1.04/s, of which tetracycline-resistant Enterobacter-1 was the most tolerant to UV light. The reactivation of TRB, tetracycline-resistant isolated strains, as well as heterotrophic bacteria commonly occurred in the secondary effluent even after 20mJ/cm(2) UV exposure. The colony forming ability of TRB and heterotrophic bacteria reached 3.2-log and 3.0-log under 20mJ/cm(2) UV exposure after 22hr incubation. The final inactivation ratio of tetracycline-resistant Enterobacter-1 was 1.18-log under 20mJ/cm(2) UV exposure after 22hr incubation, which is similar to those of TRB (1.18-log) and heterotrophic bacteria (1.19-log). The increased proportion of TRB and the reactivation of tetracycline-resistant enterobacteria in reclaimed water could induce a microbial health risk during wastewater reuse. Copyright © 2015. Published by Elsevier B.V.

  7. Tetracycline treatment of type III prostatitis nanobacteria infection of 100 cases report

    NASA Astrophysics Data System (ADS)

    Guo, Junyi; Li, Chongxian; Wu, Baisuo; Hao, Shaojun; Ming, Aimin; Zhang, Xinji; Li, Wenjun; Zhang, Zhengchen

    2018-04-01

    To investigate the efficacy of tetracycline treatment of nanobacterial infection in 100 cases of type III prostatitis. randomly divided into treatment group and control group with double blind method, the treatment group was given Tetracycline Tablets 250mg, oral, 2 times a day; the control group were treated with Levofloxacin Tablets 0.lg, oral, 2 times a day; observation of curative effect of two groups of patients after 1 months of treatment. after the treatment group patients NIH-CPSI score and pain, urinary symptoms and quality of life scores were significantly lower than that of control group (P<0.01); after treatment, observation group lecithin corpuscle scale score was significantly higher than the control group (P<0.05). The treatment group and the control group patients after prostate fluid and cultured positive cases of nanobacterial numbers were 21 (21%) and 100 cases (100%), the positive rate of nanobacteria in observation group was significantly lower than the control group (P<0.05). There is a good effect Tetracycline Tablets treatment of nanobacterial infection of type III prostatitis.

  8. Sclerotherapy of idiopathic hydroceles and epididymal cysts: a historical comparison trial of 5% phenol versus tetracycline.

    PubMed

    East, J M; DuQuesnay, D

    2007-12-01

    Operating time for idiopathic hydroceles and epididymal cysts is scarce as these conditions compete with an increasing caseload of more consequential surgical disease. Therapy is often relegated to repeated aspiration. Sclerotherapy appears to be effective in a majority of published trials, but comparative effectiveness, efficacy and safety of most agents, including phenol versus tetracycline, has not been established A deliberate strategy of re-treatment until cure is not universally practised, with surgery still being offered after single-treatment failures. Two trials, the first consisting of 53 scrotal cysts treated with 5% phenol-in-water and the second, 42 cysts treated with tetracycline, are compared for effectiveness, efficacy and safety of sclerotherapy per se and of re-treatment. Intention-to-treat analysis yields similar cure rates (no re-accumulation three months after last injection) for phenol and tetracycline (83% and 81% respectively, p = 0.8). Per-protocol analysis also yields similar cure rates (100% and 97% respectively, p = 0.26) and mean number of injections to cure (1.34 and 1.12 respectively, p = 0.069), with range 1-4 and 1-3 respectively. Severe pain following tetracycline injection required administration of pre-injection cord block. Other complications occurred equally (25% and 25.7% respectively, p = 0.94) and were trivial except for one case of chronic haematocele treated by orchiectomy in the tetracycline group. Phenol (5%) and tetracycline are equally efficacious sclerosants for idiopathic scrotal cysts, achieving almost 100% cure with re-treatment and matching the efficacy of surgery. Concern about post-treatment fertility applies equally to surgery and demands informed consent for both modalities.

  9. Occurrence and diversity of tetracycline resistance genes in the agricultural soils of South Korea.

    PubMed

    Kim, Song Yeob; Kuppusamy, Saranya; Kim, Jang Hwan; Yoon, Young-Eun; Kim, Kwon-Rae; Lee, Yong Bok

    2016-11-01

    Reports on the occurrence and diversity of antibiotic-resistant bacteria and genes, which are considered to be emerging pollutants worldwide, have, to date, not been published on South Korean agricultural soils. This is the first study to investigate the persistence of tetracycline (oxytetracycline, tetracycline, and chlortetracycline)-resistant bacterial community and genes in natural and long-term fertilized (NPK, pig, and cattle manure composts) agricultural soils in South Korea. The results showed that oxytetracycline and chlortetracycline could be the dominant residues in animal manures; regular fertilization of manures, particularly pig manures, may be the prime cause for the spread and abundance of tetracycline resistance in South Korean agricultural soils. Both the country's natural and agricultural soils are reservoirs of antibiotic-resistant species. Of the 113 tetracycline-resistant isolates identified (19 typical bacterial genera and 36 distinct species), approximately 40 to 99 % belonged to Gram-positive bacteria and Bacillus constituted the predominant genera. Of the 24 tet genes targeted, tetG, tetH, tetK, tetY, tetO, tetS, tetW, and tetQ were detected in all soil samples, highlighting their predominance and robust adaptability in soils. Meanwhile, it is suggested that tetC, tetE, tetZ, tetM, tetT, and tetP(B) are the common residues in pig manures, and furthermore, the treatment of soils with pig manures may wield a different impact on the tet gene resistome in agricultural soils. This study thus highlights the necessity for regulating the usage of tetracyclines in South Korean animal farming. This must be followed by proper monitoring of the subsequent usage of animal manures especially that derived from pig farms located in agricultural soils.

  10. Rejection of Tetracycline and Oxytetracycline in Water by a Nanofiltration Membrane

    NASA Astrophysics Data System (ADS)

    Li, Weiying; Sun, Xiuli; Wang, Qing; Xu, Jingjing; Lu, Junyu

    2010-11-01

    The removal of tetracycline (TC) and oxytetracycline (OTC) by a nanofiltration (NF) membrane was studied using synthetic solutions. The effects of operation parameters (recovery and flux), feed concentration and salinity on the rejection of tetracyclines and their adsorption on membranes were investigated. TC was observed to show a high adsorptive affinity for the membrane. Almost 80% of TC and 70% of OTC were adsorbed on the membrane surface after stirring for 2000 min and over 50% of them had been adsorbed just 120 min after stir. High removal efficiencies (>90%) were observed for TC and OTC with NF membrane. Rejection ratio of OTC by NF was slightly higher than that of TC.

  11. Fluoroquinolone resistance of Serratia marcescens: sucrose, salicylate, temperature, and pH induction of phenotypic resistance.

    PubMed

    Begic, Sanela; Worobec, Elizabeth A

    2007-11-01

    Serratia marcescens is a nosocomial agent with a natural resistance to a broad spectrum of antibiotics, making the treatment of its infections very challenging. This study examines the influence of salicylate, sucrose, temperature, and pH variability on membrane permeability and susceptibility of S. marcescens to norfloxacin (hydrophilic fluoroquinolone) and nalidixic acid (hydrophobic quinolone). Resistance of wild-type S. marcescens UOC-67 (ATCC 13880) to norfloxacin and nalidixic acid was assessed by minimal inhibitory concentration (MIC) assays after growth in the presence of various concentrations of sucrose and salicylate and different temperatures and pH values. Norfloxacin and nalidixic acid accumulation was determined in the absence and presence of (i) carbonyl cyanide m-chlorophenylhydrazone (CCCP), a proton-motive-force collapser, and (ii) Phe-Arg beta-naphthylamide (PAbetaN), an efflux pump inhibitor. Accumulation of norfloxacin decreased when S. marcescens was grown in high concentrations of salicylate (8 mmol/L) and sucrose (10% m/v), at high temperature (42 degrees C), and at pH 6, and it was restored in the presence of CCCP because of the collapse of proton-gradient-dependent efflux in S. marcescens. Although nalidixic acid accumulation was observed, it was not affected by salicylate, sucrose, pH, or temperature changes. In the absence of PAbetaN, and either in the presence or absence of CCCP, a plateau was reached in the nalidixic acid accumulation for all environmental conditions. With the addition of 20 mg/L PAbetaN nalidixic acid accumulation is restored for all environmental conditions, suggesting that this quinolone is recognized by a yet to be identified S. marcescens pump that does not use proton motive force as its energy source.

  12. β-cyclodextrin-ionic liquid polymer based dynamically coating for simultaneous determination of tetracyclines by capillary electrophoresis.

    PubMed

    Zhou, Chunyan; Deng, Jingjing; Shi, Guoyue; Zhou, Tianshu

    2017-04-01

    Tetracyclines are a group of broad spectrum antibiotics widely used in animal husbandry to prevent and treat diseases. However, the improper use of tetracyclines may result in the presence of their residues in animal tissues or waste. Recently, great attention has been drawn towards the green solvents ionic liquids. Ionic liquids have been employed as a coating material to modify the electroosmotic flow in capillary electrophoresis. In this study, a functionalized ionic liquid, mono-6-deoxy-6-(3-methylimidazolium)-β-cyclodextrin tosylate, was synthesized and used for the simultaneous separation and quantification of tetracyclines by capillary electrophoresis. Good separation efficiency could be achieved due to the multiple functions of β-cyclodextrin derived ionic liquid, including the electrostatic interaction, the hydrogen bonding, and the cavity structure in β-cyclodextrin ionic liquid which can entrap the tetracyclines to form inclusion complex. After optimization, baseline separation achieved in 25 min with the running buffer consisted of 10 mmol/L, pH 7.2 phosphate buffer and 20 mmol/L β-cyclodextrin ionic liquid. The satisfied result demonstrated that the β-cyclodextrin ionic liquid is an ideal background electrolyte modifier in the separation of tetracyclines with high stability and good reproducibility. And it is an effective strategy to design and synthesize specific ILs as additive applied in separation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Surveillance of antimicrobial susceptibility patterns among Shigella species isolated in China during the 7-year period of 2005-2011.

    PubMed

    Yang, Haifei; Chen, Guosheng; Zhu, Yulin; Liu, Yanyan; Cheng, Jun; Hu, Lifen; Ye, Ying; Li, Jiabin

    2013-03-01

    Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with antibiotics is recommended for shigellosis, but the options are limited due to globally emerging resistance. This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella in China. We studied the antimicrobial resistance profiles of 308 Shigella spp. strains (260 S. flexneri, 40 S. sonnei, 5 S. boydii, and 3 S. dysenteriae) isolated from fecal samples of patients (age, from 3 months to 92 yr) presenting with diarrhea in different districts of Anhui, China. The antimicrobial resistance of strains was determined by the agar dilution method according to the CSLI guidelines. The most common serogroup in the Shigella isolates was S. flexneri (n=260, 84.4%), followed by S. sonnei (n=40, 13.0%). The highest resistance rate was found for nalidixic acid (96.4%), followed by ampicillin (93.2%), tetracycline (90.9%), and trimethoprim/sulfamethoxazole (80.8%). Among the isolates tested, 280 (91.0%) were multidrug resistant (resistant to ≥2 agents). The most common resistance pattern was the combination of ampicillin, tetracycline, and trimethoprim/sulfamethoxazole (70.8%). Resistance to ampicillin and tetracycline were more common among S. flexneri than among S. sonnei isolates. S. flexneri is predominant in Anhui, China, and its higher antimicrobial resistance rate compared with that of S. sonnei is a cause for concern. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in Shigella. The recommendations for antimicrobial treatment must be updated regularly based on surveillance results.

  14. Hog Charm II tetracycline test screening results compared with a liquid chromatography tandem mass spectrometry 10-μg/kg method.

    PubMed

    Salter, Robert; Holmes, Steven; Legg, David; Coble, Joel; George, Bruce

    2012-02-01

    Pork tissue samples that tested positive and negative by the Charm II tetracycline test screening method in the slaughter plant laboratory were tested with the modified AOAC International liquid chromatography tandem mass spectrometry (LC-MS-MS) method 995.09 to determine the predictive value of the screening method at detecting total tetracyclines at 10 μg/kg of tissue, in compliance with Russian import regulations. There were 218 presumptive-positive tetracycline samples of 4,195 randomly tested hogs. Of these screening test positive samples, 83% (182) were positive, >10 μg/kg by LC-MS-MS; 12.8% (28) were false violative, greater than limit of detection (LOD) but <10 μg/kg; and 4.2% (8) were not detected at the LC-MS-MS LOD. The 36 false-violative and not-detected samples represent 1% of the total samples screened. Twenty-seven of 30 randomly selected tetracycline screening negative samples tested below the LC-MS-MS LOD, and 3 samples tested <3 μg/kg chlortetracycline. Results indicate that the Charm II tetracycline test is effective at predicting hogs containing >10 μg/kg total tetracyclines in compliance with Russian import regulations.

  15. Comparison of the prevalences and antimicrobial resistances of Escherichia coli isolates from different retail meats in the United States, 2002 to 2008.

    PubMed

    Zhao, S; Blickenstaff, K; Bodeis-Jones, S; Gaines, S A; Tong, E; McDermott, P F

    2012-03-01

    Escherichia coli isolates were recovered from the National Antimicrobial Resistance Monitoring System retail meat program and examined for antimicrobial susceptibility. Retail meat samples (n = 11,921) from four U.S. states collected during 2002 to 2008, consisting of 2,988 chicken breast, 2,942 ground turkey, 2,991 ground beef, and 3,000 pork chop samples, were analyzed. A total of 8,286 E. coli isolates were recovered. The greatest numbers of samples contaminated with the organism were chicken (83.5%) and turkey (82.0%), followed by beef (68.9%) and pork (44.0%). Resistance was most common to tetracycline (50.3%), followed by streptomycin (34.6%), sulfamethoxazole-sulfisoxazole (31.6%), ampicillin (22.5%), gentamicin (18.6%), kanamycin (8.4%), amoxicillin-clavulanic acid (6.4%), and cefoxitin (5.2%). Less than 5% of the isolates had resistance to trimethoprim, ceftriaxone, ceftiofur, nalidixic acid, chloramphenicol, and ciprofloxacin. All isolates were susceptible to amikacin. Compared to beef and pork isolates, the poultry meat isolates had a greater percentage of resistance to all tested drugs, with the exception of chloramphenicol, to which pork isolates had the most resistance. More than half of the turkey isolates (56%) were resistant to multidrugs (≥3 classes) compared to 38.9% of chicken, 17.3% of pork, and 9.3% of beef isolates. The bla(CMY) gene was present in all ceftriaxone- and ceftiofur-resistant isolates. The cmlA, flo, and catI genes were present in 45%, 43%, and 40% of chloramphenicol-resistant isolates, respectively. Most nalidixic acid-resistant isolates (98.5%) had a gyrA mutation in S83 or D87 or both, whereas only 6.7% had a parC mutation in either S80 or E84. The results showed that E. coli was commonly present in the retail meats, and antimicrobial resistance profiles differed according to the animal origin of the isolates.

  16. Antibiotic resistance and growth of the emergent pathogen Escherichia albertii on raw ground beef stored under refrigeration, abuse, and physiological temperature.

    PubMed

    Perez, Keila L; Alam, M Jahangir; Castillo, Alejandro; Taylor, T Matthew

    2013-01-01

    Escherichia albertii is an emerging gram-negative facultative rod that has been implicated in multiple cases of human diarrheal disease, particularly in young children. When biochemical and other typing methods have been used, this organism has often been misidentified due to similarities with other members of the family Enterobacteriaceae. Isolates have been reported to be capable of producing attachment and effacement lesions via the synthesis of intimin, cytolethal distending toxin, and a variant form of Shiga toxin. The purposes of this study were to characterize the antibiotic resistance characteristics and the growth of individual strains of E. albertii on raw ground beef at different storage temperatures. Nalidixic acid-resistant strains of E. albertii were inoculated onto raw ground beef to a target of 4.0 log CFU/g, and samples were then aerobically incubated at 5, 22, or 35°C for various time periods prior to microbiological enumeration of the pathogen on lactose-free MacConkey agar containing 50 mg of nalidixic acid per liter and 0.5% L-rhamnose. Antibiotic resistance was determined using a broth microdilution assay. E. albertii did not grow at 5°C, with populations declining slowly over 14 days of refrigerated storage. Strains of the organism grew well under abusive storage, increasing by 2.5 to 3.1 log CFU/g and 4.1 to 4.3 log CFU/g after 24 h at 22 and 35°C, respectively. All strains were resistant to tetracycline but were sensitive to tested cephalosporins and chloramphenicol. Resistance to penicillin was observed, but susceptibility to other members of the b -lactam group, including ampicillin, amoxicillin, and clavulanic acid, was recorded. E. albertii represents an emerging pathogen with a probable foodborne transmission route. Future research should focus on verifying food process measures able to inactivate the pathogen.

  17. Towards early detection of age-related macular degeneration with tetracyclines and FLIM

    NASA Astrophysics Data System (ADS)

    Szmacinski, Henryk; Hegde, Kavita; Zeng, Hui-Hui; Eslami, Katayoun; Puche, Adam; Lakowicz, Joseph R.; Lengyel, Imre; Thompson, Richard B.

    2018-02-01

    Recently, we discovered microscopic spherules of hydroxyapatite (HAP) in aged human sub-retinal pigment epithelial (sub-RPE) deposits in the retinas of aged humans (PMID: 25605911), and developed evidence that the spherules may act to nucleate the growth of sub-RPE deposits such as drusen. Drusen are clinical hallmarks of age-related macular degeneration (AMD). We found that tetracycline-family antibiotics, long known to stain HAP in teeth and bones, also stained the HAP spherules, but in general the HAP-bound fluorescence excitation and emission spectra overlapped with the well-known autofluorescence of the RPE overlying drusen, making them difficult to resolve. However, we also found that certain tetracyclines exhibited substantial increases in fluorescence lifetime upon binding to HAP, and moreover these lifetimes were substantially greater than those previously observed (Dysli, et al., 2014) for autofluorescence in the human retina in vivo. Thus we were able to image the HAP spherules by fluorescence lifetime imaging microscopy (FLIM) in cadaveric retinas of aged humans. These findings suggest that FLIM imaging of tetracycline binding to HAP could become a diagnostic tool for the development and progression of AMD.

  18. Temporal dynamics of periphyton exposed to tetracycline in stream mesocosms

    EPA Science Inventory

    Significant amounts of antibiotics enter the environment via point and non-point sources. We examined the temporal dynamics of tetracycline exposure to stream periphyton and associated organisms across a logarithmically dosed series of experimental mesocosms, designed to mimic na...

  19. Electrophoretic deposition of tetracycline modified silk fibroin coatings for functionalization of titanium surfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Zhen; Qu, Yinying; Li, Xiaoshuang; Zhang, Sheng; Wei, Qingsong; Shi, Yusheng; Chen, Lili

    2014-06-01

    Electrophoretic deposition has been widely used for the fabrication of functional coatings onto metal implant. A characteristic feature of this process is that positively charged materials migrate toward the cathode and can deposit on it. In this study, silk fibroin was decorated with tetracycline in aqueous solution to impart positive charge, and then deposited on negatively titanium cathode under certain electric field. The characterization of the obtained coatings indicated that the intermolecular hydrogen bonds formed between the backbone of silk fibroin and tetracycline molecular. In vitro biological tests demonstrated that osteoblast-like cells achieved acceptable cell affinity on the tetracycline cross-linked silk fibroin coatings, although greater cell viability was seen on pure silk fibroin coatings. The cationic silk fibroin coatings showed remarkable antibacterial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. Therefore, we concluded that electrophoretic deposition was an effective and efficient technique to prepare cationic silk fibroin coatings on the titanium surface and that cationic silk fibroin coatings with acceptable biocompatibility and antibacterial property were promising candidates for further loading of functional agents.

  20. Self-sensitization of tetracycline degradation with simulated solar light catalyzed by ZnO@montmorillonite

    NASA Astrophysics Data System (ADS)

    Zyoud, Ahed; Jondi, Waheed; AlDaqqah, Najat; Asaad, Sara; Qamhieh, Naser; Hajamohideen, AbdulRazack; Helal, Muath H. S.; Kwon, Hansang; Hilal, Hikmat S.

    2017-12-01

    Zinc oxide (ZnO) nano-particles were chemically deposited onto montmorillonite (MONT) clay particles. The composite ZnO@MONT was then characterized and used as a catalyst for photo-degradation of aqueous tetracycline. Unlike earlier studies, solar simulated light can be effectively used in this work. The composite shows high efficiency as adsorbent and as a photo-degradation catalyst. Both adsorbed and dissolved tetracycline molecules undergo mineralization under the photo-catalytic conditions, and up to 94% of the contaminant gross amount is completely mineralized. Other forms of ZnO particles, commercial ZnO and synthetic ZnO particles were examined in separate experiments. The ZnO@MONT is superior to both pristine counterparts. The ability of tetracycline to sensitize the supported ZnO particles, to solar simulated light, before being photo-degraded itself, is discussed here for the first time. In addition to enhanced catalytic activity of the ZnO@MONT, the composite can be efficiently recovered and reused with no significant loss of efficiency.

  1. Prevalence and Diversity of Salmonella Serotypes in Ecuadorian Broilers at Slaughter Age

    PubMed Central

    Cevallos, María; Ron-Garrido, Lenin; Bertrand, Sophie; De Zutter, Lieven

    2016-01-01

    Salmonella is frequently found in poultry and represent an important source for human gastrointestinal infections worldwide. The aim of this study was to investigate the prevalence, genotypes and antimicrobial resistance of Salmonella serotypes in broilers from Ecuador. Caeca content from 388 at random selected broiler batches were collected in 6 slaughterhouses during 1 year and analyzed by the ISO 6579/Amd1 protocol for the isolation for Salmonella. Isolates were serotyped and genotypic variation was acceded by pulsed field gel electrophoresis. MIC values for sulfamethoxazole, gentamicin, ciprofloxacin, ampicillin, cefotaxime, ceftazidime, tetracycline, streptomycin, trimethropim, chloramphenicol, colistin, florfenicol, kanamycin and nalidixic acid were obtained. Presence of blaCTX-M, blaTEM, blaSHV and blaCMY; and mcr-1 plasmid genes was investigated in resistant strains to cefotaxime and colistin respectively. Prevalence at batch level was 16.0%. The most common serotype was S. Infantis (83.9%) followed by S. Enteritidis (14.5%) and S. Corvallis (1.6%). The pulsed field gel electrophoresis analysis showed that S. Corvallis, S. Enteritidis and S. Infantis isolates belonged to 1, 2 and 12 genotypes respectively. S. Infantis isolates showed high resistance rates to 12 antibiotics ranging from 57.7% (kanamycin) up to 98.1% (nalidixic acid and sulfamethoxazole). All S. Enteritidis isolates showed resistance to colistin. High multiresistant patterns were found for all the serotypes. The blaCTX-M gene was present in 33 S. Infantis isolates while mcr-1 was negative in 10 colistin resistant isolates. This study provides the first set of scientific data on prevalence and multidrug-resistant Salmonella coming from commercial poultry in Ecuador. PMID:27414038

  2. Aspiration and tetracycline sclerotherapy of hydroceles.

    PubMed

    Levine, L A; DeWolf, W C

    1988-05-01

    Aspiration and sclerotherapy of hydroceles have been considered an effective outpatient procedure. We report on our experience with modification of this procedure in the treatment of 28 hydroceles. A 10 per cent solution of tetracycline hydrochloride was used as the sclerosant. In this series the mean followup was 15 months and there was an over-all 93 per cent success rate. A single treatment was successful in 75 per cent of the hydroceles. Complications included a hematoma in 2 patients and epididymitis in 1. We consider aspiration and sclerotherapy of hydroceles to be a reasonable alternative to an operation.

  3. Screening method for the determination of tetracyclines and fluoroquinolones in animal drinking water by liquid chromatography with diode array detector.

    PubMed

    Patyra, E; Kowalczyk, E; Grelik, A; Przeniosło-Siwczyńska, M; Kwiatek, K

    2015-01-01

    A liquid chromatography - diode array detector (HPLC-DAD) procedure has been developed for the determination of oxytetracycline (OTC), tetracycline (TC), chlorotetracycline (CTC), doxycycline (DC), enrofloxacin (ENR), ciprofloxacin (CIP), sarafloxacin (SAR) and flumequine (FLU) residues in animal drinking water. This method was applied to animal drinking water. Solid-phase extraction (SPE) clean-up on an Oasis HLB cartridge allowed an extract suitable for liquid chromatographic analysis to be obtained. Chromatographic separation was carried out on a C18 analytical column, using gradient elution with 0.1% trifluoroacetic acid - acetonitrile - methanol at 30°C. The flow-rate was 0.7 mL/min and the eluate was analysed at 330 nm. The whole procedure was evaluated according to the requirements of the Commission Decision 2002/657/EC, determining specificity, decision limit (CCα), detection capacity (CCβ), limit of detection (LOD), limit of quantification (LOQ), precision and accuracy during validation of the method. The recoveries of TCs and FQs from spiked samples at the levels of 10, 100 and 1000 μg/L were higher than 82%. The developed method based on HPLC-DAD has been applied for the determination of four tetracyclines and four fluoroquinolones in animal drinking water samples.

  4. Removal of antibiotics in wastewater: Effect of hydraulic and solid retention times on the fate of tetracycline in the activated sludge process.

    PubMed

    Kim, Sungpyo; Eichhorn, Peter; Jensen, James N; Weber, A Scott; Aga, Diana S

    2005-08-01

    A study was conducted to examine the influence of hydraulic retention time (HRT) and solid retention time (SRT) on the removal of tetracycline in the activated sludge processes. Two lab-scale sequencing batch reactors (SBRs) were operated to simulate the activated sludge process. One SBR was spiked with 250 microg/L tetracycline, while the other SBR was evaluated at tetracycline concentrations found in the influent of the wastewater treatment plant (WWTP) where the activated sludge was obtained. The concentrations of tetracyclines in the influent of the WWTP ranged from 0.1 to 0.6 microg/L. Three different operating conditions were applied during the study (phase 1-HRT: 24 h and SRT: 10 days; phase 2-HRT: 7.4 h and SRT: 10 days; and phase 3-HRT: 7.4 h and SRT: 3 days). The removal efficiency of tetracycline in phase 3 (78.4 +/- 7.1%) was significantly lower than that observed in phase 1 (86.4 +/- 8.7%) and phase 2 (85.1 +/- 5.4%) at the 95% confidence level. The reduction of SRT in phase 3 while maintaining a constant HRT decreased tetracycline removal efficiency. Sorption kinetics reached equilibrium within 24 h. Batch equilibrium experiments yielded an adsorption coefficient (Kads) of 8400 +/- 500 mL/g and a desorption coefficient (Kdes) of 22 600 +/- 2200 mL/g. No evidence of biodegradation for tetracycline was observed during the biodegradability test, and sorption was found to be the principal removal mechanism of tetracycline in activated sludge.

  5. Treatment of hydroceles by aspirations and tetracycline instillations.

    PubMed

    Suwan, P

    1994-08-01

    In conclusion, tetracycline hydrochloride is an effective and safe sclerosant for the treatment of hydrocele with entailing minimal side effects and low recurrence rate. However, it should not be recommended for the treatment of spermatocele in younger men who still wish to have children, because of the danger of drug epididymitis and resulting infertility. Hydrocele treatment can be performed in younger men who still wish to have children.

  6. [Antibiotic resistance to erythromycin, clindamycin and tetracycline of 573 strains of Streptococcus pyogenes (1992-1994)].

    PubMed

    Orden, B; Martínez, R; López de los Mozos, A; Franco, A

    1996-02-01

    The aim of this study was to know the antibiotic resistence of Streptococcus pyogenes to erythromycine, clindamycine and/or tetracycline in community samples. The second aim was to determine the existence of multiresistant strains and to know the relationship between resistant strains, clinical samples and age of the patient. A retrospective analysis was performed in all the strains of S. pyogenes isolated from January 1992 to December 1994. Antibiotic sensitivity was studied by MIC by the microdilution method using the Pasco semiautomatic system. During the study period 573 beta hemolytic streptococci were identified as S. pyogenes. The global resistance to erythromycine (2.8%), clindamycine (1.4%) and tetracycline (7.3%) remains at low levels but has significantly increased in the case of erythromycine (p < 0.05) and tetracycline (p < 0.05) over these 3 years. The incidence of strains resistant to clindamycine has also increased slowly although this rise is not significant. Five strains (0.9%) were not sensitive to the three antibiotics studied, 4 being isolated in the last trimester of 1994 in pharyngeal exudates. S. pyogenes resistant to erythromycine was most frequently isolated from cutaneous lesions and in pediatric patients (under the age of 14 years). These results confirm the trend towards an increase in the number of strains of S. pyogenes resistant to erythromycine, clindamycine and/or tetracycline, being most often found in cutaneous lesions and pediatric patients.

  7. Characterization of a clinical Vibrio cholerae O139 isolate from Mexico.

    PubMed

    Parveen, Salina; Farrah, Samuel R; Gonzalez-Bonilla, Celia; Zamudio, Altagracia V; Tamplin, Mark L

    2003-01-01

    Pathogenic strains of Vibrio cholerae O139 possess the cholera toxin A subunit (ctxA) gene as well as the gene for toxin co-regulated pili (tcpA). We report the isolation of a ctxA-negative, tcpA-negative V. cholerae O139 strain (INDREI) from a patient in Mexico diagnosed with gastrointestinal illness. Certain phenotypic characteristics of this strain were identical to those of V. cholerae O1 biotype El Tor. Unlike ctxA-positive V. cholerae O139 strains, this strain was sensitive to a wide panel of antibiotics, including ampicillin, chloramphenicol, ciprofloxacin, gentamicin, furazolidone, nalidixic acid, nitrofurantoin, tetracycline, trimethoprim-sulfamethoxazole, and streptomycin, but was resistant to polymyxin B. Ribotype and pulsed-field gel electrophoresis profiles of INDRE1 differed from those of ctxA-positive V. cholerae O139 and other V. cholerae strains. Phenotypic characteristics of the Mexico strain were similar to those reported for V. cholerae O139 isolates from Argentina and Sri Lanka.

  8. Antimicrobial-resistant Klebsiella species isolated from free-range chicken samples in an informal settlement.

    PubMed

    Fielding, Burtram C; Mnabisa, Amanda; Gouws, Pieter A; Morris, Thureyah

    2012-02-29

    Sub-therapeutic doses of antimicrobial agents are administered routinely to poultry to aid growth and to prevent disease, with prolonged exposure often resulting in bacterial resistance. Crossover of antibiotic resistant bacteria from poultry to humans poses a risk to human health. In this study, 17 chicken samples collected from a vendor operating in an informal settlement in the Cape Town Metropolitan area, South Africa were screened for antimicrobial-resistant Gram-negative bacilli using the Kirby Bauer disk diffusion assay. IN TOTAL, SIX ANTIBIOTICS WERE SCREENED: ampicillin, ciprofloxacin, gentamicin, nalidixic acid, tetracycline and trimethoprim. Surprisingly, Klebsiella ozaenae was identified in 96 and K. rhinoscleromatis in 6 (n=102) of the samples tested. Interestingly, ∼40% of the isolated Klebsiella spp. showed multiple resistance to at least three of the six antibiotics tested. Klebsiella ozaenae and K. rhinoscleromatis cause clinical chronic rhinitis and are almost exclusively associated with people living in areas of poor hygiene.

  9. Occurrence of enteric redmouth disease in rainbow trout (Oncorhynchus mykiss) on farms in Croatia.

    PubMed

    Oraić, D; Zrncić, Snjezana; Sostarić, B; Bazulić, D; Lipej, Z

    2002-01-01

    During the spring of 1996 and autumn of 1997 unusual mortality outbreaks among rainbow trout fry and yearlings occurred at two different trout farms, resulting in mortality of 20 and 10 per cent, respectively. Generally, the affected fish, swimming at the water surface, were reluctant to eat and were dark pigmented with visible haemorrhages around and within the oral cavity. Bacterial isolates from moribund fish from both cases were identified as Yersinia ruckeri by standard biochemical tests and API 20E. The isolated strains were found to be sensitive to tetracycline, chloramphenicol, co-trimoxazole, nalidixic acid, flumequine, enrofloxacin, carbenicillin and gentamicin. Microplate agglutination assay confirmed that both isolates belonged to serotype O1. The pathogenicity of the isolated bacteria was confirmed by challenge experiment. Titres of specific antibodies were determined in the sera of survivors. The titre was highest on the 21st day postchallenge and was detectable until the 81st day.

  10. Chemical, microbial and antibiotic susceptibility analyses of groundwater after a major flood event in Chennai

    PubMed Central

    Gowrisankar, Ganesan; Chelliah, Ramachandran; Ramakrishnan, Sudha Rani; Elumalai, Vetrimurugan; Dhanamadhavan, Saravanan; Brindha, Karthikeyan; Antony, Usha; Elango, Lakshmanan

    2017-01-01

    During floods, human exposure to pathogens through contaminated water leads to the outbreak of epidemic diseases. This research presents the first extensive assessment of surface and groundwater samples collected immediately after a flood (December 2015) and post-flood (April 2016) from the Adyar River of Chennai, a major city in India, for major ions, trace metals, bacterial population, and pathogens. Severe rains in a short period of time resulted in flooding which inundated the wells, allowing the entry of sewage contaminated river water into the groundwater zone. This has led to bacterial counts and chemical ions exceeding Bureau of Indian Standard’s recommended limits in most flood affected areas. Pathogens isolated from the groundwater showed resistance to antibiotics, namely ceftriaxone, doxycycline and nalidixic acid. However, they were sensitive to chloramphenicol, ciprofloxacin, norfloxacin, and tetracycline. Determining the antibiotic susceptibility of pathogens will help in the treatment of humans affected by contaminated water through an appropriate selection of prescribed medication. PMID:28994821

  11. Healing Potentials of Oral Moringa Oleifera Leaves Extract and Tetracycline on Methicillin Resistant Staphylococcus Aureus Infected Wounds of Wistar rats.

    PubMed

    Eyarefe, Oghenemega D; Idowu, Aderayo; Afolabi, Jeremiah M

    2015-12-20

    The effects of oral dose of aqueous extract of Moringa oleifera and tetracycline antibiotics on cutaneous wounds infected with Staphylococcus aureus were studied in eighteen adult wistar rats (159±31.5g) randomized into three groups: Group A, n = 6, Moringa oleifera-(300 mg/kg). Group B, n = 6, tetracycline (9.4 mg/kg) and Group C, n = 6, Sterile water (control). Six millimetres diameter nape wound, created on each rat under 2% xylazine (5 mg/kg) and 5% ketamine (35 mg/kg), was contaminated with Staphylococcus aureus (108 Colony Forming Unit (CFU). Following infection, treatment was commenced with daily oral dose of test preparations and the wounds were evaluated every other day i.e., day 3, 5, 7, 9, 11, 13 and 15 for wetness (wound exudation), wound edge oedema, hyperaemia, granulation tissues and contraction (diameter). Severe wound exudation existed in all the groups between days 0-3 (p = 1.00). A significantly less wound exudation was observed at days 3-5 (p = 0.000) and 5-9 (p = 0.003) (Control< Tetracycline Tetracycline). Hyperaemia was pronounced in all the groups from days 0-3, but became significantly less (p<0.05) at days 5-7 (p = 0.002) and 9-15 (p = 0.001) (ControlTetracycline). A significantly more wound granulation tissue was observed among the groups at days 5-9 (p = 0.002) and 9-15 (p = 0.001) (Control> Moringa> Tetracycline). Differences in wound diameter was not significant except at days 5-9 (p = 0.013) (Control> Moringa >Tetracycline). Oral doses of Moringa oleifera extract (300mg/kg) and tetracycline (9.4mg/kg) are not effective as antimicrobial or immune-boosting agents to enhance healing of wounds infected with Staphylococcus aureus and hence not recommended for rapid clearance of Staphylococcus aureus infected wounds.

  12. A Scanning Electron Microscope Evaluation of Smear Layer Removal and Antimicrobial Action of Mixture of Tetracycline, Acid and Detergent, Sodium Hypochlorite, Ethylenediaminetetraacetic Acid, and Chlorhexidine Gluconate: An In vitro Study.

    PubMed

    Charlie, K M; Kuttappa, M A; George, Liza; Manoj, K V; Joseph, Bobby; John, Nishin K

    2018-01-01

    The main objective is to evaluate the efficiency in removal of smear layer of mixture of tetracycline, acid and detergent (MTAD), sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA) and chlorhexidine gluconate by scanning electron microscope (SEM) evaluation and also to evaluate the antimicrobial action of the same irrigants against standard culture strains of Enterococcus faecalis . This study included 60 extracted permanent teeth with single root canal. The sample was categorized into five groups with 12 teeth in each group. Root canals were enlarged till size 40 with K-files. One group was kept as control and irrigated only with saline. Other four groups used 5% NaOCl as irrigant during instrumentation and MTAD, 5% NaOCl, 17% EDTA, and 2% chlorhexidine gluconate as final rinse. Teeth were split and examined under SEM. To test the antibacterial action, the zone of inhibition method using agar plates was used. Obtained data were statistically analyzed by SPSS version 17 (SPSS Inc., Chicago, IL, USA). MTAD and 17% EDTA removed smear layer from all regions of the root canals. About 5% NaOCl and 2% chlorhexidine gluconate were ineffective in removing the smear layer. The mean zone of inhibition formed by the irrigants was in the following order; MTAD (40.5 mm), 2% chlorhexidine gluconate (29.375 mm), 17% EDTA (24.125 mm), 5% NaOCl (22.125 mm), and saline (zero). MTAD showed high smear layer removal efficacy, but no significant difference was found to that of 17% EDTA. As the dimensions of the zones of inhibition showed, MTAD has got highest antibacterial action against E. faecalis , followed by 2% chlorhexidine gluconate, 17% EDTA, and 5% NaOCl. However, the exact correlation of in vitro study results to clinical conditions is impossible due to the variables involved.

  13. Assessment of oxytetracycline and tetracycline antibiotics in manure samples in different cities of Khuzestan Province, Iran.

    PubMed

    Alavi, Nadali; Babaei, Ali Akbar; Shirmardi, Mohammad; Naimabadi, Abolfazl; Goudarzi, Gholamreza

    2015-11-01

    Tetracyclines (TCs), a class of antibiotics with a broad spectrum, are the most frequently used antibiotics in animal production. The major concern is that the widespread use of the antibiotics may lead to the emergence of new strains of bacteria that are resistant to these antibiotics. The objective of this study was to determine the residual levels of oxytetracycline and tetracycline in 80 animal manure samples that were collected from the livestock and poultry feedlots in Khuzestan Province. The residual levels of the antibiotics in the samples were extracted by using solid-phase extraction (SPE) method and subsequently were measured by liquid chromatography. Recoveries from the spiked poultry manure samples ranged from 65 to 113% for tetracycline and 86 to 132% for oxytetracycline. Relative standard deviations of the recoveries were less than 5.7% within the same day. Method detection limit (MDL) measured for oxytetracycline and tetracycline in the manure were 0.011 and 0.01 mg/kg, respectively. Analysis of the collected 50 chickens and 30 cow manure samples showed that the highest concentration of tetracycline was related to Behbahan City (5.36 mg/kg) and the lowest concentration was detected for Ramhormoz (0.05 mg/kg). The highest and lowest concentrations of oxytetracycline were respectively observed for Behbahan (13.77 mg/kg) and Ramhormoz (0.047 mg/kg). Based on the results, in chicken manure, there was significant statistical difference between the residual TC concentrations among five cities (p(value) < 0.05). However, no significant relationship was observed between oxytetracyclin (OTC) residual concentrations among five cities (p(value) > 0.05).

  14. Antimicrobial Resistance of Campylobacter Isolates from Retail Meat in the United States between 2002 and 2007▿

    PubMed Central

    Zhao, S.; Young, S. R.; Tong, E.; Abbott, J. W.; Womack, N.; Friedman, S. L.; McDermott, P. F.

    2010-01-01

    The emergence of antimicrobial resistance in Campylobacter spp. has been a growing public health concern globally. The objectives of this study were to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Campylobacter spp. recovered by the National Antimicrobial Resistance Monitoring System (NARMS) retail meat program. Retail meat samples (n = 24,566) from 10 U.S. states collected between 2002 and 2007, consisting of 6,138 chicken breast, 6,109 ground turkey, 6,171 ground beef, and 6,148 pork chop samples, were analyzed. A total of 2,258 Campylobacter jejuni, 925 Campylobacter coli, and 7 Campylobacter lari isolates were identified. Chicken breast samples showed the highest contamination rate (49.9%), followed by ground turkey (1.6%), whereas both pork chops and ground beef had <0.5% contamination. The most common resistance was to doxycycline/tetracycline (46.6%), followed by nalidixic acid (18.5%), ciprofloxacin (17.4%), azithromycin and erythromycin (2.8%), telithromycin (2.4%), clindamycin (2.2%), and gentamicin (<0.1%). In a subset of isolates tested, no resistance to meropenem and florfenicol was seen. C. coli isolates showed higher resistance rates to antimicrobials, with the exception of doxycycline/tetracycline, than those seen for C. jejuni. Pulsed-field gel electrophoresis (PFGE) fingerprinting resulted in 1,226 PFGE profiles among the 2,318 isolates, with many clones being widely dispersed throughout the 6-year sampling period. PMID:20971875

  15. Antimicrobial resistance of Campylobacter isolates from retail meat in the United States between 2002 and 2007.

    PubMed

    Zhao, S; Young, S R; Tong, E; Abbott, J W; Womack, N; Friedman, S L; McDermott, P F

    2010-12-01

    The emergence of antimicrobial resistance in Campylobacter spp. has been a growing public health concern globally. The objectives of this study were to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Campylobacter spp. recovered by the National Antimicrobial Resistance Monitoring System (NARMS) retail meat program. Retail meat samples (n = 24,566) from 10 U.S. states collected between 2002 and 2007, consisting of 6,138 chicken breast, 6,109 ground turkey, 6,171 ground beef, and 6,148 pork chop samples, were analyzed. A total of 2,258 Campylobacter jejuni, 925 Campylobacter coli, and 7 Campylobacter lari isolates were identified. Chicken breast samples showed the highest contamination rate (49.9%), followed by ground turkey (1.6%), whereas both pork chops and ground beef had <0.5% contamination. The most common resistance was to doxycycline/tetracycline (46.6%), followed by nalidixic acid (18.5%), ciprofloxacin (17.4%), azithromycin and erythromycin (2.8%), telithromycin (2.4%), clindamycin (2.2%), and gentamicin (<0.1%). In a subset of isolates tested, no resistance to meropenem and florfenicol was seen. C. coli isolates showed higher resistance rates to antimicrobials, with the exception of doxycycline/tetracycline, than those seen for C. jejuni. Pulsed-field gel electrophoresis (PFGE) fingerprinting resulted in 1,226 PFGE profiles among the 2,318 isolates, with many clones being widely dispersed throughout the 6-year sampling period.

  16. Presence and characterization of Campylobacter jejuni in organically raised chickens in Quebec

    PubMed Central

    Thibodeau, Alexandre; Fravalo, Philippe; Laurent-Lewandowski, Sylvette; Guévremont, Evelyne; Quessy, Sylvain; Letellier, Ann

    2011-01-01

    The objective of this study was to estimate the presence of the important foodborne pathogen Campylobacter jejuni in organically raised chickens in the province of Quebec. The recovered isolates were further characterized for their antimicrobial resistance profile, autoagglutination property and chemotaxis. Antimicrobial resistance was evaluated using agar dilution for: tetracycline, erythromycin, chloramphenicol, ciprofloxacin, gentamicin, nalidixic acid, clindamycin, ampicillin, azithromycin, bacitracin, and ceftiofur. Autoagglutination was measured by monitoring optical density changes in a bacterial suspension after 3 h of incubation at room temperature. Chemotaxis was evaluated after a contact time of 3 h between isolates and mucin, using a quantitative protocol. A total of 10 lots of chickens was sampled in August and September 2009; half of them were positive for the presence of C. jejuni. Antimicrobial resistance was found only for tetracycline (44%), erythromycin (6%), azithromycin (6%) and clindamycin (2%). Variation was observed in the minimum inhibitory concentrations (MICs) for ceftiofur and bacitracin, for which C. jejuni possess intrinsic resistance. Autoagglutination and chemotaxis varied among isolates and lot-level differences in these were observed. Autoagglutination and chemotaxis levels appeared as independent isolate properties. Further monitoring and characterization of isolates originating from organic chickens is of interest since this type of production might represent another source of exposure of consumers to a variety of the foodborne pathogen C. jejuni. PMID:22468028

  17. Anti-microbial resistance stratified by risk factor among Escherichia coli strains isolated from the urinary tract at a rural clinic in Central India.

    PubMed

    Chatterjee, B; Kulathinal, S; Bhargava, A; Jain, Y; Kataria, R

    2009-01-01

    The failure of empirical therapy is frequently observed, even in community-acquired urinary tract infections. We, therefore, conducted a prospective, clinic-based study in 2004-2005 to document anti-microbial resistance rates and correlate them with possible risk factors to assist empirical decision-making. Symptomatic patients with pyuria underwent urine culture. Isolates were identified using standard methods and anti-microbial resistance was determined by disk-diffusion. Ultrasonography was used to detect complicating factors. Patients were stratified by the presence of complicating factors and history of invasive procedures for comparison of resistance rates. STATISTICAL METHOD USED: Chi-square or Fisher exact tests, as appropriate. There were 156 E. coli isolates, of which 105 were community-acquired. Twenty-three community-acquired isolates were from patients with complicating factors while 82 were from patients without any. Fifty-one isolates were from patients who had recently undergone invasive procedures on the urinary tract. Thirty-two community-acquired isolates from reproductive-age women without apparent complicating factors had resistance rates of 50% or above against tetracyclines, Co-trimoxazole, aminopenicillins, Nalidixic acid, Ciprofloxacin and 1 st generation cephalosporins. Resistance rates were significantly higher among isolates from patients subjected to invasive procedures, except against Co-trimoxazole, tetracyclines and Amikacin. High rates of anti-microbial resistance in community-acquired uropathogens have made antimicrobial sensitivity testing necessary even in a rural, primary-care setting.

  18. Severe tetracycline dental discoloration: Restoration with conventional feldspathic ceramic veneers. A clinical report.

    PubMed

    Faus-Matoses, Vicente; Faus-Matoses, Ignacio; Ruiz-Bell, Esther; Faus-Llácer, Vicente J

    2017-11-01

    The treatment of severe tetracycline discoloration is a challenge for the dentist. There are several treatment options and one of the most effective is the use of feldspathic veneers. The aim of this clinical case was to carry out the replacement with conventional feldspathic ceramic veneers on a patient with highly stained teeth (grade IV tetracycline) by a minimally invasive approach. Clinical examination revealed gingival retraction, color change of the veneers, ceramic cracked of 1.1 and 1.3 and incisal wear in lower anterior teeth. The decision was to retreat with feldspathic ceramic veneers from 1.6 to 2.6. Premolars and first molars were included because its dark color intensifies the width buccal corridors. Also, the restoration with veneers from 3.3 to 4.3 was considered. Firstly, the veneers were removed and the color was selected by the Vitapan 3D Master guide (Vita Zahnfabrick, Bad Säckingen, Germany). Mock-up was made to evaluate aesthetic, phonetic and functional parameters. Then, teeth were prepared through the mock-up in order to reduce the minimal amount of dental tissue possible. Opaque dentine mass of microhybrid composite (Esthet-X A2O, Dentsply Sirona, Konstanz, Germany) was placed to mask the most intense stains. The definitive impressions were taken with silicone (Aquasil Ultra XLV, Dentsply Sirona, Konstanz, Germany) were taken to fabricate conventional feldsphatic ceramic veneers (Noritake kisai Co, Ltd. Japan) by the parallel stratification masking technique. For cementing, an opaque cement was selected from the try-in tests (Calibra, Dentsply Sirona, Konstanz, Germany) and the composite was silicatized with an air-abrasion device. A favorable and minimally invasive result was achieved to treat grade IV tetracycline stains, surpassing the patient's aesthetic expectations and functional needs. Key words: Porcelain veneer, tetracycline teeth, minimally invasive, masking, opaque composite.

  19. An overview of the main foodstuff sample preparation technologies for tetracycline residue determination.

    PubMed

    Pérez-Rodríguez, Michael; Pellerano, Roberto Gerardo; Pezza, Leonardo; Pezza, Helena Redigolo

    2018-05-15

    Tetracyclines are widely used for both the treatment and prevention of diseases in animals as well as for the promotion of rapid animal growth and weight gain. This practice may result in trace amounts of these drugs in products of animal origin, such as milk and eggs, posing serious risks to human health. The presence of tetracycline residues in foods can lead to the transmission of antibiotic-resistant pathogenic bacteria through the food chain. In order to ensure food safety and avoid exposure to these substances, national and international regulatory agencies have established tolerance levels for authorized veterinary drugs, including tetracycline antimicrobials. In view of that, numerous sensitive and specific methods have been developed for the quantification of these compounds in different food matrices. One will note, however, that the determination of trace residues in foods such as milk and eggs often requires extensive sample extraction and preparation prior to conducting instrumental analysis. Sample pretreatment is usually the most complicated step in the analytical process and covers both cleaning and pre-concentration. Optimal sample preparation can reduce analysis time and sources of error, enhance sensitivity, apart from enabling unequivocal identification, confirmation and quantification of target analytes. The development and implementation of more environmentally friendly analytical procedures, which involve the use of less hazardous solvents and smaller sample sizes compared to traditional methods, is a rapidly increasing trend in analytical chemistry. This review seeks to provide an updated overview of the main trends in sample preparation for the determination of tetracycline residues in foodstuffs. The applicability of several extraction and clean-up techniques employed in the analysis of foodstuffs, especially milk and egg samples, is also thoroughly discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Biodegradable Polymer Releasing Antibiotic Developed for Drainage Catheter of Cerebrospinal Fluid: In Vitro Results

    PubMed Central

    Han, Song Yup; Cho, Ki Hong; Cho, Han Jin; An, Jeong Ho; Ra, Young Sin

    2005-01-01

    The authors developed a biodegradable polymer that releases an antibiotic (nalidixic acid) slowly and continuously, for prevention of catheter-induced infection during drainage of cerebrospinal fluid. We investigated the in vitro antibiotic releasing characteristics and bacterial killing effects of the new polymer against E. coli. The novel fluoroquinolone polymer was prepared using diisopropylcarbodiimide, poly (e-caprolactone) diol, and nalidixic acid. FT-IR, mass spectrometry, and elemental analysis proved that the novel antibacterial polymer was prepared successfully without any side products. Negative MS showed that the released drug has a similar molecular weight (M.W.=232, 350) to pure drug (M.W.=232). In high pressure liquid chromatography, the released drug and drug-oligomer showed similar retention times (about 4.5-5 min) in comparison to pure drug (4.5 min). The released nalidixic acid and nalidixic acid derivatives have antibacterial characteristics against E. coli, Staphylococcus aureus, and Salmonella typhi, of more than 3 months duration. This study suggests the possibility of applying this new polymer to manufacture drainage catheters that resist catheter-induced infection, by delivering antibiotics for a longer period of more than 1 month. PMID:15832004

  1. Occurrence of tetracycline-resistant fecal coliforms and their resistance genes in an urban river impacted by municipal wastewater treatment plant discharges.

    PubMed

    Zhang, Chong-Miao; Du, Cong; Xu, Huan; Miao, Yan-Hui; Cheng, Yan-Yan; Tang, Hao; Zhou, Jin-Hong; Wang, Xiao-Chang

    2015-01-01

    Antibiotic resistance of fecal coliforms in an urban river poses great threats to both human health and the environment. To investigate the occurrence and distribution of antibiotic resistant bacteria in an urban river, water samples were collected from the Chanhe River in Xi'an, China. After membrane filtration of water samples, the tetracycline resistance rate of fecal coliforms and their resistance genes were detected by plating and polymerase chain reaction (PCR), respectively. We found that fecal coliforms were generally resistant to tetracycline and saw average resistance rates of 44.7%. The genes tetA and tetB were widely detected, and their positive rate was 60%-100% and 40%-90%, respectively. We found few strains containing tetC, tetK, tetQ and tetX, and we did not identify any strains containing tetG, tetM or tetO. The prevalence of tetA and tetB over other genes indicated that the main mechanism for resistance to tetracycline is by changes to the efflux pump. Our analysis of the types and proportion of tetracycline resistance genes in the Chanhe River at locations upstream and downstream of the urban center suggests that the increased number of tetracycline-resistant fecal coliforms and spatial variation of tetracycline resistance genes diversity were related to municipal wastewater treatment plant discharge.

  2. Protective Effect of Tetracycline against Dermal Toxicity Induced by Jellyfish Venom

    PubMed Central

    Kang, Changkeun; Jin, Yeung Bae; Kwak, Jeongsoo; Jung, Hongseok; Yoon, Won Duk; Yoon, Tae-Jin; Kim, Jong-Shu; Kim, Euikyung

    2013-01-01

    Background Previously, we have reported that most, if not all, of the Scyphozoan jellyfish venoms contain multiple components of metalloproteinases, which apparently linked to the venom toxicity. Further, it is also well known that there is a positive correlation between the inflammatory reaction of dermal tissues and their tissue metalloproteinase activity. Based on these, the use of metalloproteinase inhibitors appears to be a promising therapeutic alternative for the treatment of jellyfish envenomation. Methodology and Principal Findings Tetracycline (a metalloproteinase inhibitor) has been examined for its activity to reduce or prevent the dermal toxicity induced by Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom (NnV) using in vitro and in vivo models. HaCaT (human keratinocyte) and NIH3T3 (mouse fibroblast) incubated with NnV showed decreases in cell viability, which is associated with the inductions of metalloproteinase-2 and -9. This result suggests that the use of metalloproteinase inhibitors, such as tetracycline, may prevent the jellyfish venom-mediated local tissue damage. In vivo experiments showed that comparing with NnV-alone treatment, tetracycline pre-mixed NnV demonstrated a significantly reduced progression of dermal toxicity upon the inoculation onto rabbit skin. Conclusions/Significance It is believed that there has been no previous report on the therapeutic agent of synthetic chemical origin for the treatment of jellyfish venom-induced dermonecrosis based on understanding its mechanism of action except the use of antivenom treatment. Furthermore, the current study, for the first time, has proposed a novel mechanism-based therapeutic intervention for skin damages caused by jellyfish stings. PMID:23536767

  3. Efficient tetracycline adsorption and photocatalytic degradation of rhodamine B by uranyl coordination polymer

    NASA Astrophysics Data System (ADS)

    Ren, Ya-Nan; Xu, Wei; Zhou, Lin-Xia; Zheng, Yue-Qing

    2017-07-01

    Two mixed uranyl-cadmium malonate coordination polymers [(UO2)2Cd(H-bipy)2(mal)4(H2O)2]·4H2O 1 and [(UO2)Cd(bipy)(mal)2]·H2O 2 (H2mal = malonic acid, bipy =4,4‧-bipyridine) have been synthesized in room temperature. Compound 1 represents a one-dimensional (1D) chain assembly of Cd(II) ions, uranyl centers and malonate ligands. Compound 2 exhibits a two-dimensional (2D) 2D +2D → 3D polycatenated framework based on inclined interlocked 2D 44 sql grids. The two compounds have been characterized by elemental analysis, IR and UV-vis spectroscopy, thermal analysis, powder X-ray diffraction and photoluminescence spectroscopy. And the ferroelectric property of 2 also has been studied. Moreover, compound 2 exhibits good photocatalytic activity for dye degradation under UV light and is excellent adsorbent for removing tetracycline antibiotics in the aqueous solution.

  4. In vitro activity of five tetracyclines and some other antimicrobial agents against four porcine respiratory tract pathogens.

    PubMed

    Pijpers, A; Van Klingeren, B; Schoevers, E J; Verheijden, J H; Van Miert, A S

    1989-09-01

    The minimal inhibitory concentrations (MIC) of five tetracyclines and ten other antimicrobial agents were determined for four porcine bacterial respiratory tract pathogens by the agar dilution method. For the following oxytetracycline-susceptible strains, the MIC50 ranges of the tetracyclines were: P. multocida (n = 17) 0.25-0.5 micrograms/ml; B. bronchiseptica (n = 20) 0.25-1.0 micrograms/ml; H. pleuropneumoniae (n = 20) 0.25-0.5 micrograms/ml; S. suis Type 2 (n = 20) 0.06-0.25 micrograms/ml. For 19 oxytetracycline-resistant P. multocida strains the MIC50 of the tetracyclines varied from 64 micrograms/ml for oxytetracycline to 0.5 micrograms/ml for minocycline. Strikingly, minocycline showed no cross-resistance with oxytetracycline, tetracycline, chlortetracycline and doxycycline in P. multocida and in H. pleuropneumoniae. Moreover, in susceptible strains minocycline showed the highest in vitro activity followed by doxycycline. Low MIC50 values were observed for chloramphenicol, ampicillin, flumequine, ofloxacin and ciprofloxacin against P. multocida and H. pleuropneumoniae. B. bronchiseptica was moderately susceptible or resistant to these compounds. As expected tiamulin, lincomycin, tylosin and spiramycin were not active against H. pleuropneumoniae. Except for flumequine, the MIC50 values of nine antimicrobial agents were low for S. suis Type 2. Six strains of this species showed resistance to the macrolides and lincomycin.

  5. Physician Behavior Modification Using Claims Data: Tetracycline for Upper Respiratory Infection

    PubMed Central

    McConnell, Thomas S.; Cushing, Alice H.; Bankhurst, Arthur D.; Healy, James L.; McIlvenna, Patricia A.; Skipper, Betty J.

    1982-01-01

    Professional Standards Review Organization claims data were used in defining, planning, implementing and evaluating an approach to an ambulatory medical care problem utilizing educational intervention. Modification of physicians' tetracycline prescribing behavior was achieved in an actual practice setting by personal visits from peer physicians. PMID:6891147

  6. Antibiotic resistance phenotypes and virulence-associated genes in Escherichia coli isolated from animals and animal food products in Tunisia.

    PubMed

    Badi, Souhir; Cremonesi, Paola; Abbassi, Mohamed Salah; Ibrahim, Chourouk; Snoussi, Majdi; Bignoli, Giulia; Luini, Mario; Castiglioni, Bianca; Hassen, Abdennaceur

    2018-05-01

    Livestock and food products of animal origin constitute important reservoirs of intestinal and extraintestinal pathogenic Escherichia coli including antibiotic-resistant E. coli isolates. To assess potential risks to public health related to E. coli strains of animal origin in Tunisia, 65 E. coli isolates recovered from healthy animals and food products of animal origin were studied. Antimicrobial susceptibility was determined according to CLSI guidelines and genes encoding antibiotic resistance as well as virulence factors were investigated by PCR. High rates of antibiotic resistance were observed to kanamycin (78.4%), gentamicin (75.3%) and streptomycin (75.3%, encoded by strA-strB (7 isolates)), amoxicillin (64.6%), amoxicillin/clavulanic acid (60%), tetracycline (44.6%; tetA (8 isolates) and tetB (7 isolates)), nalidixic acid (27.6%, qnrS (3 isolates), qnrB (2 isolates) and qnrA (one isolate)) and sulfonamides (36.9%; sul1 (1 isolate), sul2 (4 isolates), and sul3 (1 isolate)). Virulotypes classified some isolates as STEC (3%), MNEC (1.5%) and atypical EPEC (1.5%). This study demonstrated high rates of antimicrobial resistance and the presence of some pathogenic pathovars from animal origins that are a cause of concern for public health.

  7. Effective Removal of Tetracycline Antibiotics from Water using Hybrid Carbon Membranes

    NASA Astrophysics Data System (ADS)

    Liu, Ming-Kai; Liu, Ying-Ya; Bao, Dan-Dan; Zhu, Gen; Yang, Guo-Hai; Geng, Jun-Feng; Li, Hai-Tao

    2017-03-01

    Antibiotic residues in drinking water have become a global problem, especially in developing countries. However, effective purification of water contaminated by antibiotics remains a great challenge. Here, we investigated the removing of tetracycline by carbon nanomaterials with different structures and surface functionalities. The result shows that a membrane of thick graphene oxide (GO) and activated carbon (AC) with a thickness of 15 μm can effectively remove 98.9% of tetracycline hydrochloride (TCH) from water by vacuum filtration. Structural analysis indicated that the AC nanoparticles were uniformly inserted into the GO interstitial sites without any aggregations. Also, GO sheets were loosened by the encapsulated AC nanoparticles, leading to the formation of numerous tiny pores (3-10 nm) that acted as channels for fluid passage, whereas the carbons and chemical groups on the GO surface adsorbed TCH. GO/AC membrane exhibits the best adsorption efficiency among the investigated materials, including pure GO, AC, carbon nanotube (CNT), and CNT/AC and GO/CNT hybrids.

  8. Isolation and molecular characterization of Salmonella enterica serovar Enteritidis from poultry house and clinical samples during 2010.

    PubMed

    Mezal, Ezat H; Sabol, Ashley; Khan, Mariam A; Ali, Nawab; Stefanova, Rossina; Khan, Ashraf A

    2014-04-01

    A total of 60 Salmonella enterica serovar (ser.) Enteritidis isolates, 28 from poultry houses and 32 from clinical samples, were isolated during 2010. These isolates were subjected to testing and analyzed for antibiotic resistance, virulence genes, plasmids and plasmid replicon types. To assess genetic diversity, pulsed-field gel electrophoresis (PFGE) fingerprinting, using the XbaI restriction enzyme, Multiple-Locus Variable-Number Tandem Repeat Analysis (MLVA) and plasmid profiles were performed. All isolates from poultry, and 10 out of 32 clinical isolates were sensitive to ampicillin, chloramphenicol, gentamicin, kanamycin, nalidixic acid, sulfisoxazole, streptomycin, and tetracycline. Twenty-one of thirty-two clinical isolates were resistant to ampicillin and tetracycline, and one isolate was resistant to nalidixic acid. PFGE typing of sixty ser. Enteritidis isolates by XbaI resulted in 10-12 bands and grouped into six clusters each with similarity from 95% to 81%. The MLVA analysis of sixty isolates gave 18 allele profiles with the majority of isolates displayed in three groups, and two clinical isolates found to be new in the PulseNet national MLVA database. All isolates were positive for 12 or more of the 17 virulence genes mostly found in S. enterica (spvB, spiA, pagC, msgA, invA, sipB, prgH, spaN, orgA, tolC, iroN, sitC, IpfC, sifA, sopB, and pefA) and negative for one gene (cdtB). All isolates carried a typical 58 kb plasmid, type Inc/FIIA. Three poultry isolates and one clinical isolate carried small plasmids with 3.8, 6, 7.6 and 11.5 kb. Ten of the clinical isolates carried plasmids, with sizes 36 and 38 kb, types IncL/M and IncN, and one isolate carried an 81 kb plasmid, type IncI. Southern hybridization of a plasmid with an Inc/FIIA gene probe hybridized one large 58 kb plasmid in all isolates. Several large and small plasmids from poultry isolates were not typed by our PCR-based method. These results confirmed that PFGE fingerprinting has

  9. A novel solid digestate-derived biochar-Cu NP composite activating H2O2 system for simultaneous adsorption and degradation of tetracycline.

    PubMed

    Fu, Dun; Chen, Zheng; Xia, Dong; Shen, Liang; Wang, Yuanpeng; Li, Qingbiao

    2017-02-01

    Solid digestate, a by-product of anaerobic digestion systems, has led to a range of environmental issues. In the present study, a novel composite based on a solid digestate-biochar-Cu NP composite was synthesized for tetracycline removal from an aqueous medium. The removal efficiency values for tetracycline (200 mg L -1 ) were 31.5% and 97.8%, respectively, by the biochar-Cu NP composite (0.5 g L -1 ) in the absence and presence of hydrogen peroxide (H 2 O 2 , 20 mM) within 6 h of reaction time. The possible degradation pathway of tetracycline was investigated using liquid chromatography-mass spectrometry. The desorption experiment results suggested that no significant concentration of tetracycline was detected on the composite after the reaction, but a small amount of intermediates in terms of total organic carbon (TOC) accounting for 3.1%, and 23.3% of the end-product NH 4 + was adsorbed onto the biochar sheets. The dispersive Cu NPs on the biochar resulted in an increase in the surface area and pore volume of the biochar-Cu NP composite, which enhanced tetracycline adsorption as well as the degradation efficiency. Relative tetracycline removal mechanisms were dominantly ascribed to ·OH generation from the Cu(II)/Cu(I) redox reaction with H 2 O 2 and the electron-transfer process of free radicals (FRs) in biochar. The proposed approach serves dual purposes of waste digestate reuse and treatment of antibiotic pollutants. This study highlights the activation of H 2 O 2 by the dispersive Cu NPs coupling with biochar derived from a waste solid digestate for tetracycline treatment. Copyright © 2016. Published by Elsevier Ltd.

  10. 75 FR 12981 - Oral Dosage Form New Animal Drugs; Tetracycline Powder

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-18

    .... FDA-2010-N-0002] Oral Dosage Form New Animal Drugs; Tetracycline Powder AGENCY: Food and Drug... amending the animal drug regulations to reflect approval of a supplemental new animal drug application... approval of this product. This change is being made to improve the accuracy of the animal drug regulations...

  11. Consequences of tetracycline exposure to stream periphyton in an experimental mesocosm study

    EPA Science Inventory

    A significant amount of ingested, injected, and applied antibiotics are not metabolized but are excreted; entering the environment via point and non-point sources. Tetracycline and its derivatives are among the most extensively used human and animal antibiotics. We examined the ...

  12. The use of dissolvable layered double hydroxide components in an in situ solid-phase extraction for chromatographic determination of tetracyclines in water and milk samples.

    PubMed

    Phiroonsoontorn, Nattaphorn; Sansuk, Sira; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

    2017-10-13

    This research presents a simple and green in situ solid phase extraction (is-SPE) combined with high-performance liquid chromatography (HPLC) for the simultaneous analysis of tetracyclines (TCs) including tetracycline, oxytetracycline, and chlortetracycline. In is-SPE, TCs were efficiently extracted through the precipitation formation of dissolvable layered double hydroxides (LDHs) by mixing the LDH components such as magnesium and aluminum ions (both in metal chloride salts) thoroughly in an alkaline sample solution. After the centrifugation, the precipitate was completely dissolved with trifluoroacetic acid to release the enriched TCs, and then analyzed by HPLC. Under optimized conditions, this method gave good enrichment factors (EFs) of 41-93 with low limits of detection (LODs) of 0.7-6μg/L and limits of quantitation (LOQs) of 3-15μg/L. Also, the proposed method was successfully applied for the determination of TCs in water and milk samples with the recoveries ranging from 81.7-108.1% for water and 55.7-88.7% for milk. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Comparative trial of rifampin-doxycycline versus tetracycline-streptomycin in the therapy of human brucellosis.

    PubMed Central

    Ariza, J; Gudiol, F; Pallarés, R; Rufí, G; Fernández-Viladrich, P

    1985-01-01

    In an attempt to compare the efficacy of rifampin-doxycycline with tetracycline-streptomycin for the treatment of human brucellosis, we administered both combinations for a 30-day period, similar to the period recommended by the World Health Organization in a prospective, randomized trial. Forty-six patients were included in the final study (36 men and 10 women); 41 had blood cultures positive for Brucella melitensis. The 28 patients in group A received tetracycline hydrochloride at doses of 0.5 g every 6 h or doxycycline at 100 mg every 12 h for 30 days plus 1 g of streptomycin a day for 21 days. The 18 patients in group B received rifampin at 15 mg/kg per day in a single morning dose plus 100 mg of doxycycline every 12 h for 30 days. For patients with focal disease from both groups, therapy was prolonged to 45 days. All patients underwent rigorous clinical and bacteriological long-term follow-up. There were no therapeutic failures in either group, and the defervescence period was similar for both groups (3.1 days for group A, 2.6 days for group B). Two patients (7.1%) from group A had relapses, as did seven (38.8%) from group B (P = 0.024), and blood cultures again became positive for B. melitensis in all of them. In both groups treatment was generally well tolerated. The results strongly suggest that the rifampin-doxycycline combination is a less efficacious mode of therapy for brucellosis to prevent relapses than is the classical tetracycline-streptomycin combination when both are administered for 30 days. A more prolonged period of administration of the rifampin-doxycycline combination may be required to obtain the same low relapse rate as that achieved with the classical tetracycline-streptomycin treatment. PMID:4073878

  14. Safety mechanism assisted by the repressor of tetracycline (SMART) vaccinia virus vectors for vaccines and therapeutics.

    PubMed

    Grigg, Patricia; Titong, Allison; Jones, Leslie A; Yilma, Tilahun D; Verardi, Paulo H

    2013-09-17

    Replication-competent viruses, such as Vaccinia virus (VACV), are powerful tools for the development of oncolytic viral therapies and elicit superior immune responses when used as vaccine and immunotherapeutic vectors. However, severe complications from uncontrolled viral replication can occur, particularly in immunocompromised individuals or in those with other predisposing conditions. VACVs constitutively expressing interferon-γ (IFN-γ) replicate in cell culture indistinguishably from control viruses; however, they replicate in vivo to low or undetectable levels, and are rapidly cleared even in immunodeficient animals. In an effort to develop safe and highly effective replication-competent VACV vectors, we established a system to inducibly express IFN-γ. Our SMART (safety mechanism assisted by the repressor of tetracycline) vectors are designed to express the tetracycline repressor under a constitutive VACV promoter and IFN-γ under engineered tetracycline-inducible promoters. Immunodeficient SCID mice inoculated with VACVs not expressing IFN-γ demonstrated severe weight loss, whereas those given VACVs expressing IFN-γ under constitutive VACV promoters showed no signs of infection. Most importantly, mice inoculated with a VACV expressing the IFN-γ gene under an inducible promoter remained healthy in the presence of doxycycline, but exhibited severe weight loss in the absence of doxycycline. In this study, we developed a safety mechanism for VACV based on the conditional expression of IFN-γ under a tightly controlled tetracycline-inducible VACV promoter for use in vaccines and oncolytic cancer therapies.

  15. 21 CFR 520.2345g - Tetracycline hydrochloride and sodium novobiocin tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... tablets. 520.2345g Section 520.2345g Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2345g Tetracycline hydrochloride and sodium novobiocin tablets. (a) Specifications. Each tablet... antibiotic per pound of body weight (one single-strength tablet for each 6 pounds or one triple-strength...

  16. [Hygienic substantiation of the permissible levels for tetracycline-group antibiotics in food].

    PubMed

    Onishchenko, G G; Sheveleva, S A; Khotimchenko, S A

    2012-01-01

    For the purpose of justification of the hygienic standard for tetracycline-group antibiotics in the food production established in the Russian Federation at more rigid level, than maximum and admissible levels (MAL) of the Codex Alimentarius Commission, the analysis of data of literature on negative nature of impact of low concentration of these antibiotics on an organism and the environmental conditions and risk for health has been performed. Inadequacy of the accepted admissible daily dose (ADD) accepted by The Joint FAO/WHO Expert Committee on Food Additives (JECFA) on action on selection of resistant E. coli in intestines, for the wide contingent of consumers in connection with ignoring of obvious factors of uncertainty (gastrointestinal dysbiosis, age and individual variations in the microbiota of people synergy with other antibiotics residues in food and indirect impact on an organism through microflora from the natural habitat (resistance genes, modified causative organisms with altered properties).. By the analysis of information received with the use of modern molecular and genetic methods, the role of Subinhibitory concentrations (sub-MICs) of tetracyclines as biologically active substances, signaling molecules which, without causing obvious negative consequences in a macroorganism, serve as a major factor of regulation of a transcription in microorganisms and activation of a horizontal gene transfer coding resistance, transferred on conjugative transposons of Tn916-Tn1545 family. Reasonable scientific data on a dominating contribution of minor levels of tetracyclines in globalization in the nature of the most adverse transmissive type of the antibiotic resistance interfaced to formation new bacterial pathotypes, as consequences of irrationally high scales of application in agriculture and strengthened impact on microbic ecosystems of live organisms and objects of habitat are presented. For minimization of this mediated risk for health the need of

  17. Biogas generation in anaerobic wastewater treatment under tetracycline antibiotic pressure

    NASA Astrophysics Data System (ADS)

    Lu, Meiqing; Niu, Xiaojun; Liu, Wei; Zhang, Jun; Wang, Jie; Yang, Jia; Wang, Wenqi; Yang, Zhiquan

    2016-06-01

    The effect of tetracycline (TC) antibiotic on biogas generation in anaerobic wastewater treatment was studied. A lab-scale Anaerobic Baffled Reactor (ABR) with three compartments was used. The reactor was operated with synthetic wastewater in the absence of TC and in the presence of 250 μg/L TC for 90 days, respectively. The removal rate of TC, volatile fatty acids (VFAs), biogas compositions (hydrogen (H2), methane (CH4), carbon dioxide (CO2)), and total biogas production in each compartment were monitored in the two operational conditions. Results showed that the removal rate of TC was 14.97-67.97% in the reactor. The presence of TC had a large negative effect on CH4 and CO2 generation, but appeared to have a positive effect on H2 production and VFAs accumulation. This response indicated that the methanogenesis process was sensitive to TC presence, but the acidogenesis process was insensitive. This suggested that the presence of TC had less influence on the degradation of organic matter but had a strong influence on biogas generation. Additionally, the decrease of CH4 and CO2 generation and the increase of H2 and VFAs accumulation suggest a promising strategy to help alleviate global warming and improve resource recovery in an environmentally friendly approach.

  18. Tetracycline Selective Pressure and Homologous Recombination Shape the Evolution of Chlamydia suis: A Recently Identified Zoonotic Pathogen.

    PubMed

    Joseph, Sandeep J; Marti, Hanna; Didelot, Xavier; Read, Timothy D; Dean, Deborah

    2016-09-02

    Species closely related to the human pathogen Chlamydia trachomatis (Ct) have recently been found to cause zoonotic infections, posing a public health threat especially in the case of tetracycline resistant Chlamydia suis (Cs) strains. These strains acquired a tet(C)-containing cassette via horizontal gene transfer (HGT). Genomes of 11 Cs strains from various tissues were sequenced to reconstruct evolutionary pathway(s) for tet(C) HGT. Cs had the highest recombination rate of Chlamydia species studied to date. Admixture occurred among Cs strains and with Chlamydia muridarum but not with Ct Although in vitro tet(C) cassette exchange with Ct has been documented, in vivo evidence may require examining human samples from Ct and Cs co-infected sites. Molecular-clock dating indicated that ancestral clades of resistant Cs strains predated the 1947 discovery of tetracycline, which was subsequently used in animal feed. The cassette likely spread throughout Cs strains by homologous recombination after acquisition from an external source, and our analysis suggests Betaproteobacteria as the origin. Selective pressure from tetracycline may be responsible for recent bottlenecks in Cs populations. Since tetracycline is an important antibiotic for treating Ct, zoonotic infections at mutual sites of infection indicate the possibility for cassette transfer and major public health repercussions. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  19. Novel and remarkable enhanced-fluorescence system based on gold nanoclusters for detection of tetracycline.

    PubMed

    Yang, Xiaoming; Zhu, Shanshan; Dou, Yao; Zhuo, Yan; Luo, Yawen; Feng, Yuanjiao

    2014-05-01

    Tetracycline and Eu(3+), while coexisting, usually appear as a complex by chelating. This complex shows low fluorescence intensity, leading to its limitation of analytical goals. Gold nanoclusters (AuNCs), emerging as novel nano-material, are attracting increasing attentions in multiple fields. Herein, gold nanoclusters first function as a fluorescence-enhanced reagent rather than a conventional fluorescent-probe, and a dramatic enhanced-fluorescence system was built based on Eu(3+)-Tetracycline complex (EuTC) by introducing gold nanoclusters. Simultaneously, three types of gold nanoclusters were employed for exploring various conditions likely affecting the system, which demonstrate that no other gold nanoclusters than DNA-templated gold nanoclusters enormously caused fluorescence-enhancement of EuTC. Moreover, this enhanced-fluorescence system permitted available detection of tetracycline (TC) in a linear range of 0.01-5 μM, with a detection limit of 4 nM at a signal-to-noise ratio of 3. Significantly, the practicality of this method for detection of TC in human urine and milk samples was validated, demonstrating its advantages of simplicity, sensitivity and low cost. Interestingly, this system described here is probably promising for kinds of applications based on its dramatically enhanced-fluorescence. © 2013 Published by Elsevier B.V.

  20. Preparation and evaluation of an adsorbent based on poly (muconic acid-co-divinylbenzene/ethylenedimethacrylate) for multiple monolithic fiber solid-phase microextraction of tetracycline antibiotics.

    PubMed

    Pei, Miao; Huang, Xiaojia

    2017-09-29

    To extract tetracycline antibiotics (TAs) effectively, a new adsorbent based on poly (muconic acid-co-divinylbenzene/ethylenedimethacrylate) monolith was fabricated and used as the extraction medium of multiple monolithic fiber solid-phase microextraction (MD/MF-SPME). The effect of the fabrication parameters on extraction efficiency was studied thoroughly. Elemental analysis, infrared spectroscopy, scanning electron microscopy and mercury intrusion porosimetry were used to check the physicochemical properties of the adsorbent. Some key parameters that affect the extraction performance of MD/MF-SPME for TAs were investigated systematically. Under the optimized experimental conditions, the prepared adsorbent could effectively extract the TAs through multiple interactions. At the same time, a simple and sensitive method for monitoring trace TAs in honey samples was developed by coupling MD/MF-SPME with high-performance liquid chromatography tandem mass spectrometry detection (MD/MF-SPME-HPLC-MS/MS). The limits of detection (S/N=3) for target compounds were in the range of 7.3-17.1ng/kg. The intra-day and inter-day precision (relative standard deviations, n=4, %) at 0.5μg/kg and 20.0μg/kg spiking concentrations were 5.0-9.5% and 3.6-10.0%, respectively. The mean recoveries of the target TAs in the real honey samples were between 70.5-111.0%. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Influence of long-term treatment with tetracycline and niacinamide on antibody production in dogs with discoid lupus erythematosus.

    PubMed

    Mueller, Ralf S; Fieseler, Kathryn V; Bettenay, Sonya V; Rosychuk, Rodney A W

    2002-04-01

    To evaluate the effect of long-term treatment with tetracycline and niacinamide on antibody production in dogs by measuring postvaccinal serum concentrations of antibodies against canine parvovirus and canine distemper virus. 10 dogs receiving long-term treatment with tetracycline and niacinamide (treatment group) and 10 healthy dogs (control group). The treatment group included 9 dogs with discoid lupus erythematosus and 1 dog with pemphigus foliaceus on long-term treatment (> 12 months) with tetracycline and niacinamide. The control group included 10 healthy dogs with no clinical signs of disease and no administered medications for the past 3 months. Blood samples were obtained from all dogs by jugular venipuncture. Serum antibody titers against canine parvovirus and canine distemper virus antigens were measured, using hemaglutination inhibition and serum neutralization, respectively, and compared between groups. A significant difference in antibody titers between treatment- and control-group dogs was not found. All dogs had protective antibody titers against canine distemper virus, and 8 of 10 dogs from each group had protective titers against canine parvovirus infection. These results provide evidence that long-term treatment with tetracycline and niacinamide does not interfere with routine vaccinations and thus does not seem to influence antibody production in dogs.

  2. Influence of montmorillonite on antimicrobial activity of tetracycline and ciprofloxacin

    NASA Astrophysics Data System (ADS)

    Lv, Guocheng; Pearce, Cody W.; Gleason, Andrea; Liao, Libing; MacWilliams, Maria P.; Li, Zhaohui

    2013-11-01

    Antibiotics are used not only to fight infections and inhibit bacterial growth, but also as growth promotants in farm livestock. Farm runoff and other farm-linked waste have led to increased antibiotic levels present in the environment, the impact of which is not completely understood. Soil, more specifically clays, that the antibiotic contacts may alter its effectiveness against bacteria. In this study a swelling clay mineral montmorillonite was preloaded with antibiotics tetracycline and ciprofloxacin at varying concentrations and bioassays were conducted to examine whether the antibiotics still inhibited bacterial growth in the presence of montmorillonite. Escherichia coli was incubated with montmorillonite or antibiotic-adsorbed montmorillonite, and then the number of viable bacteria per mL was determined. The antimicrobial activity of tetracycline was affected in the presence of montmorillonite, as the growth of non-resistant bacteria was still found even when extremely high TC doses were used. Conversely, in the presence of montmorillonite, ciprofloxacin did inhibit E. coli bacterial growth at high concentrations. These results suggest that the effectiveness of antimicrobial agents in clayey soils depends on the amount of antibiotic substance present, and on the interactions between the antibiotic and the clays in the soil, as well.

  3. Controlled release of tetracycline-HCl from halloysite-polymer composite films.

    PubMed

    Ward, Christopher J; Song, Shang; Davis, Edward W

    2010-10-01

    The first direct comparison between two common methods for loading halloysite with a small molecule for controlled release is presented. While the methods differ in the degree of simplicity, they provide essentially the same level of loading and release kinetics. A tentative explanation of the "burst" effect often seen in the release of low molecular weight molecules from halloysite is provided. The ability of halloysite to mediate the release rate of a water soluble drug, tetracycline, from solution cast polyvinyl alcohol and polymethyl methacrylate films was evaluated. In some films, montmorillonite was also incorporated. The addition of montmorillonite to solutions used to cast tetracycline containing films significantly reduced the release rate from the dried films. The same overall effect was seen when the drug was loaded into halloysite prior to preparation of the films. In both cases, the release was best fit with the simple Higuchi model. However, when montmorillonite was added to solutions of polyvinyl alcohol and drug loaded halloysite the release profiles were better fit by the Ritgar-Peppas model for anomalous transport. Release from polymethyl methacrylate was reduced by a factor of three by incorporating the drug in halloysite prior to producing the films.

  4. A PhoPQ-Regulated ABC Transporter System Exports Tetracycline in Pseudomonas aeruginosa.

    PubMed

    Chen, Lin; Duan, Kangmin

    2016-05-01

    Pseudomonas aeruginosa is an important human pathogen whose infections are difficult to treat due to its high intrinsic resistance to many antibiotics. Here, we show that the disruption of PA4456, encoding the ATP binding component of a putative ATP-binding cassette (ABC) transporter, increased the bacterium's susceptible to tetracycline and other antibiotics or toxic chemicals. Fluorescence spectroscopy and antibiotic accumulation tests showed that the interruption of the ABC transporter caused increased intracellular accumulation of tetracycline, demonstrating a role of the ABC transporter in tetracycline expulsion. Site-directed mutagenesis proved that the conserved residues of E170 in the Walker B motif and H203 in the H-loop, which are important for ATP hydrolysis, were essential for the function of PA4456. Through a genome-wide search, the PhoPQ two-component system was identified as a regulator of the computationally predicted PA4456-4452 operon that encodes the ABC transporter system. A >5-fold increase of the expression of this operon was observed in the phoQ mutant. The results obtained also show that the expression of the phzA1B1C1D1E1 operon and the production of pyocyanin were significantly higher in the ABC transporter mutant, signifying a connection between the ABC transporter and pyocyanin production. These results indicated that the PhoPQ-regulated ABC transporter is associated with intrinsic resistance to antibiotics and other adverse compounds in P. aeruginosa, probably by extruding them out of the cell. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  5. DNA gyrase inhibitors block development of Bacillus subtilis bacteriophage SP01.

    PubMed Central

    Alonso, J C; Sarachu, A N; Grau, O

    1981-01-01

    SP01 development was inhibited by nalidixic acid and novobiocin in the sensitive host Bacillus subtilis 168M. Inhibition by novobiocin was prevented by a Novr mutation in the cellular DNA gyrase gene. Nalidixic acid inhibition persisted in hosts carrying a Nalr gyrase, but could be overcome by phage mutation. We conclude that SP01 requires for its development subunit B of the host DNA gyrase, but replaces or modifies subunit A. PMID:6270354

  6. Solution blow spun Poly(lactic acid)/Hydroxypropyl methylcellulose nanofibers with antimicrobial properties

    USDA-ARS?s Scientific Manuscript database

    Poly(lactic acid) (PLA) nanofibers containing hydroxypropyl methylcellulose (HPMC) and tetracycline hydrochloride (THC) were solution blow spun from two different solvents, chloroform/acetone (CA, 80:20 v/v) and 2,2,2-triflouroethanol (TFE). The diameter distribution, chemical, thermal, thermal stab...

  7. Development of an automatic high-throughput assay for tetracycline determination by using Eu2O3 nanoparticles and dry-reagent technology.

    PubMed

    Aguilar-Vázquez, L; Aguilar-Caballos, M P; Gómez-Hens, A

    2014-02-01

    The usefulness of europium oxide nanoparticles (Eu2O3 NPs) as analytical reagent for the direct determination of organic compounds is described for the first time. Tetracycline, which forms a luminescent chelate with europium, has been chosen as a model analyte. Dry reagent chemistry is used in a 96-well format, which considerably speeds up the determination and contributes to its automation. The NPs are immobilized onto polystyrene wells by adding a volume of a Eu2O3 NP dispersion in 2-propanol to each well and drying in an oven until they dry completely. At the moment of analysis, a standard or sample volume (200 μL) in the appropriate medium is added, and the mixture shaken for 15 min at 37°C. The method allows the determination of tetracycline in the range 20-1000 ng mL(-1), with a detection limit of 8 ng mL(-1). The inter-assay and intra-assay precision, which were assayed at two different tetracycline concentrations and expressed as relative standard deviation, were in the ranges of 6.5-8.2% and 9.2-12.7%, respectively. The study of the selectivity of the system showed that the method is adequate for tetracycline determination in agri-food samples, since most of antibiotics assayed did not interfere the determination. Only other tetracycline antibiotics provided luminescent signal when reacting to Eu2O3 NPs. The method has been applied to the determination of tetracycline in calf urine and in honey samples obtaining recovery values in the ranges of 85.0-110.0% and 99.7-116.7%, respectively. © 2013 Published by Elsevier B.V.

  8. Mark-recapture using tetracycline and genetics reveal record-high bear density

    USGS Publications Warehouse

    Peacock, E.; Titus, K.; Garshelis, D.L.; Peacock, M.M.; Kuc, M.

    2011-01-01

    We used tetracycline biomarking, augmented with genetic methods to estimate the size of an American black bear (Ursus americanus) population on an island in Southeast Alaska. We marked 132 and 189 bears that consumed remote, tetracycline-laced baits in 2 different years, respectively, and observed 39 marks in 692 bone samples subsequently collected from hunters. We genetically analyzed hair samples from bait sites to determine the sex of marked bears, facilitating derivation of sex-specific population estimates. We obtained harvest samples from beyond the study area to correct for emigration. We estimated a density of 155 independent bears/100 km2, which is equivalent to the highest recorded for this species. This high density appears to be maintained by abundant, accessible natural food. Our population estimate (approx. 1,000 bears) could be used as a baseline and to set hunting quotas. The refined biomarking method for abundance estimation is a useful alternative where physical captures or DNA-based estimates are precluded by cost or logistics. Copyright ?? 2011 The Wildlife Society.

  9. Reversible cytotoxic oedema in the splenium of the corpus callosum related to tetracycline therapy.

    PubMed

    Grühbaum, Barbara; Salzer, Hans; Nasel, Christian; Lernbass, Isolde

    2010-10-01

    We report a symptomatic girl with reversible circumscribed cytotoxic oedema in the splenium of the corpus callosum (CC) that occurred, to our knowledge, for the first time in relation to tetracycline treatment. After stopping tetracycline therapy the girl recovered completely and the CC lesion, clearly visible on diffusion-weighted MR imaging (DWI), disappeared. Reversible circumscribed cytotoxic oedema (CCO) of the splenium of the CC is a well-defined entity that is found to be associated with administration of antiepileptic drugs, alterations in therapy using arginin-vasopressin and metronidazole or infections with influenza and rotavirus. CCO of splenium of the CC is clearly visible on DWI, shows no enhancement after administration of contrast medium and is completely reversible in most cases.

  10. Comparison of the Prevalences and Antimicrobial Resistances of Escherichia coli Isolates from Different Retail Meats in the United States, 2002 to 2008

    PubMed Central

    Blickenstaff, K.; Bodeis-Jones, S.; Gaines, S. A.; Tong, E.; McDermott, P. F.

    2012-01-01

    Escherichia coli isolates were recovered from the National Antimicrobial Resistance Monitoring System retail meat program and examined for antimicrobial susceptibility. Retail meat samples (n = 11,921) from four U.S. states collected during 2002 to 2008, consisting of 2,988 chicken breast, 2,942 ground turkey, 2,991 ground beef, and 3,000 pork chop samples, were analyzed. A total of 8,286 E. coli isolates were recovered. The greatest numbers of samples contaminated with the organism were chicken (83.5%) and turkey (82.0%), followed by beef (68.9%) and pork (44.0%). Resistance was most common to tetracycline (50.3%), followed by streptomycin (34.6%), sulfamethoxazole-sulfisoxazole (31.6%), ampicillin (22.5%), gentamicin (18.6%), kanamycin (8.4%), amoxicillin-clavulanic acid (6.4%), and cefoxitin (5.2%). Less than 5% of the isolates had resistance to trimethoprim, ceftriaxone, ceftiofur, nalidixic acid, chloramphenicol, and ciprofloxacin. All isolates were susceptible to amikacin. Compared to beef and pork isolates, the poultry meat isolates had a greater percentage of resistance to all tested drugs, with the exception of chloramphenicol, to which pork isolates had the most resistance. More than half of the turkey isolates (56%) were resistant to multidrugs (≥3 classes) compared to 38.9% of chicken, 17.3% of pork, and 9.3% of beef isolates. The blaCMY gene was present in all ceftriaxone- and ceftiofur-resistant isolates. The cmlA, flo, and catI genes were present in 45%, 43%, and 40% of chloramphenicol-resistant isolates, respectively. Most nalidixic acid-resistant isolates (98.5%) had a gyrA mutation in S83 or D87 or both, whereas only 6.7% had a parC mutation in either S80 or E84. The results showed that E. coli was commonly present in the retail meats, and antimicrobial resistance profiles differed according to the animal origin of the isolates. PMID:22247155

  11. Comparative analysis of antimicrobial resistance in enterotoxigenic Escherichia coli isolates from two paediatric cohort studies in Lima, Peru

    PubMed Central

    Medina, Anicia M.; Rivera, Fulton P.; Pons, Maria J.; Riveros, Maribel; Gomes, Cláudia; Bernal, María; Meza, Rina; Maves, Ryan C.; Huicho, Luis; Chea-Woo, Elsa; Lanata, Claudio F.; Gil, Ana I.; Ochoa, Theresa J.; Ruiz, Joaquim

    2015-01-01

    Background Antibiotic resistance is increasing worldwide, being of special concern in low- and middle-income countries. The aim of this study was to determine the antimicrobial susceptibility and mechanisms of resistance in 205 enterotoxigenic Escherichia coli (ETEC) isolates from two cohort studies in children <24 months in Lima, Peru. Methods ETEC were identified by an in-house multiplex real-time PCR. Susceptibility to 13 antimicrobial agents was tested by disk diffusion; mechanisms of resistance were evaluated by PCR. Results ETEC isolates were resistant to ampicillin (64%), cotrimoxazole (52%), tetracycline (37%); 39% of the isolates were multidrug-resistant. Heat-stable toxin producing (ETEC-st) (48%) and heat-labile toxin producing ETEC (ETEC-lt) (40%) had higher rates of multidrug resistance than isolates producing both toxins (ETEC-lt-st) (21%), p<0.05. Only 10% of isolates were resistant to nalidixic acid and none to ciprofloxacin or cefotaxime. Ampicillin and sulfamethoxazole resistance were most often associated with blaTEM (69%) and sul2 genes (68%), respectively. Tetracycline resistance was associated with tet(A) (49%) and tet(B) (39%) genes. Azithromycin inhibitory diameters were ≤15 mm in 36% of isolates, with 5% of those presenting the mph(A) gene. Conclusions ETEC from Peruvian children are often resistant to older, inexpensive antibiotics, while remaining susceptible to ciprofloxacin, cephalosporins and furazolidone. Fluoroquinolones and azithromycin remain the drugs of choice for ETEC infections in Peru. However, further development of resistance should be closely monitored. PMID:26175267

  12. Patterns of Antimicrobial Resistance Observed in Escherichia coli Isolates Obtained from Domestic- and Wild-Animal Fecal Samples, Human Septage, and Surface Water

    PubMed Central

    Sayah, Raida S.; Kaneene, John B.; Johnson, Yvette; Miller, RoseAnn

    2005-01-01

    A repeated cross-sectional study was conducted to determine the patterns of antimicrobial resistance in 1,286 Escherichia coli strains isolated from human septage, wildlife, domestic animals, farm environments, and surface water in the Red Cedar watershed in Michigan. Isolation and identification of E. coli were done by using enrichment media, selective media, and biochemical tests. Antimicrobial susceptibility testing by the disk diffusion method was conducted for neomycin, gentamicin, streptomycin, chloramphenicol, ofloxacin, trimethoprim-sulfamethoxazole, tetracycline, ampicillin, nalidixic acid, nitrofurantoin, cephalothin, and sulfisoxazole. Resistance to at least one antimicrobial agent was demonstrated in isolates from livestock, companion animals, human septage, wildlife, and surface water. In general, E. coli isolates from domestic species showed resistance to the largest number of antimicrobial agents compared to isolates from human septage, wildlife, and surface water. The agents to which resistance was demonstrated most frequently were tetracycline, cephalothin, sulfisoxazole, and streptomycin. There were similarities in the patterns of resistance in fecal samples and farm environment samples by animal, and the levels of cephalothin-resistant isolates were higher in farm environment samples than in fecal samples. Multidrug resistance was seen in a variety of sources, and the highest levels of multidrug-resistant E. coli were observed for swine fecal samples. The fact that water sample isolates were resistant only to cephalothin may suggest that the resistance patterns for farm environment samples may be more representative of the risk of contamination of surface waters with antimicrobial agent-resistant bacteria. PMID:15746342

  13. PFGE, Lior serotype, and antimicrobial resistance patterns among Campylobacter jejuni isolated from travelers and US military personnel with acute diarrhea in Thailand, 1998-2003

    PubMed Central

    2010-01-01

    Background Campylobacter jejuni is a major cause of gastroenteritis worldwide. In Thailand, several strains of C. jejuni have been isolated and identified as major diarrheal pathogens among adult travelers. To study the epidemiology of C. jejuni in adult travelers and U.S. military personnel with acute diarrhea in Thailand from 1998-2003, strains of C. jejuni were isolated and phenotypically identified, serotyped, tested for antimicrobial susceptibility, and characterized using pulsed-field gel electrophoresis (PFGE). Results A total of 312 C. jejuni isolates were obtained from travelers (n = 46) and U.S. military personnel (n = 266) in Thailand who were experiencing acute diarrhea. Nalidixic acid and ciprofloxacin resistance was observed in 94.9% and 93.0% of the isolates, respectively. From 2001-2003, resistance to tetracycline (81.9%), trimethoprim-sulfamethoxazole (57.9%), ampicillin (28.9%), kanamycin (5.9%), sulfisoxazole (3.9%), neomycin (2.0%), and streptomycin (0.7%) was observed. Combined PFGE analysis showed considerable genetic diversity among the C. jejuni isolates; however, four PFGE clusters included isolates from the major Lior serotypes (HL: 36, HL: 11, HL: 5, and HL: 28). The PFGE analysis linked individual C. jejuni clones that were obtained at U.S. military exercises with specific antimicrobial resistance patterns. Conclusions In summary, most human C. jejuni isolates from Thailand were multi-resistant to quinolones and tetracycline. PFGE detected spatial and temporal C. jejuni clonality responsible for the common sources of Campylobacter gastroenteritis. PMID:21062505

  14. Evaluation of the Charm maximum residue limit β-lactam and tetracycline test for the detection of antibiotics in ewe and goat milk.

    PubMed

    Beltrán, M C; Romero, T; Althaus, R L; Molina, M P

    2013-05-01

    The Charm maximum residue limit β-lactam and tetracycline test (Charm MRL BLTET; Charm Sciences Inc., Lawrence, MA) is an immunoreceptor assay utilizing Rapid One-Step Assay lateral flow technology that detects β-lactam or tetracycline drugs in raw commingled cow milk at or below European Union maximum residue levels (EU-MRL). The Charm MRL BLTET test procedure was recently modified (dilution in buffer and longer incubation) by the manufacturers to be used with raw ewe and goat milk. To assess the Charm MRL BLTET test for the detection of β-lactams and tetracyclines in milk of small ruminants, an evaluation study was performed at Instituto de Ciencia y Tecnologia Animal of Universitat Politècnica de València (Spain). The test specificity and detection capability (CCβ) were studied following Commission Decision 2002/657/EC. Specificity results obtained in this study were optimal for individual milk free of antimicrobials from ewes (99.2% for β-lactams and 100% for tetracyclines) and goats (97.9% for β-lactams and 100% for tetracyclines) along the entire lactation period regardless of whether the results were visually or instrumentally interpreted. Moreover, no positive results were obtained when a relatively high concentration of different substances belonging to antimicrobial families other than β-lactams and tetracyclines were present in ewe and goat milk. For both types of milk, the CCβ calculated was lower or equal to EU-MRL for amoxicillin (4 µg/kg), ampicillin (4 µg/kg), benzylpenicillin (≤ 2 µg/kg), dicloxacillin (30 µg/kg), oxacillin (30 µg/kg), cefacetrile (≤ 63 µg/kg), cefalonium (≤ 10 µg/kg), cefapirin (≤ 30 µg/kg), desacetylcefapirin (≤ 30 µg/kg), cefazolin (≤ 25 µg/kg), cefoperazone (≤ 25 µg/kg), cefquinome (20 µg/kg), ceftiofur (≤ 50 µg/kg), desfuroylceftiofur (≤ 50µg/kg), and cephalexin (≤ 50 µg/kg). However, this test could neither detect cloxacillin nor nafcillin at or below EU-MRL (CCβ >30 µg/kg). The

  15. Minocycline and Doxycycline, but not Tetracycline, Mitigate Liver and Kidney Injury after Hemorrhagic Shock/Resuscitation*

    PubMed Central

    Kholmukhamedov, Andaleb; Czerny, Christoph; Hu, Jiangting; Schwartz, Justin; Zhong, Zhi; Lemasters, John J.

    2014-01-01

    Background Despite recovery of hemodynamics by fluid resuscitation after hemorrhage, development of the systemic inflammatory response and multiple organ dysfunction syndromes can nonetheless lead to death. Minocycline and doxycycline are tetracycline derivatives that are protective in models of hypoxic, ischemic and oxidative stress. Our Aim was to determine whether minocycline and doxycycline protect liver and kidney and improve survival in a mouse model of hemorrhagic shock and resuscitation. Methods Mice were hemorrhaged to 30 mm Hg for 3 h and then resuscitated with shed blood followed by half the shed volume of lactated Ringer's solution containing tetracycline (10 mg/kg), minocycline (10 mg/kg), doxycycline (5 mg/kg) or vehicle. For pre-plus post-treatment, drugs were administered intraperitoneally prior to hemorrhage followed by second equal dose in Ringer's solution after blood resuscitation. Blood and tissue were harvested after 6 h. Results Serum alanine aminotransferase (ALT) increased to 1988 and 1878 U/L after post-treatment with vehicle and tetracycline, respectively, whereas minocycline and doxycycline post-treatment decreased ALT to 857 and 863 U/L. Pre-plus post-treatment with minocycline and doxycycline also decreased ALT to 849 and 834 U/L. After vehicle, blood creatinine increased to 279 μM, which minocycline and doxycycline post-treatment decreased to 118 and 112 μM. Minocycline and doxycycline pre- plus post-treatment decreased creatinine similarly. Minocycline and doxycycline also decreased necrosis and apoptosis in liver and apoptosis in both liver and kidney, the latter assessed by TUNEL and caspase-3 activation. Lastly after 4.5 h of hemorrhage followed by resuscitation, minocycline and doxycycline (but not tetracycline) post-treatment improved 1-week survival from 38%(vehicle) to 69% and 67%, respectively. Conclusion Minocycline and doxycycline were similarly protective when given before as after blood resuscitation and might therefore

  16. Rhizodegradation of Sulfamethazine and Tetracycline and the Associated Impacts on Soil Microbial Activities

    USDA-ARS?s Scientific Manuscript database

    The use of sulfamethazine (SLF) and tetracycline (TC) to maintain animal health in the swine, poultry or cattle feedlot operations results in significant application of these veterinary pharmaceuticals to the landscape during grazing or manure disposal operations. Drinking water sources contaminated...

  17. Aspiration and tetracycline sclerotherapy of primary vaginal hydrocoele of testis in adults.

    PubMed

    Ali, Johar; Anwar, Waqas; Akbar, Mohammad; Akbar, Syed Ali; Zafar, Arshad

    2008-01-01

    Primary Vaginal Hydrocoele of Testis is a common condition which is primarily treated surgically. Many patients with Hydrocoele of testis are either not willing or are unfit for surgery. This study was done to know the safety, efficacy and out come of tetracycline induced sclerotherapy of Primary Vaginal Hydrocoele of Testis in adults. This quasi experimental study was done in Shahina Jamil Hospital, attached with Frontier Medical College and Ayub Teaching Hospital, Abbottabad from March 2006 to April, 2007. Thirty-seven patients with primary vaginal hydrocoele were included in the study. Aspiration and instillation of Tetracycline was done after spermatic cord block with 2% lignocaine. Procedure time, Peri and Post-procedure complications, number of injections for cure and patients' satisfaction with the procedure were recorded. Patients were discharged home 3 to 4 hours after the procedure and followed up after one week, one month, three months and six months. Direct admission and re-admissions were recorded. The mean age of patients was 47 years. Mean procedure time was 45 minutes. All patients were cured. Mild postoprocedure pain occurred in 12 (40%), moderate pain in 14 (46%) patients and severe pain in 4 (13.3%) patients. No patient developed haematoma or local infection. One patient (3.3%) had micturition problem. Two (6.6%) patients had minimal recurrence. One injection was sufficient for cure in all patients. 28 (93%) patients were satisfied while 2 (6.6%) patients were not satisfied with this procedure. No patient was admitted in the hospital after the procedure. Aspiration and injection of tetracycline in Primary vaginal Hydrocoele of Testis in adults is safe, effective and very economical procedure.

  18. Sorption and desorption of glyphosate, MCPA and tetracycline and their mixtures in soil as influenced by phosphate.

    PubMed

    Munira, Sirajum; Farenhorst, Annemieke

    2017-12-02

    Phosphate fertilizers and herbicides such as glyphosate and MCPA are commonly applied to agricultural land, and antibiotics such as tetracycline have been detected in soils following the application of livestock manures and biosolids to agricultural land. Utilizing a range of batch equilibrium experiments, this research examined the competitive sorption interactions of these chemicals in soil. Soil samples (0-15 cm) collected from long-term experimental plots contained Olsen P concentrations in the typical (13 to 20 mg kg -1 ) and elevated (81 to 99 mg kg -1 ) range of build-up phosphate in agricultural soils. The elevated Olsen P concentrations in field soils significantly reduced glyphosate sorption up to 50%, but had no significant impact on MCPA and tetracycline sorption. Fresh phosphate additions in the laboratory, introduced to soil prior to, or at the same time with the other chemical applications, had a greater impact on reducing glyphosate sorption (up to 45%) than on reducing tetracycline (up to 13%) and MCPA (up to 8%) sorption. The impact of fresh phosphate additions on the desorption of these three chemicals was also statistically significant, but numerically very small namely < 1% for glyphosate and tetracycline and 3% for MCPA. The presence of MCPA significantly reduced sorption and increased desorption of glyphosate, but only when MCPA was present at concentrations much greater than environmentally relevant and there was no phosphate added to the MCPA solution. Tetracycline addition had no significant effect on glyphosate sorption and desorption in soil. For the four chemicals studied, we conclude that when mixtures of phosphate, herbicides and antibiotics are present in soil, the greatest influence of their competitive interactions is phosphate decreasing glyphosate sorption and the presence of phosphate in solution lessens the potential impact of MCPA on glyphosate sorption. The presence of chemical mixtures in soil solution has an overall

  19. Ferulic acid destabilizes preformed {beta}-amyloid fibrils in vitro

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ono, Kenjiro; Hirohata, Mie; Yamada, Masahito

    2005-10-21

    Inhibition of the formation of {beta}-amyloid fibrils (fA{beta}), as well as the destabilization of preformed fA{beta} in the CNS, would be attractive therapeutic targets for the treatment of Alzheimer's disease (AD). We reported previously that curcumin (Cur) inhibits fA{beta} formation from A{beta} and destabilizes preformed fA{beta} in vitro. Using fluorescence spectroscopic analysis with thioflavin T and electron microscopic studies, we examined the effects of ferulic acid (FA) on the formation, extension, and destabilization of fA{beta} at pH 7.5 at 37 deg C in vitro. We next compared the anti-amyloidogenic activities of FA with Cur, rifampicin, and tetracycline. Ferulic acid dose-dependentlymore » inhibited fA{beta} formation from amyloid {beta}-peptide, as well as their extension. Moreover, it destabilized preformed fA{beta}s. The overall activity of the molecules examined was in the order of: Cur > FA > rifampicin = tetracycline. FA could be a key molecule for the development of therapeutics for AD.« less

  20. Serum inorganic fluoride and renal function in dogs after methoxyflurane anesthesia, tetracycline treatment, and surgical manipulation.

    PubMed

    Fleming, J T; Pedersoli, W M

    1980-12-01

    Effects of 2 hours of methoxyflurane-induced anesthesia in 25 dogs were determined by serum inorganic fluoride, serum urea nitrogen, serum creatinine, water intake, urine excretion, and urine specific gravity measurements; arterial concentrations of the anesthetic were also determined. The dogs were allotted to 5 groups (PTM, CTM, PTML, CTML, ML) of 5 dogs in each group and were anesthetized (M, in group designations) for 2 hours. The dogs were injected with chemically pure tetracycline or commercial tetracycline (PT and CT, in group designations) before, on the day of, and after anesthesia. In 3 groups, laparotomy (L, in group designations) was done; group ML did not receive tetracycline but a laparotomy was performed. Serum inorganic fluoride increased (P less than 0.05) in all groups 24 hours after anesthesia when compared with the base-line values; the highest mean serum concentration was 81.1 +/- 7.91 mumol/L (group PTM) and the lowest was 32.7 +/- 4.53 mumol/L (group PTML). There was no difference (P greater than 0.05) seen in serum urea nitrogen concentrations between groups. Methoxyflurane and tetracycline treatment caused no difference (P greater than 0.05) on serum concentrations of inorganic fluoride and urea nitrogen. Serum creatinine concentrations differed (P less than 0.05) only for groups PTM, CTM, PTML, and CTML vs group ML. Water intake reached peak at 48 hours after anesthesia. Arterial concentrations of methoxyflurane determined at 60 and 120 minutes of anesthesia indicated no difference (P greater than 0.05) among groups. Neither clinical nor laboratory signs of severe kidney dysfunction were detected in any of the experimental dogs during a 5-day observation period after anesthesia.

  1. Molecular evolution of tetracycline-resistance plasmids carrying TetM found in Neisseria gonorrhoeae from different countries.

    PubMed

    Gascoyne, D M; Heritage, J; Hawkey, P M; Turner, A; van Klingeren, B

    1991-08-01

    High level tetracycline resistant strains of Neisseria gonorrhoeae (TRNG) have been shown to carry a 40.6 kb (25.2 MDa) conjugative plasmid with a Class M tetracycline resistance determinant. Restriction endonuclease analysis mapping showed that there were at least two different TRNG plasmid types which were found in geographically distinct locations. The physical maps of these two plasmids were compared to a gonococcal conjugative plasmid which did not encode tetracycline resistance. The plasmid type which is endemic in the Netherlands was found to be closely related to the gonococcal conjugative plasmid, which supports the established hypothesis that the 40.6 kb plasmid has evolved by transposition of the TetM determinant into the conjugative plasmid. The plasmid found in the United States has either evolved by substantial divergent evolution or it results from a different transposition event. In the UK there have been isolations of TRNGs carrying either of the two plasmid types reflecting a flow of people both across the Atlantic and in Europe. It is possible that further TetM-containing plasmids will be found in N. gonorrhoeae paralleling the family of TEM beta-lactamase encoding plasmids already described.

  2. Effects of pH and cationic and nonionic surfactants on the adsorption of pharmaceuticals to a natural aquifer material.

    PubMed

    Hari, Ajai C; Paruchuri, Rajiv A; Sabatini, David A; Kibbey, Tohren C G

    2005-04-15

    A wide range of pharmaceutical compounds have been identified in the environment, and their presence is a topic of growing concern, both for human and ecological health. Adsorption to aquifer materials and sediments is an important factor influencing the fate and transport of pharmaceutical compounds in the environment. Surfactants and other amphiphiles are known to influence the adsorption of many compounds and may be present in the environment from wastewaters or other sources. The work described here examines the adsorption of four pharmaceutical compounds, acetaminophen, carbamazepine, nalidixic acid, and norfloxacin, in the presence of a natural aquifer material. Adsorption was studied as a function of pH and in the presence and absence of two surfactants, cetylpyridinium chloride (CPC), a cationic surfactant, and Tergitol NP9, an ethoxylated nonionic surfactant. In the absence of surfactants, results indicate a 1-2 orders of magnitude variation in adsorption affinity with changing pH for each of the two quinolone pharmaceuticals (nalidixic acid and norfloxacin) but no measurable adsorption for carbamazepine or acetaminophen. In the presence of surfactants, adsorption of acetaminophen and carbamazepine was enhanced to extents consistent with compound hydrophobicity, while adsorption of nalidixic acid and norfloxacin was not. At high pH values, the anionic species of nalidixic acid exhibited enhanced adsorption in the presence of the cationic surfactant, CPC.

  3. Gonococcal Resistance to β-Lactams and Tetracycline Involves Mutation in Loop 3 of the Porin Encoded at the penB Locus

    PubMed Central

    Gill, M. J.; Simjee, S.; Al-Hattawi, K.; Robertson, B. D.; Easmon, C. S. F.; Ison, C. A.

    1998-01-01

    penB is a chromosomal mutation that confers resistance to β-lactams and tetracyclines and reduced susceptibility to quinolones in Neisseria gonorrhoeae. It is linked to the porin gene (por) and requires the increased expression of an efflux pump due to mtr. Transformation of a susceptible gonococcus (strain H1) with chromosomal DNA from strain FA140 (penA mtr penB; porin serovar IB1) and conjugal transfer of a β-lactamase-expressing plasmid was used to produce isogenic strains for determination of equilibrium periplasmic penicillin concentrations by the method of Zimmermann and Rosselet (W. Zimmermann and A. Rosselet, Antimicrob. Agents Chemother. 12:368–372, 1977). In transformants with the Mtr and PenB phenotypes, equilibrium concentrations of penicillin were reduced. DNA sequence analysis of por from isogenic penB and penB+ transformants revealed 14 sequence differences; nine of these differences resulted in amino acid changes. Three amino acid changes were found in the putative gonococcal equivalent of the pore-constricting loop 3 of Escherichia coli OmpF. Two of these changes (Gly-101–Ala-102→Asp-Asp) result in an increased negative charge at this position in por loop 3. PCR products comprising the complete por gene from strain FA140 were transformed into strain H1-2 (penA mtr; porin serovar IB-3), with the resulting transformants having the antibiotic susceptibility phenotype associated with penB. penB-like mutations were found in loop 3 of clinical isolates of gonococci with chromosomally mediated resistance to penicillin. We conclude that penB is a mutation in loop 3 of por that reduces porin permeability to hydrophilic antibiotics and plays an important role in the development of chromosomally mediated resistance to penicillin and tetracycline in gonococci. PMID:9797206

  4. Characterization of resistance to tetracyclines and aminoglycosides of sheep mastitis pathogens: study of the effect of gene content on resistance.

    PubMed

    Lollai, S A; Ziccheddu, M; Duprè, I; Piras, D

    2016-10-01

    Mastitis causes economic losses and antimicrobials are frequently used for mastitis treatment. Antimicrobial resistance surveys are still rare in the ovine field and characterization of strains is important in order to acquire information about resistance and for optimization of therapy. Bacterial pathogens recovered in milk samples from mastitis-affected ewes were characterized for resistance to tetracyclines and aminoglycosides, members of which are frequently used antimicrobials in small ruminants. A total of 185 strains of staphylococci, streptococci, and enterococci, common mastitis pathogens, were tested for minimal inhibitory concentration (MIC) to tetracycline, doxycycline, minocycline, gentamicin, kanamycin, streptomycin, and for resistance genes by PCR. Effects of different tet genes arrangements on MICs were also investigated. Staphylococci expressed the lowest MIC for tetracycline and tet(K) was the most common gene recovered; tet(M) and tet(O) were also found. Gene content was shown to influence the tetracycline MIC values. Enterococci and streptococci showed higher MICs to tetracyclines and nonsusceptible strains always harboured at least one ribosomal protection gene (MIC above 8 μg ml(-1) ). Streptococci often harboured two or more tet determinants. As regards the resistance to aminoglycosides, staphylococci showed the lowest gentamicin and kanamycin median MIC along with streptomycin high level resistant (HLR) strains (MIC >1024 μg ml(-1) ) all harbouring str gene. The resistance determinant aac(6')-Ie-aph(2″)-Ia was present in few strains. Streptococci were basically nonsusceptible to aminoglycosides but neither HLR isolates nor resistance genes were detected. Enterococci revealed the highest MICs for gentamicin; two str harbouring isolates were shown to be HLR to streptomycin. Evidence was obtained for the circulation of antimicrobial-resistant strains and genes in sheep dairy farming. Tetracycline MIC of 64 μg ml(-1) and high

  5. Characterization of Antimicrobial Resistance Patterns and Detection of Virulence Genes in Campylobacter Isolates in Italy

    PubMed Central

    Di Giannatale, Elisabetta; Di Serafino, Gabriella; Zilli, Katiuscia; Alessiani, Alessandra; Sacchini, Lorena; Garofolo, Giuliano; Aprea, Giuseppe; Marotta, Francesca

    2014-01-01

    Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations. PMID:24556669

  6. Increased incidence of resistance to antimicrobials by urinary pathogens isolated at Tikur Anbessa Hospital.

    PubMed

    Wolday, D; Erge, W

    1997-04-01

    A retrospective analysis of 2209 urine samples submitted for culture to the Microbiology Laboratory of the Tikur Anbessa Hospital (TAH), Addis Ababa, between January 1992 and December 1994 was made. Significant bacteriuria (colony count > 10(5) colony forming units/ml urine) was detected in 672 (30%). Pure culture was obtained in 510 (23%) of all samples and polymicrobial growth was detected in the remaining 162 (7%). Gram-negative bacteria comprised 95% of all isolates. The commonest organisms being Escherichia coli (39%) and Klebsiella species (26%). Among the gram-positives, Staphylococcus aureus (57%) was the most common pathogen isolated. Most of the organisms were resistant to multiple drugs. Ampicillin, carbenicillin, chloramphenicol, tetracycline and trimethoprim-sulphamethoxazole were effective in less than 30% of all cases. There was also a significant resistance to cephalothin, gentamicin and kanamycin. Only nalidixic acid and nitrofurantoin were effective for most of the organisms. Compared to previous studies, there is an indication of reduced effectiveness of the commonly prescribed antibiotics. The rational use of drugs should be practiced in order to prevent the emergence of multi-drug resistant microorganisms.

  7. Characterization of antimicrobial resistance patterns and detection of virulence genes in Campylobacter isolates in Italy.

    PubMed

    Di Giannatale, Elisabetta; Di Serafino, Gabriella; Zilli, Katiuscia; Alessiani, Alessandra; Sacchini, Lorena; Garofolo, Giuliano; Aprea, Giuseppe; Marotta, Francesca

    2014-02-19

    Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis) and detection of virulence genes (sequencing and DNA microarray analysis). The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%), tetracycline (55.86%) and nalidixic acid (55.17%). Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations.

  8. Antimicrobial Resistance and Virulence-Associated Genes of Campylobacter spp. Isolated from Raw Milk, Fish, Poultry, and Red Meat.

    PubMed

    Raeisi, Mojtaba; Khoshbakht, Rahem; Ghaemi, Ezzat Allah; Bayani, Mahsan; Hashemi, Mohammad; Seyedghasemi, Navisa Sadat; Shirzad-Aski, Hesamaddin

    2017-10-01

    This study was designed and conducted to evaluate the frequency, antimicrobial resistance, and presence of six virulence-associated genes among thermophilic Campylobacters isolated from raw milk, poultry (chicken, turkey, and duck), fish, cattle, and sheep meat. Out of 590 samples, which were recovered from different origins, 141 (23.9%) samples were positive for Campylobacters. Campylobacter spp. was isolated in 40.8% (106/260), 14% (28/200), and 8.7% (7/80) of poultry meat, red meat, and milk samples, respectively. Antimicrobial susceptibility test indicated a high frequency of resistance to ciprofloxacin, tetracycline, and nalidixic acid among the isolates. Furthermore, prevalence of waaC, ciaB, and pldA genes were 91.7%, 86.7%, and 80.8%, respectively; and, none of the isolates harbored both wlaN and cgtB genes, simultaneously. Moreover, there was a weak correlation between antibiotics resistance and presence of the pathogen genes. However, the existence of Campylobacter spp. isolates in food animal products, with high resistance to antibiotics and several virulence gene possessions, is alarming and increases the attention to the widespread use of antibiotics.

  9. In vitro comparison of the activity of various antibiotics and drugs against new Taiwan isolates and standard strains of avian mycoplasma.

    PubMed

    Lin, M Y

    1987-01-01

    Twenty-nine antibiotics or drugs were incorporated individually into mycoplasma agar to evaluate their inhibitory activity against avian mycoplasmas: 100 recent Taiwan isolates of 7 serotypes and 10 standard strains of 7 serotypes were tested. All of the standard strains were very sensitive to erythromycin, chlorotetracycline, doxycycline, minocycline, and tetracycline, but the local isolates were highly resistant to these antibiotics. The drugs or antibiotics that possessed an MIC90 of 50 micrograms/ml or less against the local isolates were tiamulin (less than 0.4 micrograms/ml), lincospectin (2.7), josamycin (2.7), lincomycin (3.0), spectinomycin (4.8), tylosin (6.0), kanamycin (6.0), chloramphenicol (6.0), gentamicin (7.5), apramycin (24.5), doxycycline (27.4), minocycline (29.0), spiramycin (30.0), colistin (44.3), leucomycin (45.0), and streptomycin (50.0). The MIC90 of the other antibiotics or drugs was greater than 50 micrograms/ml. None of the isolates or strains were sensitive to nalidixic acid, ronidazole, penicillin, ampicillin, cephalexin, carbadox, or four sulfa drugs at a concentration about 5 times the therapeutic level.

  10. Genetic relatedness of a rarely isolated Salmonella: Salmonella enterica serotype Niakhar from NARMS animal isolates.

    PubMed

    Tankson, J D; Fedorka-Cray, P J; Jackson, C R; Headrick, M

    2006-02-01

    In the United States, Salmonella enterica serotype Niakhar is infrequently isolated. Between 1997 and 2000, the animal arm of the National Antimicrobial Resistance Monitoring System-Enteric Bacteria (NARMS) assayed a total of 22,383 Salmonella isolates from various animal sources (swine, cattle, chickens, turkeys, cats, horses, exotics and dogs) for antimicrobial susceptibility. Isolates originated from diagnostic and non-diagnostic submissions. To study the phenotypic and genotypic characteristics of Salmonella Niakhar. Only five (0.02%) of the 22,383 isolates were identified as Salmonella Niakhar. Antimicrobial resistance testing indicated that three isolates were pan-susceptible, one isolate was resistant to ampicillin and one isolate was resistant to ampicillin, chloramphenicol, ciprofloxacin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline and trimethoprim/sulfamethoxazole. RAPD-PCR analysis, PFGE and ribotyping indicated that two pan-susceptible isolates were genetically similar, whereas the three remaining isolates were genetically different. The one Salmonella Niakhar isolate that was multiresistant harboured a class I integron, intI1 and two large plasmids. This study represents the first report of a ciprofloxacin-resistant Salmonella isolate from the animal arm of NARMS.

  11. SEROTYPES AND ANTIMICROBIAL RESISTANCE OF SALMONELLA ENTERICA ISOLATED FROM PORK, CHICKEN MEAT AND LETTUCE, BANGKOK AND CENTRAL THAILAND.

    PubMed

    Niyomdecha, Nattamon; Mungkornkaew, Narissara; Samosornsuk, Worada

    2016-01-01

    Food of animal origins, particularly pork and chicken meat, has long been recognized as major sources of human salmonellosis. There have been recent reports of human salmonellosis outbreaks due to consumption of leafy green vegetables such as lettuce. In this study, 120 (40 pork, 40 chicken meat and 40 lettuce) samples were randomly collected from retail markets in Bangkok and central Thailand during June to August 2015 for Salmonella serotype identification and antimicrobial susceptibility testing. Salmonella was found in 82%, 62% and 20% of pork, chicken meat and lettuce samples, respectively. The top 5 most common Salmonella serotypes were Panama (15%), Schwarzengrund (12%), Rissen, Anatum, and Stanley (11% each), Albany (9%), and Indiana (8%). A high percentage of Salmonella isolated from food of animal origin were resistant to multiple antimicrobial drugs, including ampicillin, chloramphenicol, nalidixic acid, sulfamethoxazole-trimethoprim, and tetracycline. From antibiogram pattern analysis, the most common serotypes constituted isolates that were multidrug resistant. The study indicates that Salmonella was still present in various kinds of food and that certain serotypes have become predominant, a phenomenon not previously reported in Thailand.

  12. Laboratory monitoring of bacterial gastroenteric pathogens Salmonella and Shigella in Shanghai, China 2006-2012.

    PubMed

    Zhang, J; Wang, F; Jin, H; Hu, J; Yuan, Z; Shi, W; Yang, X; Meng, J; Xu, X

    2015-02-01

    In 2006 we initiated an enhanced laboratory-based surveillance of Salmonella and Shigella infections in Shanghai, China. A total of 4483 Salmonella and 2226 Shigella isolates were recovered from stool specimens by 2012. In 80 identified Salmonella serovars, Enteritidis (34·5%) and Typhimurium (26·2%) were the most common. Shigella (S.) sonnei accounted for 63·9% of human Shigella infections over the same time period, and replaced S. flexneri to become the primary cause of shigellosis since 2010. Overall, a high level of antimicrobial resistance was observed in Salmonella and Shigella, particularly to nalidixic acid, ampicillin, and tetracycline. Ciprofloxacin resistance was common in Salmonella Typhimurium (21·0%) and S. flexneri (37·6%). The cephalosporin resistance in both pathogens also increased over the years, ranging from 3·4% to 7·0% in Salmonella, and from 10·4% to 28·6% in Shigella. Resistance to multiple antimicrobials was also identified in a large number of the isolates. This study provides insight into the distribution of Salmonella and Shigella in diarrhoeal diseases.

  13. Long-term effect of tetracycline fibers on recurrent lesions in periodontal maintenance patients.

    PubMed

    Corsair, A

    1994-01-01

    Thirty-one patients with chronic adult periodontitis participated in this long-term private practice study. Sixty-one sites with moderate (4-6 mm, n = 21) or deep (> or = 7 mm, n = 40) periodontal pockets and bleeding on probing were treated with an antibiotic-releasing fiber, Actisite (Periodontal Therapeutic System) (tetracycline hydrochloride). Scaling/root planing (SRP) was performed on all teeth 3 weeks before start of the study, and on most teeth immediately before fiber insertion. Monolithic fibers loaded with 25% tetracycline hydrochloride were inserted in periodontal pockets, where they were retained for a mean of 6.7 days, at which point they were removed. Patients were evaluated at 1, 3, and 6 months after treatment; subgroups were also evaluated at normalized 12-month (10 patients, 20 sites) and 24-month (13 patients, 20 sites) time points. Sites showed a mean probing depth reduction of 2.5 mm at 6 months, and 2.2 mm at 24 months, with the deepest sites showing the greatest reduction. Bleeding on probing was 100% at baseline, 34% at 3 months, and 50% at 6 months. Attachment gains in 18 patients (25 sites) were 2.4 mm at 1 month, 3.0 mm at 3 months, and 2.5 mm at 6 months. Fibers were well tolerated; no adverse effects from treatment were noted. These results indicate that use of tetracycline fiber plus SRP clearly reduced the clinical signs of periodontal disease and maintained or improved attachment for up to 24 months in sites previously refractory to treatment.

  14. Biogas generation in anaerobic wastewater treatment under tetracycline antibiotic pressure

    PubMed Central

    Lu, Meiqing; Niu, Xiaojun; Liu, Wei; Zhang, Jun; Wang, Jie; Yang, Jia; Wang, Wenqi; Yang, Zhiquan

    2016-01-01

    The effect of tetracycline (TC) antibiotic on biogas generation in anaerobic wastewater treatment was studied. A lab-scale Anaerobic Baffled Reactor (ABR) with three compartments was used. The reactor was operated with synthetic wastewater in the absence of TC and in the presence of 250 μg/L TC for 90 days, respectively. The removal rate of TC, volatile fatty acids (VFAs), biogas compositions (hydrogen (H2), methane (CH4), carbon dioxide (CO2)), and total biogas production in each compartment were monitored in the two operational conditions. Results showed that the removal rate of TC was 14.97–67.97% in the reactor. The presence of TC had a large negative effect on CH4 and CO2 generation, but appeared to have a positive effect on H2 production and VFAs accumulation. This response indicated that the methanogenesis process was sensitive to TC presence, but the acidogenesis process was insensitive. This suggested that the presence of TC had less influence on the degradation of organic matter but had a strong influence on biogas generation. Additionally, the decrease of CH4 and CO2 generation and the increase of H2 and VFAs accumulation suggest a promising strategy to help alleviate global warming and improve resource recovery in an environmentally friendly approach. PMID:27341657

  15. Effect of Tetracycline Dose and Treatment Mode on Selection of Resistant Coliform Bacteria in Nursery Pigs

    PubMed Central

    Græsbøll, Kaare; Damborg, Peter; Mellerup, Anders; Herrero-Fresno, Ana; Larsen, Inge; Holm, Anders; Nielsen, Jens Peter; Christiansen, Lasse Engbo; Angen, Øystein; Ahmed, Shahana

    2017-01-01

    ABSTRACT This study describes the results of a randomized clinical trial investigating the effect of oxytetracycline treatment dose and mode of administration on the selection of antibiotic-resistant coliform bacteria in fecal samples from nursery pigs. Nursery pigs (pigs of 4 to 7 weeks of age) in five pig herds were treated with oxytetracycline for Lawsonia intracellularis-induced diarrhea. Each group was randomly allocated to one of five treatment groups: oral flock treatment with a (i) high (20 mg/kg of body weight), (ii) medium (10 mg/kg), or (iii) low (5 mg/kg) dose, (iv) oral pen-wise (small-group) treatment (10 mg/kg), and (v) individual intramuscular injection treatment (10 mg/kg). All groups were treated once a day for 5 days. In all groups, treatment caused a rise in the numbers and proportions of tetracycline-resistant coliform bacteria right after treatment, followed by a significant drop by the time that the pigs left the nursery unit. The counts and proportions of tetracycline-resistant coliforms did not vary significantly between treatment groups, except immediately after treatment, when the highest treatment dose resulted in the highest number of resistant coliforms. A control group treated with tiamulin did not show significant changes in the numbers or proportions of tetracycline-resistant coliforms. Selection for tetracycline-resistant coliforms was significantly correlated to selection for ampicillin- and sulfonamide-resistant strains but not to selection for cefotaxime-resistant strains. In conclusion, the difference in the dose of oxytetracycline and the way in which the drug was applied did not cause significantly different levels of selection of tetracycline-resistant coliform bacteria under the conditions tested. IMPORTANCE Antimicrobial resistance is a global threat to human health. Treatment of livestock with antimicrobials has a direct impact on this problem, and there is a need to improve the ways that we use antimicrobials in

  16. Effect of Tetracycline Dose and Treatment Mode on Selection of Resistant Coliform Bacteria in Nursery Pigs.

    PubMed

    Græsbøll, Kaare; Damborg, Peter; Mellerup, Anders; Herrero-Fresno, Ana; Larsen, Inge; Holm, Anders; Nielsen, Jens Peter; Christiansen, Lasse Engbo; Angen, Øystein; Ahmed, Shahana; Folkesson, Anders; Olsen, John Elmerdahl

    2017-06-15

    This study describes the results of a randomized clinical trial investigating the effect of oxytetracycline treatment dose and mode of administration on the selection of antibiotic-resistant coliform bacteria in fecal samples from nursery pigs. Nursery pigs (pigs of 4 to 7 weeks of age) in five pig herds were treated with oxytetracycline for Lawsonia intracellularis -induced diarrhea. Each group was randomly allocated to one of five treatment groups: oral flock treatment with a (i) high (20 mg/kg of body weight), (ii) medium (10 mg/kg), or (iii) low (5 mg/kg) dose, (iv) oral pen-wise (small-group) treatment (10 mg/kg), and (v) individual intramuscular injection treatment (10 mg/kg). All groups were treated once a day for 5 days. In all groups, treatment caused a rise in the numbers and proportions of tetracycline-resistant coliform bacteria right after treatment, followed by a significant drop by the time that the pigs left the nursery unit. The counts and proportions of tetracycline-resistant coliforms did not vary significantly between treatment groups, except immediately after treatment, when the highest treatment dose resulted in the highest number of resistant coliforms. A control group treated with tiamulin did not show significant changes in the numbers or proportions of tetracycline-resistant coliforms. Selection for tetracycline-resistant coliforms was significantly correlated to selection for ampicillin- and sulfonamide-resistant strains but not to selection for cefotaxime-resistant strains. In conclusion, the difference in the dose of oxytetracycline and the way in which the drug was applied did not cause significantly different levels of selection of tetracycline-resistant coliform bacteria under the conditions tested. IMPORTANCE Antimicrobial resistance is a global threat to human health. Treatment of livestock with antimicrobials has a direct impact on this problem, and there is a need to improve the ways that we use antimicrobials in livestock

  17. Effects of tetracycline on antibiotic resistance and removal of fecal indicator bacteria in aerated and unaerated leachfield mesocosms.

    PubMed

    Atoyan, Janet A; Patenaude, Erika L; Potts, David A; Amador, José A

    2007-09-01

    Antibiotics can be present in low concentrations in domestic wastewater, but little is known about their effect on bacteria in onsite wastewater treatment systems. Mesocosms, consisting of soil-filled lysimeters representing the leachfield of a septic system under aerated (AIR) and unaerated (LEACH) conditions, were used to study the effects of tetracycline addition (5 mg L(-1)) to septic tank effluent on tetracycline resistance in the fecal indicator bacteria Escherichia coli and fecal streptococci, and on their removal. The mesocosms were dosed with antibiotic for 10 days, and effects monitored for 52 days. The fraction of resistant bacteria in mesocosm drainage water relative to that in septic tank effluent, GammaRes, for E. coli ranged from 0 to 0.66 in the AIR treatment and from 0 to 3.32 in the LEACH treatment. For fecal streptococci, GammaRes ranged from 0 to 0.41 and from 0.63 to 1.06 in the AIR and LEACH treatments, respectively. No significant differences in antibiotic resistance of fecal indicator bacteria were observed among sampling dates in soil or water from either treatment. Tetracycline had no significant effect on removal of fecal indicator bacteria, which ranged from 99.9 to 100% for E. coli and from 95.9 to 100% for fecal streptococci. Our results suggest that short-term addition of tetracycline at environmentally-relevant concentrations is likely to have minimal consequences on pathogen removal from wastewater and development of antibiotic resistance among pathogenic bacteria in leachfield soil.

  18. Characterisation of penicillin and tetracycline resistance in Staphylococcus aureus isolated from bovine milk samples in Minas Gerais, Brazil.

    PubMed

    Martini, Caroline L; Lange, Carla C; Brito, Maria Avp; Ribeiro, João B; Mendonça, Letícia C; Vaz, Eliana K

    2017-05-01

    This Regional Research Communication describes the characterisation of ampicillin, penicillin and tetracycline resistance in Staphylococcus aureus isolated from bovine subclinical mastitis in Minas Gerais State, Brazil. Ninety S. aureus isolates from bovine mastitis exhibiting phenotypic resistance to ampicillin, penicillin and/or tetracycline were selected for this study. The minimum inhibitory concentration (MIC) of each antibiotic was determined using the E-Test® and the production of beta-lactamase was determined by cefinase disks. The resistance genes blaZ, tet(K), tet(L), tet(M), and tet(O) were investigated by PCR in all of the isolates. The MIC results classified 77, 83 and 71% of the isolates as resistant to ampicillin, penicillin and tetracycline, respectively. The MIC50 and MIC90 were, respectively, 1 and 2 µg/ml for ampicillin, 0·5 and 1 µg/ml for penicillin and 32 and 64 µg/ml for tetracycline. Eighty-six per cent of beta-lactamase producing isolates were detected. Of the 90 isolates investigated, 97% amplified blaZ, 84% amplified tet(K), 9% amplified tet(L), 2% amplified tet(M) and 1% amplified tet(O). Seventy-nine isolates (88%) showed blaZ together with at least one tet gene. S. aureus isolates showed high MIC50 and MIC90 values for the three antimicrobials. The blaZ and tet(K) genes were widespread in the herds studied, and most of the isolates harboured blaZ and tet(K) concomitantly.

  19. Multi-residue determination of seventeen sulfonamides and five tetracyclines in fish tissue using a multi-stage LC-ESI-MS/MS approach based on advanced mass spectrometric techniques.

    PubMed

    Dasenaki, Marilena E; Thomaidis, Nikolaos S

    2010-07-05

    A strategy was newly developed to rapidly screen seventeen sulfonamides and five tetracyclines in a single run from fish tissues using ultra-high performance liquid chromatography (UHPLC) coupled with comprehensive mass spectrometric approaches, including precursor-ion scan and data dependent scan. The product ions for precursor-ion scanning were selected by studying the MS/MS fragmentation of the analytes. All sulfonamides share the same diagnostic product ion at m/z 156 in positive MS/MS scan, while for tetracycline antibiotics the diagnostic product ion was proved to be at m/z 153.8. Further characterization of each compound was performed using a data dependent scan. Separation was performed on a Zorbax Eclipse Plus C18 column with a gradient elution using acetonitrile - 0.1% formic acid mobile phase at a flow rate of 0.1 mL min(-1). This approach has proven to be a powerful, highly selective, and sensitive tool for rapid screening and detection of non-targeted components in fish tissue and requires a minimum sample preparation such as one generic extraction step with MeOH:ACN 50:50 (v/v) acidified with 0.05% formic acid. The method has also been applied successfully to porcine and poultry meat. The validation of such a screening method was performed for the first time according to Commission Decision 2002/657/EC and satisfactory method performance characteristics were achieved. Copyright 2010 Elsevier B.V. All rights reserved.

  20. Synergistic Efficacy of Aedes aegypti Antimicrobial Peptide Cecropin A2 and Tetracycline against Pseudomonas aeruginosa

    PubMed Central

    Zheng, Zhaojun; Tharmalingam, Nagendran; Liu, Qingzhong; Kim, Wooseong; Fuchs, Beth Burgwyn; Zhang, Rijun; Vilcinskas, Andreas

    2017-01-01

    ABSTRACT The increasing prevalence of antibiotic resistance has created an urgent need for alternative drugs with new mechanisms of action. Antimicrobial peptides (AMPs) are promising candidates that could address the spread of multidrug-resistant bacteria, either alone or in combination with conventional antibiotics. We studied the antimicrobial efficacy and bactericidal mechanism of cecropin A2, a 36-residue α-helical cationic peptide derived from Aedes aegypti cecropin A, focusing on the common pathogen Pseudomonas aeruginosa. The peptide showed little hemolytic activity and toxicity toward mammalian cells, and the MICs against most clinical P. aeruginosa isolates were 32 to 64 μg/ml, and its MICs versus other Gram-negative bacteria were 2 to 32 μg/ml. Importantly, cecropin A2 demonstrated synergistic activity against P. aeruginosa when combined with tetracycline, reducing the MICs of both agents by 8-fold. The combination was also effective in vivo in the P. aeruginosa/Galleria mellonella model (P < 0.001). We found that cecropin A2 bound to P. aeruginosa lipopolysaccharides, permeabilized the membrane, and interacted with the bacterial genomic DNA, thus facilitating the translocation of tetracycline into the cytoplasm. In summary, the combination of cecropin A2 and tetracycline demonstrated synergistic antibacterial activity against P. aeruginosa in vitro and in vivo, offering an alternative approach for the treatment of P. aeruginosa infections. PMID:28483966

  1. Preparation of mucoadhesive oral patches containing tetracycline hydrochloride and carvacrol for treatment of local mouth bacterial infections and candidiasis.

    PubMed

    Obaidat, Rana M; Bader, Ammar; Al-Rajab, Wafa; Abu Sheikha, Ghassan; Obaidat, Aiman A

    2011-01-01

    The specific aim of this work was to prepare mucoadhesive patches containing tetracycline hydrochloride and carvacrol in an attempt to develop a novel oral drug delivery system for the treatment of mouth infections. The bilayered patches were prepared using ethyl cellulose as a backing layer and carbopol 934 as a matrix mucoadhesive layer. Patches were prepared with different loading amounts of tetracycline hydrochloride and carvacrol. The antimicrobial activity was assessed for the prepared patches using the disc-diffusion method against the yeast Candida albicans and five bacterial strains, including Pseudomonas aeruginosa, Escherichia coli, Bacillus cereus, Staphylococcus aureus, and Bacillus bronchispti. In this work, we highlighted the possibility of occurrence of a synergistic action between carvacrol and tetracycline. The best formulation was selected based on microbiological tests, drug release, ex-vivo mucoadhesive performance, and swelling index. Physical characteristics of the selected formulations were determined. These included pH, patch thickness, weight uniformity, content uniformity, folding endurance, and patch stability.

  2. The prevalence and epidemiology of plasmid-mediated penicillin and tetracycline resistance among Neisseria gonorrhoeae isolates in Guangzhou, China, 2002-2012.

    PubMed

    Zheng, Heping; Wu, Xingzhong; Huang, Jinmei; Qin, Xiaolin; Xue, Yaohua; Zeng, Weiying; Lan, Yinyuan; Ou, Jiangli; Tang, Sanmei; Fang, Mingheng

    2015-10-09

    Gonococcal antimicrobial resistance is a global problem. Different resistance plasmids have emerged and spread among the isolates of Neisseria gonorrhoeae worldwide and in China. We conducted this study to monitor the plasmid-mediated penicillin and tetracycline resistance among N. gonorrhoeae isolates in Guangzhou from 2002 to 2012. Consecutive isolates of N. gonorrhoeae were collected from outpatients with gonorrhea attending the STD clinic in Guangdong Provincial Centre for Skin Diseases and STIs Control and Prevention. Penicillinase-producing N. gonorrhoeae (PPNG) isolates were analyzed by the paper acidometric method. Plasmid-mediated resistance to tetracycline in N. gonorrhoeae (TRNG) isolates was screened by the agar plate dilution method. Plasmid types were determined for TRNG and PPNG isolates using polymerase chain reaction (PCR). Minimum inhibitory concentrations (MICs) to penicillin and tetracycline were detected by the agar plate dilution. Of 1378 consecutive N. gonorrhoeae isolates, 429 PPNG and 639 TRNG isolates were identified. The prevalence of PPNG, TRNG, and PPNG/TRNG increased from 18.3 to 47.1 % (χ (2) = 31.57, p < 0.001), from 29.4 to 52.1 % (χ (2) = 16.28, p < 0.001) and from 10.0 to 26.2 % (χ (2) = 10.46, p < 0.001) between 2002 and 2012, respectively. Genotyping of plasmids among PPNGs showed that the majority (93.7 %) of the isolates were the Asian type plasmids, while the African type plasmid emerged in 2008 and rapidly increased to 14.0 % in 2012 (χ (2) = 25.03, p < 0.001). For TRNGs, all 639 isolates carried the Dutch type plasmid. MICs of penicillin G and tetracycline persisted at high levels and the MIC90s were 32-fold higher than the resistant cutoff point over 11 years. The prevalence rates of penicillin- and tetracycline-resistant N. gonorrhoeae varied from 90.9 to 91.1 % and from 88.3 to 89.3 % during 2002 to 2012, respectively. Resistance to penicillin and tetracycline among N. gonorrhoeae

  3. Electrospun Zein/PCL Fibrous Matrices Release Tetracycline in a Controlled Manner, Killing Staphylococcus aureus Both in Biofilms and Ex Vivo on Pig Skin, and are Compatible with Human Skin Cells.

    PubMed

    Alhusein, Nour; Blagbrough, Ian S; Beeton, Michael L; Bolhuis, Albert; De Bank, Paul A

    2016-01-01

    To investigate the destruction of clinically-relevant bacteria within biofilms via the sustained release of the antibiotic tetracycline from zein-based electrospun polymeric fibrous matrices and to demonstrate the compatibility of such wound dressing matrices with human skin cells. Zein/PCL triple layered fibrous dressings with entrapped tetracycline were electrospun. The successful entrapment of tetracycline in these dressings was validated. The successful release of bioactive tetracycline, the destruction of preformed biofilms, and the viability of fibroblast (FEK4) cells were investigated. The sustained release of tetracycline from these matrices led to the efficient destruction of preformed biofilms from Staphylococcus aureus MRSA252 in vitro, and of MRSA252 and ATCC 25923 bacteria in an ex vivo pig skin model using 1 × 1 cm square matrices containing tetracycline (30 μg). Human FEK4 cells grew normally in the presence of these matrices. The ability of the zein-based matrices to destroy bacteria within increasingly complex in vitro biofilm models was clearly established. An ex vivo pig skin assay showed that these matrices, with entrapped tetracycline, efficiently kill bacteria and this, combined with their compatibility with a human skin cell line suggest these matrices are well suited for applications in wound healing and infection control.

  4. Application of nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, UV-Visible spectroscopy and kinetic modeling for elucidation of adsorption chemistry in uptake of tetracycline by zeolite beta.

    PubMed

    Kang, Jin; Liu, Huijuan; Zheng, Yu-Ming; Qu, Jiuhui; Chen, J Paul

    2011-02-01

    Extensive usage of tetracycline has resulted in its contamination in surface water and groundwater. The adsorption of tetracycline on zeolite beta was systematically investigated for the decontamination of the antibiotic polluted water in this study. Ninety percent of uptake by the zeolite beta occured in 0.25h, and the adsorption equilibrium was obtained within 3h, which was well described by an intraparticle diffusion model. The adsorption generally increased when pH was increased from 4.0 to 5.0, and then decreased significantly as the pH was further increased, which was caused by the pH-dependent speciation of tetracycline and surface charge of zeolite beta. Both Freundlich and Langmuir equations well described the adsorption isotherm. A thermodynamic analysis showed that the sorption process was spontaneous and endothermic. Aluminum atoms in the zeolite played a crucial role in the uptake; the adsorption increased with the increasing aluminum content in zeolite. The UV-Visible spectroscopy study showed that the spectra of tetracycline changed upon the interaction with zeolite beta, which could be ascribed to the formation of complexes of tetracycline and aluminum atoms in the zeolite surface. Nuclear magnetic resonance spectroscopy study further confirmed the participation of Al in the tetracycline adsorption. Fourier transform infrared spectroscopy studies showed that the amino functional groups in tetracycline were involved in the complexation with the zeolite surface. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Observations on the use of tetracycline and niacinamide as antipruritic agents in atopic dogs.

    PubMed Central

    Beningo, K E; Scott, D W; Miller, W H; Rothstein, E

    1999-01-01

    Tetracycline and niacinamide were administered in combination to 19 atopic dogs to determine their effectiveness in controlling pruritus. The pruritus was controlled successfully in only one dog. One dog experienced diarrhea that was severe enough to warrant stopping the medication. PMID:10200886

  6. EFFECT OF SINGLE AND REPEATED TETRACYCLINE ADMINISTRATION ON THE PHAGOCYTIC FUNCTION OF RETICULENDOTHELIAL SYSTEMS

    DTIC Science & Technology

    It was previously established that single administration of chlortetracycline and oxytetracycline to white mice stimulates the absorptive function of...upon repeated administration. The effect of single and repeated administration of chlortetracycline, tetracycline, and oxytetracycline on the absorptive function of mouse RES were studied.

  7. Antimicrobial resistance and phylogenetic groups in isolates of Escherichia coli from seagulls at the Berlengas nature reserve.

    PubMed

    Radhouani, H; Poeta, P; Igrejas, G; Gonçalves, A; Vinué, L; Torres, C

    2009-08-01

    Fifty-three faecal samples from yellow-legged gulls (Larus cachinnans) at the Berlengas nature reserve in Portugal were cultured on Levine agar plates not supplemented with antimicrobial agents, and one Escherichia coli colony was isolated and identified from each sample. The percentages of resistant isolates for each of the drugs were ampicillin (43.4 per cent), tetracycline (39.6 per cent), nalidixic acid (34.0 per cent), streptomycin (32.1 per cent), trimethoprim-sulfamethoxazole (SXT) (26.4 per cent), ciprofloxacin (18.9 per cent), chloramphenicol (18.9 per cent), gentamicin (7.5 per cent), tobramycin (7.5 per cent) amikacin (5.7 per cent) and amoxicillin-clavulanic acid (1.9 per cent). All the isolates were susceptible to cefoxitin, ceftazidime, cefotaxime, aztreonam and imipenem. The following resistance genes were detected: bla(TEM) (17 of 23 ampicillin-resistant isolates), tet(A) and/or tet(B) (18 of 21 tetracycline-resistant isolates), aadA (12 of 17 streptomycin-resistant isolates), cmlA (all chloramphenicol-resistant isolates), aac(3)-II with or without aac(3)-IV (all four gentamicin-resistant isolates), and sul1 and/or sul2 and/or sul3 (all 14 SXT-resistant isolates). The intI1 gene was detected in 10 of 14 SXT-resistant isolates, and three of them also contained class 2 integrons; four different gene cassette arrangements were identified among class 1 integrons (aadA, dfrA1+aadA1, dfrA12+orfF+aadA2 and sat+psp+aadA2) and one among the class 2 integrons (dfrA1+sat+aadA1). Ninety per cent of the isolates were included in the A or B1 phylogenetic groups.

  8. Generation of stable human cell lines with Tetracycline-inducible (Tet-on) shRNA or cDNA expression.

    PubMed

    Gomez-Martinez, Marta; Schmitz, Debora; Hergovich, Alexander

    2013-03-05

    A major approach in the field of mammalian cell biology is the manipulation of the expression of genes of interest in selected cell lines, with the aim to reveal one or several of the gene's function(s) using transient/stable overexpression or knockdown of the gene of interest. Unfortunately, for various cell biological investigations this approach is unsuitable when manipulations of gene expression result in cell growth/proliferation defects or unwanted cell differentiation. Therefore, researchers have adapted the Tetracycline repressor protein (TetR), taken from the E. coli tetracycline resistance operon(1), to generate very efficient and tight regulatory systems to express cDNAs in mammalian cells(2,3). In short, TetR has been modified to either (1) block initiation of transcription by binding to the Tet-operator (TO) in the promoter region upon addition of tetracycline (termed Tet-off system) or (2) bind to the TO in the absence of tetracycline (termed Tet-on system) (Figure 1). Given the inconvenience that the Tet-off system requires the continuous presence of tetracycline (which has a half-life of about 24 hr in tissue cell culture medium) the Tet-on system has been more extensively optimized, resulting in the development of very tight and efficient vector systems for cDNA expression as used here. Shortly after establishment of RNA interference (RNAi) for gene knockdown in mammalian cells(4), vectors expressing short-hairpin RNAs (shRNAs) were described that function very similar to siRNAs(5-11). However, these shRNA-mediated knockdown approaches have the same limitation as conventional knockout strategies, since stable depletion is not feasible when gene targets are essential for cellular survival. To overcome this limitation, van de Wetering et al.(12) modified the shRNA expression vector pSUPER(5) by inserting a TO in the promoter region, which enabled them to generate stable cell lines with tetracycline-inducible depletion of their target genes of

  9. Evaluation of commercially available biodegradable tetracycline fiber therapy in chronic periodontitis

    PubMed Central

    Sachdeva, Surinder; Agarwal, Vipin

    2011-01-01

    Background: Chronic periodontitis is an inflammatory disorder caused by dental plaque having mixed microbial flora. The different treatment modalities available to treat this disease are aimed at removal of micro-organisms from both hard and soft tissues. Systemic as well as local anti-microbial agents are helpful adjuncts in reducing microbes especially in inaccessible areas along with mechanical debridement therapy. Materials and Methods: The study was conducted in a split mouth design. Thirty-five patients having at least two non-adjacent sites in different quadrants with periodontal pockets ≥5 mm and with bleeding on probing at initial visit were selected. The selected sites were treated with both scaling and root planing plus tetracycline fibers or with scaling and root planing alone. Baseline and follow-up measurements included plaque index, gingival index, probing pocket depth, and clinical attachment level. Result: Both treatment modalities were affective in improving clinical parameters over three months’ observation period. The combined antimicrobial and mechanical debridement therapy has shown better results as compared with scaling and root planing alone. Conclusion: Application of tetracycline in modified collagen matrix following scaling and root planing might be beneficial in treatment of chronic periodontitis and improving periodontal parameters for 3-month duration. PMID:21976836

  10. The effects of pig manure application on the spread of tetracycline resistance in bulk and cucumber rhizosphere soils: a greenhouse experiment.

    PubMed

    Kang, Yijun; Hao, Yangyang; Xia, Dan; Shen, Min; Li, Qing; Hu, Jian

    2017-07-01

    It is important to understand the dynamics of tetracycline-resistant bacteria (TRB) and tetracycline resistance genes (TRGs) in bulk and rhizosphere soils for evaluating the spread of TRGs from pig manure to human. In this work, a greenhouse experiment was conducted to investigate the difference in abundance of TRB, tetracycline-resistant Escherichia coli (TRE), tetracycline-resistant Pseudomonas spp. (TRP), and TRGs between bulk and cucumber rhizosphere soils. The application of pig manure resulted in the long-term persistence of TRB, TRE, TRP, and TRGs in bulk soil and rhizosphere of cucumber for at least 65 days. Pig manure application dose was the major driving force in altering the abundances of TRB and TRE, whereas TRP was disturbed mainly by compartment (bulk soil or rhizosphere). Both TRE and the percentage of TRE in bulk and rhizosphere soils increased linearly with an increase in dose of pig manure. The exponential relationships between pig manure dose and TRP along with TRP percentage were also noted. There were significant differences in the relative abundances of TRGs between bulk and cucumber rhizosphere soils, suggesting the use of pig manure exerted a more lasting impact on the spread of TRGs in the rhizosphere than in the bulk soil.

  11. Efficacy of chloramphenicol, enrofloxacin, and tetracycline for treatment of experimental Rocky Mountain spotted fever in dogs.

    PubMed Central

    Breitschwerdt, E B; Davidson, M G; Aucoin, D P; Levy, M G; Szabados, N S; Hegarty, B C; Kuehne, A L; James, R L

    1991-01-01

    Dogs were experimentally inoculated with Rickettsia rickettsii to characterize the comparative efficacies of chloramphenicol, enrofloxacin, and tetracycline for the treatment of Rocky Mountain spotted fever (RMSF). All three antibiotics were equally effective in abrogating the clinical, hematologic, and vascular indicators of rickettsial infection. Antibiotic treatment for 24 h was sufficient to decrease the rickettsemia to levels below detection by Vero cell culture. Early treatment with all three antibiotics resulted in a similar decrease in antibody titer, but acute and convalescent serum samples taken at appropriate times would have still facilitated an accurate diagnosis of RMSF in all but one dog, which did not seroconvert. We conclude that chloramphenicol, enrofloxacin, and tetracycline are equally efficacious for treating experimental canine RMSF. PMID:1666498

  12. Electrospinning of PLGA/gum tragacanth nanofibers containing tetracycline hydrochloride for periodontal regeneration.

    PubMed

    Ranjbar-Mohammadi, Marziyeh; Zamani, M; Prabhakaran, M P; Bahrami, S Hajir; Ramakrishna, S

    2016-01-01

    Controlled drug release is a process in which a predetermined amount of drug is released for longer period of time, ranging from days to months, in a controlled manner. In this study, novel drug delivery devices were fabricated via blend electrospinning and coaxial electrospinning using poly lactic glycolic acid (PLGA), gum tragacanth (GT) and tetracycline hydrochloride (TCH) as a hydrophilic model drug in different compositions and their performance as a drug carrier scaffold was evaluated. Scanning electron microscopy (SEM) results showed that fabricated PLGA, blend PLGA/GT and core shell PLGA/GT nanofibers had a smooth and bead-less morphology with the diameter ranging from 180 to 460 nm. Drug release studies showed that both the fraction of GT within blend nanofibers and the core-shell structure can effectively control TCH release rate from the nanofibrous membranes. By incorporation of TCH into core-shell nanofibers, drug release was sustained for 75 days with only 19% of burst release within the first 2h. The prolonged drug release, together with proven biocompatibility, antibacterial and mechanical properties of drug loaded core shell nanofibers make them a promising candidate to be used as drug delivery system for periodontal diseases. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Sorption behavior of tetracyclines on suspended organic matters originating from swine wastewater.

    PubMed

    Lou, Yaoyin; Ye, Zhi-Long; Chen, Shaohua; Ye, Xin; Deng, Yujun; Zhang, Jianqiao

    2018-03-01

    Tetracyclines (TCs) discharged from livestock wastewater have aroused public concerns due to their pharmacological threats to ecosystems and human health. As an important medium in the wastewater, suspended organic matters (SOMs) play vital roles in antibiotics transport and degradation. However, limited information has been reported in the relevant literature. This study investigated TCs sorption behavior on SOM, withdrawn from swine wastewater. High TCs sorption capacities were detected, with the maximum values ranging from 0.337 to 0.679mg/g. Increasing pH and temperature led to the decline of sorption capacity. Results from three-dimensional excitation-emission matrix fluorescence spectroscopy and Fourier transform infrared spectrometry revealed that amide and carboxyl groups were the main functional groups for TCs adsorption. The interactions between SOM and TCs were clarified as predominated by hydrogen-bonding and cation-exchange in acid conditions, and electrostatic repulsion in neutral or alkaline conditions. Adsorption kinetics modeling was conducted, and a satisfactory fitting was achieved with the Freundlich equation. These results indicated that the adsorption process was a rather complex process, involving a combination of cation-exchange and hydrogen-bonding. The results will provide a better understanding of the capability of SOM for TCs transport and abatement in the wastewater treatment process. Copyright © 2017. Published by Elsevier B.V.

  14. Quantifying tetracycline resistance genes in swine waste anaerobic digester over a period of 100 days

    USDA-ARS?s Scientific Manuscript database

    Unregulated use of growth promoting antibiotics like Tetracyclines in agricultural feeds is becoming an increasing problem in antibiotic resistance. Undigested antibiotics leads to significant concentrations in livestock waste. These concentrations provide continuous selection pressure for the devel...

  15. Tetracycline Resistance and Presence of Tetracycline Resistance Determinants tet(V) and tap in Rapidly Growing Mycobacteria from Agricultural Soils and Clinical Isolates

    PubMed Central

    Kyselková, Martina; Chron̂áková, Alica; Volná, Lucie; Nêmec, Jan; Ulmann, Vít; Scharfen, Josef; Elhottová, Dana

    2012-01-01

    Rapidly growing mycobacteria (RGM) inhabit soil and water but certain strains represent a health risk for human and animals. Both clinical and soil RGM may be under selection pressure for resistance to tetracycline (TET) antibiotics, since tetracyclines are administrated to humans and farm animals, and TET residues enter soil through manuring; however, resistance to TET and the presence of TET-resistance genes have been assessed only in clinical isolates. We were therefore interested in comparing soil and clinical RGM in terms of TET resistance and the presence of TET-resistance genes. We used 44 RGM from grasslands with different exposure to animal manure, and 38 clinical RGM from Czech hospitals. There was no difference between the clinical and soil isolates in TET resistance, with >50% resistant isolates in both groups. otr(A), otr(B), tet(K), tet(L) or tet(M) were not detected in any soil or clinical isolate. In contrast, most isolates harbored tet(V) and tap, both encoding mycobacterial efflux pumps, including species where these genes have never been evidenced before. The phylogeny of tet(V) correlated with isolates’ BOX-PCR profiles, suggesting that this gene evolved along with mycobacterial genomes as a part of the intrinsic resistome. In certain cases, tet(V) and/or tap were found in TET-sensitive isolates, or inversely, were not found in resistant strains. Concluding, intrinsic efflux pumps may be more important for TET resistance than horizontally transferred genes in both soil and clinical RGM. Their simple presence, however, does not attest to resistance, and therefore their diversity, function and expression merit further research. PMID:22673307

  16. Occurrence of porphyromonas gingivalis and its antibacterial susceptibility to metronidazole and tetracycline in patients with chronic periodontitis.

    PubMed

    Gamboa, Fredy; Acosta, Adriana; García, Dabeiba-Adriana; Velosa, Juliana; Araya, Natalia; Ledergerber, Roberto

    2014-01-01

    Chronic periodontitis is a multifactorial infectious disease associated with Gram-negative strict anaerobes which are immersed in the subgingival biofilm. Porphyromonas gingivalis, an important periodontal pathogen, is frequently detected in patients with chronic periodontitis. Although isolates of P. gingivalis tend to be susceptible to most antimicrobial agents, relatively little information is available on its in vitro antimicrobial susceptibility. The aim of this study was to determine the frequency of P. gingivalis in patients with chronic periodontitis and to assess antimicrobial susceptibility in terms of minimum inhibitory concentration (MIC) of clinical isolates to metronidazole and tetracycline. A descriptive, observational study was performed including 87 patients with chronic periodontitis. Samples were taken from the periodontal pocket using paper points, which were placed in thioglycollate broth. Samples were incubated for 4 hours at 37°C in anaerobic conditions and finally replated on Wilkins-Chalgren anaerobic agar (Oxoid). Bacteria were identified using the RapIDTMANAII system (Remel) and antimicrobial susceptibility was determined with the M.I.C. Evaluator test (MICE, Oxoid). P. gingivalis was identified in 30 of the 87 patients with chronic periodontitis, which represents a frequency of 34.5%. All 30 isolates (100%) were sensitive to metronidazole, with MIC values ranging from 0015-4ug/ml. Regarding tetracycline, 27 isolates (90%) were sensitive, with MIC values ranging from <0.015 to 4 ug /ml, the remaining three isolates (10%) were resistant to tetracycline with MIC values of 8ug/ ml. There was no statistically significant difference in age, gender, pocket depth, clinical attachment level and severity of periodontitis between the group of patients with chronic periodontitis and P. gingivalis and the group of patients with chronic periodontitis without P. gingivalis. In conclusion, P. gingivalis was found at a frequency of 34.5% in patients

  17. Hairy roots of Helianthus annuus: a model system to study phytoremediation of tetracycline and oxytetracycline.

    PubMed

    Gujarathi, Ninad P; Haney, Bryan J; Park, Heidi J; Wickramasinghe, S Ranil; Linden, James C

    2005-01-01

    The release of antibiotics to the environment has to be controlled because of serious threats to human health. Hairy root cultures of Helianthus annuus (sunflower), along with their inherent rhizospheric activity, provide a fast growing, microbe-free environment for understanding plant-pollutant interactions. The root system catalyzes rapid disappearance of tetracycline (TC) and oxytetracycline (OTC) from aqueous media, which suggests roots have potential for phytoremediation of the two antibiotics in vivo. In addition, in vitro modifications of the two antibiotics by filtered, cell- and microbe-free root exudates suggest involvement of root-secreted compounds. The modification is confirmed from changes observed in UV spectra of exudate-treated OTC. Modification appears to be more dominant at the BCD chromophore of the antibiotic molecule. Kinetic analyses dismiss direct enzyme catalysis; the modification rates decrease with increasing OTC concentrations. The rates increase with increasing age of cultures from which root exudates are prepared. The decrease in modification rates upon addition of the antioxidant ascorbic acid (AA) suggests involvement of reactive oxygen species (ROS) in the antibiotic modification process.

  18. Quinolones and tetracyclines in aquaculture fish by a simple and rapid LC-MS/MS method.

    PubMed

    Guidi, Letícia Rocha; Santos, Flávio Alves; Ribeiro, Ana Cláudia S R; Fernandes, Christian; Silva, Luiza H M; Gloria, Maria Beatriz A

    2018-04-15

    The determination of antimicrobials in aquaculture fish is important to ensure food safety. Therefore, simple and fast multiresidue methods are needed. A liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of 14 antimicrobials (quinolones and tetracyclines) in fish. Antimicrobials were extracted with trichloroacetic acid and chromatographic separation was achieved with a C18 column and gradient elution (water and acetonitrile). The method was validated (Decision 2002/657/EC) and it was fit for the purpose. Linearities were established in the matrix and the coefficients of determination were ≥0.98. The method was applied to Nile tilapia and rainbow trout (n = 29) and 14% of them contained enrofloxacin at levels above the limit of quantification (12.53-19.01 µg.kg -1 ) but below the maximum residue limit (100 µg.kg -1 ). Even though prohibited in Brazil and other countries, this antimicrobial reached fish. Measures are needed to ascertain the source of this compound to warrant human safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Enhancing anaerobic digestion and methane production of tetracycline wastewater in EGSB reactor with GAC/NZVI mediator.

    PubMed

    Zhang, Zhaohan; Gao, Peng; Cheng, Jiaqi; Liu, Guohong; Zhang, Xiaoqi; Feng, Yujie

    2018-06-01

    Packing nano mediators into anaerobic system is an attractive technology to strengthen refractory pollutant removal and methane production from wastewater, but is limited by the drawbacks such as easy loss and poor mass transfer. In this study, GAC/NZVI mediator was added into EGSB reactor to investigate the enhancement effects and mechanism for anaerobic digestion of tetracycline wastewater and its impacts on microbial community structure. The results indicated that GAC/NZVI could enhance COD and TOC removal by 12.1% and 10.3%, while have no evident influence on tetracycline removal and sulfide production. The biogas production and methane content were increased by 21.2% and 26.9%, respectively. GAC/NZVI addition resulted in formation of densely packed aggregates, and evidently increased the electrical conductivity and EPS content in sludge. Fe content in sludge was 20.43% with the loss of only 5.4% during 34 d operation. Microbial community analysis revealed that GAC/NZVI addition could both increase the Chao 1 richness index and Shannon diversity index of bacteria and archaea. It was notable that total methanogens contents increased from 74.7% to 81.74% at genera level, resulting in higher methane production, while Treponema increase might promote the degradation of tetracycline and its metabolite, leading to higher COD removal. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Magnetic solid-phase extraction of tetracyclines using ferrous oxide coated magnetic silica microspheres from water samples.

    PubMed

    Lian, Lili; Lv, Jinyi; Wang, Xiyue; Lou, Dawei

    2018-01-26

    A novel magnetic solid-phase extraction approach was proposed for extraction of potential residues of tetracyclines (TCs) in tap and river water samples, based on Fe 3 O 4 @SiO 2 @FeO magnetic nanocomposite. Characterized results showed that the received Fe 3 O 4 @SiO 2 @FeO had distinguished magnetism and core-shell structure. Modified FeO nanoparticles with an ∼5 nm size distribution were homogeneously dispersed on the surface of the silica shell. Owing to the strong surface affinity of Fe (II) toward TCs, the magnetic nanocomposite could be applied to efficiently extract three TCs antibiotics, namely, oxytetracycline, tetracycline and chlortetracycline from water samples. Several factors, such as sorbent amount, pH condition, adsorption and desorption time, desorption solvent, selectivity and sample volume, influencing the extraction performance of TCs were investigated and optimized. The developed method showed excellent linearity (R > 0.9992) in the range of 0.133-333 μg L -1 , under optimized conditions. The limits of detection were between 0.027 and 0.107 μg L -1 for oxytetracycline, tetracycline and chlortetracycline, respectively. The feasibility of this method was evaluated by analysis of tap and river water samples. The recoveries at the spiked concentration levels ranged from 91.0% to 104.6% with favorable reproducibility (RSD < 4%). Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Removal of tetracyclines, sulfonamides, and quinolones by industrial-scale composting and anaerobic digestion processes.

    PubMed

    Liu, Hang; Pu, Chengjun; Yu, Xiaolu; Sun, Ying; Chen, Junhao

    2018-02-15

    This study evaluated and compared the removal of antibiotics by industrial-scale composting and anaerobic digestion at different seasons. Twenty compounds belonged to three classes of widely used veterinary antibiotics (i.e., tetracyclines, sulfonamides, and quinolones) were investigated. Results show that of the three groups of antibiotics, tetracyclines were dominant in swine feces and poorly removed by anaerobic digestion with significant accumulation in biosolids, particularly in winter. Compared to that in winter, a much more effective removal (> 97%) by anaerobic digestion was observed for sulfonamides in summer. By contrast, quinolones were the least abundant antibiotics in swine feces and exhibited a higher removal by anaerobic digestion in winter than in summer. The overall removal of antibiotics by aerobic composting could be more than 90% in either winter or summer. Nevertheless, compost products from livestock farms in Beijing contained much higher antibiotics than commercial organic fertilizers. Thus, industrial composting standards should be strictly applied to livestock farms to further remove antibiotics and produce high quality organic fertilizer.

  2. A case of vesicular cutaneous lupus erythematosus in a Border collie successfully treated with topical tacrolimus and nicotinamide-tetracycline.

    PubMed

    Lehner, Georg M; Linek, Monika

    2013-12-01

    Canine vesicular cutaneous lupus erythematosus (VCLE) is an autoimmune skin disease of the Shetland sheepdog and rough collie, which manifests as an erosive dermatitis of sparsely haired skin of the ventrum and concave pinnae. Reported treatment consists of immunosuppression with glucocorticoids alone or in combination with azathioprine, but successful treatment is unpredictable. To report on the treatment of VCLE in a Border collie dog with topical 0.1% tacrolimus and nicotinamide in combination with tetracycline. An 8-year-old male neutered Border collie was presented with multiple coalescing erosions on the ventral abdomen, groin and axillae and ulceration on the oral commissures. Clinical presentation, routine diagnostics, histology and immunohistochemistry were consistent with VCLE. Remission was achieved with topical 0.1% tacrolimus and combination therapy of nicotinamide and tetracycline. This dog responded well to treatment with topical 0.1% tacrolimus, nicotinamide-tetracycline and sun avoidance. Complete remission was achieved after 2.5 months, and the dog was lesion free during a 1 year follow-up period. © 2013 ESVD and ACVD.

  3. Bifunctional composite from spent "Cyprus coffee" for tetracycline removal and phenol degradation: Solar-Fenton process and artificial neural network.

    PubMed

    Oladipo, Akeem Adeyemi; Abureesh, Mosab Ali; Gazi, Mustafa

    2016-09-01

    Removals of tetracycline and photocatalytic degradation of phenol by Fe3O4/coffee residue (MCC) were investigated. Brunauer-Emmett-Teller (BET), vibrating sample magnetometer (VSM) and Boehm titration were employed to characterize MCC. Artificial neural network (ANN) model was developed to predict the tetracycline (TC) concentration in the column effluent. Maximum tetracycline adsorption capacity of 285.6mg/g was observed in a batch system. High removal efficiency (87%) was obtained at 3.3mL/min flow rate, 8.0cm bed height and 50mg/L influent TC concentration in a column system. Complete degradation of phenol by solar-Fenton was attained at 60min irradiation time. Total organic carbon (TOC) removal increased to 63.3% in the presence of 1.0g/L MCC, 1.2g/L H2O2 and solar irradiation. MCC showed remarkable potential to remove antibiotics from wastewater even in the presence of heavy metal (Ni(2+)) via magnetic separation. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Antimicrobial susceptibility patterns of Shigella isolates in Foodborne Diseases Active Surveillance Network (FoodNet) sites, 2000-2010.

    PubMed

    Shiferaw, Beletshachew; Solghan, Suzanne; Palmer, Amanda; Joyce, Kevin; Barzilay, Ezra J; Krueger, Amy; Cieslak, Paul

    2012-06-01

    Treatment of shigellosis with appropriate antimicrobial agents shortens duration of illness and bacterial shedding, but resistance to commonly used agents is increasing. We describe resistance patterns among Shigella isolates in the United States with use of linked data from the Foodborne Diseases Active Surveillance Network (FoodNet) and National Antimicrobial Resistance Monitoring System (NARMS). FoodNet sites send every 20th Shigella isolate to the NARMS laboratory for susceptibility testing. During 2000-2010, the NARMS laboratory tested 1376 Shigella isolates from FoodNet sites. Of 1118 isolates (81%) linked to FoodNet, 826 (74%) were resistant to ampicillin, 649 (58%) to streptomycin, 402 (36%) to trimethoprim-sulfamethoxazole (TMP-SMX), 355 (32%) to sulfamethoxazole-sulfisoxazole, 312 (28%) to tetracycline, 19 (2%) to nalidixic acid, and 6 (0.5%) to ciprofloxacin. The proportion of Shigella isolates with resistance to TMP-SMX was 40% among white persons, 58% among Hispanic persons, and 75% among persons with a history of international travel. Resistance to at least TMP-SMX and ampicillin was present in 25% of isolate, and 5% were resistant to ampicillin, TMP-SMX, and chloramphenicol. Overall, 5% of isolates showed multidrug resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole-sulfisoxazole, and tetracycline, including 49 Shigella flexneri (33%) and 3 Shigella sonnei (0.3%) isolates. Male individuals were more likely than female individuals to be infected with a multidrug-resistant strain (7% versus 3%; P < .01). Antimicrobial resistance differed by race, ethnicity, age, travel, and species. Resistance to commonly used antibiotics is high; therefore, it is important to look at the susceptibility pattern before starting treatment.

  5. Antibiotic susceptibility patterns and prevalence of group B Streptococcus isolated from pregnant women in Misiones, Argentina

    PubMed Central

    Quiroga, M.; Pegels, E.; Oviedo, P.; Pereyra, E.; Vergara, M.

    2008-01-01

    This study was performed to determine the susceptibility patterns and the colonization rate of Group B Streptococcus (GBS) in a population of pregnant women. From January 2004 to December 2006, vaginal-rectal swabs were obtained from 1105 women attending Dr. Ramón Madariaga Hospital, in Posadas, Misiones, Argentina. The carriage rate of GBS among pregnant women was 7.6%. A total of 62 GBS strains were randomly selected for in vitro susceptibility testing to penicillin G, ampicillin, tetracycline, levofloxacin, gatifloxacin, ciprofloxacin, quinupristin-dalfopristin, linezolid, vancomycin, rifampicin, trimethoprim- sulfametoxazol, nitrofurantoin, gentamicin, clindamycin and erythromycin, and determination of resistance phenotypes. No resistance to penicillin, ampicillin, quinupristin-dalfopristin, linezolid, and vancomycin was found. Of the isolates examined 96.8%, 98.3%, 46.8%, and 29.0% were susceptible to rifampicin, nitrofurantoin, trimethoprim-sulfametoxazol and tetracycline, respectively. Rank order of susceptibility for the quinolones was: gatifloxacin (98.4%) > levofloxacin (93.5%) > ciprofloxacin (64.5%). The rate of resistance to erythromycin (9.7%) was higher than that of other reports from Argentina. High-level resistance to gentamicin was not detected in any of the isolates. Based on our finding of 50% of GBS isolates with MIC to gentamicin equal o lower than 8 μg/ml, a concentration used in one of the selective media recommended for GBS isolation, we suggested, at least in our population, the use of nalidixic acid and colistin in selective media with the aim to improve the sensitivity of screening cultures for GBS carriage in women. PMID:24031210

  6. Antimicrobial resistance of Escherichia coli isolated in newly-hatched chickens and effect of amoxicillin treatment during their growth.

    PubMed

    Jiménez-Belenguer, Ana; Doménech, Eva; Villagrá, Arantxa; Fenollar, Alejandro; Ferrús, Maria Antonia

    2016-08-01

    The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. However, other factors may also play a part, and in particular vertical spread between the generations has been suggested to be an important transmission pathway. The objective of this paper was to determine the resistance patterns of Escherichia coli isolated from newly-hatched chickens as well as to study the antibiotic pressure effect when amoxicillin was administered during their growing period. With this aim, meconium from 22 one-day-old Ross chickens was analysed. In addition, during their growth period, amoxicillin treatments at days 7, 21 and 35 were carried out. Results showed a high number of E. coli-resistant strains were isolated from the treated one-day-old chickens, and were the highest for β-lactams group, followed by quinolone and tetracyclines. After treatment with amoxicillin, the highest percentage of resistances were detected for this antibiotic compared to the others analysed, with significant differences in resistance percentages between control and treated broilers detected in relation to ampicillin, cephalothin, streptomycin, kanamycin, gentamicin, chloramphenicol and tetracycline. Differences in resistances to ciprofloxacin and nalidixic acid between control and treated animals were not observed and there was lack of resistance for amikacin and ceftriaxone. These results suggest the possibility of vertical transmission of resistant strains to newly-hatched chicks from parent flocks, and seem to indicate that the treatment with amoxicillin increased the resistance of E. coli to other antibiotics.

  7. A novel green chemistry method for nonaqueous extraction and high-performance liquid chromatography detection of first-, second-, and third-generation tetracyclines, 4-epitetracycline, and tylosin in animal feeds.

    PubMed

    Granados-Chinchilla, Fabio; Sánchez, Jorge; García, Fernando; Rodríguez, César

    2012-07-25

    Although tetracyclines and macrolides are common additives for animal nutrition, methods for their simultaneous determination in animal feeds are nonexistent. By coupling an organic extraction and solid-phase extraction cleanup to a high-performance liquid chromatography separation and a nonaqueous postcolumn derivatization, we succeeded in detecting from 0.2 to 24.0 μg kg(-1) of tetracycline, oxytetracycline, chlortetracycline, doxycycline, tigecycline, and 4-epitetracycline in this complex and heterogeneous matrix. Minocycline and tylosin could also be detected with our procedure, but using UV spectrophotometry (1.5 ≤ LOD ≤ 1.9 mg kg(-1)). Linear responses with correlation coefficients between 0.996 and 0.999 were obtained for all analytes in the 0.5-10 mg kg(-1) concentration range. Average recoveries between 59 and 97% and between 98 and 102% were obtained for the tetracyclines and tylosin, respectively. Replicate standard deviations were typically below 5%. When this method was applied to 20 feeds marketed in Costa Rica, we detected labeling inconsistencies, banned mixtures of tetracyclines, and tetracycline concentrations that contravene international regulation.

  8. Degree of time dependency of kinetic coefficient as a function of adsorbate concentration; new insights from adsorption of tetracycline onto monodispersed starch-stabilized magnetic nanocomposite.

    PubMed

    Okoli, Chukwunonso P; Ofomaja, Augustine E

    2018-07-15

    The realization that the observed kinetic coefficient (k obs ) varies with time in most real-time adsorption system, as against the constant value conceived in the most widely-applied adsorption kinetic models, have attracted much attention in recent time. Understanding the factors that control the extent/degree of time dependency (otherwise known as fractal-like kinetics), is therefore central in taking manipulative advantage of this phenomenon in critical adsorption applications. This study therefore deployed non-fractal-like and fractal-like kinetic approach to study the adsorption of tetracycline on monodispersed starch-stabilized magnetite nanocomposite (MSM). MSM was synthesized by in-situ coprecipitation of magnetite in the presence of starch, and successfully characterized with classical solid-state techniques. Isotherm studies indicated that MSM has heterogenous surface adsorption sites. Equilibrium and kinetic data indicated the existence of π-cation interaction as the underlying mechanism, while pH study revealed that tetracycline was adsorbed in its zwitterion form. Though the non-fractal kinetic models exhibited some level of relevance in explaining the tetracycline adsorption interactions, the best fitting of the fractal-like pseudo second order model to the adsorption kinetic data, indicated that the real-time adsorption kinetics occurred in fractal-like manner. The study also revealed that the degree of time dependency of k obs had negative correlation with the initial tetracycline concentration. Apart from developing a low-cost strategy for addressing tetracycline water pollution, the result of this study serves a positive step towards gaining manipulative control of adsorption mechanism in potential application of MSM for targeted drug delivery and controlled release of tetracycline antibiotics. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Assessing potential human health hazards and benefits from subtherapeutic antibiotics in the United States: tetracyclines as a case study.

    PubMed

    Cox, Louis Anthony Tony; Popken, Douglas A

    2010-03-01

    Many scientists, activists, regulators, and politicians have expressed urgent concern that using antibiotics in food animals selects for resistant strains of bacteria that harm human health and bring nearer a "postantibiotic era" of multidrug resistant "super-bugs." Proposed political solutions, such as the Preservation of Antibiotics for Medical Treatment Act (PAMTA), would ban entire classes of subtherapeutic antibiotics (STAs) now used for disease prevention and growth promotion in food animals. The proposed bans are not driven by formal quantitative risk assessment (QRA), but by a perceived need for immediate action to prevent potential catastrophe. Similar fears led to STA phase-outs in Europe a decade ago. However, QRA and empirical data indicate that continued use of STAs in the United States has not harmed human health, and bans in Europe have not helped human health. The fears motivating PAMTA contrast with QRA estimates of vanishingly small risks. As a case study, examining specific tetracycline uses and resistance patterns suggests that there is no significant human health hazard from continued use of tetracycline in food animals. Simple hypothetical calculations suggest an unobservably small risk (between 0 and 1.75E-11 excess lifetime risk of a tetracycline-resistant infection), based on the long history of tetracycline use in the United States without resistance-related treatment failures. QRAs for other STA uses in food animals also find that human health risks are vanishingly small. Whether such QRA calculations will guide risk management policy for animal antibiotics in the United States remains to be seen.

  10. MOLECULAR CHARACTERISATION AND ANTIMICROBIAL RESISTANCE PATTERNS OF ESCHERICHIA COLI ISOLATES FROM GOATS SLAUGHTERED IN PARTS OF KENYA.

    PubMed

    Njoroge, S; Muigai, A W T; Njiruh, P N; Kariuki, S

    2013-03-01

    To determine the antibiotic resistance patterns of pathogenic Escherichia coli on goat meat carcass at Huruma and Kiserian abattoirs in Kenya. Laboratory based study. Huruma and Kiserian abattoirs in Kenya, 400 slaughtered goats inspected by veterinary health officers and approved for human consumption. A Total of 400 slaughtered goats which were inspected by veterinary health officers and approved for human consumption were sampled from Huruma and Kiserian abattoir. Goat carcass swabs were collected by passing each swab tissue on four parts of the carcass mainly neck, right and left forelimbs, right and left hind limbs, and brisket. A total of 54 E. coli isolates were isolated and confirmed to be pathogenic. The percentage of isolates resistant to various microbial agents was recorded as follows: ampicillin (26 %), amoxycillin-clavulanic acid (17%), tetracycline (15%), chroramphenicol (4%), and ceftrixone (2% each). All Escherichia coli isolates were susceptible to gentamicin sulphamethaxazole-trimethomprin, kanamycin, cetriazididine (CAZ, 30pg), ciproxacin, nalidixic acid and chloramphenicol. Isolates were resistant to one or more of the antibiotics tested. Among the drugs tested, resistance was more frequently observed against ampicillin, amoxycillin-clavulanic acid, tetracycline, ceftrixone and chroramphenicol antibiotics. Among the isolates 26(48%) were positive for the stx1 gene, 19(35%) had the eae gene, 10(19%) possessed est gene,while 8(15%) harboured elt gene. Overall five isolates (10%) possessed aspu gene and two (4%) had aggR gene. No isolate possessed ipah gene. This study demonstrated that there is a significant level of antimicrobial resistance in pathogenic E. coli isolated from goat meat from Huruma and Kiserian abattoir. This indicates that goat meat from abattoirs could pose a risk of transmission of pathogenic antibiotic resistant strains to human. Poor hygienic standards and indiscriminate use of antimicrobials are the two main reasons for the

  11. Antimicrobial resistance of Campylobacter jejuni and Campylobacter coli from poultry in Italy.

    PubMed

    Giacomelli, Martina; Salata, Cristiano; Martini, Marco; Montesissa, Clara; Piccirillo, Alessandra

    2014-04-01

    This study was aimed at assessing the antimicrobial resistance (AMR) of Campylobacter isolates from broilers and turkeys reared in industrial farms in Northern Italy, given the public health concern represented by resistant campylobacters in food-producing animals and the paucity of data about this topic in our country. Thirty-six Campylobacter jejuni and 24 Campylobacter coli isolated from broilers and 68 C. jejuni and 32 C. coli from turkeys were tested by disk diffusion for their susceptibility to apramycin, gentamicin, streptomycin, cephalothin, cefotaxime, ceftiofur, cefuroxime, ampicillin, amoxicillin+clavulanic acid, nalidixic acid, flumequine, enrofloxacin, ciprofloxacin, erythromycin, tilmicosin, tylosin, tiamulin, clindamycin, tetracycline, sulfamethoxazole+trimethoprim, chloramphenicol. Depending on the drug, breakpoints provided by Comité de l'antibiogramme de la Société Française de Microbiologie, Clinical and Laboratory Standards Institute, and the manufacturer were followed. All broiler strains and 92% turkey strains were multidrug resistant. Very high resistance rates were detected for quinolones, tetracycline, and sulfamethoxazole+trimethoprim, ranging from 65% to 100% in broilers and from 74% to 96% in turkeys. Prevalence of resistance was observed also against ampicillin (97% in broilers, 88% in turkeys) and at least three cephalosporins (93-100% in broilers, 100% in turkeys). Conversely, no isolates showed resistance to chloramphenicol and tiamulin. Susceptibility prevailed for amoxicillin+clavulanic acid and aminoglycosides in both poultry species, and for macrolides and clindamycin among turkey strains and among C. jejuni from broilers, whereas most C. coli strains from broilers (87.5%) were resistant. Other differences between C. jejuni and C. coli were observed markedly in broiler isolates, with the overall predominance of resistance in C. coli compared to C. jejuni. This study provides updates and novel data on the AMR of broiler and

  12. Gradient HPLC of antibiotics in urine, ground water, chicken muscle, hospital wastewater, and pharmaceutical samples using C-18 and RP-amide columns.

    PubMed

    Kumar, Ashwini; Kumar Malik, Ashok; Kumar Tewary, Dhananjay; Singh, Baldev

    2008-02-01

    A simple and highly sensitive high pressure liquid chromatographic (HPLC-UV) method has been developed for the determination of ofloxacin, lomefloxacin, cinoxacin, and nalidixic acid, in mobile phase citrate buffer (0.001 M) of pH 4.5 prepared in water (X), methanol (Y), and ACN (Z) using gradient at a flow rate of 1.0 mL/min by direct UV absorbance detection at lambda = 280 nm. Separation of analytes was studied on the C-18 and RP-amide columns and best results were observed on the RP-amide column with LODs (3.3 x S/m) 0.89, 0.55, 0.67, and 1.41 ng/mL for ofloxacin, lomefloxacin, cinoxacin, and nalidixic acid, respectively, and better RSD than the C-18 column. The recovery of Fluoroquinolones (FQs) in urine, ground water, hospital wastewater, and chicken muscle using this method is more than 90%. The method was successfully applied to the analysis of ofloxacin, lomefloxacin, cinoxacin, and nalidixic acid in urine, ground water, pharmaceutical dosage forms, hospital wastewater, and chicken muscle.

  13. Comparison of auto-fluorescence and tetracycline fluorescence for guided bone surgery of medication-related osteonecrosis of the jaw: a randomized controlled feasibility study.

    PubMed

    Ristow, O; Otto, S; Geiß, C; Kehl, V; Berger, M; Troeltzsch, M; Koerdt, S; Hohlweg-Majert, B; Freudlsperger, C; Pautke, C

    2017-02-01

    Recent studies have indicated that bone shows auto-fluorescence under an appropriate fluorescence lamp. The aim of this preliminary study was to compare the success rates of the established tetracycline fluorescence-guided bone surgery with auto-fluorescence-guided bone surgery in the treatment of medication-related osteonecrosis of the jaw (MRONJ). Forty patients suffering from MRONJ were referred for surgical treatment and were divided randomly into two groups: auto-fluorescence (n=20) or tetracycline fluorescence (n=20) guided bone surgery. The primary endpoint was treatment success, defined as the absence of exposed bone at 8 weeks after surgery. Secondary outcomes assessed were mucosal integrity, signs of infection, pain, and loss of sensitivity; these were evaluated descriptively at 10 days, 8 weeks, 6 months, and 1 year after surgery. At 8 weeks postoperative, 18/20 patients (90%) in the auto-fluorescence group and 17/20 patients (85%) in the tetracycline fluorescence group showed mucosal integrity (P>0.05). At the last follow-up, 94% in the auto-fluorescence group and 89% in the tetracycline fluorescence group presented complete mucosal coverage with no exposed bone, infection, or pain (P>0.05). There was no significant difference between the two techniques for any of the secondary outcomes (P>0.05). The results of this preliminary study show that auto-fluorescence-guided bone surgery has comparable success rates to the established tetracycline fluorescence-guided bone surgery. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  14. Streptococcus agalactiae clones infecting humans were selected and fixed through the extensive use of tetracycline.

    PubMed

    Da Cunha, Violette; Davies, Mark R; Douarre, Pierre-Emmanuel; Rosinski-Chupin, Isabelle; Margarit, Immaculada; Spinali, Sebastien; Perkins, Tim; Lechat, Pierre; Dmytruk, Nicolas; Sauvage, Elisabeth; Ma, Laurence; Romi, Benedetta; Tichit, Magali; Lopez-Sanchez, Maria-José; Descorps-Declere, Stéphane; Souche, Erika; Buchrieser, Carmen; Trieu-Cuot, Patrick; Moszer, Ivan; Clermont, Dominique; Maione, Domenico; Bouchier, Christiane; McMillan, David J; Parkhill, Julian; Telford, John L; Dougan, Gordan; Walker, Mark J; Holden, Matthew T G; Poyart, Claire; Glaser, Philippe

    2014-08-04

    Streptococcus agalactiae (Group B Streptococcus, GBS) is a commensal of the digestive and genitourinary tracts of humans that emerged as the leading cause of bacterial neonatal infections in Europe and North America during the 1960s. Due to the lack of epidemiological and genomic data, the reasons for this emergence are unknown. Here we show by comparative genome analysis and phylogenetic reconstruction of 229 isolates that the rise of human GBS infections corresponds to the selection and worldwide dissemination of only a few clones. The parallel expansion of the clones is preceded by the insertion of integrative and conjugative elements conferring tetracycline resistance (TcR). Thus, we propose that the use of tetracycline from 1948 onwards led in humans to the complete replacement of a diverse GBS population by only few TcR clones particularly well adapted to their host, causing the observed emergence of GBS diseases in neonates.

  15. Sensitive determination of four tetracycline antibiotics in pig plasma by field-amplified sample stacking open-tubular capillary electrochromatography with dimethylethanolamine aminated polychloromethyl styrene nano-latex coated capillary column.

    PubMed

    Guo, Yaxiao; Meng, Lei; Zhang, Yanhao; Tang, Wei; Zhang, Wenfen; Xia, Yan; Ban, Fuguo; Wu, Ningpeng; Zhang, Shusheng

    2013-12-30

    This paper described the preparation and application of a new dimethylethanolamine aminated polychloromethyl styrene nano-latex (DMEAPL) coated capillary column (ccc-DMEAPL) in the determination of four tetracycline antibiotics (TCA) including tetracycline (TC), oxytetracycline (OTC), doxycycline (DC) and chlorotetracycline (CTC) in pig plasma. The ccc-DMEAPL column was characterized with steady EOF values of ca. 1.5-5.2×10(-5)cm(2)/Vs at pH 1.8-6.3. The optimized conditions for field-amplified sample stacking open-tubular capillary electrochromatography (FASS-OT-CEC) were as following: background electrolyte, 10mmol/L Na2HPO4+15mmol/L citric acid (pH 3.2); ccc-DMEAPL, 50μm i.d.×50cm (effective length 41.5cm), separation voltage, 18kV; column temperature, 25°C; UV detection wavelength, 270nm; water-plug injection: 30mbar×10s; sample electrokinetic injection, 10kV×20s. The four TCA were extracted with the solution of 10mmol/L Na2HPO4+15mmol/L citric acid+4g/L EDTA-2Na (pH 3.2). The FASS-OT-CEC method was validated in terms of linearity, sensitivity, selectivity, precision and accuracy. The LODs ranged from 3 to 7ng/mL, the recoveries for the four TCA were all more than 80%. The developed method was successfully applied for the determination of TCs in the actual pig plasma samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Characterization of Shigella sonnei isolates from travel-associated cases in Japan.

    PubMed

    Izumiya, Hidemasa; Tada, Yuki; Ito, Kenichiro; Morita-Ishihara, Tomoko; Ohnishi, Makoto; Terajima, Jun; Watanabe, Haruo

    2009-11-01

    Shigella sonnei infection in industrialized countries is often associated with foreign travel. A total of 195 S. sonnei isolates in Japan, isolated from cases associated with foreign travel, were analysed by biotyping and molecular typing using PFGE and multilocus variable-number tandem-repeat analysis (MLVA); their antimicrobial susceptibilities were also evaluated. The isolates were from 26 countries, most of which were Asian. Molecular typing revealed a correlation among the genotypes, biotypes and their geographical areas of origin. The isolates were classified into two biotypes, a and g. Biotype g isolates (n=178) were further divided into distinct clusters mainly on the basis of their geographical areas of origin by both PFGE and MLVA. Isolates from South Asian countries constituted one of the distinct clusters. Biotype g isolates from countries other than South Asia constituted other distinct clusters. Most of the isolates from other countries and continents, excluding the South Asian countries, were included in one major cluster by PFGE analysis. However, by MLVA, they were further divided into minor subclusters mainly on the basis of their countries of origin. MLVA was also demonstrated to be useful in molecular epidemiological analysis, even when only seven loci were applied, resulting in a high resolution with Simpson's index of diversity (D) of 0.993. A core drug-resistance pattern of streptomycin, sulfisoxazole, tetracycline and trimethoprim-sulfamethoxazole was observed in 108 isolates, irrespective of their geographical areas of origin, but the frequency of resistance to nalidixic acid was high among the South Asian and East Asian isolates. Two isolates from China and India were resistant to cefotaxime and harboured the bla(CTX-M-14) and bla(CTX-M-15) genes, respectively; these isolates were also resistant to nalidixic acid, which is a matter of concern in terms of shigellosis treatment. Use of a combination of methods was found to be effective for

  17. Photocatalytic degradation of tetracycline by Ti-MCM-41 prepared at room temperature and biotoxicity of degradation products

    NASA Astrophysics Data System (ADS)

    Zhou, Kefu; Xie, Xiao-Dan; Chang, Chang-Tang

    2017-09-01

    Ti-doped MCM-41 with different Si/Ti molar ratios was prepared at room temperature to degrade tetracycline antibiotics in aqueous solution. The Ti was doped into the skeleton structure of MCM-41. The photocatalytic activity of Ti-doped MCM-41 was investigated. The optimal catalyst had Si/Ti molar ratio of 25 and over 99% removal of oxytetracycline in 150 min, and the removal could maintain 98% after 5 reuses. Ions and soluble organic matters in natural water affected the degradation reaction when Ti-doped MCM-41 was used to treat simulated wastewater of chicken farms. The degradation products of oxytetracycline, tetracycline and chlortetracycline were detected by Escherichia coli DH5α and HPLC-MS/MS. No intermediate product with higher toxicity was detected.

  18. Novel plasmid conferring kanamycin and tetracycline resistance in turkey-derived Campylobacter jejuni strain 11601MD

    USDA-ARS?s Scientific Manuscript database

    In Campylobacter spp., resistance to the antibiotics kanamycin and tetracycline is frequently associated with plasmid-borne genes. However, relatively few plasmids of Campylobacter jejuni have been fully characterized to date. A novel plasmid (p11601MD; 44,095 bp.) harboring tet(O) was identified in...

  19. Outbreak of acute colitis on a horse farm associated with tetracycline-contaminated sweet feed.

    PubMed Central

    Keir, A A; Stämpfli, H R; Crawford, J

    1999-01-01

    Exposure of a group of horses to tetracycline-contaminated feed resulted in acute colitis and subsequent death in one horse and milder diarrhea in 3 others. The most severely affected animal demonstrated clinical and pathological findings typical of colitis X. The other herdmates responded well to administration of zinc bacitracin. PMID:10572668

  20. Occurrence and transport of tetracycline, sulfonamide, quinolone, and macrolide antibiotics in the Haihe River Basin, China.

    PubMed

    Luo, Yi; Xu, Lin; Rysz, Michal; Wang, Yuqiu; Zhang, Hao; Alvarez, Pedro J J

    2011-03-01

    The occurrence and transport of 12 antibiotics (from the tetracycline, sulfonamide, quinolone, and macrolide families) was studied in a 72-km stretch of the Haihe River, China, and in six of its tributaries. Aqueous and sediment samples were analyzed by HPLC-MS/MS. Sulfonamides were detected at the highest concentrations (24-385 ng/L) and highest frequencies (76-100%). Eight of the 12 antibiotics likely originated from veterinary applications in swine farms and fishponds, and concentrations at these sources (0.12-47 μg/L) were 1-2 orders of magnitude higher than in the effluent of local wastewater treatment plants. Sulfachloropyridazine (SCP) was detected in all swine farm and fishpond samples (maximum concentration 47 μg/L), which suggests its potential usefulness to indicate livestock source pollution in the Haihe River basin. Hydrological and chemical factors that may influence antibiotic distribution in the Haihe River were considered by multiple regression analysis. River flow rate exerted the most significant effect on the first-order attenuation coefficient (K) for sulfonamides, quinolones, and macrolides, with higher flow rates resulting in higher K, probably due to dilution. For tetracyclines, sediment total organic matter and cation exchange capacity exerted a greater impact on K than flow rate, indicating that adsorption to sediments plays an important role in attenuating tetracycline migration. Overall, the predominance of sulfonamides in the Haihe River underscores the need to consider regulating their veterinary use and improving the management and treatment of associated releases.

  1. Magnetic adsorbent constructed from the loading of amino functionalized Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalates nanoparticle and its tetracycline adsorption removal property study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ou, Jinzhao; Mei, Mingliang; Xu, Xinxin, E-mail: xuxx@mail.neu.edu.cn

    2016-06-15

    A magnetic polyoxometalates based adsorbent has been synthesized successfully through the loading of amino functionalized Fe{sub 3}O{sub 4} (NH{sub 2}-Fe{sub 3}O{sub 4}) on nanoparticle of a coordination complex modified polyoxometalates (CC/POMNP). FTIR illustrate there exist intense hydrogen bonds between NH{sub 2}-Fe{sub 3}O{sub 4} and CC/POMNP, which keep the stability of this adsorbent. At room temperature, this adsorbent exhibits ferromagnetic character with saturation magnetization of 8.19 emu g{sup −1}, which provides prerequisite for fast magnetic separation. Water treatment experiment illustrates this POM based magnetic adsorbent exhibits high adsorption capacity on tetracycline. The adsorption process can be described well with Temkin model,more » which illustrates the interaction between adsorbent and tetracycline plays the dominated role in tetracycline removal. The rapid, high efficient tetracycline adsorption ability suggests this POM based magnetic adsorbent exhibits promising prospect in medical and agriculture waste water purification. A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalates - Graphical abstract: A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalate. Display Omitted - Highlights: • A POM based magnetic adsorbent was fabricated through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on POM nanoparticle. • This adsorbent possesses excellent tetracycline adsorption property. • Saturation magnetization value of this adsorbent is 8.19 emug−1, which is enough for magnetic separation.« less

  2. Molecular identification of drug resistant mutations to tetracycline in Mycoplasma spp. isolated from patients with multiple sclerosis.

    PubMed

    Naghib, M; Kheirkhah, B; Mohebbi, R; Sadeg, L

    2017-08-15

    Bacterial infections play a significant role in causing or intensifying the attacks in MS and there are reports based on the interference of Mycoplasma with a global distribution. Mycoplasma causes autoimmune attacks by imitating the host cell membrane, which is a way of resistance to antibiotics. The purpose of this study was to evaluate the molecular identification of mutations causing resistance to tetracycline in Mycoplasma isolated from MS patients. A total number of 32 cerebrospinal fluid samples and 48 urinal fluid samples were collected from MS patients. The samples were enriched in 7 PPLO broth for one night and continuous cultivation in agar PPLO and PPLO broth for one week. DNA was extracted, and then nested PCR and Doublex PCR were used for bacteria genus identification and the presence of potential tetracycline-resistant alleles (rrs4 and rrs3), respectively.  A total number of 12 samples created colonies. However, only 5 samples (1 cerebrospinal fluid and 4 urinal samples) were detected to be Mycoplasma. The urinal samples showed the desired alleles and were tetracycline-resistant. By sequencing the PCR products, it was shown that these alleles have mutated in various points. Based on the results it seems that the resistant mutated Mycoplasma can be detected in MS patients in our population and may be considered as a risk factor for the disease.

  3. Adsorption of quinolone, tetracycline, and penicillin antibiotics from aqueous solution using activated carbons: Review.

    PubMed

    Ahmed, Muthanna J

    2017-03-01

    Antibiotics, an important type of pharmaceutical pollutant, have attracted many researchers to the study of their removal from aqueous solutions. Activated carbon (AC) has been widely used as highly effective adsorbent for antibiotics because of its large specific surface area, high porosity, and favorable pore size distribution. In this article, the adsorption performance of AC towards three major types of antibiotics such as tetracyclines, quinolones, and penicillins were reviewed. According to collected data, maximum adsorption capacities of 1340.8, 638.6, and 570.4mg/g were reported for tetracyclines, quinolones, and penicillins, respectively. The values of 1/n for Freundlich isotherm were less than unity, suggesting that the adsorption was nonlinear and favorable. Adsorption kinetics followed closely the pseudo-second-order model and analysis using the Weber-Morris model revealed that the intra-particle diffusion was not the only rate controlling step. AC adsorption demonstrated superior performance for all selected drugs, thus being efficient technology for treatment of these pollutants. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Comparative Susceptibility of Haemophilus Species to Cefaclor, Cefamandole, and Five Other Cephalosporins and Ampicillin, Chloramphenicol, and Tetracycline

    PubMed Central

    Watanakunakorn, Chatrchai; Glotzbecker, Cheryl

    1979-01-01

    The minimal inhibitory concentration of cefaclor, cephalexin, cephradine, cefamandole, cephalothin, cephapirin, cefazolin, ampicillin, chloramphenicol, and tetracycline for inhibition of 198 freshly isolated clinical strains of Haemophilus species (23 H. influenzae type b, 157 H. influenzae non-type b, 14 H. parainfluenzae, and 4 H. aphrophilus) was determined simultaneously by a slightly modified WHO-ICS agar dilution method. Nine strains were resistant to ampicillin. There was no correlation between ampicillin resistance and minimal inhibitory concentration of other antibiotics. All strains were susceptible to chloramphenicol, and all except five were susceptible to tetracycline. Cefaclor was the most active oral cephalosporin, and cefamandole was the most active parenteral cephalosporin. Among the seven cephalosporins tested, cefamandole was the most effective compound. All but two strains were inhibited by cefamandole at 2 μg or less per ml. PMID:258112

  5. Meat industry wastewater: microbiological quality and antimicrobial susceptibility of E. coli and Salmonella sp. isolates, case study in Vojvodina, Serbia.

    PubMed

    Stošić, Milena; Čučak, Dragana; Kovačević, Srđan; Perović, Marija; Radonić, Jelena; Turk Sekulić, Maja; Vojinović Miloradov, Mirjana; Radnović, Dragan

    2016-01-01

    Wastewater from meat processing industries is a fusion of compounds with a high load of organic matter, and pathogen microorganisms like Escherichia coli, and Salmonella sp. The aim of this research was to determine microbiological characteristics of the wastewater discharged from the meat processing industry in order to get a more detailed insight into meat industry wastewater pollution, and to evaluate the resistance of bacterial strains E. coli and Salmonella sp. to antibiotics. The evaluation of the antimicrobial susceptibility was performed on 37 strains of E. coli and eight strains of Salmonella sp. to nine different antibiotics. The number of faecal pollution indicators was very high in all samples. From a total of 37 strains of E. coli, a moderate degree of resistance was shown to tetracycline (37.83%); a low degree of resistance to ampicillin (21.62%), streptomycin (24.32%), trimethoprim-sulfamethoxazol (18.92%) and nalidixic acid (16.22%); and very low to: chloramphenicol (13.51%), ciprofloxacin (2.7%), gentamicin and cefotaxime (0.0%). The results for eight strains of Salmonella sp. show that all eight isolates had some degree of susceptibility to nine tested antimicrobial agents and six strains were fully susceptible to all tested antibiotics.

  6. Characterization of Salmonella spp. from wastewater used for food production in Morogoro, Tanzania.

    PubMed

    Mhongole, Ofred J; Mdegela, Robinson H; Kusiluka, Lughano J M; Forslund, Anita; Dalsgaard, Anders

    2017-03-01

    Wastewater use for crop irrigation and aquaculture is commonly practiced by communities situated close to wastewater treatment ponds. The objective of this study was to characterize Salmonella spp. and their antimicrobial susceptibility patterns among isolates from wastewater and Tilapia fish. A total of 123 Salmonella spp. isolates were isolated from 52 water and 21 fish intestinal samples. Genotyping of Salmonella spp. isolates was done by Pulsed-field Gel Electrophoresis (PFGE). Antimicrobial susceptibility testing was done by the minimal inhibitory concentration (MIC) technique. A total of 123 Salmonella spp. isolates represented 13 different serovars and 22 PFGE groups. Salmonella serovars showed resistance to 8 out of 14 antimicrobials; sulfamethaxazole (94%), streptomycin (61%), tetracycline (22%), ciprofloxacin and nalidixic acid (17%), trimethoprim (11%); gentamycin and chloramphenicol (6%). Salmonella Kentucky, S. Chandans, S. Durban and S. Kiambu showed multiple antimicrobial resistance to 7, 6 and 3 antimicrobials, respectively. This study has demonstrated that wastewater at the study sites is contaminated with Salmonella spp. which are resistant to common antimicrobials used for treatment of diseases in humans. Wastewater may, therefore, contaminate pristine surface water bodies and foodstuffs including fish and irrigated crops as well as food handlers.

  7. Salmonella in raw chicken meat from the Romanian seaside: frequency of isolation and antibiotic resistance.

    PubMed

    Tîrziu, Emil; Lazăr, Romeu; Sala, Claudia; Nichita, Ileana; Morar, Adriana; Şereş, Monica; Imre, Kálmán

    2015-05-01

    The purpose of this study was to investigate the occurrence of Salmonella in raw chicken meat samples collected at the Romanian seaside and to evaluate the antimicrobial susceptibility of the isolates. In 2012, 317 chicken meat samples from slaughterhouses (n = 289) and retail markets (n = 28) were evaluated. Overall, 13.2% (42) of the samples contained Salmonella; 12.8% (37) and 17.8% (5) from the chicken carcasses at slaughterhouses and the fresh meat from retail markets, respectively. Eight serotypes of Salmonella enterica subsp. enterica were identified: Infantis (18 isolates), Bredeney (7), Virchow (6), Djugu (4), Grampian (4), Brandenburg (1), Derby (1), and Ruzizi (1). The isolates were resistant to tetracycline (66.6% of isolates), nalidixic acid (64.3%), sulfamethoxazole (64.3%), ciprofloxacin (61.9%), streptomycin (59.5%), trimethoprim (33.3%), ampicillin (9.5%), chloramphenicol (7.1%), and gentamicin (2.4%). No resistance was found to cefotaxime and ceftazidime. Thirty (71.4%) of the 42 tested isolates had multidrug resistance patterns to at least two antimicrobials. This survey highlighted a multidrug-resistant Salmonella contamination rate in raw chicken meat in this area of Romania, which can seriously threaten human health.

  8. Vibrio cholerae O1 Ogawa Strains Carrying the ctxB7 Allele Caused a Large Cholera Outbreak during 2014 in the Tribal Areas of Odisha, India.

    PubMed

    Pal, Bibhuti Bhusan; Khuntia, Hemant Kumar; Nayak, Smruti Ranjan; Mohanty, Anima; Biswal, Bhagyalaxmi

    2017-09-25

    The large outbreak of cholera reported during July to September 2014 in the Narla block of Kalahandi district, India, was investigated to determine the causative organism. Rectal swabs collected from patients with diarrhea and environmental water samples were cultured following standard techniques. The causative organism was identified as Vibrio cholerae O1 Ogawa biotype El Tor, and analysis by double mismatch mutation assay PCR confirmed that all strains were the ctxB7 variant of Haitian V. cholerae O1. The environmental water samples were negative for V. cholerae. The V. cholerae O1 strains were sensitive to tetracycline, ciprofloxacin, norfloxacin, ofloxacin, doxycycline, and azithromycin, but were resistant to erythromycin, gentamicin, chloramphenicol, furazolidone, neomycin, cotrimoxazole, nalidixic acid, and ampicillin. In the 2014 cholera outbreak, the early reporting of the pathogen enabled the government authorities to implement adequate control measures in time to curtail the spread of the disease. That was the second large cholera outbreak due to Haitian variants of V. cholerae O1 after the 2010 Haiti cholera outbreak reported from Odisha, India, and other locations globally. Active surveillance is required to track the spread of this strain in the Odisha region.

  9. Detection of Salmonella spp. in Retail Raw Food Samples from Vietnam and Characterization of Their Antibiotic Resistance▿

    PubMed Central

    Van, Thi Thu Hao; Moutafis, George; Istivan, Taghrid; Tran, Linh Thuoc; Coloe, Peter J.

    2007-01-01

    A study was conducted to examine the levels of Salmonella spp. contamination in raw food samples, including chicken, beef, pork, and shellfish, from Vietnam and to determine their antibiotic resistance characteristics. A total of 180 samples were collected and examined for the presence of Salmonella spp., yielding 91 Salmonella isolates. Sixty-one percent of meat and 18% of shellfish samples were contaminated with Salmonella spp. Susceptibility of all isolates to a variety of antimicrobial agents was tested, and resistance to tetracycline, ampicillin/amoxicillin, nalidixic acid, sulfafurazole, and streptomycin was found in 40.7%, 22.0%, 18.7%, 16.5%, and 14.3% of the isolates, respectively. Resistance to enrofloxacin, trimethoprim, chloramphenicol, kanamycin, and gentamicin was also detected (8.8 to 2.2%). About half (50.5%) of the isolates were resistant to at least one antibiotic, and multiresistant Salmonella isolates, resistant to at least three different classes of antibiotics, were isolated from all food types. One isolate from chicken (serovar Albany) contained a variant of the Salmonella genomic island 1 antibiotic resistance gene cluster. The results show that antibiotic resistance in Salmonella spp. in raw food samples from Vietnam is significant. PMID:17766455

  10. Antimicrobial Resistance and Molecular Typing of Salmonella Stanley Isolated from Humans, Foods, and Environment.

    PubMed

    Yang, Xiaowei; Kuang, Dai; Meng, Jianghong; Pan, Haijian; Shen, Junqing; Zhang, Jing; Shi, Weimin; Chen, Qi; Shi, Xianming; Xu, Xuebin; Zhang, Jianmin

    2015-12-01

    Salmonella enterica serovar Stanley is an important serovar that has been increasingly identified in human salmonellosis. The present study aimed to investigate the antimicrobial resistance and molecular typing of 88 Salmonella Stanley strains isolated from humans (diarrhea patients, n = 64; and healthy carrier, n = 1), foods (aquatic products, n = 16; vegetable, n = 1; and pork, n = 1), and environment (waste water, n = 2; and river water, n = 3) in Shanghai, China from 2006 to 2012. Nearly half of the strains were resistant to sulfafurazole (43/88, 48.9%), and many were resistant to streptomycin (35/88, 39.8%), tetracycline (22/88, 25%), and nalidixic acid (19/88, 21.6%). Approximately a quarter of the strains (24/88, 27.3%) were resistant to more than three antimicrobials, and five had ACSSuT resistance type. Six clusters (A-F) were identified by pulsed-field gel electrophoresis (PFGE) with 80% similarity. Interestingly, strains in the same cluster identified by PFGE possessed similar antibiotic resistance patterns. PFGE typing also indicated that aquatic products might serve as a transmission reservoir for Salmonella Stanley infections in humans.

  11. Improved agar diffusion method for detecting residual antimicrobial agents.

    PubMed

    Tsai, C E; Kondo, F

    2001-03-01

    The improved agar diffusion method for determination of residual antimicrobial agents was investigated, and the sensitivities of various combinations of test organisms and assay media were determined using 7 organisms, 5 media, and 31 antimicrobial agents. Bacillus stearothermophilus and synthetic assay medium (SAM) showed the greatest sensitivity for screening penicillins (penicillin G and ampicillin). The combination of Bacillus subtilis and minimum medium (MM) was the most sensitive for tetracyclines (oxytetracycline and chlortetracycline), B. stearothermophilus and SAM or Micrococcus luteus and Mueller-Hinton agar (MHA) for detecting tylosin and erythromycin, B. subtilis and MHA for aminoglycosides (streptomycin, kanamycin, gentamicin, and dihydrostreptomycin), B. stearothermophilus and SAM for polyethers (salinomycin and lasalocid), and B. subtilis and MM or Clostridium perfringens and GAM for polypeptides (thiopeptin, enramycin, virginiamycin, and bacitracin). However, gram-negative bacterium Escherichia coli ATCC 27166 and MM were better for screening for colistin and polymixin-B. For detecting the synthetic drugs tested, the best combination was B. subtilis and MM for sulfonamides, E. coli 27166 and MM for quinolones (oxolinic acid and nalidixic acid), B. subtilis and MM for furans (furazolidone), and the bioluminescent bacterium Photobacterium phosphoreum and luminescence assay medium for chloramphenicol and oxolinic acid. The results showed that the use of four assay plates, B. stearothermophilus and SAM, B. subtilis and MM, M. luteus and MHA, and E. coli 27166 and MM, was superior to the currently available techniques for screening for residual antimicrobial agents in edible animal tissues.

  12. Spectrofluorimetric assessment of chlorzoxazone and ibuprofen in pharmaceutical formulations by using Eu-tetracycline HCl optical sensor doped in sol-gel matrix.

    PubMed

    Attia, M S; Ramsis, M N; Khalil, L H; Hashem, S G

    2012-03-01

    A novel, simple, sensitive and selective spectrofluorimetric method was developed for the determination of trace amounts of chlorzoxazone and Ibuprofen in pharmaceutical tablets using optical sensor Eu-Tetracycline HCl doped in sol-gel matrix. The chlorzoxazone or Ibuprofen can remarkably enhance the luminescence intensity of Eu-Tetracycline HCl complex doped in a sol-gel matrix in dimethylformamide (DMF) at pH 9.7 and 6.3, respectively, λ(ex) = 400 nm. The enhancing of luminescence intensity peak of Eu-Tetracycline HCl complex at 617 nm is proportional to the concentration of chlorzoxazone or Ibuprofen a result that suggested profitable application as a simple optical sensor for chlorzoxazone or Ibuprofen assessment. The dynamic ranges found for the determination of chlorzoxazone and Ibuprofen concentration are 5 × 10(-9)-1 × 10(-4) and 1 × 10(-8)-7 × 10(-5) mol L(-1), and the limit of detection (LOD) and quantitation limit of detection (LOQ) are 3.1 × 10(-10), 9.6 × 10(-10) and 5.6 × 10(-10), 1.7 × 10(-9) mol L(-1), respectively.

  13. Genotypic relatedness and antimicrobial resistance of Salmonella Heidelberg isolated from chickens and turkeys in the midwestern United States.

    PubMed

    Nisar, Muhammad; Kassem, Issmat I; Rajashekara, Gireesh; Goyal, Sagar M; Lauer, Dale; Voss, Shauna; Nagaraja, Kakambi V

    2017-05-01

    Salmonella is one of the most common causes of foodborne illnesses in humans in the United States, and domestic poultry is considered an important source of this pathogen. Salmonella enterica subsp. enterica serovar Heidelberg is the fourth most commonly reported Salmonella from retail meats and food animals in the United States. We assessed the genotypes and antimicrobial resistance phenotypes of Salmonella Heidelberg isolated from various chicken and turkey hatcheries and breeder farms in the Midwest. The genotypes of 33 S. Heidelberg isolates from chickens ( n = 19) and turkeys ( n = 14) were compared using pulsed-field gel electrophoresis analysis. Cluster analysis of the fingerprints showed that the majority of the chicken isolates grouped together with 87% similarity; those from turkeys clustered with 88% similarity. Similarity between chicken and turkey isolates was also high (86%). Isolates from turkeys were generally more genetically diverse than those from chickens. Antimicrobial susceptibility analysis detected resistance to sulfisoxazole (36% of the isolates), streptomycin (33%), gentamicin (27%), tetracycline (24%), ampicillin and amoxicillin-clavulanic acid (15%), cefoxitin (12%), ceftriaxone and ceftiofur (12%), and chloramphenicol (9%). None of the isolates was resistant to azithromycin, ciprofloxacin, or nalidixic acid. Although the number of the isolates was limited in our study, we conclude that S. Heidelberg isolates from the same host generally clustered together and that a considerable number of the isolates were resistant to a number of antimicrobial agents.

  14. [Effects of long-term application of pig manure containing residual tetracycline on the formation of drug-resistant bacteria and resistance genes].

    PubMed

    Zhang, Jun; Yang, Xiao-Hong; Ge, Feng; Wang, Na; Jiao, Shao-Jun; Jiao, Shao-Jun

    2014-06-01

    The effect of residual veterinary tetracycline on the formation of drug-resistant bacteria and corresponding resistance genes was investigated. During the research, the soil with long-term application of pig manure containing residual tetracycline was collected in autumn and summer respectively in the farmland around a certain pig farm in Shuyang City, Huang Huai area, north of Jiangsu province. At the same time, soils without application of pig manure in the farmland of this area were collected as the reference sample. Composition of drug-resistant bacteria in all soil samples was analyzed and three common tetracycline-resistance genes (tetA, tetC, tetE) were studied by PCR as well. During the research, 59 drug-resistant bacteria belonging to 13 bacterial genus respectively were separated from the soil sample collected in autumn while 35 drug- resistant bacteria belonging to 10 bacterial genus respectively were separated from the soil sample collected in summer and as for the reference sample, 3 drug-resistant bacteria belonging to 1 bacterial genus (Streptomyces) were separated with pathogenic bacteria up to 38.14% of total drug-resistant bacteria. PCR result showed that resistance genes were detected in all drug-resistant bacteria and tetC accounted for the most. At the same time, the residual tetracycline in the soil which was in a range of 41.1-61.9 microg x kg(-1) correlated with the amount of resistance genes (4.63 x 10(5)-37.42 x 10(5) copies x g(-1)). Besides, the climate was found accelerating the formation of drug-resistant bacteria and resistance genes.

  15. Occurrence and antimicrobial susceptibility of thermophilic Campylobacter species isolated from healthy children attending municipal care centers in Southern Ecuador

    PubMed Central

    Toledo, Zorayda; Simaluiza, Rosa Janneth; Astudillo, Xavier; Fernández, Heriberto

    2017-01-01

    ABSTRACT The prevalence and antimicrobial susceptibility of Campylobacter jejuni and C. coli strains in healthy, well-nourished children of middle socioeconomic level from Southern Ecuador were determined. Among the 127 children studied, 17 (13.4%) harbored Campylobacter sp. corresponding to C. jejuni (7.1%) and C. coli (6.3%) with a higher concentration of C. jejuni among boys (8.6%) and C. coli (8.8%) among girls. C. jejuni showed high resistance to nalidixic acid and ciprofloxacin (77.8%), but susceptibility to all other antimicrobials tested. C. coli strains showed resistance to more antibiotics than C. jejuni strains including resistance to nalidixic acid (75%), ciprofloxacin (75%), erythromycin (12.5%) and ampicillin (28.6), but susceptible to gentamicin and amoxicillin/clavulanic acid. PMID:29267585

  16. Occurrence and antimicrobial susceptibility of thermophilic Campylobacter species isolated from healthy children attending municipal care centers in Southern Ecuador.

    PubMed

    Toledo, Zorayda; Simaluiza, Rosa Janneth; Astudillo, Xavier; Fernández, Heriberto

    2017-12-21

    The prevalence and antimicrobial susceptibility of Campylobacter jejuni and C. coli strains in healthy, well-nourished children of middle socioeconomic level from Southern Ecuador were determined. Among the 127 children studied, 17 (13.4%) harbored Campylobacter sp. corresponding to C. jejuni (7.1%) and C. coli (6.3%) with a higher concentration of C. jejuni among boys (8.6%) and C. coli (8.8%) among girls. C. jejuni showed high resistance to nalidixic acid and ciprofloxacin (77.8%), but susceptibility to all other antimicrobials tested. C. coli strains showed resistance to more antibiotics than C. jejuni strains including resistance to nalidixic acid (75%), ciprofloxacin (75%), erythromycin (12.5%) and ampicillin (28.6), but susceptible to gentamicin and amoxicillin/clavulanic acid.

  17. Folliculitis induced by EGFR inhibitors, preventive and curative efficacy of tetracyclines in the management and incidence rates according to the type of EGFR inhibitor administered: a systematic literature review.

    PubMed

    Bachet, Jean-Baptiste; Peuvrel, Lucie; Bachmeyer, Claude; Reguiai, Ziad; Gourraud, Pierre A; Bouché, Olivier; Ychou, Marc; Bensadoun, Rene J; Dreno, Brigitte; André, Thierry

    2012-01-01

    Folliculitis is the most common side effect of epidermal growth factor receptor (EGFR) inhibitors (EGFRIs). It is often apparent, altering patients' quality of life and possibly impacting compliance. Variations in terms of the treatment-related incidence and intensity have not been fully elucidated. Tetracyclines have been recommended for the prophylaxis and treatment of folliculitis but their efficacy is yet to be established. We carried out two systematic literature reviews. The first assessed the preventive and curative efficacy of tetracyclines. The second assessed the incidence of grade 3-4 folliculitis in the main clinical studies published. In four randomized studies, preventive tetracycline treatment was associated with a significantly lower incidence of grade 2-3 folliculitis and a better quality of life in three of the four studies. In curative terms, tetracycline efficacy was not evaluated in any randomized study, but an improvement in grade ≥2 folliculitis was reported in case series. The frequency and severity of folliculitis seem to be greater with the antibodies than with the tyrosine kinase inhibitors. Analysis restricted to lung cancer studies showed a statistically greater incidence in terms of grade 3-4 folliculitis with cetuximab (9%) and erlotinib (8%) than with gefitinib (2%) (p < .0001). Unless contraindicated, a tetracycline should be routinely prescribed prophylactically for patients treated with an EGFRI (level of evidence, B2). In curative therapy, the level of evidence for tetracycline efficacy is low (level of evidence, D). The incidence of grade 3-4 folliculitis induced by EGFRIs appears to be lower with gefitinib.

  18. Prevalence of tetracycline resistance genes among multi-drug resistant bacteria from selected water distribution systems in southwestern Nigeria.

    PubMed

    Adesoji, Ayodele T; Ogunjobi, Adeniyi A; Olatoye, Isaac O; Call, Douglas R; Douglas, Douglas R

    2015-06-25

    Antibiotic resistance genes [ARGs] in aquatic systems have drawn increasing attention they could be transferred horizontally to pathogenic bacteria. Water treatment plants (WTPs) are intended to provide quality and widely available water to the local populace they serve. However, WTPs in developing countries may not be dependable for clean water and they could serve as points of dissemination for antibiotic resistant bacteria. Only a few studies have investigated the occurrence of ARGs among these bacteria including tetracycline resistance genes in water distribution systems in Nigeria. Multi-drug resistant (MDR) bacteria, including resistance to tetracycline, were isolated from treated and untreated water distribution systems in southwest Nigeria. MDR bacteria were resistant to >3 classes of antibiotics based on break-point assays. Isolates were characterized using partial 16S rDNA sequencing and PCR assays for six tetracycline-resistance genes. Plasmid conjugation was evaluated using E. coli strain DH5α as the recipient strain. Out of the 105 bacteria, 85 (81 %) and 20 (19 %) were Gram- negative or Gram- positive, respectively. Twenty-nine isolates carried at least one of the targeted tetracycline resistance genes including strains of Aeromonas, Alcaligenes, Bacillus, Klebsiella, Leucobacter, Morganella, Proteus and a sequence matching a previously uncultured bacteria. Tet(A) was the most prevalent (16/29) followed by tet(E) (4/29) and tet30 (2/29). Tet(O) was not detected in any of the isolates. Tet(A) was mostly found with Alcaligenes strains (9/10) and a combination of more than one resistance gene was observed only amongst Alcaligenes strains [tet(A) + tet30 (2/10), tet(A) + tet(E) (3/10), tet(E) + tet(M) (1/10), tet(E) + tet30 (1/10)]. Tet(A) was transferred by conjugation for five Alcaligenes and two E. coli isolates. This study found a high prevalence of plasmid-encoded tet(A) among Alcaligenes isolates, raising the possibility that this

  19. Tetracycline impregnation affects degradation of porcine collagen matrix in healthy and diabetic rats.

    PubMed

    Tal, Haim; Weinreb, Miron; Shely, Asaf; Nemcovsky, Carlos E; Moses, Ofer

    2016-07-01

    The present study evaluated the degradation of collagen matrix (CM) immersed in tetracycline (TTC) or phosphate-buffered saline (PBS) in diabetic and normoglycemic rats. Diabetes was induced in 15 rats by systemic streptozotocin (STZ) (experimental); 15 healthy rats served as controls. One day before implantation 60 CM disks, 5 mm in diameter, were labeled with biotin: 30 were immersed in tetracycline (TTC) and 30 in PBS. One disk of each type was implanted subdermally in each rat. Animals were euthanized after 3 weeks, and tissue specimens containing the disks were prepared for histologic analysis. Horseradish peroxidase (HRP)-conjugated streptavidin was used to detect the remaining biotinylated collagen. Residual collagen area within the CM disks was analyzed and compared to baseline. Diabetes significantly increased the CM degradation. Immersion of the CM disks in a 50-mg/mL TTC solution before implantation decreased its degradation both in diabetic and normoglycemic rats. Diabetes significantly increases collagen matrix degradation; immersion of collagen matrix in TTC before implantation decreases its degradation in both diabetic and normoglycemic conditions. Immersion of medical collagen devices in TTC may be an effective means to decrease their resorption rate and increase their effectiveness, especially in situations with increased degradation such as diabetes.

  20. [Salmonella of Indian origin: pseudo-susceptibility to fluoroquinolones].

    PubMed

    Denes, E; Gondran, G; Bezanahary, H; Genet, C; Rogez, J P; Weinbreck, P; Martin, C

    2005-04-01

    We report the case of a patient presenting with typhoid fever after returning from a stay in India. This infection was not cured with a course of ciprofloxacin, due to a reduced susceptibility of the bacteria to the drug. This decreased susceptibility to fluoroquinolones was not detected by the antibiogram, but the MIC for nalidixic acid was greater than 32 mg/l. This case suggests using a third generation cephalosporin instead of a quinolone, for people coming from a high-risk zone. It also suggests that the MIC for nalidixic acid and for norfloxacin can be used as the first clue for a reduced susceptibility to fluoroquinolones.

  1. Stability of Doxycycline in Feed and Water and Minimal Effective Doses in Tetracycline-Inducible Systems

    PubMed Central

    Redelsperger, Irka M; Taldone, Tony; Riedel, Elyn R; Lepherd, Michelle L; Lipman, Neil S; Wolf, Felix R

    2016-01-01

    Despite the extensive use of doxycycline in tetracycline-inducible rodent models, little is known regarding its stability in feed or water or the most effective route or dose. We assessed the concentrations of doxycycline in reverse-osmosis–purified (RO; pH 6.0) and acidified RO (pH 2.6) water in untinted or green-tinted bottles. Doxycycline remained stable in all groups for 7 d and in acidified water in untinted bottles for 14 d. Fungal growth occurred in nonacidified water in tinted and untinted bottles by 12 and 14 d, respectively, and in tinted bottles containing acidified water on day 14, but not in untinted bottles with acidified water. Doxycycline concentrations were also assessed before and at various points after the pelleting of feed from 2 vendors. Each batch was divided for storage at 4 °C, at room temperature, or within ventilated mouse isolator cages and then sampled monthly for 6 mo. Drying caused the greatest decline in doxycycline concentration, whereas γ-irradiation plus shipping and storage condition had minimal effect. Two mouse lines with tetracycline-inducible promoters received 25, 150, or 467 µg/mL or 2 mg/mL doxycycline in water and 200 or 625 ppm in feed before analysis of GFP expression. GFP was expressed in Rosa-rtTA2 mice at 150 µg/mL, whereas Cags-rtTA3 mice required 25 µg/mL. These studies indicate that 1) doxycycline-compounded feed can be handled in the same manner as standard rodent feed, 2) tinted water bottles are not necessary for maintaining drug concentrations, and 3) concentrations lower than those used typically may be effective in lines with tetracycline-inducible promoters. PMID:27423155

  2. Antibiotic resistance pattern among the Salmonella isolated from human, animal and meat in India.

    PubMed

    Singh, Shweta; Agarwal, Rajesh Kumar; Tiwari, Suresh C; Singh, Himanshu

    2012-03-01

    The present study was conducted to study the antibiotic resistance pattern among nontyphoidal Salmonella isolated from human, animal and meat. A total of 37 Salmonella strains isolated from clinical cases (human and animal) and meat during 2008-2009 belonging to 12 serovars were screened for their antimicrobial resistance pattern using 25 antimicrobial agents falling under 12 different antibiotic classes. All the Salmonella isolates tested showed multiple drug resistance varying from 5.40% to 100% with 16 of the 25 antibiotics tested. None of the isolates were sensitive to erythromycin and metronidazole. Resistance was also observed against clindamycin (94.59%), ampicillin (86.49%), co-trimoxazole (48.65%), colistin (45.94%), nalidixic acid (35.10%), amoxyclave (18.90%), cephalexin, meropenem, tobramycin, nitrofurantoin, tetracycline, amoxicillin (8.10% each), sparfloxacin and streptomycin (5.40% each). Isolates from clinical cases of animals were resistant to as many as 16 antibiotics, whereas isolates from human clinical cases and meat were resistant to 9 and 14 antibiotics, respectively. Overall, 19 resistotypes were recorded. Analysis of multiple antibiotic resistance index (MARI) indicated that clinical isolates from animals had higher MARI (0.25) as compared to isolates from food (0.22) and human (0.21). Among the different serotypes studied for antibiogram, Paratyhi B isolates, showed resistance to three to 13 antibiotics, whereas Typhimurium strains were resistant to four to seven antibiotics. Widespread multidrug resistance among the isolates from human, animal and meat was observed. Some of the uncommon serotypes exhibited higher resistance rate. Considerable changes in the resistance pattern were also noted. An interesting finding was the reemergence of sensitivity to some of the old antibiotics (chloromphenicol, tetracycline).

  3. Folliculitis Induced by EGFR Inhibitors, Preventive and Curative Efficacy of Tetracyclines in the Management and Incidence Rates According to the Type of EGFR Inhibitor Administered: A Systematic Literature Review

    PubMed Central

    Bachet, Jean-Baptiste; Peuvrel, Lucie; Bachmeyer, Claude; Reguiai, Ziad; Gourraud, Pierre A.; Bouché, Olivier; Ychou, Marc; Bensadoun, Rene J.; Dreno, Brigitte

    2012-01-01

    Introduction. Folliculitis is the most common side effect of epidermal growth factor receptor (EGFR) inhibitors (EGFRIs). It is often apparent, altering patients' quality of life and possibly impacting compliance. Variations in terms of the treatment-related incidence and intensity have not been fully elucidated. Tetracyclines have been recommended for the prophylaxis and treatment of folliculitis but their efficacy is yet to be established. Materials and Methods. We carried out two systematic literature reviews. The first assessed the preventive and curative efficacy of tetracyclines. The second assessed the incidence of grade 3–4 folliculitis in the main clinical studies published. Results. In four randomized studies, preventive tetracycline treatment was associated with a significantly lower incidence of grade 2–3 folliculitis and a better quality of life in three of the four studies. In curative terms, tetracycline efficacy was not evaluated in any randomized study, but an improvement in grade ≥2 folliculitis was reported in case series. The frequency and severity of folliculitis seem to be greater with the antibodies than with the tyrosine kinase inhibitors. Analysis restricted to lung cancer studies showed a statistically greater incidence in terms of grade 3–4 folliculitis with cetuximab (9%) and erlotinib (8%) than with gefitinib (2%) (p < .0001). Conclusion. Unless contraindicated, a tetracycline should be routinely prescribed prophylactically for patients treated with an EGFRI (level of evidence, B2). In curative therapy, the level of evidence for tetracycline efficacy is low (level of evidence, D). The incidence of grade 3–4 folliculitis induced by EGFRIs appears to be lower with gefitinib. PMID:22426526

  4. Trace analysis of trimethoprim and sulfonamide, macrolide, quinolone, and tetracycline antibiotics in chlorinated drinking water using liquid chromatography electrospray tandem mass spectrometry

    USGS Publications Warehouse

    Ye, Z.; Weinberg, H.S.; Meyer, M.T.

    2007-01-01

    A multirun analytical method has been developed and validated for trace determination of 24 antibiotics including 7 sulfonamides, 3 macrolides, 7 quinolones, 6 tetracyclines, and trimethoprim in chlorine-disinfected drinking water using a single solid-phase extraction method coupled to liquid chromatography with positive electrospray tandem mass spectrometry detection. The analytes were extracted by a hydrophilic-lipophilic balanced resin and eluted with acidified methanol (0.1% formic acid), resulting in analyte recoveries generally above 90%. The limits of quantitation were mostly below 10 ng/L in drinking water. Since the concentrated sample matrix typically caused ion suppression during electrospray ionization, the method of standard addition was used for quantitation. Chlorine residuals in drinking water can react with some antibiotics, but ascorbic acid was found to be an effective chlorine quenching agent without affecting the analysis and stability of the antibiotics in water. A preliminary occurrence study using this method revealed the presence of some antibiotics in drinking waters, including sulfamethoxazole (3.0-3.4 ng/L), macrolides (1.4-4.9 ng/L), and quinolones (1.2-4.0 ng/L). ?? 2007 American Chemical Society.

  5. A simple surface-enhanced Raman spectroscopic method for on-site screening of tetracycline residue in whole milk

    USDA-ARS?s Scientific Manuscript database

    Therapeutic and sub-therapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain t...

  6. Novel silver nanoparticle-enhanced fluorometric determination of trace tetracyclines in aqueous solutions.

    PubMed

    Wang, Ping; Wu, Tun-Hua; Zhang, Yong

    2016-01-01

    Metal-enhanced fluorescence (MEF) has exhibited promise for applications in fluorometric assays. The effects of silver nanoparticles (AgNP) on the fluorescence behaviours of tetracycline hydrochloride (TCH) and chlortetracycline hydrochloride (CTC) in aqueous solutions were investigated. The experimental results demonstrated that the fluorescence intensities of each tetracycline in water solutions were greatly enhanced by AgNP through the MEF effect. In addition, a novel silver nanoparticle-enhanced fluorometric method was established for the direct determination of TCH and CTC in aqueous solutions. Under optimum experimental conditions, the linear dynamic ranges for the determination of TCH and CTC in aqueous solutions varied from 0.10 to 6.0 mg L(-1) and 0.050 to 3.0 mg L(-1) with detection limits of 0.63 µg L(-1) and 0.19 µg L(-1), respectively, and with the relative standard deviation of less than 1.9% (n=9). The experimental recovery results for the determination of TCH and CTC in aqueous solutions ranged from 93-106% and 95-104%, respectively. Compared with the established method without the addition of AgNP, the limits of quantitation of the silver nanoparticle-enhanced fluorometric method were approximately 5-fold lower for TCH and 3-fold lower for CTC. Moreover, the newly established silver nanoparticle-enhanced fluorometric method was successfully applied to the direct determination of TCH and CTC in pharmaceutical preparations. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. [Acne therapy with topical benzoyl peroxide, antibiotics and azelaic acid].

    PubMed

    Worret, Wolf-Ingo; Fluhr, Joachim W

    2006-04-01

    Benzoyl peroxide (BPO) was introduced in the treatment of acne in 1934. Despite the fact that only few randomized trials have been published, BPO is considered the standard in topical acne treatment. Anaerobic bacteria are reduced by oxidative mechanisms and the induction of resistant strains is reduced. Topical formulations are available at concentrations of 2.5, 5, 10 and 20 %. The effect is dose-dependent, but the irritation increases with higher concentrations. Usually 5 % BPO is sufficient to control acne grade I-II. Due to its strong oxidative potential, patients should be advised that BPO may bleach colored and dark clothing, bedding and even hair. BPO is safe for use in pregnant and lactating females because it is degraded to benzoic acid. It is a cost-effective treatment for acne grade I-II. Patients with papulopustular acne grade I-II, particularly with marked inflammation, show satisfactory improvement with topical antibiotic treatment. The following compounds are available and effective: erythromycin, clindamycin and tetracycline (the latter being less frequently used). A review in 1990 suggested that topical tetracycline was ineffective in the treatment of acne. Along with eliminating Propionibacterium acnes, the main mechanism of topical antibiotics is their antiinflammatory effect. All three penetrate the epidermal barrier well and are similarly efficacious. Randomized trials have shown that in concentrations of 2-4 %, their effects are comparable to oral tetracycline and minocycline. Combination therapy with retinoids or benzoyl peroxide (BPO) increases efficacy. Retinoids increase penetration and reduce comedones, while topical antibiotics primarily address inflammation. One side effect of topical antibacterial treatment is an increase in drug-resistant resident skin flora with gram-negative microorganisms prevailing, which can lead to gram-negative folliculitis. All three antibiotics fluoresce under black light which may produce interesting

  8. Occurrence of plasmid-mediated quinolone resistance determinants and rmtB gene in Salmonella enterica serovar enteritidis and Typhimurium isolated from food-animal products in Tunisia.

    PubMed

    Al-Gallas, Nazek; Abbassi, Mohamed Salah; Gharbi, Becher; Manai, Molka; Ben Fayala, Mohamed N; Bichihi, Raghda; Al-Gallas, Amna; Ben Aissa, Ridha

    2013-09-01

    Four hundred and thirty Salmonella isolates, recovered from various food-animal products, were tested for nalidixic acid resistance, plasmid-mediated quinolone resistance, and genetic relationship. One hundred fifteen isolates (113 Salmonella serovar Enteritidis and two Salmonella serovar Typhimurium isolates) of 430 (26.7%) Salmonella isolates exhibited nalidixic acid resistance. Polymerase chain reaction screening for qnrA, qnrB, qnrS, qepA (encoding fluoroquinolones resistance) and rmtB (encoding aminoglycosides resistance) showed that 5 (1.16%) isolates were positive for qnr- and qepA-type genes, and the aac(6')-Ib-cr gene was observed in two (1.7%) Enteritidis isolates concomitantly with qnrA or qnrB. The co-occurrence of qepA and rmtB in one Typhimurium isolate is noteworthy. Pulsed-field gel electrophoresis revealed a high genetic homogeneity of nalidixic-resistant isolates and the persistence of clonal clusters over 4 years in different regions in Tunisia and from various food-animal products. To the best of our knowledge, this is the first report of co-occurrence of qepA and rmtB in a Salmonella strain.

  9. Nucleotide sequences of the tet(M) genes from the American and Dutch type tetracycline resistance plasmids of Neisseria gonorrhoeae.

    PubMed

    Gascoyne-Binzi, D M; Heritage, J; Hawkey, P M

    1993-11-01

    High-level tetracycline-resistant Neisseria gonorrhoeae (TRNG) has been associated with the presence of a plasmid approximately 25.2 MDa in size which carries a Tet M tetracycline resistance determinant. Two different plasmid types, American and Dutch, have previously been described, based on the restriction endonuclease digestion pattern. In this study, the tet(M) genes from the two plasmid types have been amplified by the polymerase chain reaction (PCR) and then sequenced. The gene sequences from the two plasmids shared 96.8% identity, and showed similarities with different segments of the tet(M) gene sequences from Tn1545, Tn916 and Ureaplasma urealyticum. The data suggest that it is highly likely that the Tet M determinant found in the American type plasmid has a different origin from that present in the Dutch plasmid.

  10. Tetracycline-inducible protein expression in pancreatic cancer cells: Effects of CapG overexpression

    PubMed Central

    Tonack, Sarah; Patel, Sabina; Jalali, Mehdi; Nedjadi, Taoufik; Jenkins, Rosalind E; Goldring, Christopher; Neoptolemos, John; Costello, Eithne

    2011-01-01

    AIM: To establish stable tetracycline-inducible pancreatic cancer cell lines. METHODS: Suit-2, MiaPaca-2, and Panc-1 cells were transfected with a second generation reverse tetracycline-controlled transactivator protein (rtTA2S-M2), under the control of either a cytomegalovirus (CMV) or a chicken β-actin promoter, and the resulting clones were characterised. RESULTS: Use of the chicken (β-actin) promoter proved superior for both the production and maintenance of doxycycline-inducible cell lines. The system proved versatile, enabling transient inducible expression of a variety of genes, including GST-P, CYP2E1, S100A6, and the actin capping protein, CapG. To determine the physiological utility of this system in pancreatic cancer cells, stable inducible CapG expressors were established. Overexpressed CapG was localised to the cytoplasm and the nuclear membrane, but was not observed in the nucleus. High CapG levels were associated with enhanced motility, but not with changes to the cell cycle, or cellular proliferation. In CapG-overexpressing cells, the levels and phosphorylation status of other actin-moduating proteins (Cofilin and Ezrin/Radixin) were not altered. However, preliminary analyses suggest that the levels of other cellular proteins, such as ornithine aminotransferase and enolase, are altered upon CapG induction. CONCLUSION: We have generated pancreatic-cancer derived cell lines in which gene expression is fully controllable. PMID:21528072

  11. Cow excrements enhance the occurrence of tetracycline resistance genes in soil regardless of their oxytetracycline content.

    PubMed

    Kyselková, Martina; Jirout, Jiří; Chroňáková, Alica; Vrchotová, Naděžda; Bradley, Robert; Schmitt, Heike; Elhottová, Dana

    2013-11-01

    Fertilizing soils with animal excrements from farms with common antibiotic use represents a risk of disseminating antibiotic resistance genes into the environment. In the case of tetracycline antibiotics, it is not clear, however, whether the presence of antibiotic residues further enhances the gene occurrence in manured soils. We established a microcosm experiment in which 3 farm soils that had no recent history of fertilization with animal excrements were amended on a weekly basis (9 times) with excrements from either an oxytetracycline-treated or an untreated cow. Throughout the study, the concentration of oxytetracycline in excrements from the treated cow was above 500 μg g(-1)dw, whereas no oxytetracycline was detected in excrements from the healthy cow. Both excrements contained tetracycline resistance (TC-r) genes tet(L), tet(M), tet(V), tet(Z), tet(Q) and tet(W). The excrements from the treated cow also contained the tet(B) gene, and a higher abundance of tet(Z), tet(Q) and tet(W). Three weeks after the last excrement addition, the individual TC-r genes differed in their persistence in soil: tet(Q) and tet(B) were not detectable while tet(L), tet(M), tet(Z) and tet(W) were found in all 3 soils. There were, however, no significant differences in the total number, nor in the abundance, of TC-r genes between soil samples amended with each excrement type. The oxytetracycline-rich and the oxytetracycline-free excrement therefore contributed equally to the increase of tetracycline resistome in soil. Our results indicate that other mechanisms than OTC-selection pressure may be involved in the maintenance of TC-r genes in manured soils. Copyright © 2013. Published by Elsevier Ltd.

  12. Degradation of Tetracyclines in Pig Manure by Composting with Rice Straw

    PubMed Central

    Chai, Rushan; Huang, Lidong; Li, Lingling; Gielen, Gerty; Wang, Hailong; Zhang, Yongsong

    2016-01-01

    A holistic approach was followed for utilizing tetracyclines (TCs)-contaminated pig manure, by composting this with rice straw in a greenhouse for CO2 fertilization and composted residue application. After composting, the composted residues can be applied to cropland as a supplemental source of synthetic fertilizers. The objective of this study was to determine the effect of pig manure-rice straw composting on the degradation of TCs in pig manure. The results showed that greenhouse composting significantly accelerated the degradation of TCs. Contents (150 mg·kg−1) of oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) in the composting feedstock could be completely removed within 42 days for OTC and TC, and 14 days for CTC. However, in the control samples incubated at 25 °C in the dark, concentrations of OTC, TC and CTC only decreased 64.7%, 66.7% and 73.3%, respectively, after 49 days. The degradation rates of TCs in the composting feedstock were in the order of CTC > TC > OTC. During the composting process, CTC dissipated rapidly with the time required for 50% degradation (DT50) and 90% degradation (DT90) of 2.4 and 7.9 days, but OTC was more persistent with DT50 and DT90 values of 5.5 and 18.4 days. On the basis of the results obtained in this study, it could be concluded that pig manure-rice straw composting in a greenhouse can help to accelerate the degradation of TCs in pig manure and make composted residues safer for field application. This technology could be an acceptable practice for greenhouse farmers to utilize TCs-contaminated pig manure. PMID:26927136

  13. Degradation of Tetracyclines in Pig Manure by Composting with Rice Straw.

    PubMed

    Chai, Rushan; Huang, Lidong; Li, Lingling; Gielen, Gerty; Wang, Hailong; Zhang, Yongsong

    2016-02-24

    A holistic approach was followed for utilizing tetracyclines (TCs)-contaminated pig manure, by composting this with rice straw in a greenhouse for CO₂ fertilization and composted residue application. After composting, the composted residues can be applied to cropland as a supplemental source of synthetic fertilizers. The objective of this study was to determine the effect of pig manure-rice straw composting on the degradation of TCs in pig manure. The results showed that greenhouse composting significantly accelerated the degradation of TCs. Contents (150 mg·kg(-1)) of oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) in the composting feedstock could be completely removed within 42 days for OTC and TC, and 14 days for CTC. However, in the control samples incubated at 25 °C in the dark, concentrations of OTC, TC and CTC only decreased 64.7%, 66.7% and 73.3%, respectively, after 49 days. The degradation rates of TCs in the composting feedstock were in the order of CTC > TC > OTC. During the composting process, CTC dissipated rapidly with the time required for 50% degradation (DT50) and 90% degradation (DT90) of 2.4 and 7.9 days, but OTC was more persistent with DT50 and DT90 values of 5.5 and 18.4 days. On the basis of the results obtained in this study, it could be concluded that pig manure-rice straw composting in a greenhouse can help to accelerate the degradation of TCs in pig manure and make composted residues safer for field application. This technology could be an acceptable practice for greenhouse farmers to utilize TCs-contaminated pig manure.

  14. Antibiotic interactions with the hammerhead ribozyme:tetracyclines as a new class of hammerhead inhibitor.

    PubMed Central

    Murray, J B; Arnold, J R

    1996-01-01

    A screening of a range of common laboratory antibiotics for inhibition of the hammerhead ribozyme has shown that in addition to certain aminoglycosides (most notably neomycin B) the tetracyclines are also effective inhibitors, with chlorotetracycline being more effective than tetracycline. Inhibition by chlorotetracycline is not as strong as that by neomycin B but is more complicated, with at least two binding sites apparent. As with hammerhead inhibition by neomycin B, chlorotetracycline inhibition can be overcome by raising the concentration of the Mg2+ ion cofactor. We find that around six Mg2+ ions will displace neomycin B, compared with twelve for chlorotetracycline. Inhibition observed in the presence of mixtures of neomycin B and chlorotetracycline is consistent with separate binding sites on the hammerhead for these two classes of antibiotic. Under certain conditions of the mixing order and low concentration of chlorotetracycline, enhancement of single-turnover hammerhead cleavage by up to 20% is observed, with higher concentrations of antibiotic being inhibitory. We have also found that the presence of 2.5% (v/v) DMSO causes a 30% enhancement of the single-turnover cleavage. These results thus extend the range of known inhibitors of hammerhead cleavage, and also demonstrate how the cleavage can be accelerated. PMID:8760373

  15. Degradation of Tetracycline with BiFeO3 Prepared by a Simple Hydrothermal Method

    PubMed Central

    Xue, Zhehua; Wang, Ting; Chen, Bingdi; Malkoske, Tyler; Yu, Shuili; Tang, Yulin

    2015-01-01

    BiFeO3 particles (BFO) were prepared by a simple hydrothermal method and characterized. BFO was pure, with a wide particle size distribution, and was visible light responsive. Tetracycline was chosen as the model pollutant in this study. The pH value was an important factor influencing the degradation efficiency. The total organic carbon (TOC) measurement was emphasized as a potential standard to evaluate the visible light photocatalytic degradation efficiency. The photo-Fenton process showed much better degradation efficiency and a wider pH adaptive range than photocatalysis or the Fenton process solely. The optimal residual TOC concentrations of the photocatalysis, Fenton and photo-Fenton processes were 81%, 65% and 21%, while the rate constants of the three processes under the same condition where the best residual TOC was acquired were 9.7 × 10−3, 3.2 × 10−2 and 1.5 × 10−1 min−1, respectively. BFO was demonstrated to have excellent stability and reusability. A comparison among different reported advanced oxidation processes removing tetracycline (TC) was also made. Our findings showed that the photo-Fenton process had good potential for antibiotic-containing waste water treatment. It provides a new method to deal with antibiotic pollution. PMID:28793568

  16. Effects of crystallinity and surface modification of calcium phosphate nanoparticles on the loading and release of tetracycline hydro-chloride

    NASA Astrophysics Data System (ADS)

    Zhang, Huaizhi; Yan, Dong; Menike Korale Gedara, Sriyani; Dingiri Marakkalage, Sajith Sudeepa Fernando; Gamage Kasun Methlal, Jothirathna; Han, YingChao; Dai, HongLian

    2017-03-01

    The influences of crystallinity and surface modification of calcium phosphate nanoparticles (nCaP) on their drug loading capacity and drug release profile were studied in the present investigation. The CaP nanoparticles with different crystallinity were prepared by precipitation method under different temperatures. CaP nanoparticles with lower crystallinity exhibited higher drug loading capacity. The samples were characterized by XRD, FT-IR, SEM, TEM and BET surface area analyzer respectively. The drug loading capacity of nCaP was evaluated to tetracycline hydro-chloride (TCH). The internalization of TCH loaded nCaP in cancer cell was observed by florescence microscope. nCaP could be stabilized and dispersed in aqueous solution by poly(acrylic acid) surface modification agent, leading to enhanced drug loading capacity. The drug release was conducted in different pH environment and the experimental data proved that nCaP were pH sensitive drug carrier, suggesting that nCaP could achieve the controlled drug release in intracellular acidic environment. Furthermore, nCaP with higher crystallinity showed lower drug release rate than that of lower crystallinity, indicating that the drug release profile could be adjusted by crystallinity of nCaP. nCaP with adjustable drug loading and release properties are promising candidate as drug carrier for disease treatment.

  17. Denitrifying sulfide removal process on high-tetracycline wastewater.

    PubMed

    Liu, Chunshuang; Xu, Jian; Lee, Duu-Jong; Yu, Daoyong; Liu, Lihong

    2016-04-01

    Antibiotics wastewater from tetracycline (TC) production unit can have high levels of chemical oxygen demand, ammonium and sulfate and up to a few hundreds of milligrams per liter of TC. Denitrifying sulfide removal (DSR) process is set up for simultaneously removal of sulfur, carbon and nitrogen from waters. The DSR process was for the first time studied for treating TC wastewaters. The TC stress has no adverse effects on removal rates of nitrate and acetate; however, it moderately deteriorated sulfide removal rates and S(0) accumulation rates when the concentration is higher than 100mgL(-1) TC. The Thauera sp., and Pseudomonas sp. present the heterotrophs and Sulfurovum sp. presented the autotroph for the present DSR reactions. The high tolerance of TC stress by the tested consortium was explained by the excess production of extracellular polymeric substances at high TC concentration, which can bind with TC for minimizing its inhibition effects. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Genetic characterization of antibiotic resistance in enteropathogenic Escherichia coli carrying extended-spectrum beta-lactamases recovered from diarrhoeic rabbits.

    PubMed

    Poeta, P; Radhouani, H; Gonçalves, A; Figueiredo, N; Carvalho, C; Rodrigues, J; Igrejas, G

    2010-05-01

    A total of 52 Escherichia coli strains isolated from diarrhoeic rabbits were investigated for their enteropathogenic E. coli (EPEC) pathotype by PCR amplification of eae and bfp virulence genes. A total of 22 EPEC isolates were identified, serotyped and studied for antibiotic resistance and screened for the detection of extended-spectrum beta-lactamases (ESBLs). The EPEC isolates belonged to three serogroups (O26, O92 and O103). The most common serogroup (O103:K-:H2) was observed among 17 EPEC strains, the O92:K-serogroup in three isolates (the antibiotic sensitive ones) and the remaining O26:K-serogroup in two isolates (the ESBLs isolates). Resistances to ampicillin and tetracycline were the most frequent and detected followed by resistance to nalidixic acid, streptomycin, trimethoprim-sulphamethoxazole, cefoxitin, gentamicin and ciprofloxacin. All the isolates were sensitive for amikacin, ceftazidime, aztreonam, imipenem, chloramphenicol, tobramycin and amoxicillin + clavulanic acid. Two isolates recovered from two adult animals showed an intermediate susceptibility to cefotaxime, and a positive screening test for ESBL was demonstrated in both. The bla(TEM) gene was demonstrated in the majority of ampicillin-resistant isolates. The aac(3)-II or aac(3)-IV genes were detected in the four gentamicin-resistant isolates. In addition, the aadA gene was detected in 60% of streptomycin-resistant isolates. The tet(A) or tet(B) genes were identified in all tetracycline-resistant isolates. A total of nine EPEC isolates showed the phenotype SXT-resistant, and the sul1 and/or sul2 and/or sul3 genes were detected in all of them. Our findings showed that the molecular detection by the eae and bfp genes by PCR followed by serotyping is useful for monitoring trends in EPEC infections of rabbits allowing the identification of their possible reservoirs. The detection of genes involved in the resistance to antibiotics of different families in a relatively high proportion of faecal E

  19. Determination of five tetracyclines and their epimers by LC-MS/MS based on a liquid-liquid extraction with low temperature partitioning.

    PubMed

    Desmarchelier, Aurélien; Anizan, Sébastien; Minh Tien, Mai; Savoy, Marie-Claude; Bion, Cindy

    2018-04-01

    An LC-MS/MS method is presented for screening five tetracyclines and their epimers in a broad range of food products. The scope of matrices includes meat-, fish-, seafood-based products, various dairy ingredients, infant formulae and fats. The method principle is based on a liquid-liquid extraction with aqueous ethylenediaminetetraacetic acid (EDTA) and acetonitrile followed by a freezing step to promote phase separation at low temperature. After defatting with hexane, sample extracts were evaporated and reconstituted before injection onto the LC-MS/MS system. The addition of oxalic acid in the aqueous mobile phase was mandatory to maintain good peak shape and sensitivity over the run. The screening is based upon a double preparation of each sample, one 'as such' and a second one with the analytes spiked in the sample, in order to mitigate the risk of false negative response. The method was validated according to the European Community Reference Laboratories Residues Guidelines. A total of 93 samples were included in the validation by two independent laboratories giving both false-negative and false-positive rates at 0% for all compounds. Over the last two years, 2600 samples were analysed routinely and only one chicken sample was found above the regulatory limit.

  20. Antibacterial Activity of Cinoxacin In Vitro

    PubMed Central

    Giamarellou, Helen; Jackson, George G.

    1975-01-01

    Cinoxacin is a new synthetic compound similar chemically and in antimicrobial activity to oxolonic acid and nalidixic acid. It is most effective against Escherichia coli and Proteus mirabilis, but at concentrations expected in the urine it is inhibitory for all species of Enterobacteriaceae. Relative to nalidixic acid, cinoxacin has slightly greater inhibitory and bactericidal activity, less inoculum effect probably due to less heterogeneity in the susceptibility of bacterial cells, and less inhibition by high concentrations of serum protein. Both drugs are more active in an acid than an alkaline medium. Glucose can specifically antagonize the inhibitory effect against P. mirabilis. In urine the bactericidal rate and effect are decreased. Resistance to cinoxacin can be developed quickly by serial transfers in vitro. Some nonresistant organisms remained viable in bactericidal drug concentrations. The in vivo importance of the favorable features of cinoxacin must be determined by clinical trials. PMID:1096811

  1. Prophylactic tetracycline does not diminish the severity of epidermal growth factor receptor (EGFR) inhibitor-induced rash: results from the North Central Cancer Treatment Group (Supplementary N03CB).

    PubMed

    Jatoi, Aminah; Dakhil, Shaker R; Sloan, Jeff A; Kugler, John W; Rowland, Kendrith M; Schaefer, Paul L; Novotny, Paul J; Wender, Donald B; Gross, Howard M; Loprinzi, Charles L

    2011-10-01

    Previous studies suggest tetracycline and other antibiotics lessen the severity of epidermal growth factor receptor (EGFR) inhibitor-induced rash. This study sought to confirm such findings. Patients starting an EGFR inhibitor were eligible for this randomized, double-blinded, placebo-controlled study and had to be rash-free. They were then randomly assigned to tetracycline 500 mg orally twice a day for 28 days versus a placebo. Rash development and severity (monthly physician assessment and weekly patient-reported questionnaires), quality of life (SKINDEX-16), and adverse events were monitored during the 4-week intervention and then for an additional 4 weeks. The primary objective was to compare the incidence of grade 2 or worse rash between study arms; 32 patients per group provided a 90% probability of detecting a 40% difference in incidence with a type I error rate of 0.05 (two-sided). Sixty-five patients were enrolled, and groups were balanced on baseline characteristics. During the first 4 weeks, healthcare provider-reported data found that 27 tetracycline-treated patients (82%) and 24 placebo-exposed patients (75%) developed a rash. This rash was a grade 2+ in 17 (52%) and 14 (44%), respectively (p = 0.62). Comparable grade 2+ rash rates were observed during weeks 5 through 8 as well as with patient-reported rash data throughout the study period. Quality of life was comparable across study arms, and tetracycline was well tolerated. Although previous studies suggest otherwise, this randomized, double-blinded, placebo-controlled study did not find that tetracycline lessened rash incidence or severity in patients who were taking EGFR inhibitors.

  2. PROFILES OF GENE EXPRESSION ASSOCIATED WITH TETRACYCLINE OVER EXPRESSION OF HSP70 IN MCF-7 BREAST CANCER CELLS

    EPA Science Inventory

    Profiles of gene expression associated with tetracycline over expression of HSP70 in MCF-7 breast cancer cells.

    Heat shock proteins (HSPs) protect cells from damage through their function as molecular chaperones. Some cancers reveal high levels of HSP70 expression in asso...

  3. [New aspects of safety assessment and food contamination with antibiotics of tetracycline group in the light of harmonization of hygienic standards in Russia and Customs Union with the international standards].

    PubMed

    Onishchenko, G G; Sheveleva, S A; Khotimchenko, S A

    2012-01-01

    To address the issue of harmonization of Russian MRLs for tetracycline in food and on the basis of the tasks of preserving the value of hygienic standard for the more restrictive level than similar standards of the Codex Alimentarius Commission in this survey we analyzed the evidences of the negative effects of subingibitory amounts of these antibiotics (lying below the MIC for clinically relevant microorganisms). The inadequacy of the microbiological JECFA ADI and the necessity of using of methodology of analyzing the effects of biological active substances in small doses for assessing the risk of food contamination of tetracycline subingibitory concentrations were demonstrated. Current scientific information on the functions of antibiotics as signaling molecules in the microbial world and the role of tetracycline as a leading factor in the regulation of transcription in microorganisms and activation of the horizontal transfer of resistance genes transferred to the family of conjugative transposons Tn916-Tn1545 also was reviewed in paper. Evidence-based data regarding the basic contribution of subingibitory concentrations of tetracycline in the spread of worst transmissible type of antibiotic resistance and the formation of new pathogens, associated with it, are represented. To reduce the risk of direct adverse effects on microbial ecosystem in the human body and its habitat, and to minimize the indirect risk of new infections, the necessity of saving the current Russian level residues of tetracycline (< or = 0.01 mg/kg of product), which is low by contrast to the Codex MRLs (< or = 0.1-1.2 mg/kg), was proved. Tetracycline concentrations in food, regulated in Russian Federation, below 0.1 MIC for clinically significant microorganisms which aren't capable to initiation of the above described negative changes.

  4. The effect of EDTA, EGTA, EDTAC, and tetracycline-HCl with and without subsequent NaOCl treatment on the microhardness of root canal dentin.

    PubMed

    Sayin, Taner Cem; Serper, Ahmet; Cehreli, Zafer C; Otlu, Harika G

    2007-09-01

    The purpose of this study was to evaluate the effect of single and combined use of ethylenediamine tetra acetic acid (EDTA), ethylene glycol bis [b-aminoethylether] N,N,N',N'-tetraacetic acid (EGTA), EDTA plus Cetavlon (EDTAC), tetracycline-HCl, and NaOCl on the microhardness of root canal dentin. The crowns of 30 single-rooted human teeth were discarded at the cementoenamel junction and the roots were bisected longitudinally to obtain root halves (N = 60). The specimens were embedded in autopolymerizing acrylic resin, leaving the root canal dentin exposed. Dentin surfaces were prepared for microhardness test by grinding and polishing. The reference microhardness values of untreated specimens were recorded using a Vicker's microhardness tester at the apical, midroot, and cervical levels of the root canal. Thereafter, the specimens treated with single (test solution only) or combined (test solution, followed by 2.5% NaOCl) versions of the irrigants for 5 minutes. Posttreatment microhardness values were obtained as with initial ones. Statistical comparisons between the test groups and among single and combined treatments were carried out using 2-way ANOVA with repeated measures (P =.05). Comparisons within each group with respect to application regions were made with Friedman's nonparametric 2-way analysis of variance at the same level of significance. All treatment regimens except distilled water significantly decreased the microhardness of the root canal dentin (P < . 05). The single and combined use of EDTA decreased the microhardness of the root canal dentin significantly more than all other treatment regimens (P < .05). Compared with their single-treatment versions, all combined treatment regimens decreased the mean microhardness values significantly (P < .05). A comparison of single and combined treatment regimens revealed significant decreases only for EDTA and EDTA + NaOCl in the coronal region and for EDTAC and EDTAC + NaOCl in the apical and middle regions

  5. Prevalence, phenotypic and genetic diversity of Campylobacter in poultry fresh meat and poultry products on retail sale in Tuscany (Italy).

    PubMed

    Pedonese, Francesca; Nuvoloni, Roberta; Turchi, Barbara; Torracca, Beatrice; Di Giannatale, Elisabetta; Marotta, Francesca; Cerri, Domenico

    2017-03-31

    In this study, the prevalence of Campylobacter spp. in poultry fresh meat and ready‑to‑cook products was evaluated. Seventy‑three samples were collected at retail level from supermarkets and discount stores, obtaining 61.6% positivity. Of 133 Campylobacter isolates, 86 strains (Campylobacter coli, 58.1% and Campylobacter jejuni, 41.9%) were selected for characterisation on the basis of their SmaI and kpnI pulsed field gel‑electrophoresis (PFGE) profiles, to exclude clonal replicates. Campylobacters resulted highly resistant to tetracycline, ciprofloxacin, and nalidixic acid (79.1%, 72.1% and 65.1%, respectively); 50% of C. coli and 13.9% of C. jejuni were resistant to ciprofloxacin and erythromycin, the most important antimicrobials for human campylobacteriosis therapy. Five C. coli were resistant to 5/7 of the tested antimicrobials. HS4c was the prevailing C. jejuni serotype group (22.3%), whereas 8 other serotypes were identified in low percentages. SmaI and kpnI profiles showed a wide variability. The survey showed a high Campylobacter contamination of poultry meat and poultry products at retail level in Tuscany, Italy. A wide strains' heterogeneity and a remarkable level of strains' antimicrobial resistance have been reported, confirming the need for an improvement of specific preventive measures along the production chain.

  6. In vitro sensitivity of Hungarian Actinobaculum suis strains to selected antimicrobials.

    PubMed

    Biksi, I; Major, Andrea; Fodor, L; Szenci, O; Vetési, F

    2003-01-01

    In vitro antimicrobial sensitivity of 12 Hungarian isolates and the type strain ATCC 33144 of Actinobaculum suis to different antimicrobial compounds was determined both by the agar dilution and by the disc diffusion method. By agar dilution, MIC50 values in the range of 0.05-3.125 micrograms/ml were determined for penicillin, ampicillin, ceftiofur, doxycycline, tylosin, pleuromutilins, chloramphenicol, florfenicol, enrofloxacin and lincomycin. The MIC50 value of oxytetracycline and spectinomycin was 6.25 and 12.5 micrograms/ml, respectively. For ofloxacin, flumequine, neomycin, streptomycin, gentamicin, nalidixic acid, nitrofurantoin and sulphamethoxazole + trimethoprim MIC50 values were in the range of 25-100 micrograms/ml. With the disc diffusion method, all strains were sensitive to penicillin, cephalosporins examined, chloramphenicol and florfenicol, tetracyclines examined, pleuromutilins, lincomycin and tylosin. Variable sensitivity was observed for fluoroquinolones (flumequine, enrofloxacin, ofloxacin), most of the strains were susceptible to marbofloxacin. Almost all strains were resistant to aminoglycosides but most of them were sensitive to spectinomycin. A strong correlation was determined for disc diffusion and MIC results (Spearman's rho 0.789, p < 0001). MIC values of the type strain and MIC50 values of other tested strains did not differ significantly. Few strains showed a partially distinct resistance pattern for erythromycin, lincomycin and ampicillin in both methods.

  7. Prevalence and Characteristics of Salmonella and Campylobacter in Retail Poultry Meat in Japan.

    PubMed

    Furukawa, Ichiro; Ishihara, Tomoe; Teranishi, Hiroshi; Saito, Shioko; Yatsuyanagi, Jun; Wada, Eriko; Kumagai, Yuko; Takahashi, Shiho; Konno, Takayuki; Kashio, Hiroko; Kobayashi, Akihiko; Kato, Naoki; Hayashi, Ken-Ichi; Fukushima, Keisuke; Ishikawa, Kazuhiko; Horikawa, Kazumi; Oishi, Akira; Izumiya, Hidemasa; Ohnishi, Takahiro; Konishi, Yoshiko; Kuroki, Toshiro

    2017-05-24

    This study was performed to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Salmonella enterica subsp. enterica and Campylobacter spp. in poultry meat, and to analyze the association of genetic types of these bacteria with their geographical distribution and antimicrobial resistance profiles. Salmonella and Campylobacter isolates have been detected, respectively, in 54 and 71 samples out of 100 samples tested. Nine Salmonella serotypes were found, including S. enterica subsp. enterica serovar Infantis (33%), Schwarzengrund (12%), Manhattan (9%), and others. Campylobacter jejuni and C. coli were detected in 64 (64%) and 14 (14%) samples, respectively. S. enterica subsp. enterica isolates were very frequently resistant to tetracycline (78.3%) and streptomycin (68.3%). Many C. jejuni and C. coli isolates were resistant to sulfamethoxazole/trimethoprim (90.5%), nalidixic acid (47.3%), ampicillin (45.9%), and ciprofloxacin (40.5%). Cluster analysis was performed for the Salmonella isolates using pulsed-field gel electrophoresis (PFGE) data. For Campylobacter isolates, the cluster analysis was based on both PFGE and comparative genomic fingerprinting. The molecular typing results were compared with the information about antimicrobial resistance and geographical locations in which the poultry meat was produced. This analysis revealed that C. jejuni strains with a particular genotype and antimicrobial resistance profile are spreading in specific areas of Japan.

  8. [Characterization of Campylobacter jejuni samples coming form poultry meat and feces].

    PubMed

    Gutiérrez, Sindy; Orellana, Daniel; Martínez, Claudio; García Mena, Verónica

    2017-12-01

    Background Campylobacter jejuni is one of the main causal agents of food borne diseases. Infections with this pathogen are mainly caused by chicken meat consumption. Aim To characterize antibiotic resistance and virulence factors in C. jejuni strains obtained from chicken meat and poultry feces in Central Chile. Material and Methods The presence of C. jejuni in 30 meat and 40 feces samples from poultry was studied. From these samples, we obtained 40 strains which were characterized at the molecular level for the presence of 16 genes involved in virulence using PCR. In parallel, antibiotic resistance for ciprofloxacin, nalidixic acid, tetracycline, erythromycin, azithromycin, chloramphenicol y ampicillin was analyzed. Results Twenty and 63% of feces and chicken meat samples were positive for C. jejuni, respectively. Moreover, a high percentage of strains showed antibiotic resistance, where 27% of strains were resistant to all tested antibiotics, except for azithromycin. Finally, 10% of the strains coming from feces contained 14 out of 16 virulence genes evaluated. Only 23% of the strains did not contain any of these genes. Conclusions A high percentage of feces and chicken meat samples are contaminated with C. jejuni. Moreover, these strains show a high genetic and phenotypic diversity represented by their antibiotic resistance profiles and the presence of virulence factors.

  9. Genetically Similar Isolates of Salmonella enterica Serotype Enteritidis Persistent in China for a Long-Term Period.

    PubMed

    Song, Qifa; Shen, Xuanyi; Yang, Yuanbin; Zhang, Danyang; Gao, Hong

    2016-07-01

    Salmonella enterica serotype Enteritidis (S. Enteritidis) is an important causative agent of nontyphoidal salmonellosis in human populations. In this study, we collected 72 S. Enteritidis strains from 2004 to 2014 in Ningbo, mid-east China. Of the 72 strains, we identified a dominant clone of 58 strains recovered from patient's feces (n = 48), blood (n = 1), pleural effusion (n = 1), chickens (n = 3), and dessert cakes (n = 5) by pulsed-field gel electrophoresis (PFGE) and variable-number of tandem repeat analysis (MLVA). The profile arrangements of MLVA were SE1-SE2-SE3-SE5-SE6-SE8-SE9: 4-4-3-11-10-1-3. These dominant strains were susceptible to ampicillin, chloramphenicol, tetracycline, ciprofloxacin, gentamicin, cefotaxime and trimethoprim-sulfamethoxazole, and resistant to nalidixic acid. Additionally, all isolates harboured virulence genes invA, sipA, sopE, and spvB when tested by PCR. Our results reveal that genetically similar S. Enteritidis strains which accounted for several outbreaks as well as blood infection and pleural cavity infection are prevalent in China for a long-term period. This situation calls for further attention in the prevention and control of foodborne disease caused by Salmonella species. © 2016 Institute of Food Technologists®

  10. [Antimicrobial resistance of Salmonella spp isolated animal food for human consumption].

    PubMed

    Quesada, Adriana; Reginatto, Gabriel A; Ruiz Español, Ayelen; Colantonio, Lisandro D; Burrone, María Soledad

    2016-03-01

    To analyze all information available on antimicrobial-resistant Salmonella species isolated from foods of animal origin that are used for human consumption in Latin America. A systematic review of observational epidemiological studies conducted in Latin America between 2003 and 2014 was carried out using the PubMed and LILACS databases. Studies conducted as part of analyses of outbreaks or cases of human infection were not included. Three reviewers independently participated in the study selection. Additionally, the studies included underwent quality assessment. A total of 25 studies met the inclusion criteria. The studies included were conducted in Brazil, Mexico, Colombia, Argentina, and Venezuela. Salmonella spp. isolates were obtained mainly from animal-based foods derived from cattle, swine, and poultry, revealing that Salmonella typhimurium and S. enteritidis were the most frequently isolated serotypes (17 and 11 studies, respectively). In 23 studies, Salmonella spp. showed resistance to more than one antibiotic, including nalidixic acid, streptomycin, tetracycline, chloramphenicol, ampicillin, trimethoprim-sulfamethoxazole, gentamicin, ciprofloxacin, and cephalosporins. Salmonella spp. isolates obtained mainly from animal-based foods for human consumption in the countries analyzed often show resistance to several antibiotics. It is important that more countries in Latin America carry out and publish studies on Salmonella spp. resistance in order to establish and monitor adequate control strategies.

  11. On the use of the T-REx tetracycline-inducible gene expression system in vivo.

    PubMed

    Dobrovolsky, Vasily N; Heflich, Robert H

    2007-10-15

    Components of the commercially available T-REx system were used to create two types of transgenic mice. The first contained the tetracycline-repressor transgene under the control of the CMV promoter/enhancer; the second type contained a green fluorescent protein (GFP) reporter transgene under the control of the CMV promoter/enhancer with a tetracycline repressor operator sequence. Transgene expression was unpredictable in animals containing the individual transgenes. Animals with the reporter transgene expressed GFP in only some tissues (e.g., pancreas, kidney), and one line of reporter transgenic animals developed kidney disease, presumably due to expression of the transgene. The two types of transgenic animals were crossbred to produce double-transgenic animals with the object of regulating the expression of the reporter in vivo. When a similar double-transgenic system was constructed in cultured cells, the repressor protein suppressed the transcription of the reporter transgene. The presence of the repressor in double-transgenic animals had no effect on the expression of the reporter; double transgenic animals developed the same kidney disease that was seen in singly transgenic mice with the reporter. Our results indicate that transgenes under the control of the CMV promoter in the T-REx system express somewhat unpredictably and in only a limited number of tissues, making the use of this system for the development of in vivo models problematical. Copyright 2007 Wiley Periodicals, Inc.

  12. Feasibility of a tetracycline-binding method for detecting synovial fluid basic calcium phosphate crystals.

    PubMed

    Rosenthal, Ann K; Fahey, Mark; Gohr, Claudia; Burner, Todd; Konon, Irina; Daft, Laureen; Mattson, Eric; Hirschmugl, Carol; Ryan, Lawrence M; Simkin, Peter

    2008-10-01

    Basic calcium phosphate (BCP) crystals are common components of osteoarthritis (OA) synovial fluid. Progress in understanding the role of these bioactive particles in clinical OA has been hampered by difficulties in their identification. Tetracyclines stain calcium phosphate mineral in bone. The aim of this study was to investigate whether tetracycline staining might be an additional or alternative method for identifying BCP crystals in synovial fluid. A drop of oxytetracycline was mixed with a drop of fluid containing synthetic or native BCP, calcium pyrophosphate dihydrate (CPPD), or monosodium urate (MSU) crystals and placed on a microscope slide. Stained and unstained crystals were examined by light microscopy, with and without a portable broad-spectrum ultraviolet (UV) pen light. A small set of characterized synovial fluid samples were compared by staining with alizarin red S and oxytetracycline. Synthetic BCP crystals in synovial fluid were quantified fluorimetrically using oxytetracycline. After oxytetracycline staining, synthetic and native BCP crystals appeared as fluorescent amorphous aggregates under UV light. Oxytetracycline did not stain CPPD or MSU crystals or other particulates. Oxytetracycline staining had fewer false-positive test results than did alizarin red S staining and could provide estimates of the quantities of synthetic BCP crystals in synovial fluid. With further validation, oxytetracycline staining may prove to be a useful adjunct or alternative to currently available methods for identifying BCP crystals in synovial fluid.

  13. Direct quantification and distribution of tetracycline-resistant genes in meat samples by real-time polymerase chain reaction.

    PubMed

    Guarddon, Mónica; Miranda, Jose M; Vázquez, Beatriz I; Cepeda, Alberto; Franco, Carlos M

    2012-07-01

    The evolution of antimicrobial-resistant bacteria has become a threat to food safety and methods to control them are necessary. Counts of tetracycline-resistant (TR) bacteria by microbiological methods were compared with those obtained by quantitative PCR (qPCR) in 80 meat samples. TR Enterobacteriaceae counts were similar between the count plate method and qPCR (P= 0.24), whereas TR aerobic mesophilic bacteria counts were significantly higher by the microbiological method (P < 0.001). The distribution of tetA and tetB genes was investigated in different types of meat. tetA was detected in chicken meat (40%), turkey meat (100%), pork (20%), and beef (40%) samples, whereas tetB was detected in chicken meat (45%), turkey meat (70%), pork (30%), and beef (35%) samples. The presence of tetracycline residues was also investigated by a receptor assay. This study offers an alternative and rapid method for monitoring the presence of TR bacteria in meat and furthers the understanding of the distribution of tetA and tetB genes. © 2012 Institute of Food Technologists®

  14. Comparative Study on Antibiotic Resistance and DNA Profiles of Salmonella enterica Serovar Typhimurium Isolated from Humans, Retail Foods, and the Environment in Shanghai, China.

    PubMed

    Zhang, Zengfeng; Cao, Chenyang; Liu, Bin; Xu, Xuebin; Yan, Yanfei; Cui, Shenghui; Chen, Sheng; Meng, Jianghong; Yang, Baowei

    2018-05-09

    We characterized antibiotic resistance profiles, antibiotic resistance-associated genes, and pulsed-field gel electrophoresis (PFGE) patterns of 145 Salmonella enterica serotype Typhimurium isolates from human infections and retail foods that were possibly responsible for salmonellosis outbreaks from 2008 to 2012 in Shanghai, China. Resistance to at least three antibiotics was found in 66.7% of chicken isolates, 76.5% of duck isolates, 77.8% of pork isolates, and 80.5% of human isolates. Seven antibiotic resistance phenotypes were detected in chicken isolates, 16 in pork isolates, 17 in duck isolates, and 50 in human isolates. No significant difference (p > 0.05) was found between Salmonella isolates derived from human salmonellosis and from retail foods in terms of the percent resistance of ampicillin, amoxicillin/clavulanic acid, ceftiofur, ceftriaxone, nalidixic acid, chloramphenicol, gentamicin, kanamycin, streptomycin, tetracycline, sulfisoxazole, and sulfamethoxazole/trimethoprim. PFGE using XbaI and BlnI showed that some Salmonella isolates recovered from human infections and retail foods had same or highly similar genetic profile. Same or similar antibiotic resistance profiles, antibiotic resistance associated genes (i.e., qnrA, qnrB, qnrS, aac(6')-Ib, and oqxAB), gene cassettes (i.e., aadA2, dfrA12-aadA2, and aadA1), and mutations were detected in those isolates that exhibited high genetic similarities. These findings highlighted the frequent presence of Salmonella Typhimurium in retail chicken, pork, duck, and humans.

  15. Antimicrobial susceptibility and emerging resistance determinants (blaCTX-M, rmtB, fosA3) in clinical isolates from urinary tract infections in the Bolivian Chaco.

    PubMed

    Bartoloni, Alessandro; Sennati, Samanta; Di Maggio, Tiziana; Mantella, Antonia; Riccobono, Eleonora; Strohmeyer, Marianne; Revollo, Carmen; Villagran, Ana Liz; Pallecchi, Lucia; Rossolini, Gian Maria

    2016-02-01

    Bolivia is among the lowest-resourced South American countries, with very few data available on antibiotic resistance in bacterial pathogens. The phenotypic and molecular characterization of bacterial isolates responsible for urinary tract infections (UTIs) in the Bolivian Chaco are reported here. All clinical isolates from UTIs collected in the Hospital Basico Villa Montes between June 2010 and January 2014 were analyzed (N=213). Characterization included susceptibility testing, extended-spectrum beta-lactamase (ESBL) detection, identification of relevant resistance determinants (e.g., CTX-M-type ESBLs, 16S rRNA methyltransferases, glutathione S-transferases), and genotyping of CTX-M producers. Very high resistance rates were observed. Overall, the lowest susceptibility was observed for trimethoprim-sulphamethoxazole, tetracycline, nalidixic acid, amoxicillin-clavulanic acid, ciprofloxacin, and gentamicin. Of E. coli and K. pneumoniae, 11.6% were ESBL producers. Resistance to nitrofurantoin, amikacin, and fosfomycin remained low, and susceptibility to carbapenems was fully preserved. CTX-M-15 was the dominant CTX-M variant. Four E. coli ST131 (two being H30-Rx) were identified. Of note, isolates harbouring rmtB and fosA3 were detected. Bolivia is not an exception to the very high resistance burden affecting many South American countries. Optimization of alternative approaches to monitor local antibiotic resistance trends in resource-limited settings is strongly encouraged to support the implementation of effective empiric treatment guidelines. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Antibiotic resistance among Escherichia coli isolates from stool samples of children aged 3 to 14 years from Ujjain, India

    PubMed Central

    2013-01-01

    Background Antibiotic resistance is a major global public health concern, particularly in settings where few treatment options are available. Limited research has been done on antibiotic resistance in Escherichia coli of Indian children at community level. Therefore we studied antibiotic resistance patterns in E. coli isolates from stool samples of children aged 3-14 years from Ujjain, Central India, to investigate associations of resistance with demographic variables. Methods Children, 3-14 years of age, were included from 30 randomly selected villages of Palwa demographic surveillance site, Ujjain, India. Parents were interviewed using a questionnaire, and stool samples were collected from participating children. E. coli were isolated from stool samples (n = 529), and susceptibility testing to 18 different antibiotics was done using standard methods. Results The proportions of isolates resistant to various antibiotics were, nalidixic acid, (45%), tetracycline (37%), ampicillin (37%), sulfamethoxazole/trimethoprim (29%) and amoxicillin/clavulanic acid (29%). No isolates were resistant to imipenem. Overall, 72% of isolates were resistant to at least one antibiotic and 33% were multi-drug resistant. High rates of cross-resistance were seen for 15 (83%) of the antibiotics studied. E. coli isolates from children with literate mothers were more resistant to penicillins and fluoroquinolones. ESBL-producers comprised 9% of the isolates. Conclusion Antibiotic resistance and cross-resistance were common in E. coli from stools of children. Resistance rates were associated with maternal literacy. PMID:24124728

  17. The efficacy of ranitidine bismuth citrate, amoxicillin and doxycycline or tetracycline regimens as a first line treatment for Helicobacter pylori eradication.

    PubMed

    Akyildiz, Murat; Akay, Sinan; Musoglu, Ahmet; Tuncyurek, Muge; Aydin, Ahmet

    2009-01-01

    The eradication rates of Helicobacter pylori (H. pylori) clearly decreased with standard PPI-based triple therapies. To assess the efficacy of two different triple therapies consisting of ranitidine bismuth citrate-amoxicillin-doxycycline and ranitidine bismuth citrate-amoxicillin-tetracycline combinations as a first line treatment option. One hundred and fifteen consecutive dyspeptic patients in whom H. pylori infection was diagnosed for the first time were enrolled in this study. The patients were randomized into two groups. Group 1 (n=57) was assigned to receive a 14-day triple therapy consisting of ranitidine bismuth citrate 400 mg (b.i.d.), amoxicillin 1 g (b.i.d) and doxycycline 100 mg (b.i.d.). Group 2 (n=58) was assigned to receive a 14-day triple therapy consisting of ranitidine bismuth citrate 400 mg (b.i.d.), amoxicillin 1 g (b.i.d.) and tetracycline 500 mg (q.i.d.). The eradication was achieved in 45.7% (21/46) and 40.8% (20/49) of the patients in group 1 and group 2, according to per protocol analysis. The intention-to-treat eradication rates were 36.8% (21/57) and 34.5% (20/58) in group 1 and group 2, respectively. Two-week therapy with neither ranitidine bismuth citrate-amoxicillin-doxycycline nor ranitidine bismuth citrate-amoxicillin-tetracycline is adequately effective for H. pylori eradication as a first line therapy.

  18. Antimicrobial resistance profiles of common mastitis pathogens on Canadian dairy farms.

    PubMed

    Saini, V; McClure, J T; Léger, D; Keefe, G P; Scholl, D T; Morck, D W; Barkema, H W

    2012-08-01

    Monitoring of antimicrobial resistance (AMR) in bacteria has clinical and public health significance. The present study determined prevalence of AMR in common mastitis pathogens Staphylococcus aureus, including methicillin-resistant Staph. aureus (MRSA; n=1,810), Escherichia coli (n=394), and Klebsiella species (n=139), including extended-spectrum β-lactamase (ESBL)-producing E. coli and Klebsiella species, isolated from milk samples on 89 dairy farms in 6 Canadian provinces. Minimum inhibitory concentrations (MIC) were determined using the Sensititer bovine mastitis plate (Trek Diagnostic Systems Inc., Cleveland, OH) and a National Antimicrobial Resistance Monitoring System gram-negative panel containing antimicrobials commonly used for mastitis treatment and control. Denim blue chromogenic agar and real-time PCR were used to screen and confirm MRSA, respectively. Resistance proportion estimates ranged from 0% for cephalothin and oxacillin to 8.8% for penicillin in Staph. aureus isolates, and 15% of the resistant Staph. aureus isolates were multidrug resistant. One MRSA isolate was confirmed (prevalence: 0.05%). Resistance proportion estimates ranged from 0% for ceftriaxone and ciprofloxacin to 14.8% for tetracycline in E. coli, and 0% for amikacin, ceftiofur, ciprofloxacin, and nalidixic acid to 18.6% for tetracycline in Klebsiella species isolates. Further, 62.8 and 55% of the resistant E. coli and Klebsiella species isolates were multidrug resistant, respectively. Resistance to >5 and >2 antimicrobials was most common in E. coli and Klebsiella species isolates, respectively, and no ESBL producers were found. Prevalence of AMR in bovine mastitis pathogens was low. Most gram-negative udder pathogens were multidrug resistant; MRSA was rarely found, and ESBL E. coli and Klebsiella species isolates were absent in Canadian milk samples. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  19. Prevalence and Antimicrobial Resistance of Campylobacter Isolated from Dressed Beef Carcasses and Raw Milk in Tanzania

    PubMed Central

    Kashoma, Isaac P.; Kassem, Issmat I.; John, Julius; Kessy, Beda M.; Gebreyes, Wondwossen; Kazwala, Rudovick R.

    2016-01-01

    Campylobacter species are commonly transmitted to humans through consumption of contaminated foods such as milk and meat. The aim of this study was to investigate the prevalence, antimicrobial resistance, and genetic determinants of resistance of Campylobacter isolated from raw milk and beef carcasses in Tanzania. The antimicrobial resistance genes tested included blaOXA-61 (ampicillin), aph-3-1 (aminoglycoside), tet(O) (tetracycline), and cmeB (multi-drug efflux pump). The prevalence of Campylobacter was 9.5% in beef carcasses and 13.4% in raw milk, respectively. Using multiplex-polymerase chain reaction (PCR), we identified 58.1% of the isolates as Campylobacter jejuni, 30.7% as Campylobacter coli, and 9.7% as other Campylobacter spp. One isolate (1.6%) was positive for both C. jejuni and C. coli specific PCR. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method showed resistance to: ampicillin (63% and 94.1%), ciprofloxacin (9.3% and 11.8%), erythromycin (53.7% and 70.6%), gentamicin (0% and 15.7%), streptomycin (35.2% and 84.3%), and tetracycline (18.5% and 17.7%), respectively. Resistance to azithromycin (42.6%), nalidixic acid (64.8%), and chloramphenicol (13%) was determined using the disk diffusion assay only, while resistance to tylosin (90.2%) was quantified using the broth microdilution method. The blaOXA-61 (52.6% and 28.1%), cmeB (26.3% and 31.3%), tet(O) (26.3% and 31.3%), and aph-3-1 (5.3% and 3.0%) were detected in C. coli and C. jejuni. These findings highlight the extent of antimicrobial resistance in Campylobacter occurring in important foods in Tanzania. The potential risks to consumers emphasize the need for adequate control approaches, including the prudent use of antimicrobials to minimize the spread of antimicrobial-resistant Campylobacter. PMID:26153978

  20. Prevalence and Antimicrobial Resistance of Campylobacter Isolated from Dressed Beef Carcasses and Raw Milk in Tanzania.

    PubMed

    Kashoma, Isaac P; Kassem, Issmat I; John, Julius; Kessy, Beda M; Gebreyes, Wondwossen; Kazwala, Rudovick R; Rajashekara, Gireesh

    2016-01-01

    Campylobacter species are commonly transmitted to humans through consumption of contaminated foods such as milk and meat. The aim of this study was to investigate the prevalence, antimicrobial resistance, and genetic determinants of resistance of Campylobacter isolated from raw milk and beef carcasses in Tanzania. The antimicrobial resistance genes tested included blaOXA-61 (ampicillin), aph-3-1 (aminoglycoside), tet(O) (tetracycline), and cmeB (multi-drug efflux pump). The prevalence of Campylobacter was 9.5% in beef carcasses and 13.4% in raw milk, respectively. Using multiplex-polymerase chain reaction (PCR), we identified 58.1% of the isolates as Campylobacter jejuni, 30.7% as Campylobacter coli, and 9.7% as other Campylobacter spp. One isolate (1.6%) was positive for both C. jejuni and C. coli specific PCR. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method showed resistance to: ampicillin (63% and 94.1%), ciprofloxacin (9.3% and 11.8%), erythromycin (53.7% and 70.6%), gentamicin (0% and 15.7%), streptomycin (35.2% and 84.3%), and tetracycline (18.5% and 17.7%), respectively. Resistance to azithromycin (42.6%), nalidixic acid (64.8%), and chloramphenicol (13%) was determined using the disk diffusion assay only, while resistance to tylosin (90.2%) was quantified using the broth microdilution method. The blaOXA-61 (52.6% and 28.1%), cmeB (26.3% and 31.3%), tet(O) (26.3% and 31.3%), and aph-3-1 (5.3% and 3.0%) were detected in C. coli and C. jejuni. These findings highlight the extent of antimicrobial resistance in Campylobacter occurring in important foods in Tanzania. The potential risks to consumers emphasize the need for adequate control approaches, including the prudent use of antimicrobials to minimize the spread of antimicrobial-resistant Campylobacter.

  1. [Matrix effect and application of field-amplified sample injection in the analysis of four tetracyclines in waters by capillary electrohoresis].

    PubMed

    2014-08-01

    The system abilities of two chromatographic techniques, capillary electrophoresis (CE) and high performance liquid chromatography (HPLC), were compared for the analysis of four tetracyclines (tetracycline, chlorotetracycline, oxytetracycline and doxycycline). The pH, concentration of background electrolyte (BGE) were optimized for the analysis of the standard mixture sample, meanwhile, the effects of separation voltage and water matrix (pH value and hardness) effects were investigated. In hydrodynamic injection (HDI) mode, a good quantitative linearity and baseline separation within 9. 0 min were obtained for the four tetracyclines at the optimal conditions; the analytical time was about half of that of HPLC. The limits of detection (LODs) were in the range of 0. 28 - 0. 62 mg/L, and the relative standard deviations (RSDs) (n= 6) of migration time and peak area were 0. 42% - 0. 56% and 2. 24% - 2. 95%, respectively. The obtained recoveries spiked in tap water and fishpond water were at the ranges of 96. 3% - 107. 2% and 87. 1% - 105. 2%, respectively. In addition, the stacking method, field-amplified sample injection (FASI), was employed to improve the sensitivity, and the LOD was down to the range of 17.8-35.5 μg/L. With FASI stacking, the RSDs (n=6) of migration time and peak area were 0. 85%-0. 95% and 1. 69%-3.43%, respectively. Due to the advantages of simple sample pretreatment and fast speed, CE is promising in the analysis of the antibiotics in environmental water.

  2. Identification and Characterization of Fluoroquinolone Non-susceptible Streptococcus pyogenes Clones Harboring Tetracycline and Macrolide Resistance in Shanghai, China

    PubMed Central

    Shen, Yinfang; Cai, Jiehao; Davies, Mark R.; Zhang, Chi; Gao, Kun; Qiao, Dan; Jiang, Haoqin; Yao, Weilei; Li, Yuefang; Zeng, Mei; Chen, Mingliang

    2018-01-01

    Streptococcus pyogenes, also known as group A Streptococcus (GAS), is one of the top 10 infectious causes of death worldwide. Macrolide and tetracycline resistant GAS has emerged as a major health concern in China coinciding with an ongoing scarlet fever epidemic. Furthermore, increasing rates of fluoroquinolone (FQ) non-susceptibility within GAS from geographical regions outside of China has also been reported. Fluoroquinolones are the third most commonly prescribed antibiotic in China and is an therapeutic alternative for multi-drug resistant GAS. The purpose of this study was to investigate the epidemiological and molecular features of GAS fluoroquinolone (FQ) non-susceptibility in Shanghai, China. GAS (n = 2,258) recovered between 2011 and 2016 from children and adults were tested for FQ-non-susceptibility. Efflux phenotype and mutations in parC, parE, gyrA, and gyrB were investigated and genetic relationships were determined by emm typing, pulsed-field gel electrophoresis and phylogenetic analysis. The frequency of GAS FQ-non-susceptibility was 1.3% (30/2,258), with the phenotype more prevalent in GAS isolated from adults (14.3%) than from children (1.2%). Eighty percent (24/30) of FQ-non-susceptible isolates were also resistant to both macrolides (ermB) and tetracycline (tetM) including the GAS sequence types emm12, emm6, emm11, and emm1. Genomic fingerprinting analysis of the 30 isolates revealed that non-susceptibility may arise in various genetic backgrounds even within a single emm type. No efflux phenotype was observed in FQ non-susceptible isolates, and molecular analysis of the quinolone resistance-determining regions (QRDRs) identified several sequence polymorphisms in ParC and ParE, and none in GyrA and GyrB. Expansion of this analysis to 152 publically available GAS whole genome sequences from Hong Kong predicted 7.9% (12/152) of Hong Kong isolates harbored a S79F ParC mutation, of which 66.7% (8/12) were macrolide and tetracycline resistant

  3. Interaction of residue tetracycline hydrochloride in milk with β-galactosidase protein by multi-spectrum methods and molecular docking

    NASA Astrophysics Data System (ADS)

    Gao, Xin; Bi, Hongna; Zuo, Huijun; Jia, Jingjing; Tang, Lin

    2017-08-01

    The purpose of this study was to explore the effect of residue tetracycline hydrochloride (TCH) in milk on molecular structure and activity of β-Gal. Inhibition kinetics assay showed the TCH inhibited β-Gal activity reversibly in a competitive manner. In addition, differences in the activity of β-Gal in the absence and presence of TCH as a function of pH and temperature were found although the optimum pH and temperature of β-Gal remained similar. Fluorescence experiment results showed that TCH effectively quenched the intrinsic fluorescence of β-Gal via static quenching. Thermodynamic parameters delineated the major roles of electrostatic forces played between β-Gal and TCH. Additionally, synchronous fluorescence and circular dichroism spectra (CD spectra) results indicated the secondary structure of β-Gal was changed due to the formation of β-Gal-TCH complexes. The molecular docking further revealed that TCH interacted with some amino acid residues of β-Gal, affecting the active site of the enzyme and thus leading to change in enzyme activity. These alterations in conformation and activity of β-Gal should be taken into consideration while using β-Gal for producing oligosaccharide prebiotics on dairy industries.

  4. Interactions of the "piano-stool" [ruthenium(II)(η(6) -arene)(quinolone)Cl](+) complexes with water; DFT computational study.

    PubMed

    Zábojníková, Tereza; Cajzl, Radim; Kljun, Jakob; Chval, Zdeněk; Turel, Iztok; Burda, Jaroslav V

    2016-07-15

    Full optimizations of stationary points along the reaction coordinate for the hydration of several quinolone Ru(II) half-sandwich complexes were performed in water environment using the B3PW91/6-31+G(d)/PCM/UAKS method. The role of diffuse functions (especially on oxygen) was found crucial for correct geometries along the reaction coordinate. Single-point (SP) calculations were performed at the B3LYP/6-311++G(2df,2pd)/DPCM/saled-UAKS level. In the first part, two possible reaction mechanisms-associative and dissociative were compared. It was found that the dissociative mechanism of the hydration process is kinetically slightly preferred. Another important conclusion concerns the reaction channels. It was found that substitution of chloride ligand (abbreviated in the text as dechlorination reaction) represents energetically and kinetically the most feasible pathway. In the second part the same hydration reaction was explored for reactivity comparison of the Ru(II)-complexes with several derivatives of nalidixic acid: cinoxacin, ofloxacin, and (thio)nalidixic acid. The hydration process is about four orders of magnitude faster in a basic solution compared to neutral/acidic environment with cinoxacin and nalidixic acid as the most reactive complexes in the former and latter environments, respectively. The explored hydration reaction is in all cases endergonic; nevertheless the endergonicity is substantially lower (by ∼6 kcal/mol) in basic environment. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Inhibition of retinoic acid catabolism by minocycline: evidence for a novel mode of action?

    PubMed

    Regen, Francesca; Hildebrand, Martin; Le Bret, Nathalie; Herzog, Irmelin; Heuser, Isabella; Hellmann-Regen, Julian

    2015-06-01

    Retinoic acid (RA) represents an essential and highly potent endogenous retinoid with pronounced anti-inflammatory properties and potent anti-acne activity, and has recently been suggested to share a common anti-inflammatory mode of action with tetracycline antibiotics. We hypothesized that tetracyclines may directly interfere with RA homeostasis via inhibition of its local cytochrome P450 (CYP450)-mediated degradation, an essential component of tightly regulated skin RA homeostasis. To test this hypothesis, we performed controlled in vitro RA metabolism assays using rat skin microsomes and measured RA levels in a RA-synthesizing human keratinocyte cell line, both in the presence and in the absence of minocycline, a tetracycline popular in acne treatment. Interestingly, minocycline potently blocked RA degradation in rat skin microsomes, and strikingly enhanced RA levels in RA-synthesizing cell cultures, in a dose-dependent manner. These findings indicate a potential role for CYP-450-mediated RA metabolism in minocycline's pleiotropic mode of action and anti-acne efficacy and could account for the overlap between minocycline and RA-induced effects at the level of their molecular mode of action, but also clinically at the level of the rare side effect of pseudotumor cerebri, which is observed for both, RA and minocycline treatment. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Improved method for the on-line metal chelate affinity chromatography-high-performance liquid chromatographic determination of tetracycline antibiotics in animal products.

    PubMed

    Cooper, A D; Stubbings, G W; Kelly, M; Tarbin, J A; Farrington, W H; Shearer, G

    1998-07-03

    An improved on-line metal chelate affinity chromatography-high-performance liquid chromatography (MCAC-HPLC) method for the determination of tetracycline antibiotics in animal tissues and egg has been developed. Extraction was carried out with ethyl acetate. The extract was then evaporated to dryness and reconstituted in methanol prior to on-line MCAC clean-up and HPLC-UV determination. Recoveries of tetracycline, oxytetracycline, demeclocycline and chlortetracycline in the range 42% to 101% were obtained from egg, poultry, fish and venison tissues spiked at 25 micrograms kg-1. Limits of detection less than 10 microgram kg-1 were estimated for all four analytes. This method has higher throughput, higher recovery and lower limits of detection than a previously reported on-line MCAC-HPLC method which involved aqueous extraction and solid-phase extraction clean-up.

  7. Tetracycline antibiotics in hospital and municipal wastewaters: a pilot study in Portugal.

    PubMed

    Pena, A; Paulo, M; Silva, L J G; Seifrtová, M; Lino, C M; Solich, P

    2010-04-01

    This study investigated the occurrence of tetracyclines (TCs), namely minocycline (MIN), TC, and its epimer epitetracycline (ETC), and doxycycline (DC), in four hospital wastewater effluents and its fate in municipal wastewater treatment plants (WWTPs), in Coimbra, Portugal. Analytical determination was carried out by solid-phase extraction followed by liquid chromatography with fluorescence detection. A gradient system with a mobile phase containing oxalic acid 0.02 M and acetonitrile was used. After postcolumn derivatization with magnesium reagent, TCs were detected at lambda(exc) 386 nm and lambda(em) 500 nm. The proposed method allowed good sensitivity, accuracy, and precision. LOQs were 0.5 microg l(-1) for ETC and TC and 15 and 5 microg l(-1) for MIN and DC, respectively. The recovery values ranged between 66.4% and 117.1%, and intraday and interday repeatability was lower than 6.8%. The method was successfully used to determine the presence of the above-mentioned TCs in 24 wastewater composite samples obtained from hospital effluents and from influent and effluent of the WWTP located in Coimbra, Portugal. MIN and TC were found in 41.7% of the samples; ETC and DC were found in 25% and 8.3% of the samples, respectively. The levels found ranged from 6 to 531.7 microg l(-1) in hospital effluents, while its concentrations in WWTP ranged from 95.8 to 915.3 microg l(-1). A seasonal influence in the concentrations found has also been observed, the levels found in samples collected during spring being higher than those observed in samples collected during autumn; however, these are only preliminary results. The WWTP removal rate ranged between 89.5% and 100%.

  8. Tetracycline Resistance in the Subsurface of a Poultry Farm: Influence of Poultry Wastes

    NASA Astrophysics Data System (ADS)

    You, Y.; Ball, W. P.; Ward, M. J.; Hilpert, M.

    2007-12-01

    Concentrated animal feeding operations (CAFOs) are considered to be important man-made reservoir of antibiotic resistant bacteria. Using the electromagnetic induction (EMI) method of geophysical characterization, we measured the apparent subsurface electrical conductivity (ECa) at a CAFO site in order to assess the movement of pollutants associated with animal waste. The map of ECa and other available data suggest that (1) soil surrounding a poultry litter storage shed is contaminated by poultry waste, (2) a contamination plume in the subsurface emanates from that shed, and (3) the development of that plume is due to groundwater flow. We focused on understanding the spread of tetracycline resistance (Tc\\tiny R), because tetracycline is one of the most frequently used antibiotics in food animal production and therefore probably used at our field site. Microbiological experiments show the presence of Tc\\tiny R bacteria in the subsurface and indicate higher concentrations in the top soil than in the aquifer. Environmental DNA was extracted to identify CAFO- associated Tc\\tiny R genes and to explore a link between the presence of Tc\\tiny R and CAFO practices. A "shot-gun" cloning approach is under development to target the most prevalent Tc\\tiny R gene. This gene will be monitored in future experiments, in which we will study the transmission of Tc\\tiny R to naive E.~coli under selective pressure of Tc. Experimental results will be used to develop a mathematical/numerical model in order to describe the transmission process and to subsequently make estimates regarding the large-scale spread of antibiotic resistance.

  9. High Throughput Detection of Tetracycline Residues in Milk Using Graphene or Graphene Oxide as MALDI-TOF MS Matrix

    NASA Astrophysics Data System (ADS)

    Liu, Junyan; Liu, Yang; Gao, Mingxia; Zhang, Xiangmin

    2012-08-01

    In this work, a new pre-analysis method for tetracyclines (TCs) detection from the milk samples was established. As a good accomplishment for the existing accurate quantification strategies for TCs detection, the new pre-analysis method was demonstrated to be simple, sensitive, fast, cost effective, and high throughput, which would do a great favor to the routine quality pre-analysis of TCs from milk samples. Graphene or graphene oxide was utilized, for the first time, as a duel-platform to enrich and detect the TCs by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). All together, four TCs were chosen as models: tetracycline, oxytetracycline, demeclocycline, and chlortetracycline. Due to the excellent electronic, thermal, and mechanical properties, graphene and graphene oxide were successfully applied as matrices for MALDI-TOF MS with free background inference in low mass range. Meanwhile, graphene or graphene oxide has a large surface area and strong interaction force with the analytes. By taking the advantage of these features, TCs were effectively enriched with the limit of detection (LOD) as low as 2 nM.

  10. Application of a luminescent bacterial biosensor for the detection of tetracyclines in routine analysis of poultry muscle samples.

    PubMed

    Pikkemaat, M G; Rapallini, M L B A; Karp, M T; Elferink, J W A

    2010-08-01

    Tetracyclines are extensively used in veterinary medicine. For the detection of tetracycline residues in animal products, a broad array of methods is available. Luminescent bacterial biosensors represent an attractive inexpensive, simple and fast method for screening large numbers of samples. A previously developed cell-biosensor method was subjected to an evaluation study using over 300 routine poultry samples and the results were compared with a microbial inhibition test. The cell-biosensor assay yielded many more suspect samples, 10.2% versus 2% with the inhibition test, which all could be confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Only one sample contained a concentration above the maximum residue limit (MRL) of 100 microg kg(-1), while residue levels in most of the suspect samples were very low (<10 microg kg(-1)). The method appeared to be specific and robust. Using an experimental set-up comprising the analysis of a series of three sample dilutions allowed an appropriate cut-off for confirmatory analysis, limiting the number of samples and requiring further analysis to a minimum.

  11. Chemically modified tetracycline-3 (CMT-3): a novel inhibitor of the serine proteinase, elastase.

    PubMed

    Gu, Ying; Lee, Hsi-Ming; Simon, Sanford R; Golub, Lorne M

    2011-12-01

    Two classes of enzymes play an important role in connective tissue breakdown during various inflammatory diseases: serine proteinases and matrix metalloproteinases (MMPs). Tetracyclines (TCs) exhibit important anti-inflammatory and MMP-inhibitory properties that are unrelated to their antibacterial activities. Of the various TCs and their chemically modified NON-antibiotic analogs (CMTs) tested in vitro and in vivo, CMT-3 (6-demethyl-6-deoxy 4 de-dimethylamino tetracycline) has repeatedly been shown to be the most potent inhibitor of MMP activity and cytokine production. In addition to its anti-MMP function, we have shown that among all CMTs, CMT-3 is the only CMT that can also directly inhibit both the amidolytic activity of human leukocyte elastase (HLE, a serine proteinase) and the extracellular matrix degradation mediated by HLE. In addition, CMT-3 has been found to reduce leukocyte elastase activity in vivo in gingival extracts of rats with experimental periodontal disease. Thus, CMT-3 can inhibit pathologic connective tissue breakdown by (at least) two mechanisms: direct inhibition of neutral proteinases (elastase and MMPs); and protecting their endogenous inhibitors, α(1)-PI and TIMPs, from being digested and inactivated by MMPs and HLE, respectively. The pleiotropic properties of CMT-3 including (but not limited to) inhibition of serine proteinases, MMPs, and cytokines provide impressive therapeutic potential to reduce excessive connective tissue breakdown during various pathologic processes including inflammatory diseases, cancer metastasis and metabolic bone diseases. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Tetracycline removal from water by adsorption/bioadsorption on activated carbons and sludge-derived adsorbents.

    PubMed

    Rivera-Utrilla, José; Gómez-Pacheco, Carla V; Sánchez-Polo, Manuel; López-Peñalver, Jesús J; Ocampo-Pérez, Raúl

    2013-12-15

    The objective of this study was to analyze the behavior of activated carbons with different chemical and textural natures in the adsorption of three tetracyclines (TCs) (tetracycline, oxytetracycline, and chlortetracycline). We also assessed the influence of the solution pH and ionic strength on the adsorption of these compounds and studied their removal by the combined use of microorganisms and activated carbon (bioadsorption). Sludge-derived materials were also used to remove TC from water. The capacity of these materials to adsorb TC was very high and was much greater than that of commercial activated carbon. This elevated adsorption capacity (512.1-672.0 mg/g) is explained by the high tendency of TC to form complex ions with some of the metal ions present in these materials. The medium pH and presence of electrolytes considerably affected TCs adsorption on commercial activated carbon. These results indicate that electrostatic adsorbent-adsorbate interactions play an important role in TC adsorption processes when conducted at pH values that produce TC deprotonation. The presence of bacteria during the TCs adsorption process decreases their adsorption/bioadsorption on the commercial activated carbon, weakening interactions between the adsorbate and the microfilm formed on the carbon surface. The adsorptive capacity was considerably lower in dynamic versus static regime, attributable to problems of TC diffusion into carbon pores and the shorter contact time between adsorbate and adsorbent. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Optimization of tetracycline hydrochloride adsorption on amino modified SBA-15 using response surface methodology.

    PubMed

    Hashemikia, Samaneh; Hemmatinejad, Nahid; Ahmadi, Ebrahim; Montazer, Majid

    2015-04-01

    Several researchers are focused on preparation of mesoporous silica as drug carriers with high loading efficiency to control or sustain the drug release. Carriers with highly loaded drug are utilized to minimize the time of drug intake. In this study, amino modified SBA-15 was synthesized through grafting with amino propyl triethoxy silane and then loaded with tetracycline hydrochloride. The drug loading was optimized by using the response surface method considering various factors including drug to silica ratio, operation time, and temperature. The drug to silica ratio indicated as the most influential factor on the drug loading yield. Further, a quadratic polynomial equation was developed to predict the loading percentage. The experimental results indicated reasonable agreement with the predicted values. The modified and drug loaded mesoporous particles were characterized by FT-IR, SEM, TEM, X-ray diffraction (XRD), elemental analysis and N2 adsorption-desorption. The release profiles of tetracycline-loaded particles were studied in different pH. Also, Higuchi equation was used to analyze the release profile of the drug and to evaluate the kinetic of drug release. The drug release rate followed the conventional Higuchi model that could be controlled by amino-functionalized SBA-15. Further, the drug delivery system based on amino modified SBA-15 exhibits novel features with an appropriate usage as an anti-bacterial drug delivery system with effective management of drug adsorption and release. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Distribution of Oxytetracycline Resistance Plasmids between Aeromonads in Hospital and Aquaculture Environments: Implication of Tn1721 in Dissemination of the Tetracycline Resistance Determinant Tet A

    PubMed Central

    Rhodes, Glenn; Huys, Geert; Swings, Jean; Mcgann, Patrick; Hiney, Maura; Smith, Peter; Pickup, Roger W.

    2000-01-01

    Oxytetracycline-resistant (OTr) mesophilic aeromonads were recovered from untreated hospital effluent (72 isolates) and from fish farm hatchery tanks (91 isolates) at sites within the English Lake District, Cumbria, England. The transfer of OTr plasmids from these isolates was investigated. Using Escherichia coli J53-1 as a recipient, 11 isolates from the hospital site and 6 isolates from the fish farm site transferred OTr plasmids (designated pFBAOT1 to 17). Original isolates were identified using fatty acid methyl ester and fluorescent amplified fragment length polymorphism comparisons as either Aeromonas hydrophila HG3 (eight isolates), A. veronii b.v. sobria HG8 (six isolates), and A. caviae HGB5 (one isolate). One isolate remained unidentified, and one could not be assigned a taxonomic designation beyond the genus level. Plasmids pFBAOT1 to -17 were screened for the presence of the tetracycline resistance determinants Tet A to E and Tet G. Only determinant Tet A (10 plasmids) was detected in these plasmids, with 7 tet gene determinants remaining unclassified. In all cases, Tet A was located on a 5.5-kb EcoRI restriction fragment. Hybridization with inc-rep probes N, P, Q, W, and U showed pFBAOT3, -4, -5, -6, -7, -9, and -11, from the hospital environment, to be IncU plasmids. Further, restriction fragment length polymorphism (RFLP) analyses and DNA probing demonstrated that pFBAOT plasmids were closely related to IncU OTr plasmids pASOT, pASOT2, pASOT3, pRAS1 (originally isolated from A. salmonicida strains from fish farms in Scotland and Norway, respectively), and pIE420 (isolated from a German hospital E. coli strain). In addition, DNA analyses demonstrated that plasmids pRAS1 and pIE420 had identical RFLP profiles and that all fragments hybridized to each other. The presence of tetracycline resistance transposon Tn1721 in its entirety or in a truncated form in these plasmids was demonstrated. These results provided direct evidence that related tetracycline

  15. Sustained and localized in vitro release of BMP-2/7, RANKL, and tetracycline from FlexBone, an elastomeric osteoconductive bone substitute.

    PubMed

    Xu, Jianwen; Li, Xinning; Lian, Jane B; Ayers, David C; Song, Jie

    2009-10-01

    We tested the hypothesis that synthetic composites containing a high percentage of osteoconductive biominerals well-integrated with a hydrophilic polymer matrix can be engineered to provide both the structural and biochemical framework of a viable synthetic bone substitute. FlexBone, an elastic hydrogel-mineral composite exhibiting excellent structural integration was prepared by crosslinking poly(2-hydroxyethyl methacrylate) hydrogel in the presence of 25 wt% nanocrystalline hydroxyapatite and 25 wt% tricalcium phosphate. Biologically active factors tetracycline, BMP-2/7, and RANKL that stimulate bone formation and remodeling were encapsulated into FlexBone during polymerization or via postpolymerization adsorption. SEM and dynamic mechanical analyses showed that the encapsulation of tetracycline (5.0 wt%) did not compromise the structural integrity and compressive behavior of FlexBone, which could withstand repetitive megapascal-compressive loadings and be securely press-fitted into critical femoral defects. Dose-dependent, sustained in vitro release of tetracycline was characterized by spectroscopy and bacterial inhibition. A single dose of 40 ng BMP-2/7 or 10 ng RANKL pre-encapsulated with 50 mg FlexBone, released over 1 week, was able to induce local osteogenic differentiation of myoblast C2C12 cells and osteoclastogenesis of macrophage RAW264.7 cells, respectively. With a bonelike structural composition, useful surgical handling characteristics, and tunable biochemical microenvironment, FlexBone provides an exciting opportunity for the treatment of hard-to-heal skeletal defects with minimal systemic side effects. (c) 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  16. CeO2 /Bi2 WO6 Heterostructured Microsphere with Excellent Visible-light-driven Photocatalytic Performance for Degradation of Tetracycline Hydrochloride.

    PubMed

    Zhang, Fengjun; Zou, Shuang; Wang, Tianye; Shi, Yuxi; Liu, Peng

    2017-10-01

    CeO 2 /Bi 2 WO 6 heterostructured microsphere with excellent and stable photocatalytic activity for degradation tetracyclines was successfully synthesized via a facile solvothermal route. The photocatalytic experiments indicated that CeO 2 /Bi 2 WO 6 heterostructured microspheres exhibited enhanced photocatalytic activity compared to pure Bi 2 WO 6 in both the degradation of tetracycline hydrochloride (TCH) and rhodamine B (RhB) under visible-light irradiation. The 1CeO 2 /2Bi 2 WO 6 exhibited the best photocatalytic activity for degradation of TCH, reaching 91% after 60 min reaction. The results suggested that the particular morphological conformation of the microspheres resulted in smaller size and more uniform morphology so as to increase the specific surface area. Meanwhile, the heterojunction was formed by coupling CeO 2 and Bi 2 WO 6 in the as-prepared microspheres, so that the separation efficiency of photogenerated electrons and holes was dramatically improved and the lifetimes of charge carriers were prolonged. Hence, introduction of CeO 2 could significantly enhance the photocatalytic activity of CeO 2 /Bi 2 WO 6 heterostructured microspheres and facilitate the degradation of TCH. This work provided not only a principle method to synthesize CeO 2 /Bi 2 WO 6 with the excellent photocatalytic performance for actual produce, but also a excellent property of the photocatalyst for potential application in photocatalytic treatment of tetracyclines wastewater from pharmaceutical factory. © 2017 The American Society of Photobiology.

  17. Campylobacter Prevalence and Quinolone Susceptibility in Feces of Preharvest Feedlot Cattle Exposed to Enrofloxacin for the Treatment of Bovine Respiratory Disease.

    PubMed

    Smith, Ashley B; Renter, David G; Shi, Xiaorong; Cernicchiaro, Natalia; Sahin, Orhan; Nagaraja, T G

    2018-03-20

    Campylobacter spp. can be pathogenic to humans and often harbor antimicrobial resistance genes. Data on resistance in relation to fluoroquinolone use in beef cattle are scarce. This cross-sectional study of preharvest cattle evaluated Campylobacter prevalence and susceptibility to nalidixic acid and ciprofloxacin in feedlots that previously administered a fluoroquinolone as primary treatment for bovine respiratory disease. Twenty fresh fecal samples were collected from each of 10 pens, in each of five feedlots, 1-2 weeks before harvest. Feces were cultured for Campylobacter using selective enrichment and isolation methods. Genus and species were confirmed via PCR. Minimum inhibitory concentrations (MICs) of ciprofloxacin and nalidixic acid were determined using a micro-broth dilution method and human breakpoints. Antimicrobial use within each pen was recorded. Data were analyzed using generalized linear mixed-models (prevalence) and survival analysis (MICs). Overall, sample-level prevalence of Campylobacter was 27.2% (272/1000) and differed significantly among feedlots (p < 0.01). Campylobacter coli was the most common species (55.1%; 150/272), followed by Campylobacter hyointestinalis (42.6%; 116/272). Within-pen prevalence was not significantly associated with the number of fluoroquinolone treatments, sex, body weight, or metaphylaxis use, but was associated with the number of days cattle were in the feedlot (p = 0.03). The MICs for the majority of Campylobacter isolates were above the breakpoints for nalidixic acid (68.4%; 175/256) and for ciprofloxacin (65.6%; 168/256). Distributions of MICs for nalidixic acid (p ≤ 0.01) and ciprofloxacin (p ≤ 0.05) were significantly different among feedlots, and by Campylobacter species. However, fluoroquinolone treatments, sex, body weight, days on feed, and metaphylaxis were not significantly associated with MIC distributions within pens. We found no evidence that the number of fluoroquinolone treatments

  18. A Multi-Center Randomized Trial to Assess the Efficacy of Gatifloxacin versus Ciprofloxacin for the Treatment of Shigellosis in Vietnamese Children

    PubMed Central

    Vinh, Ha; Anh, Vo Thi Cuc; Anh, Nguyen Duc; Campbell, James I.; Hoang, Nguyen Van Minh; Nga, Tran Vu Thieu; Nhu, Nguyen Thi Khanh; Minh, Pham Van; Thuy, Cao Thu; Duy, Pham Thanh; Phuong, Le Thi; Loan, Ha Thi; Chinh, Mai Thu; Thao, Nguyen Thi Thu; Tham, Nguyen Thi Hong; Mong, Bui Li; Bay, Phan Van Be; Day, Jeremy N.; Dolecek, Christiane; Lan, Nguyen Phu Huong; Diep, To Song; Farrar, Jeremy J.; Chau, Nguyen Van Vinh; Wolbers, Marcel; Baker, Stephen

    2011-01-01

    Background The bacterial genus Shigella is the leading cause of dysentery. There have been significant increases in the proportion of Shigella isolated that demonstrate resistance to nalidixic acid. While nalidixic acid is no longer considered as a therapeutic agent for shigellosis, the fluoroquinolone ciprofloxacin is the current recommendation of the World Health Organization. Resistance to nalidixic acid is a marker of reduced susceptibility to older generation fluoroquinolones, such as ciprofloxacin. We aimed to assess the efficacy of gatifloxacin versus ciprofloxacin in the treatment of uncomplicated shigellosis in children. Methodology/Principal Findings We conducted a randomized, open-label, controlled trial with two parallel arms at two hospitals in southern Vietnam. The study was designed as a superiority trial and children with dysentery meeting the inclusion criteria were invited to participate. Participants received either gatifloxacin (10 mg/kg/day) in a single daily dose for 3 days or ciprofloxacin (30 mg/kg/day) in two divided doses for 3 days. The primary outcome measure was treatment failure; secondary outcome measures were time to the cessation of individual symptoms. Four hundred and ninety four patients were randomized to receive either gatifloxacin (n  =  249) or ciprofloxacin (n  =  245), of which 107 had a positive Shigella stool culture. We could not demonstrate superiority of gatifloxacin and observed similar clinical failure rate in both groups (gatifloxacin; 12.0% and ciprofloxacin; 11.0%, p  =  0.72). The median (inter-quartile range) time from illness onset to cessation of all symptoms was 95 (66–126) hours for gatifloxacin recipients and 93 (68–120) hours for the ciprofloxacin recipients (Hazard Ratio [95%CI]  =  0.98 [0.82–1.17], p  =  0.83). Conclusions We conclude that in Vietnam, where nalidixic acid resistant Shigellae are highly prevalent, ciprofloxacin and gatifloxacin are similarly effective for the

  19. Comparison of two modified coal ash ferric-carbon micro-electrolysis ceramic media for pretreatment of tetracycline wastewater.

    PubMed

    Yang, Kunlun; Jin, Yang; Yue, Qinyan; Zhao, Pin; Gao, Yuan; Wu, Suqing; Gao, Baoyu

    2017-05-01

    Application of modified sintering ferric-carbon ceramics (SFC) and sintering-free ferric-carbon ceramics (SFFC) based on coal ash and scrap iron for pretreatment of tetracycline (TET) wastewater was investigated in this article. Physical property, morphological character, toxic metal leaching content, and crystal component were studied to explore the application possibility of novel ceramics in micro-electrolysis reactors. The influences of operating conditions including influent pH, hydraulic retention time (HRT), and air-water ratio (A/W) on the removal of tetracycline were studied. The results showed that SFC and SFFC were suitable for application in micro-electrolysis reactors. The optimum conditions of SFC reactor were pH of 3, HRT of 7 h, and A/W of 10. For SFFC reactor, the optimum conditions were pH of 2, HRT of 7 h, and A/W of 15. In general, the TET removal efficiency of SFC reactor was better than that of SFFC reactor. However, the harden resistance of SFFC was better than that of SFC. Furthermore, the biodegradability of TET wastewater was improved greatly after micro-electrolysis pretreatment for both SFC and SFFC reactors.

  20. Monitoring of drug resistance amplification and attenuation with the use of tetracycline-resistant bacteria during wastewater treatment

    NASA Astrophysics Data System (ADS)

    Harnisz, Monika; Korzeniewska, Ewa; Niestępski, Sebastian; Osińska, Adriana; Nalepa, Beata

    2017-11-01

    The objective of this study was to monitor changes (amplification or attenuation) in antibiotic resistance during wastewater treatment based on the ecology of tetracycline-resistant bacteria. The untreated and treated wastewater were collected in four seasons. Number of tetracycline-(TETR) and oxytetracycline-resistant (OTCR) bacteria, their qualitative composition, minimum inhibitory concentrations (MICs), sensitivity to other antibiotics, and the presence of tet (A, B, C, D, E) resistance genes were determined. TETR and OTCR counts in untreated wastewater were 100 to 1000 higher than in treated effluent. OTCR bacterial counts were higher than TETR populations in both untreated and treated wastewater. TETR isolates were not dominated by a single bacterial genus or species, whereas Aeromonas hydrophila and Aeromonas sobria were the most common in OTCR isolates. The treatment process attenuated the drug resistance of TETR bacteria and amplified the resistance of OTCR bacteria. In both microbial groups, the frequency of tet(A) gene increased in effluent in comparison with untreated wastewater. Our results also indicate that treated wastewater is a reservoir of multiple drug-resistant bacteria as well as resistance determinants which may pose a health hazard for humans and animals when released to the natural environment.

  1. Oxidation of tetracycline antibiotics induced by Fe(III) ions without light irradiation.

    PubMed

    Wang, Hui; Yao, Hong; Sun, Peizhe; Pei, Jin; Li, Desheng; Huang, Ching-Hua

    2015-01-01

    The presence of Fe(III) ions was found to induce degradation of three tetracycline antibiotics (TCs), tetracycline (TTC), oxytetracycline (OTC) and chlorotetracycline (CTC), in aqueous solutions without light. The presence of Fe(III) promoted the degradation of TCs in most experimental pH (5.0, 7.0 and 9.0) except at pH 9.0 for CTC. Degradation rate constants of TTC, OTC and CTC reached maximum ((6.2±0.5)×10(-3) h(-1), (10.6±0.1)×10(-3) h(-1) and (15.9±0.5)×10(-3) h(-1) at pH 7.0, 20 °C) when Fe(III):TC molar ratio was 1:1, 1:1 and 2:1, respectively. Such metal-to-ligand ratios agreed well with the most favorable complexation between Fe(III) and each TC. Compared to without metals, Fe(III) enhanced the degradation rate of TTC, OTC and CTC by up to 20.67, 7.07 and 2.30 times, respectively, in clean water matrix, and also promoted degradation of TCs in real surface water and wastewater matrices. The promoted degradation likely occurred via complexation of TCs and subsequent oxidation by Fe(III). Degradation results of CTC versus 4-epi-CTC suggested Fe(III) likely binds to TCs' C4 dimethylamino group. Toxicity of the complexes evaluated using Photobacterium phosphoreum T3 was increased after several hours of reaction, suggesting the transformation products may exert a stronger toxicity than parent TCs. This study identifies new oxidative transformation of TCs induced by Fe(III) ions without light irradiation, further supporting the important role of iron species in the environmental fate of TCs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Immobilization of tetracyclines in manure and manure-amended soils using aluminum-based drinking water treatment residuals.

    PubMed

    Punamiya, Pravin; Sarkar, Dibyendu; Rakshit, Sudipta; Elzinga, Evert J; Datta, Rupali

    2016-02-01

    Veterinary antibiotics (VAs) are emerging contaminants of concern in the environment, mainly due to the potential for development of antibiotic-resistant bacteria and effect on microbiota that could interfere with crucial ecosystem functions such as nutrient cycling and decomposition. High levels of VAs such as tetracyclines (TCs) have been reported in agricultural soils amended with manure, which also has the potential to cause surface and groundwater contamination. Several recent studies have focused on developing methods to immobilize VAs such as composting with straw, hardwood chips, commercial biochar, aeration, mixing, heat treatment, etc. The major shortcomings of these methods include high cost and limited effectiveness. In the current study, we assessed the effectiveness of aluminum-based drinking water treatment residuals (Al-WTR) as a "green" sorbent to immobilize TCs in manure and manure-applied soils with varying physicochemical properties by laboratory incubation study. Results show that Al-WTR is very effective in immobilizing tetracycline (TTC) and oxytetracycline (OTC). The presence of phosphate resulted in significant (p < 0.01) decrease in TTC/OTC sorption by Al-WTR, but the presence of sulfate did not. attenuated total reflection (ATR)-FTIR spectroscopy indicate that TTC and OTC likely forming surface complexes via inner-sphere-type bonds in soils, manure, and manure-applied soils amended with Al-WTR.

  3. Rapid startup of thermophilic anaerobic digester to remove tetracycline and sulfonamides resistance genes from sewage sludge.

    PubMed

    Xu, Rui; Yang, Zhao-Hui; Wang, Qing-Peng; Bai, Yang; Liu, Jian-Bo; Zheng, Yue; Zhang, Yan-Ru; Xiong, Wei-Ping; Ahmad, Kito; Fan, Chang-Zheng

    2018-01-15

    Spread of antibiotic resistance genes (ARGs) originating from sewage sludge is highlighted as an eminent health threat. This study established a thermophilic anaerobic digester using one-step startup strategy to quickly remove tetracycline and sulfonamides resistance genes from sewage sludge. At least 20days were saved in the startup period from mesophilic to thermophilic condition. Based on the results of 16S rDNA amplicons sequencing and predicted metagenomic method, the successful startup largely relied on the fast colonization of core thermophilic microbial population (e.g. Firmicutes, Proteobacteria, Actinobacteria). Microbial metabolic gene pathways for substrate degradation and methane production was also increased by one-step mode. In addition, real-time quantitative PCR approach revealed that most targeted tetracycline and sulfonamides resistance genes ARGs (sulI, tetA, tetO, tetX) were substantially removed during thermophilic digestion (removal efficiency>80%). Network analysis showed that the elimination of ARGs was attributed to the decline of their horizontal (intI1 item) and vertical (potential hosts) transfer-related elements under high-temperature. This research demonstrated that rapid startup thermophilic anaerobic digestion of wastewater solids would be a suitable technology for reducing quantities of various ARGs. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Occurrence and Diversity of Tetracycline Resistance Genes in Lagoons and Groundwater Underlying Two Swine Production Facilities

    USGS Publications Warehouse

    Chee-Sanford, J. C.; Aminov, R.I.; Krapac, I.J.; Garrigues-Jeanjean, N.; Mackie, R.I.

    2001-01-01

    In this study, we used PCR typing methods to assess the presence of tetracycline resistance determinants conferring ribosomal protection in waste lagoons and in groundwater underlying two swine farms. All eight classes of genes encoding this mechanism of resistance [tet(O), tet(Q), tet(W), tet(M), tetB(P), tet(S), tet(T), and otrA] were found in total DNA extracted from water of two lagoons. These determinants were found to be seeping into the underlying groundwater and could be detected as far as 250 m downstream from the lagoons. The identities and origin of these genes in groundwater were confirmed by PCR-denaturing gradient gel electrophoresis and sequence analyses. Tetracycline-resistant bacterial isolates from groundwater harbored the tet(M) gene, which was not predominant in the environmental samples and was identical to tet(M) from the lagoons. The presence of this gene in some typical soil inhabitants suggests that the vector of antibiotic resistance gene dissemination is not limited to strains of gastrointestinal origin carrying the gene but can be mobilized into the indigenous soil microbiota. This study demonstrated that tet genes occur in the environment as a direct result of agriculture and suggested that groundwater may be a potential source of antibiotic resistance in the food chain.

  5. Promotion of Germination Using Hydroxamic Acid Inhibitors of 9-cis-Epoxycarotenoid Dioxygenase

    PubMed Central

    Awan, Sajjad Z.; Chandler, Jake O.; Harrison, Peter J.; Sergeant, Martin J.; Bugg, Timothy D. H.; Thompson, Andrew J.

    2017-01-01

    Abscisic acid (ABA) inhibits seed germination and the regulation of ABA biosynthesis has a role in maintenance of seed dormancy. The key rate-limiting step in ABA biosynthesis is catalyzed by 9-cis-epoxycarotenoid dioxygenase (NCED). Two hydroxamic acid inhibitors of carotenoid cleavage dioxygenase (CCD), D4 and D7, previously found to inhibit CCD and NCED in vitro, are shown to have the novel property of decreasing mean germination time of tomato (Solanum lycopersicum L.) seeds constitutively overexpressing LeNCED1. Post-germination, D4 exhibited no negative effects on tomato seedling growth in terms of height, dry weight, and fresh weight. Tobacco (Nicotiana tabacum L.) seeds containing a tetracycline-inducible LeNCED1 transgene were used to show that germination could be negatively and positively controlled through the chemical induction of gene expression and the chemical inhibition of the NCED protein: application of tetracycline increased mean germination time and delayed hypocotyl emergence in a similar manner to that observed when exogenous ABA was applied and this was reversed by D4 when NCED expression was induced at intermediate levels. D4 also improved germination in lettuce (Lactuca sativa L.) seeds under thermoinhibitory temperatures and in tomato seeds imbibed in high osmolarity solutions of polyethylene glycol. D4 reduced ABA and dihydrophaseic acid accumulation in tomato seeds overexpressing LeNCED1 and reduced ABA accumulation in wild type tomato seeds imbibed on polyethylene glycol. The evidence supports a mode of action of D4 through NCED inhibition, and this molecule provides a lead compound for the design of NCED inhibitors with greater specificity and potency. PMID:28373878

  6. Development of a rapid biolistic assay to determine changes in relative levels of intracellular calcium in leaves following tetracycline uptake by pinto bean plants.

    PubMed

    Farkas, Michael H; Mojica, Elmer-Rico E; Patel, Minesh; Aga, Diana S; Berry, James O

    2009-08-01

    Tetracycline antibiotics, such as chlortetracycline (CTC) and tetracycline (TC), are introduced into agricultural lands through the application of manure as fertilizer. These compounds are phytotoxic to certain crop plants, including pinto beans (Phaseolus vulgaris), the species used for this investigation. While the mechanism of this toxicity is not yet understood, CTC is known to be a calcium chelator. We describe here a novel method to show that CTC is taken up by pinto bean plants and chelates calcium in leaves. Cameleon fusion proteins can provide qualitative and quantitative imaging of intracellular calcium levels, but current methodology requires stable transformation. Many plant species, including pinto beans, are not yet transformable using standard Agrobacterium-based protocols. To determine the role of calcium chelation in this plant, a rapid, biolistic method was developed to transiently express the cameleon protein. This method can easily be adapted to other plant systems. Our findings provide evidence that chelation of intracellular calcium by CTC is related to phytotoxic effects caused by this antibiotic in pinto beans. Root uptake of CTC and TC by pinto beans and their translocation to leaves were further verified by fluorescence spectroscopy and liquid chromatography/mass spectrometry, confirming results of the biolistic method that showed calcium chelation by tetracyclines in leaves.

  7. [Identification of lactic acid bacteria in commercial yogurt and their antibiotic resistance].

    PubMed

    Qin, Yuxuan; Li, Jing; Wang, Qiuya; Gao, Kexin; Zhu, Baoli; Lv, Na

    2013-08-04

    To identify lactic acid bacteria (LAB) in commercial yogurts and investigate their antibiotic resistance. LABs were cultured from 5 yogurt brands and the isolates were identified at the species level by 16S rRNA sequence. Genotyping was performed by repetitive extragenic palindromic PCR (rep-PCR). The sensitivity to 7 antibiotics was tested for all LAB isolates by Kirby-Bauer paper diffusion (K-B method). Meanwhile, 9 antibiotic resistance genes (ARGs), including erythromycin resistance genes (ermA and ermB) and tetracycline resistance genes (tetM, tetK, tetS, tetQ, tetO, tetL and tetW), were detected by PCR amplification in the identified LAB isolates. The PCR products were confirmed by sequencing. Total 100 LABs were isolated, including 23 Lactobacillus delbrueckii ssp. bulgaricus, 26 Lactobacillus casei, 30 Streptococcus thermophilus, 5 Lactobacillus acidophilus, 6 Lactobacillus plantarum, and 10 Lactobacillus paracasei. The drug susceptibility test shows that all 100 isolates were resistant to gentamicin and streptomycin, 42 isolates were resistant to vancomycin, and on the contrary all were sensitive to cefalexin, erythromycin, tetracycline and oxytetracycline. Moreover, 5 ARGs were found in the 28 sequencing confirmed isolates, ermB gene was detected in 8 isolates, tet K in 4 isolates, tetL in 2 isolates, tetM in 4 isolates, tetO in 2 isolates. erm A, tet S, tet Q and tet W genes were not detected in the isolates. Antibiotic resistance genes were found in 53.57% (15/28) sequenced isolates, 2 -3 antibiotic resistance genes were detected in 4 isolates of L. delbrueckii ssp. bulgaricus. Some LABs were not labeled in commercial yogurt products. Antibiotic resistance genes tend to be found in the starter culture of L. delbrueckii ssp. Bulgaricus and S. thermophilus. All the LAB isolates were sensitive to erythromycin and tetracycline, even though some carried erythromycin and/or tetracycline resistance genes. We proved again that LAB could carry antibiotic

  8. Pharmacokinetic-Pharmacodynamic Model To Evaluate Intramuscular Tetracycline Treatment Protocols To Prevent Antimicrobial Resistance in Pigs

    PubMed Central

    Ahmad, Amais; Græsbøll, Kaare; Christiansen, Lasse Engbo; Toft, Nils; Matthews, Louise

    2014-01-01

    High instances of antimicrobial resistance are linked to both routine and excessive antimicrobial use, but excessive or inappropriate use represents an unnecessary risk. The competitive growth advantages of resistant bacteria may be amplified by the strain dynamics; in particular, the extent to which resistant strains outcompete susceptible strains under antimicrobial pressure may depend not only on the antimicrobial treatment strategies but also on the epidemiological parameters, such as the composition of the bacterial strains in a pig. This study evaluated how variation in the dosing protocol for intramuscular administration of tetracycline and the composition of bacterial strains in a pig affect the level of resistance in the intestine of a pig. Predictions were generated by a mathematical model of competitive growth of Escherichia coli strains in pigs under specified plasma concentration profiles of tetracycline. All dosing regimens result in a clear growth advantage for resistant strains. Short treatment duration was found to be preferable, since it allowed less time for resistant strains to outcompete the susceptible ones. Dosing frequency appeared to be ineffective at reducing the resistance levels. The number of competing strains had no apparent effect on the resistance level during treatment, but possession of fewer strains reduced the time to reach equilibrium after the end of treatment. To sum up, epidemiological parameters may have more profound influence on growth dynamics than dosing regimens and should be considered when designing improved treatment protocols. PMID:25547361

  9. Molecular Modeling of the Binding Structures in the Interlayer Adsorption of a Tetracycline Antibiotic by Smectite Clays

    NASA Astrophysics Data System (ADS)

    Aristilde, L.

    2009-12-01

    A controlling factor in the fate of antibiotics in the environment is their sequestration in soil particles including clay minerals. Of special interest is the interlayer adsorption by smectite clays, which has been shown to influence both the bioavailability and persistence of antibiotics in the soil environment. However, the interlayer structures of the bound antibiotics, essential to an accurate understanding of the adsorption mechanisms, are not well understood. Molecular simulations of oxytetracycline (OTC) with a model montmorillonite (MONT) clay were performed to gain insights into these structures for tetracycline antibiotics. Monte Carlo simulations were used for explorations of the clay layer spacing required for the adsorption of the antibiotic under different hydration states of the clay interlayer; these preliminary results were validated with previous X-ray diffraction patterns obtained following sorption experiments of OTC with MONT. Molecular dynamics relaxation simulations were performed subsequently in order to obtain geometry-optimized structures of the binding conformations of the intercalated antibiotic in the model MONT layers. This study contributes to a mechanistic understanding of the factors controlling the interlayer adsorption of the tetracycline antibiotics by the expandable smectite clay minerals. Figure 1. Optimized Monte Carlo simulation cell of OTC in the interlayer of MONT: perspective side view (top) and bottom view (bottom).

  10. Purification of subunits of Escherichia coli DNA gyrase and reconstitution of enzymatic activity.

    PubMed

    Higgins, N P; Peebles, C L; Sugino, A; Cozzarelli, N R

    1978-04-01

    Extensively purified DNA gyrase from Escherichia coli is inhibited by nalidixic acid and by novobiocin. The enzyme is composed of two subunits, A and B, which were purified as separate components. Subunit A is the product of the gene controlling sensitivity to nalidixic acid (nalA) because: (i) the electrophoretic mobility of subunit A in the presence of sodium dodecyl sulfate is identical to that of the 105,000-dalton nalA gene product; (ii) mutants that are resistant to nalidixic acid (nalA(r)) produce a drug-resistant subunit A; and (iii) wild-type subunit A confers drug sensitivity to in vitro synthesis of varphiX174 DNA directed by nalA(r) mutants. Subunit B contains a 95,000-dalton polypeptide and is controlled by the gene specifying sensitivity to novobiocin (cou) because cou(r) mutants produce a novobiocin-resistant subunit B and novobiocin-resitant gyrase is made drug sensitive by wild-type subunit B. Subunits A and B associate, so that gyrase was also purified as a complex containing 105,000- and 95,000-dalton polypeptides. This enzyme and gyrase reconstructed from subunits have the same drug sensitivity, K(m) for ATP, and catalytic properties. The same ratio of subunits gives efficient reconstitution of the reactions intrinsic to DNA gyrase, including catalysis of supercoiling of closed duplex DNA, relaxation of supercoiled DNA in the absence of ATP, and site-specific cleavage of DNA induced by sodium dodecyl sulfate.

  11. Isolation of Salmonella from ready-to-eat poultry meat and evaluation of its survival at low temperature, microwaving and simulated gastric fluids.

    PubMed

    Akbar, Ali; Anal, Anil Kumar

    2015-05-01

    A study was conducted to evaluate the risk of Salmonella contamination and its survival at different stages in chill ready-to-eat poultry meat products chain. Samples (n = 181) were collected and examined for the presence of Salmonella species. The bacteria were initially identified against polyvalent antisera "O" and "H", followed by confirmation with 16 s rDNA. The single Salmonella, isolate from the tested food samples showed 99.8 % phylogenetic similarity with Salmonella enterica. It was further evaluated for antibiotic sensitivity pattern and found resistant to four antibiotics including ampicillin, chloramphenicol, tetracycline and nalidixic acid. Salmonella associated with ready-to-eat poultry meat products were found active at storage temperature ≥4 °C in a challenge study. It was revealed that shape and weight of the meat pieces have direct influence on the reduction of pathogens during microwave heating. The 30 and 60 s microwaving (with radiation power fixed at 900 W) was found ineffective for the elimination of target bacteria (10(6)-10(7) CFU/g) in meat pieces with weight ≥90 g. Salmonella enterica was able to survive in simulated gastric fluid. The storage temperature and microwaving were found critical point for the transfer of pathogens through ready-to-eat poultry meat products to consumer in chill ready-to-eat poultry meat chain.

  12. Epidemiological Characteristics and Clinical Treatment Outcome of Typhoid Fever in Ningbo, China, 2005-2014: Pulsed-Field Gel Electorophoresis Results Revealing Great Proportion of Common Transmission Sources.

    PubMed

    Song, Qifa; Yang, Yuanbin; Lin, Wenping; Yi, Bo; Xu, Guozhang

    2017-09-25

    We aimed to describe the molecular epidemiological characteristics and clinical treatment outcome of typhoid fever in Ningbo, China during 2005-2014. Eighty-eight Salmonella Typhi isolates were obtained from 307 hospitalized patients. Three prevalent pulsed-field gel electrophoresis (PFGE) patterns of 54 isolates from 3 outbreaks were identified. Overall, there were 64 (72.7%) isolates from clustered cases and 24 (27.3%) isolates from sporadic cases. Resistance to nalidixic acid (NAL) (n = 47; 53.4%) and ampicillin (AMP) (n = 40; 45.4%) and rare resistance to tetracycline (TET) (n = 2; 2.3%) and gentamicin (GEN) (n = 2; 2.3%) were observed. No isolates resistant to cefotaxime (CTX), chloramphenicol (CL), ciprofloxacin (CIP), and trimethoprim-sulfamethoxazole (SXT) were found. The occurrence of reduced sensitivity to CIP was 52.3% (n = 46). The medians of fever clearance time in cases with and without complications were 7 (interquartile range (IQR): 4-10) and 5 (IQR: 3-7) days (P = 0.001), respectively, when patients were treated with CIP or levofloxacin (LEV) and/or third-generation cephalosporins (CEP). Rates of serious complications were at low levels: peritonitis (2.3%), intestinal hemorrhage (6.8%), and intestinal perforation (1.1%). The present study revealed a long-term clustering trend with respect to PFGE patterns, occasional outbreaks, and the rapid spread of AMP resistance and decreased CIP susceptibility among S. Typhi isolates in recent years.

  13. Analysis of antimicrobial resistance genes in Aeromonas spp. isolated from cultured freshwater animals in China.

    PubMed

    Deng, Yu-Ting; Wu, Ya-Li; Tan, Al-Ping; Huang, Yu-Ping; Jiang, Lan; Xue, Hui-Juan; Wang, Wei-Li; Luo, Li; Zhao, Fei

    2014-08-01

    The development of resistance to antimicrobials used in aquatic animals is an increasing concern for aquaculture and public health. To monitor the occurrence of antimicrobial resistance and resistance genes in Aeromonas, a total of 106 isolates were collected from cultured freshwater animals in China from 1995 to 2012. Antimicrobial susceptibilities were determined by the disk diffusion method. The highest resistance percentage occurred with ampicillin, rifampin, streptomycin, and nalidixic acid. Most strains were sensitive to fluoroquinolones, doxycycline, cefotaxime, chloramphenicol, and amikacin. The isolates from turtle samples had the highest levels of resistance to 11 of the 12 tested antimicrobials when compared with those from fish or shrimp. Polymerase chain reaction and DNA sequence results showed that all trimethoprim/sulfamethoxazole-resistant strains contained sul1, and 37.0% were positive for tetA in tetracycline-resistant strains. ant(3″)-Ia was identified in 13 (24.5%) streptomycin-resistant strains. Plasmid-borne quinolone resistance genes were detected in five Aeromonas hydrophila (4.7%), two of which carried qnrS2, while the other three strains harbored aac(6')-Ib-cr. Two cefotaxime-resistant A. hydrophila were positive for bla(TEM-1) and bla(CTX-M-3). To our knowledge, this is the first report characterizing antimicrobial resistance in Aeromonas isolated from cultured freshwater animals in China, and providing resistance information of pathogen in Chinese aquaculture.

  14. Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

    PubMed Central

    Liu, Ping; Soupir, Michelle L.; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

    2011-01-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P < 0.0038) related to combined resistance to amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms. PMID:21821756

  15. Association of antibiotic resistance in agricultural Escherichia coli isolates with attachment to quartz.

    PubMed

    Liu, Ping; Soupir, Michelle L; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R

    2011-10-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P < 0.0038) related to combined resistance to amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms.

  16. Prevalence and antimicrobial resistance of Campylobacter species isolated from chicken carcasses during processing in Iran.

    PubMed

    Rahimi, E; Momtaz, H; Ameri, M; Ghasemian-Safaei, H; Ali-Kasemi, M

    2010-05-01

    The objective of this study was to determine the prevalence and antimicrobial resistance of Campylobacter spp. isolated from chicken carcasses during different stages of broiler processing in a major commercial poultry processing plant in southwestern Iran. Overall, 84 chicken carcasses were sampled from 4 sites along the processing line during a total of 7 visits. In addition, 14 water samples from the chiller tank were taken. Using the cultural method, 186 of 336 (55.4%) carcasses were positive for Campylobacter. Campylobacter jejuni was more frequently isolated (89.4%) than Campylobacter coli (10.6%). The frequency of Campylobacter spp. on carcasses was 54.8% after defeathering, 51.2% after evisceration, 69.0% 20 min after the chilling period started, and 46.4% 24 h after the chilling period completed. Campylobacter was positive in 85.7% of the samples taken from the chilling water. The frequency of Campylobacter spp.-positive carcasses was reduced in complete chilled chickens but not during the slaughtering process. Susceptibilities of Campylobacter isolates were determined for 10 antimicrobial drugs using the disk diffusion method. Of the 198 Campylobacter isolates tested, 92.9% were resistant to one or more antimicrobial agents. Resistance to tetracycline was the most common finding (78.3%), followed by resistance to ciprofloxacin (62.1%), nalidixic acid (58.6%), and enrofloxacin (44.4%).

  17. Prevalence, resistance patterns, and risk factors for antimicrobial resistance in bacteria from retail chicken meat in Colombia.

    PubMed

    Donado-Godoy, Pilar; Byrne, Barbara A; León, Maribel; Castellanos, Ricardo; Vanegas, Consuelo; Coral, Adriana; Arevalo, Alejandra; Clavijo, Viviana; Vargas, Mercedes; Romero Zuñiga, Juan J; Tafur, McAllister; Pérez-Gutierrez, Enrique; Smith, Woutrina A

    2015-04-01

    As a step toward implementing the Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS), this study aimed to establish the baseline antimicrobial resistance patterns of Salmonella serovars, Escherichia coli, and Enterococcus spp. isolates in retail poultry meat from independent stores and from a main chain distributor center. MICs of the isolates were determined for antimicrobials used both in humans and animals, using an automated system. Salmonella serovars were isolated from 26% of the meat samples and E. coli from 83%, whereas Enterococcus faecalis and Enterococcus faecium were detected in 81 and 13% of the meat samples, respectively. A principal finding of concern in this study was that almost 98% of isolates tested were multidrug resistant. Ceftiofur, enrofloxacin, nalidixic acid, and tetracycline were the antimicrobials that showed the highest frequency of resistance among Salmonella and E. coli isolates. For enterococci, 61.5% of E. faecium isolates were found to be resistant to quinupristin-dalfopristin; this is significant because it is used to treat nosocomial infections when vancomycin resistance is present. Vancomycin resistance was detected in 4% of the E. faecalis isolates. The results of our study highlight the need for rapid implementation of an integrated program for surveillance of antimicrobial resistance by the Colombian authorities in order to monitor trends, raise awareness, and help promote practices to safeguard later generation antimicrobial agents.

  18. Prevalence and distribution of Vibrio parahaemolyticus in finfish from Cochin (south India).

    PubMed

    Sudha, Santha; Divya, Puthenkandathil S; Francis, Bini; Hatha, Ammanamveetil A M

    2012-01-01

    Finfish samples obtained from four retail outlets in Cochin between June 2009 and June 2010 were investigated for the occurrence of Vibrio parahaemolyticus. A total of 182 samples were collected and suspect isolates were identified using standard biochemical tests and were further confirmed by a species-specific tlh gene. V. parahaemolyticus was detected in 45.1% of samples, with demersal fish being more affected than pelagic species. The bacterium was isolated more frequently from the skin and gills of pelagic fish, while the intestine yielded greater numbers of V. parahaemolyticus in demersal fish. The highest incidence of antibiotic resistance was recorded against ampicillin and streptomycin, followed by carbenicillin, cefpodoxime, cephalothin, colistin and amoxycillin; the lowest was against nalidixic acid, tetracycline, chloramphenicol and ciprofloxacin. Multiple drug resistance was prevalent among isolates. Although only a fraction of strains are pathogenic for humans, the time-temperature abuse in markets provides ample scope for these strains to multiply to dangerous levels. The multidrug resistant nature of the strains adds to the gravity of the problem. High V. parahaemolyticus incidence rates in market finfish samples from areas in and around Cochin clearly indicates that control measures should be adopted to reduce post-harvest contamination in seafood and time-temperature abuse in markets to diminish the risk of V. parahaemolyticus infection associated with seafood destined for human consumption.

  19. PREVALENCE AND ANTIMICROBIAL RESISTANCE OF SALMONELLA ISOLATED FROM CARCASSES, PROCESSING FACILITIES AND THE ENVIRONMENT SURROUNDING SMALL SCALE POULTRY SLAUGHTERHOUSES IN THAILAND.

    PubMed

    Chotinun, Suwit; Rojanasthien, Suvichai; Unger, Fred; Tadee, Pakpoom; Patchanee, Prapas

    2014-11-01

    Salmonella is a major food-borne pathogen worldwide, including Thai- land, and poultry meat plays a role as a vehicle for the spread of the disease from animals to humans. The prevalence and characteristics of Salmonella isolated from 41 small scale poultry slaughterhouses in Chiang Mai, Thailand were determined during July 2011 through May 2012. Salmonella's prevalence in live poultry, car- casses, waste water, and soil around processing plants were 3.2%, 7.3%, 22.0% and 29.0%, respectively. Eighteen different serotypes were identified, the most common being Corvallis (15.2%), followed by Rissen (13.9%), Hadar (12.7%), Enteritidis (10.1%), [I. 4,5,12:i:-] (8.8%), Stanley (8.8%), and Weltevreden (8.8%). Antimicrobial susceptibility tests revealed that 68.4% of the Salmonella spp were resistant to at least one antimicrobial while 50.6% showed multiple drug resis- tance (MDR). Specifically, 44.3% of Salmonella were resistant to nalidixic acid, followed by streptomycin (41.8%), ampicillin (34.2%), tetracycline (34.2%), and sulfamethoxazole/trimethoprim (20.3%). Salmonella contamination was found in processing lines, carcasses, and in the environment around the processing sta- tions. These findings indicate that improving hygiene management in small scale poultry slaughterhouses as well as prudent use of antimicrobial drugs is urgently needed if Salmonella contamination is to be reduced.

  20. Prevalence and antimicrobial resistance pattern of Salmonella in animal feed produced in Namibia.

    PubMed

    Shilangale, Renatus P; Di Giannatale, Elisabetta; Chimwamurombe, Percy M; Kaaya, Godwin P

    2012-01-01

    The occurrence of Salmonella is a global challenge in the public health and food production sectors. Our study investigated the prevalence, serovar and antimicrobial susceptibility of strains of Salmonella serovars isolated from animal feed (meat-and-bone and blood meal) samples from two commercial abattoirs in Namibia. A total of 650 samples (n=650) were examined for the presence of Salmonella. Results showed that 10.9% (n=71) were positive for Salmonella. Of the Salmonella serovars isolated, S. Chester was the most commonly isolated serovar (19.7%), followed by S. Schwarzengrund at 12.7%. From the Salmonella isolates, 19.7% (n=14) were resistant to one or more of the antimicrobials (nalidixic acid, trimethoprim-sulfamethoxazole, sulfisoxazole, streptomycin and/or tetracycline), whereas 80.3% (n=57) were susceptible to all 16 antimicrobials tested. Resistance to sulfisoxazole and the trimethroprimsuflamethoxazole combination were the most common. The resistant isolates belonged to ten different Salmonella serovars. The susceptibility of most of the Salmonella isolated to the antimicrobials tested indicates that anti-microbial resistance is not as common and extensive in Namibia as has been reported in many other countries. It also appears that there is a range of antimicrobials available that are effective in managing Salmonella infections in Namibia. However, there is some evidence that resistance is developing and this will need further monitoring to ensure it does not become a problem.

  1. Characterization of Four Multidrug Resistance Plasmids Captured from the Sediments of an Urban Coastal Wetland

    PubMed Central

    Botts, Ryan T.; Apffel, Brooke A.; Walters, C. J.; Davidson, Kelly E.; Echols, Ryan S.; Geiger, Michael R.; Guzman, Victoria L.; Haase, Victoria S.; Montana, Michal A.; La Chat, Chip A.; Mielke, Jenna A.; Mullen, Kelly L.; Virtue, Cierra C.; Brown, Celeste J.; Top, Eva M.; Cummings, David E.

    2017-01-01

    Self-transmissible and mobilizable plasmids contribute to the emergence and spread of multidrug-resistant bacteria by enabling the horizontal transfer of acquired antibiotic resistance. The objective of this study was to capture and characterize self-transmissible and mobilizable resistance plasmids from a coastal wetland impacted by urban stormwater runoff and human wastewater during the rainy season. Four plasmids were captured, two self-transmissible and two mobilizable, using both mating and enrichment approaches. Plasmid genomes, sequenced with either Illumina or PacBio platforms, revealed representatives of incompatibility groups IncP-6, IncR, IncN3, and IncF. The plasmids ranged in size from 36 to 144 kb and encoded known resistance genes for most of the major classes of antibiotics used to treat Gram-negative infections (tetracyclines, sulfonamides, β-lactams, fluoroquinolones, aminoglycosides, and amphenicols). The mobilizable IncP-6 plasmid pLNU-11 was discovered in a strain of Citrobacter freundii enriched from the wetland sediments with tetracycline and nalidixic acid, and encodes a novel AmpC-like β-lactamase (blaWDC-1), which shares less than 62% amino acid sequence identity with the PDC class of β-lactamases found in Pseudomonas aeruginosa. Although the IncR plasmid pTRE-1611 was captured by mating wetland bacteria with P. putida KT2440 as recipient, it was found to be mobilizable rather than self-transmissible. Two self-transmissible multidrug-resistance plasmids were also captured: the small (48 kb) IncN3 plasmid pTRE-131 was captured by mating wetland bacteria with Escherichia coli HY842 where it is seemed to be maintained at nearly 240 copies per cell, while the large (144 kb) IncF plasmid pTRE-2011, which was isolated from a cefotaxime-resistant environmental strain of E. coli ST744, exists at just a single copy per cell. Furthermore, pTRE-2011 bears the globally epidemic blaCTX-M-55 extended-spectrum β-lactamase downstream of ISEcp1. Our

  2. Antimicrobial Resistance in Non-Typhoidal Salmonella from Humans, Retail Meats and Food Animals: 2002-2007

    USDA-ARS?s Scientific Manuscript database

    Background. The National Antimicrobial Resistance Monitor System (NARMS) tracks antimicrobial susceptibility in enteric bacteria from humans, retail meats and food animals. We analyzed changes in ceftiofur resistance (TioR), nalidixic acid resistance (NalR) and multidrug resistance (MDR-AmpC, define...

  3. Occurrence of antimicrobial-resistant Escherichia coli and Salmonella enterica in the beef cattle production and processing continuum

    USDA-ARS?s Scientific Manuscript database

    Specific concerns have been raised that 3rd-generation cephalosporin-resistant (3GCr) Escherichia coli, trimethoprim-sulfamethoxazole-resistant (COTr) E. coli, 3GCr Salmonella enterica, and nalidixic acid-resistant (NALr) S. enterica, may be present in cattle production environments, persist through...

  4. The whitening effect of bleaching agents on tetracycline-stained rat teeth.

    PubMed

    Shin, D H; Summitt, J B

    2002-01-01

    This study compared the whitening effect of three bleaching agents on the teeth of rats and demonstrated differences in bleaching where dentin was exposed or enamel was thin. Thirty Albino rats were peritoneally injected with tetracycline solution daily for two weeks. Thirty-two disc-shaped specimens were cut from the crowns of incisors removed from sacrificed rats and were irradiated with UV light for 16 hours. Sections were stored in saline. Eight sections served as controls and were not bleached. Three bleaching agents (Opalescence, Rembrandt and Nite White) were applied to eight specimens each, five times a day for two weeks, and images of the sections were recorded at the following times: before bleaching (baseline), day 1, day 3, day 5, day 7, day 9, day 11 and day 14. Mean colors to demonstrate any change (deltaE) from baseline for each time period were as follows: control-9.78 (baseline), 9.17, 9.36, 9.65, 9.40, 9.99, 10.57, 11.36; Opalescence-10.08, (baseline) 7.63, 6.72, 6.04, 5.10, 4.87, 4.89, 4.27; Rembrandt-9.83 (baseline), 11.27, 9.55, 8.36, 7.75, 6.94, 7.11, 7.04; Nite White-10.44 (baseline), 9.92, 7.58, 6.80, 5.45, 5.05, 4.73, 4.01. All bleached teeth were lightened (p<.01). Another 56 tetracycline-stained rat incisors were UV irradiated for three days. Three different penetration depths were tested: penetration through lingual dentin and labial enamel (DN group), penetration through labial enamel only (RE group) and penetration through labial enamel covered with 1.0 mm human enamel (HE group). Specimens were bleached with Opalescence for one hour five times a day for one week or four weeks. A control group of unbleached teeth was also examined. Results (deltaE) were as follows: control--11.67; 1-week DN--13.55; 1-week RE--12.80; 1-week HE--12.07; 4-week DN--7.48; 4-week RE--7.50; 4-week HE--11.69. The color change in the 4-week DN and the 4-week RE groups showed the greatest reduction (p<.01).

  5. Alpha-2-Macroglobulin Levels in Gingival Crevicular Fluid Pre- and Post-scaling and Root Planing with Adjunctive Tetracycline Fibers in Chronic Periodontitis: A Randomized Controlled Trial.

    PubMed

    Chhina, Shivjot; Rathore, Ajit Singh; Juneja, Saurabh

    2015-06-01

    This split-mouth clinical study aimed to investigate levels of alpha-2-macroglobulin (a2M) in gingival crevicular fluid (GCF) of chronic periodontitis patients pre- and post-scaling and root planing (SRP) with or without adjunctive use of tetracycline fibers. In 30 patients of chronic periodontitis, samples of GCF were collected from the gingival sulcus before SRP. Recording of clinical parameters was conducted. This was followed by local drug delivery (LDD) of tetracycline fibers in test sites. In control sites, no LDD was done. Second samples of GCF were taken 90 days after treatment. Samples of crevicular fluid were analyzed to determine the levels of a2m. A gain of clinical attachment (CAL) of 3.30 mm for SRP and LDD and for SRP alone was 1.62 mm (p < 0.001). The pocket probing depth was significantly decreased by 2.43 mm for SRP and LDD and for SRP alone was 1.61 mm (p < 0.001) after 90 days. Alpha-2-macroglobulin was significantly reduced in GCF by SRP and SRP and LDD after 90 days (p < 0.001). Clinical and biochemical variables showed a more favorable outcome when SRP was combined with LDD of tetracycline fibers in management of patients suffering from chronic periodontitis.

  6. Detection of trace tetracycline in fish via synchronous fluorescence quenching with carbon quantum dots coated with molecularly imprinted silica

    NASA Astrophysics Data System (ADS)

    Yang, Ji; Lin, Zheng-Zhong; Nur, A.-Zha; Lu, Yan; Wu, Ming-Hui; Zeng, Jun; Chen, Xiao-Mei; Huang, Zhi-Yong

    2018-02-01

    A novel fluorescence-based sensor combining synchronous fluorescence spectroscopy (SFS) with molecularly imprinted polymers (MIPs) was fabricated with reverse microemulsion method. Tetracycline (TC), (3-aminopropyl) triethoxysilane (APTES), tetraethyl orthosilicate (TEOS) and carbon quantum dots (CDs) were used as template, functional monomer, cross-linker and signal sources respectively in the probe preparation. A synchronous fluorescence emission (λem) at 355 nm was observed for the prepared MIP-coated CDs (MIP@CDs) particles when the wavelength interval (Δλ) was set as 70 nm, and the synchronous fluorescence intensity could be rapidly and efficiently quenched by TC based on inner filter effect (IFE). The quenching efficiencies of synchronous fluorescence intensity was linearly fitted with tetracycline (TC) concentrations ranging from 0.1 to 50 μmol L- 1 with a detection limit (DL) of 9 nmol L- 1 (3σ, n = 9). The MIP@CDs was used as a probe to detect TC in fish samples with the recoveries ranging from 98.4% to 103.1% and the relative standard deviation less than 6.0%. The results illustrated that the as-prepared MIP@CDs could be applied to the detection of trace TC in fish samples with rapidity, high sensitivity and accuracy.

  7. The Essential Oil from Origanum vulgare L. and Its Individual Constituents Carvacrol and Thymol Enhance the Effect of Tetracycline against Staphylococcus aureus.

    PubMed

    Cirino, Isis Caroline S; Menezes-Silva, Suellen Maria P; Silva, Helena Tainá D; de Souza, Evandro Leite; Siqueira-Júnior, José P

    2014-01-01

    In an ongoing project to evaluate essential oils as modulators of antibiotic resistance, the essential oil from Origanum vulgare L. (OVEO), as well as its individual constituents carvacrol (CAR) and thymol (THY), were investigated using Staphylococcus aureus strains possessing efflux mechanisms of resistance to norfloxacin, erythromycin and tetracycline. The minimum inhibitory concentration (MIC) values of the antibiotics were determined by agar dilution method, in the absence and in the presence of subinhibitory concentrations of OVEO, CAR or THY. Along with relevant antistaphylococcal activity, OVEO, CAR and THY modulated the activity of tetracycline, i.e. in combination with antibiotics a reduction in the MIC was observed (up to fourfold). The results presented here represent, as far as we know, the first report of OVEO, CAR and THY as putative efflux pump inhibitors. Broadly, these findings indicate that essential oils could serve as potential sources of compounds capable of modulating drug resistance. © 2015 S. Karger AG, Basel.

  8. Efficient Removal of Tetracycline from Aqueous Media with a Fe3O4 Nanoparticles@graphene Oxide Nanosheets Assembly

    PubMed Central

    Hu, Xinjiang; Zhao, Yunlin; Wang, Hui; Tan, Xiaofei; Yang, Yuanxiu; Liu, Yunguo

    2017-01-01

    A readily separated composite was prepared via direct assembly of Fe3O4 magnetic nanoparticles onto the surface of graphene oxide (GO) (labeled as Fe3O4@GO) and used as an adsorbent for the removal of tetracycline (TC) from wastewater. The effects of external environmental conditions, such as pH, ionic strength, humic acid (HA), TC concentration, and temperature, on the adsorption process were studied. The adsorption data were analyzed by kinetics and isothermal models. The results show that the Fe3O4@GO composite has excellent sorptive properties and can efficiently remove TC. At low pH, the adsorption capacity of Fe3O4@GO toward TC decreases slowly with increasing pH value, while the adsorption capacity decreases rapidly at higher pH values. The ionic strength has insignificant effect on TC adsorption. The presence of HA affects the affinity of Fe3O4@GO to TC. The pseudo-second-order kinetics model and Langmuir model fit the adsorption data well. When the initial concentration of TC is 100 mg/L, a slow adsorption process dominates. Film diffusion is the rate limiting step of the adsorption. Importantly, Fe3O4@GO has good regeneration performance. The above results are of great significance to promote the application of Fe3O4@GO in the treatment of antibiotic wastewater. PMID:29194395

  9. Removal of organics and degradation products from industrial wastewater by a membrane bioreactor integrated with ozone or UV/H₂O₂ treatment.

    PubMed

    Laera, G; Cassano, D; Lopez, A; Pinto, A; Pollice, A; Ricco, G; Mascolo, G

    2012-01-17

    The treatment of a pharmaceutical wastewater resulting from the production of an antibacterial drug (nalidixic acid) was investigated employing a membrane bioreactor (MBR) integrated with either ozonation or UV/H(2)O(2) process. This was achieved by placing chemical oxidation in the recirculation stream of the MBR. A conventional configuration with chemical oxidation as polishing for the MBR effluent was also tested as a reference. The synergistic effect of MBR when integrated with chemical oxidation was assessed by monitoring (i) the main wastewater characteristics, (ii) the concentration of nalidixic acid, (iii) the 48 organics identified in the raw wastewater and (iv) the 55 degradation products identified during wastewater treatment. Results showed that MBR integration with ozonation or UV/H(2)O(2) did not cause relevant drawbacks to both biological and filtration processes, with COD removal rates in the range 85-95%. Nalidixic acid passed undegraded through the MBR and was completely removed in the chemical oxidation step. Although the polishing configuration appeared to give better performances than the integrated system in removing 15 out of 48 secondary organics while similar removals were obtained for 19 other compounds. The benefit of the integrated system was however evident for the removal of the degradation products. Indeed, the integrated system allowed higher removals for 34 out of 55 degradation products while for only 4 compounds the polishing configuration gave better performance. Overall, results showed the effectiveness of the integrated treatment with both ozone and UV/H(2)O(2).

  10. Efficient removal of tetracycline with KOH-activated graphene from aqueous solution

    PubMed Central

    Sun, Yiran; Yu, Fei

    2017-01-01

    Activated graphene absorbents with high specific surface area (SSA) were prepared by an easy KOH-activated method, and were applied in absorbing antibiotics, such as tetracycline (TC). After activation, many micropores were introduced to graphene oxide sheets, leading to higher SSA and many new oxygen-containing functional groups, which gave KOH-activated graphene excellent adsorption capacity (approx. 532.59 mg g−1) of TC. Further study on the adsorption mechanism showed that the Langmuir isotherm model and the pseudo-second-order kinetic model fitted with experiment data. To further understand the adsorption process, the effects of solid–liquid ratio, pH, ionic strength and coexisting ions were also investigated. The results revealed that, compared with pH and ionic strength, solid–liquid ratio and coexisting ions (Cu2+, CrO42−) had more significant influence over the adsorption performance. The findings provide guidance for application of KOH-activated graphene as a promising alternative adsorbent for antibiotics removal from aqueous solutions. PMID:29291064

  11. Impact of egg holding temperatures on the recovery of Salmonella from eggshells and stainless steel coupons

    USDA-ARS?s Scientific Manuscript database

    This experiment was conducted to determine the impact of egg holding temperature on the ability to recover Salmonella from eggshells after 24 h. Salmonella enterica Enteritidis (nalidixic acid resistant marker strain) inoculated eggshells and stainless steel coupons (SSC, 14 mm diameter) were held a...

  12. Effect of dietary bacteriophage supplementation in internal organs, fecal excretion and ileal immune response in laying hens challenged with salmonella enteritidis

    USDA-ARS?s Scientific Manuscript database

    A study was conducted to evaluate the role of bacteriophage (BP) against Salmonella enterica serovar Enteritidis (SE) internal organs colonization and ileum immune response in laying hens. Hens were challenged both orally and intracloacally with 108 cfu/mL cells of nalidixic acid resistant Salmonell...

  13. Testing of Experimental Compounds for Efficacy Against Leishmania

    DTIC Science & Technology

    1986-02-01

    pentamidine, formycin A, formycin B, amphotericin B, ketaconazole, 6- mercaptopurine riboside, adenosine, nalidixic acid, novobiocin, aphidicolin, 4-mercapto-lH... products of WR06026 as they can be identified and synthesized by officials at WRtAIR. 4. Perform secondary testing of especially promising compounds in

  14. Occurrence of tetracycline resistance genes in aquaculture facilities with varying use of oxytetracycline

    PubMed Central

    Seyfried, Erin E.; Newton, Ryan J.; Rubert, Kennedy F.; Pedersen, Joel A.; McMahon, Katherine D.

    2014-01-01

    The contribution of human activities to environmental reservoirs of antibiotic resistance is poorly understood. The purpose of this study was to determine if oxytetracycline (OTC) use in aquaculture facilities increased the detection frequency (i.e. prevalence) of tetracycline resistance genes relative to facilities with no recent OTC treatment. We used PCR to screen water and sediment from four non-commercial fish farms in northwestern Wisconsin for the presence of ten tetracycline resistance determinants (tetR): tet(A), tet(B), tet(D), tet(E), tet(G), tet(M), tet(O), tet(Q), tet(S) and tet(W). Water from farms with recent OTC use had significantly higher tetR detection frequencies than did water from farms without recent OTC use, with prevalence in raceways and rearing ponds of farms with recent OTC use exceeded by more than two-fold that of farms not using OTC. Effluent from all farms, regardless of treatment regime, had higher tetR detection frequencies than their corresponding influent for all genes, but the specific combinations of tetR genes detected in a sample were not different from their corresponding influent. Although OTC use was associated with the increased occurrence and diversity of tetR genes in water samples, it was not found to relate to tetR gene occurrence in sediment samples. Sediment samples from facilities with no recent OTC use had significantly higher frequencies of tetR gene detection than did samples from facilities with recent OTC use. All of the tetR genes were detected in both the medicated and non-medicated feed samples analyzed in this study. These findings suggest that both OTC treatment in aquaculture facilities, and the farms themselves, may be sources of tetR gene introduction to the environment. To our knowledge, this is the first study to use genotypic and cultivation-independent methods to examine tetR gene occurrence associated with OTC use in aquaculture. PMID:20217406

  15. [Evaluation of the Epsilometer (Etest) method for the detection of tetracycline susceptibility in Paenibacillus larvae, the causal agent of American foulbrood disease of honeybees].

    PubMed

    Alippi, Adriana M; Reynaldi, Francisco J; López, Ana C

    2013-01-01

    American foulbrood (AFB) is a bacterial disease caused by the spore-forming, grampositive bacterium Paenibacillus larvae, which affects honeybee broods worldwide. The aim of this work was to compare the Epsilometer test (Etest) to the agar dilution method for testing a collection of 22 P. larvae strains to tetracycline by using MYPGP and Iso- Sensitest agars. Results showed that a categorical agreement of 100% was found when using Iso-Sensitest, while a categorical agreement of 86.36% was found (with 3 minor errors) when MYPGP was tested. In conclusion, the Etest could be a rapid and reliable method for testing MIC values of tetracycline in P. larvae only when used in combination with Iso-Sensitest agar. Nevertheless, these results should be confirmed with future studies involving a larger number of isolates. Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  16. In vitro and in vivo tetracycline-controlled myogenic conversion of NIH-3T3 cells: evidence of programmed cell death after muscle cell transplantation.

    PubMed

    Del Bo, R; Torrente, Y; Corti, S; D'Angelo, M G; Comi, G P; Fagiolari, G; Salani, S; Cova, A; Pisati, F; Moggio, M; Ausenda, C; Scarlato, G; Bresolin, N

    2001-01-01

    Ex vivo gene therapy of Duchenne muscular dystrophy based on autologous transplantation of genetically modified myoblasts is limited by their premature senescence. MyoD-converted fibroblasts represent an alternative source of myogenic cells. In this study the forced MyoD-dependent conversion of murine NIH-3T3 fibroblasts into myoblasts under the control of an inducible promoter silent in the presence of tetracycline was evaluated. After tetracycline withdrawal this promoter drives the transcription of MyoD in the engineered fibroblasts, inducing their myogenesis and giving rise to beta-galactosidase-positive cells. MyoD-expressing fibroblasts withdrew from the cell cycle, but were unable to fuse in vitro into multinucleated myotubes. Five days following implantation of engineered fibroblasts in muscles of C57BL/10J mice we observed a sevenfold increase of beta-galactosidase-positive regenerating myofibers in animals not treated with antibiotic compared with treated animals. After 1 week the number of positive fibers decreased and several apoptotic myonuclei were detected. Three weeks following implantation of MyoD-converted fibroblasts in recipient mice, no positive "blue" fiber was observed. Our results suggest that transactivation by tetracycline of MyoD may drive an in vivo myogenic conversion of NIH-3T3 fibroblasts and that, in this experimental setting, apoptosis plays a relevant role in limiting the efficacy of engineered fibroblast transplantation. This work opens the question whether apoptotic phenomena also play a general role as limiting factors of cell-mediated gene therapy of inherited muscle disorders.

  17. A new three-phase heterocrystal catalysts and their superior treatment efficiency for tetracycline

    NASA Astrophysics Data System (ADS)

    Wang, Feng-Rui; Sun, Hui-Ping; Wang, Yan; Liu, Jin-Ku; Fang, Yi; Wang, Jian-Dong

    An easy recyclable and interesting Ag3PO4@Pt@TiO2 (APTP) three-phase heterocrystal chains were self-assembled by the cohesive action and chemical construction of polyvinylpyrrolidone (PVP). We found that a new electron-hole transmission path has been built via the rematch of the band structure of Ag3PO4, Pt and TiO2 which extends the light absorption and promoted the electron-hole separation to treat the antibiotic residues in the water. Based on the thorough investigations, a new catalytic material was provided for antibiotics degradation. The catalytic activity of APTP toward the degradation of tetracycline solution was enhanced by 166.67% and the stability increased remarkably compared with pure Ag3PO4 through the integration of different functional components.

  18. Campylobacter species occurrence within internal organs and tissues of commercial caged Leghorn laying hens.

    PubMed

    Cox, N A; Richardson, L J; Buhr, R J; Fedorka-Cray, P J

    2009-11-01

    Campylobacter spp. are frequently present in the intestinal tract and internal tissues of broiler breeder and broiler chickens. Campylobacter spp. ecology in commercial Leghorn laying hens has not been extensively studied. The objectives of the current study were to determine 1) Campylobacter spp. presence in the reproductive tract, lymphoid organs, liver-gallbladder, and ceca of commercial Leghorn laying hens; 2) species of Campylobacter present; and 3) antimicrobial resistance pattern of Campylobacter isolates. In study 1, three flocks ranging from 94 to 105 wk of age were sampled from a commercial laying complex. In study 2, two flocks, 82 and 84 wk of age, were sampled from a separate complex. Hens were killed, defeathered, aseptically necropsied, and the spleen, liver-gallbladder, ovarian follicles, and upper (infundibulum, magnum, and isthmus) and lower (shell gland and vagina) reproductive tracts were aseptically removed before the ceca. Samples were packed on ice and transported to the laboratory for evaluation. For speciation, a standard BAX real-time PCR method was used while susceptibility testing was performed using US National Antimicrobial Resistance Monitoring System (NARMS) standards and recommended quality control organisms. Isolates were examined for susceptibility using a semi-automated testing system (Sensititer) to the following 9 antimicrobials: azithromycin, clindamycin, ciprofloxacin, erythromycin, florfenicol, gentamicin, nalidixic acid, telithromycin, and tetracycline. In study 1, the isolation rate was 13, 67, 53, 3, 13, and 57% from the ovarian follicles, lower reproductive tract, upper reproductive tract, spleen, liver-gallbladder, and ceca, respectively. In study 2, the isolation rate was 17, 43, 33, 20, 17, and 73% from the ovarian follicles, lower reproductive tract, upper reproductive tract, spleen, liver-gallbladder, and ceca, respectively. Overall, 50% of isolates were Campylobacter jejuni, 49% Campylobacter coli, and 1

  19. Longitudinal Study of the Persistence of Antimicrobial-Resistant Campylobacter Strains in Distinct Swine Production Systems on Farms, at Slaughter, and in the Environment

    PubMed Central

    Quintana-Hayashi, Macarena P.

    2012-01-01

    The objectives of this study were to compare and characterize the prevalence of antimicrobial-resistant (AR) Campylobacter in conventional and antimicrobial-free (ABF) production systems on farms, at slaughter, and in the environment. Fecal and environmental samples were collected from ABF farms (pigs, 1,239; environment, 797) and conventional farms (pigs, 1,650; environment, 1,325). At slaughter, we collected samples from carcasses, including postevisceration swabs, postchill swabs, and mesenteric lymph nodes from ABF systems (postevisceration swabs, 182; postchill swabs, 199; mesenteric lymph nodes, 184) and conventional systems (postevisceration swabs, 272; postchill swabs, 271; mesenteric lymph nodes, 255) at separate processing facilities. We also sampled the processing plant environment, including truck and lairage floor swab samples (ABF, 115; conventional, 90). Overall, a total of 2,908 Campylobacter isolates, including Campylobacter coli (farm, 2,557, 99.8%; slaughter, 341, 98.3%) and Campylobacter jejuni (farm, 4, 0.2%; slaughter, 6, 1.7%), were isolated in the study. There was no significant difference in the prevalence of Campylobacter between ABF and conventionally raised pigs (farrowing, P = 0.20; nursery, P = 0.06; finishing, P = 0.24) and the environment (P = 0.37). At slaughter, Campylobacter was isolated from all of the stages, including postchill. The highest frequencies of resistance were exhibited against tetracycline (ABF, 48.2%; conventional, 88.3%). Ciprofloxacin-resistant C. coli isolates were observed in conventionally raised (17.1%) and ABF (1.2%) pigs (P = 0.11). Antimicrobial use data from conventional farms indicated significant associations between oxytetracycline use and tetracycline resistance in the nursery pigs (P = 0.01), between tiamulin exposure and azithromycin and erythromycin resistance in nursery (P < 0.01) and finishing (P < 0.01) pigs, and between enrofloxacin exposure and ciprofloxacin and nalidixic acid resistance in

  20. Transformation of tetracycline during chloramination: kinetics, products and pathways.

    PubMed

    Wan, Yi; Jia, Ai; Zhu, Zhou; Hu, Jianying

    2013-01-01

    To assess the potential adverse effects stemming from tetracycline (TC) in drinking water or disinfected wastewater, the kinetics of the chloramination of TC was investigated at room temperature, the transformation products and pathways of their generation were elucidated, and their growth inhibiting properties towards sludge bacteria were assessed. The chloramination of TC exhibited pseudo-first-order kinetics with the rate constants (k(obs)) ranging from 0.0082 to 0.041 min(-1) at pH of 6-8. Chloramination of TC generated at least 13 discernible products, and the structures of 12 products, including five chlorinated compounds, were identified using LC-ESI-MS. Two main pathways for the generation of these products were proposed: (1) chlorine substitution reactions followed by dehydration; and (2) oxidization by chloramine. The chlorinated products were proposed to be further degraded to small molecules via the scission of benzene rings of TC, and two oxidization products (2,11a-dihydroxy-keto-TC and 6,11-epoxy-2,11a-dihydroxy-TC) were the final products obtained under the experimental conditions. The chlorinated solution, even without detection of TC, exhibited greater than 80% of TC inhibitory effects towards sludge bacteria, suggesting potential effects on microorganisms in aquatic environment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Pheno- and genotypic analysis of antimicrobial resistance properties of Yersinia ruckeri from fish.

    PubMed

    Huang, Yidan; Michael, Geovana Brenner; Becker, Roswitha; Kaspar, Heike; Mankertz, Joachim; Schwarz, Stefan; Runge, Martin; Steinhagen, Dieter

    2014-07-16

    Enteric red-mouth disease, caused by Yersinia ruckeri, is an important disease in rainbow trout aquaculture. Antimicrobial agents are frequently used in aquaculture, thereby causing a selective pressure on bacteria from aquatic organisms under which they may develop resistance to antimicrobial agents. In this study, the distribution of minimal inhibitory concentrations (MICs) of antimicrobial agents for 83 clinical and non-clinical epidemiologically unrelated Y. ruckeri isolates from north west Germany was determined. Antimicrobial susceptibility was conducted by broth microdilution at 22 ± 2°C for 24, 28 and 48 h. Incubation for 24h at 22 ± 2°C appeared to be suitable for susceptibility testing of Y. ruckeri. In contrast to other antimicrobial agents tested, enrofloxacin and nalidixic acid showed a bimodal distribution of MICs, with one subpopulation showing lower MICs for enrofloxacin (0.008-0.015 μg/mL) and nalidixic acid (0.25-0.5 μg/mL) and another subpopulation exhibiting elevated MICs of 0.06-0.25 and 8-64 μg/mL, respectively. Isolates showing elevated MICs revealed single amino acid substitutions in the quinolone resistance-determining region (QRDR) of the GyrA protein at positions 83 (Ser83-Arg or -Ile) or 87 (Asn87-Tyr), which raised the MIC values 8- to 32-fold for enrofloxacin or 32- to 128-fold for nalidixic acid. An isolate showing elevated MICs for sulfonamides and trimethoprim harbored a ∼ 8.9 kb plasmid, which carried the genes sul2, strB and a dfrA14 gene cassette integrated into the strA gene. These observations showed that Y. ruckeri isolates were able to develop mutations that reduce their susceptibility to (fluoro)quinolones and to acquire plasmid-borne resistance genes. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Effect of a bacteriophage cocktail in combination with modified atmosphere packaging in controlling Listeria monocytogenes on fresh-cut spinach

    USDA-ARS?s Scientific Manuscript database

    A Listeria monocytogenes-specific bacteriophage cocktail (ListShield™) was evaluated for its activity against a nalidixic acid-resistant L. monocytogenes (Lm-NalR) isolate on fresh-cut spinach stored under modified atmosphere packaging (MAP) at various temperatures. Pieces (~2x2 cm2) of fresh spinac...

  3. In vitro susceptibility of Helicobacter pullorum strains to different antimicrobial agents.

    PubMed

    Ceelen, Liesbeth; Decostere, Annemie; Devriese, Luc A; Ducatelle, Richard; Haesebrouck, Freddy

    2005-01-01

    The in vitro activity of 13 antimicrobial agents against 23 Helicobacter pullorum strains from poultry (21) and human (two) origin, and one human H. canadensis strain was tested by the agar dilution method. With the H. pullorum strains, monomodal distributions of Minimum Inhibitory Concentrations (MICs) were seen with lincomycin, doxycycline, gentamicin, tobramycin, erythromycin, tylosin, metronidazole, and enrofloxacin in concentration ranges considered as indicating susceptibility in other bacteria. The normal susceptibility level for nalidixic acid was situated at or slightly above the MIC breakpoints proposed for Campylobacteriaceae. Ampicillin, ceftriaxone, and sulphamethoxazole-trimethoprim showed poor activity against H. pullorum. For the H. canadensis strain, a similar susceptibility pattern was seen, except for nalidixic acid and enrofloxacin, whose MIC of >512 and 8 microg/ml, respectively, indicated resistance of this agent. With spectinomycin, a bimodal distribution of the MICs was noted for the tested strains; eight H. pullorum isolates originating from one flock showed acquired resistance (MIC>512 microg/ml).

  4. Campylobacter Antimicrobial Drug Resistance among Humans, Broiler Chickens, and Pigs, France

    PubMed Central

    Prouzet-Mauléon, Valérie; Kempf, Isabelle; Lehours, Philippe; Labadi, Leila; Camou, Christine; Denis, Martine; de Valk, Henriette; Desenclos, Jean-Claude; Mégraud, Francis

    2007-01-01

    We describe isolates from human Campylobacter infection in the French population and the isolates' antimicrobial drug resistance patterns since 1986 and compare the trends with those of isolates from broiler chickens and pigs from 1999 to 2004. Among 5,685 human Campylobacter isolates, 76.2% were C. jejuni, 17.2% C. coli, and 5.0% C. fetus. Resistance to nalidixic acid increased from 8.2% in 1990 to 26.3% in 2004 (p<10-3), and resistance to ampicillin was high over time. Nalidixic acid resistance was greater for C. coli (21.3%) than for C. jejuni (14.9%, p<10-3). C. jejuni resistance to ciprofloxacin in broilers decreased from 31.7% in 2002 to 9.0% in 2004 (p = 0.02). The patterns of resistance to quinolones and fluoroquinolones were similar between 1999 and 2004 in human and broiler isolates for C. jejuni. These results suggest a potential benefit of a regulation policy limiting use of antimicrobial drugs in food animals. PMID:17479889

  5. Quinolone resistance.

    PubMed

    Brown, J C; Amyes, S G

    1998-01-01

    Quinolone antibacterial agents were first introduced into the clinical environment in the early 1960s. The first qumolone to be clinically used was nalidixic acid, which was used for the treatment of enteric and urinary tract infections. As a result of increased clinical resistance to this drug, its use has declined. However, the development of other chemically related antimicrobials with activities approaching one thousand times that of nalidixic acid has meant that bacteria resistant to this early nonfluormated quinolone are susceptible to the action of the newer fluoroquinolones. The fluoroquinolones, such as ciprofloxacin and ofloxacin, have proved to be potent antimicrobials and are used throughout the world in the treatment of bacterial infections, ranging from urinary tract infections to life-threatening septicemia. The clinical success of these agents can be attributed to their broad spectrum of activity, unique mechanism of action, good tissue distribution, and absorption from the gastrointestinal tract after oral admmistration (1).

  6. Performance of vertical up-flow constructed wetlands on swine wastewater containing tetracyclines and tet genes.

    PubMed

    Huang, Xu; Liu, Chaoxiang; Li, Ke; Su, Jianqiang; Zhu, Gefu; Liu, Lin

    2015-03-01

    Antibiotics and antibiotic resistance genes (ARGs) pollution in animal feeding farms received more public attention recently. Livestock wastewater contains large quantities of antibiotics and ARGs even after traditional lagoon treatment. In this study, the performance of vertical up-flow constructed wetlands (VUF-CWs) on swine wastewater containing tetracycline compounds (TCs) and tet genes was evaluated based on three aspects, TCs and tet genes removal efficiencies, residual TCs and tet genes in soils and plants, and the effect of TCs accumulation on nutrients removal and tet genes development. High removal efficiencies (69.0-99.9%) were achieved for oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) with or without OTC spiked in the influent additionally. TCs concentrations in surface soils increased at first two sampling periods and then decreased after plants were harvested. Satisfactory nutrients removal efficiencies were also obtained, but TN and NH4-N removal efficiencies were significantly negative correlated with total concentration of TCs (∑TCs) in the soils (p < 0.01). The absolute abundances of all the target genes (tetO, tetM, tetW, tetA, tetX and intI1) were greatly reduced with their log units ranging from 0.26 to 3.3. However, the relative abundances of tetO, tetM and tetX in some effluent samples were significantly higher than those in the influent (p < 0.05). The relative abundances of tet genes except for tetO were significantly correlated with ∑TCs in the soils (p < 0.05). In summary, the proposed VUF-CWs are effective alternative for the removal of TCs and tet genes. But it is of great importance to prevent large accumulation of TCs in the soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Characterization of drug resistant Salmonella enterica serotype Typhimurium by antibiograms, plasmids, integrons, resistance genes and PFGE.

    PubMed

    Benacer, Douadi; Thong, Kwai-Lin; Watanabe, Haruo; Puthucheary, Savithri Devi

    2010-06-01

    Forty-seven Salmonella Typhimurium (33 zoonotic, 14 clinical) strains were tested for antimicrobial resistance using the standard disk diffusion method. Presence of relevant resistance genes and class 1 integrons were investigated by using PCR. Pulsed-field gel electrophoresis (PFGE) and plasmid profiling were carried out to determine the genomic diversity of Salmonella Typhimurium. Approximately 57.4% of S. Typhimurium were multidrug resistant (MDR) and showed high resistance rates to tetracycline (70.2%), sulphonamides (57.4%), streptomycin (53.1%), ampicillin (29.7%), nalidixic acid (27.6%), kanamycin (23.4%), chloramphenicol (21.2%) and trimethoprim (19.1%). Resistance towards cephalosporins was noted for cephalothin (27.6%), cephradine (21.2%), amoxicillin clavulanic acid (17.0%) and cephalexin (17.0%). Resistance genes, blaTEM, strA, aadA, sul1, sul2, tet(A), tet(B) and tet(C) were detected among the drug resistant strains. Thirty-three strains (70.2%) carried class 1 integrons, which were grouped in 9 different profiles. DNA sequencing identified sat, aadA, pse-1 and dfrA genes in variable regions on class 1 integrons. Thirty-five strains (74.4%) were subtyped to 22 different plasmid profiles, each with 1 - 6 plasmids (2.0 to 95 kb). PFGE subtyped the 47 strains into 39 profiles. In conclusion, high rates of multidrug-resistance were found among the Malaysian Salmonella Typhimurium strains. The emergence of multidrug-resistant Salmonella Typhimurium to cephalosporin antibiotics was also observed. The strains were very diverse and no persistent clone was observed. The emergence of MDR Salmonella Typhimurium is a worldwide problem and this report provides information for the better understanding of the prevalence and epidemiology of MDR S. Typhimurium in Malaysia.

  8. Role of the RS1 sequence of the cholera vibrio in amplification of the segment of plasmid DNA carrying the gene of resistance to tetracycline and the genes of cholera toxin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fil'kova, S.L.; Il'ina, T.S.; Gintsburg, A.L.

    1988-11-01

    The hybrid plasmid pCO107, representing cointegrate 14(2)-5(2) of two plasmids, an F-derivative (pOX38) and a PBR322-derivative (pCT105) with an RS1 sequence of the cholera vibrio cloned in its makeup, contains two copes of RS1 at the sites of union of the two plasmids. Using a tetracycline resistance marker (Tc/sup R/) of the plasmid pCT105, clones were isolated which have an elevated level of resistance to tetracycline (an increase of from 4- to 30-fold). Using restriction analysis and the Southern blot method of hybridization it was shown that the increase in the level of resistance of tetracycline is associated with themore » amplification of pCT105 portion of the cointegrate, and that the process of amplification is governed by the presence of direct repeats of the RS1 sequence at its ends. The increase in the number of copies of the pCT105 segment, which contains in its composition the genes of cholera toxin (vct), is accompanied by an increase in toxin production.« less

  9. Pancreatic cancer combination therapy using a BH3 mimetic and a synthetic tetracycline

    PubMed Central

    Quinn, Bridget A.; Dash, Rupesh; Sarkar, Siddik; Azab, Belal; Bhoopathi, Praveen; Das, Swadesh K.; Emdad, Luni; Wei, Jun; Pellecchia, Maurizio; Sarkar, Devanand; Fisher, Paul B.

    2015-01-01

    Improved treatments for pancreatic cancer remain a clinical imperative. Sabutoclax, a small molecule BH3 mimetic, inhibits the function of anti-apoptotic Bcl-2 proteins. Minocycline, a synthetic tetracycline, displays antitumor activity. Here we offer evidence of the combinatorial antitumor potency of these agents in several preclinical models of pancreatic cancer. Sabutoclax induced growth arrest and apoptosis in pancreatic cancer cells and synergized with Minocycline to yield a robust mitochondria-mediated caspase-dependent cytotoxicity. This combinatorial property relied upon loss of phosphorylated Stat3 insofar as reintroduction of activated Stat3 rescued cells from toxicity. Tumor growth was inhibited potently in both immune-deficient and immune-competent models with evidence of extended survival. Overall, our results showed that that the combination of Sabutoclax and Minocycline was highly cytotoxic to pancreatic cancer cells and safely efficacious in vivo. PMID:26032425

  10. Generalized canine discoid lupus erythematosus responsive to tetracycline and niacinamide therapy.

    PubMed

    Rossi, Michael A; Messenger, Linda M; Linder, Keith E; Olivry, Thierry

    2015-01-01

    Discoid lupus erythematosus (DLE) is a commonly reported canine autoimmune disease that normally presents with a phenotype consisting of erythema, depigmentation, scaling, erosions/ulcers, and scarring over the nasal planum and the proximal dorsal muzzle. Recently, two cases of a generalized variant of this disease have been reported, whose lesions responded to either systemic glucocorticoids or a combination of topical corticosteroids, topical tacrolimus, and the oral antimalarial hydroxychloroquine. The purpose of this report is to describe an 11 yr old shih tzu that presented with skin lesions consisting of multiple annular, erythematous papules and plaques, hyperpigmentation, adherent scaling, and atrophic scars over the caudal dorsum, flanks, craniodorsal thorax, and lateroproximal extremities. A diagnosis of generalized DLE was made based on the clinical presentation, histopathology, laboratory values, and direct immunofluorescence findings. Treatment consisted of oral tetracycline and oral niacinamide, which resulted in complete remission of clinical signs. This is the first documented report of generalized canine DLE responding to the described immunomodulating regimen. Such a combination might therefore be considered as a glucocorticoid and/or antimalarial alternative for the management of generalized DLE.

  11. The adsorption of tetracycline and vancomycin onto nanodiamond with controlled release.

    PubMed

    Giammarco, James; Mochalin, Vadym N; Haeckel, James; Gogotsi, Yury

    2016-04-15

    The unique properties and tailorable surface of detonation nanodiamonds have given rise to an abundance of potential biomedical applications. Very little is known about the details of adsorption/desorption equilibria of drugs on/from nanodiamonds with different purity, surface chemistry, and agglomeration state. The studies presented here delve into the details of adsorption and desorption of tetracycline (TET) and vancomycin (VAN) on nanodiamond, which are critically important for the rational design of the nanodiamond drug delivery systems. The nanodiamonds studied in these experiments were as-received (ND), purified and carboxyl terminated (ND-COOH), and aminated (ND-NH2). The monolayer capacities of the drugs loaded onto the nanodiamonds are reported herein using Langmuir and Freundlich isotherm models. The results from the desorption studies demonstrate that, by changing the pH environment of drug loaded nanodiamond using buffers of pH 4.09, 7.45, 8.02, and a phosphate buffered saline (PBS) solution, the drug release can effectively be triggered. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Aeromonas hydrophila and Aeromonas veronii Predominate among Potentially Pathogenic Ciprofloxacin- and Tetracycline-Resistant Aeromonas Isolates from Lake Erie

    PubMed Central

    Shinko, Jasmine; Augustyniak, Alexander; Gee, Christopher; Andraso, Greg

    2014-01-01

    Members of the genus Aeromonas are ubiquitous in nature and have increasingly been implicated in numerous diseases of humans and other animal taxa. Although some species of aeromonads are human pathogens, their presence, density, and relative abundance are rarely considered in assessing water quality. The objectives of this study were to identify Aeromonas species within Lake Erie, determine their antibiotic resistance patterns, and assess their potential pathogenicity. Aeromonas strains were isolated from Lake Erie water by use of Aeromonas selective agar with and without tetracycline and ciprofloxacin. All isolates were analyzed for hemolytic ability and cytotoxicity against human epithelial cells and were identified to the species level by using 16S rRNA gene restriction fragment length polymorphisms and phylogenetic analysis based on gyrB gene sequences. A molecular virulence profile was identified for each isolate, using multiplex PCR analysis of six virulence genes. We demonstrated that Aeromonas comprised 16% of all culturable bacteria from Lake Erie. Among 119 Aeromonas isolates, six species were identified, though only two species (Aeromonas hydrophila and A. veronii) predominated among tetracycline- and ciprofloxacin-resistant isolates. Additionally, both of these species demonstrated pathogenic phenotypes in vitro. Virulence gene profiles demonstrated a high prevalence of aerolysin and serine protease genes among A. hydrophila and A. veronii isolates, a genetic profile which corresponded with pathogenic phenotypes. Together, our findings demonstrate increased antibiotic resistance among potentially pathogenic strains of aeromonads, illustrating an emerging potential health concern. PMID:24242249

  13. [Residues of tetracycline and quinolones in wild fish living around a salmon aquaculture center in Chile].

    PubMed

    Fortt Z, Antonia; Cabello C, Felipe; Buschmann R, Alejandro

    2007-02-01

    The presence of residues of tetracycline, quinolones and antiparasitic drugs was investigated in wild fish captured around salmon aquaculture pens in Cochamó, Region X, Chile. Residues of both antibiotics were found in the meta [corrected] of two species of wild fish that are consumed by humans, robalo (Elginops maclovinus) and cabrilla (Sebastes capensis) [corrected] These findings suggest that the antibiotic usage in salmon aquaculture in Chile has nvironmental implications that may affect human and animal health. More studies are needed in Chile to determine the relevance of these findings for human and animal health and the environment to regulate this use of antibiotics.

  14. Incidence and transferability of antibiotic resistance in the enteric bacteria isolated from hospital wastewater

    PubMed Central

    Alam, Mohammad Zubair; Aqil, Farrukh; Ahmad, Iqbal; Ahmad, Shamim

    2013-01-01

    This study reports the occurrence of antibiotic resistance and production of β-lactamases including extended spectrum beta-lactamases (ESβL) in enteric bacteria isolated from hospital wastewater. Among sixty-nine isolates, tested for antibiotic sensitivity, 73.9% strains were resistant to ampicillin followed by nalidixic acid (72.5%), penicillin (63.8%), co-trimoxazole (55.1%), norfloxacin (53.6%), methicillin (52.7%), cefuroxime (39.1%), cefotaxime (23.2%) and cefixime (20.3%). Resistance to streptomycin, chloramphenicol, nitrofurantoin, tetracycline, and doxycycline was recorded in less than 13% of the strains. The minimum inhibitory concentration (MIC) showed a high level of resistance (800–1600 μg/mL) to one or more antibiotics. Sixty three (91%) isolates produced β-lactamases as determined by rapid iodometric test. Multiple antibiotic resistances were noted in both among ESβL and non-ESβL producers. The β-lactamases hydrolyzed multiple substrates including penicillin (78.8% isolates), ampicillin (62.3%), cefodroxil (52.2%), cefotoxime (21.7%) and cefuroxime (18.8%). Fifteen isolates producing ESβLs were found multidrug resistant. Four ESβL producing isolates could transfer their R-plasmid to the recipient strain E. coli K-12 with conjugation frequency ranging from 7.0 × 10−3 to 8.8 × 10−4. The findings indicated that ESβL producing enteric bacteria are common in the waste water. Such isolates may disseminate the multiple antibiotic resistance traits among bacterial community through genetic exchange mechanisms and thus requires immediate attention. PMID:24516448

  15. Prevalence, serovars, phage types, and antibiotic susceptibilities of Salmonella strains isolated from animals in the United Arab Emirates from 1996 to 2009.

    PubMed

    Münch, Sebastian; Braun, Peggy; Wernery, Ulrich; Kinne, Jörg; Pees, Michael; Flieger, Antje; Tietze, Erhard; Rabsch, Wolfgang

    2012-10-01

    The aim of this study was to give some insights into the prevalence, serovars, phage types, and antibiotic resistances of Salmonella from animal origin in the United Arab Emirates. Data on diagnostic samples from animals (n = 20,871) examined for Salmonella between 1996 and 2009 were extracted from the databases of the Central Veterinary Research Laboratory in Dubai and from typed strains (n = 1052) from the Robert Koch Institute, Wernigerode Branch in Germany and analyzed for general and animal-specific trends. Salmonella was isolated from 1,928 (9 %) of the 20,871 samples examined. Among the 1,052 typed strains, most were from camels (n = 232), falcons (n = 166), bustards (n = 101), antelopes (n = 66), and horses (n = 63). The predominant serovars were Salmonella Typhimurium (25 %), Salmonella Kentucky (8 %), followed by Salmonella Frintrop (7 %), and Salmonella Hindmarsh (5 %). When analyzed by animal species, the most frequent serovars in camels were Salmonella Frintrop (28 %) and Salmonella Hindmarsh (21 %), in falcons Salmonella Typhimurium (32 %), in bustards Salmonella Kentucky (19 %), in antelopes Salmonella Typhimurium (9 %), and in horses Salmonella Typhimurium (17 %) and S. Kentucky (16 %). Resistance of all typed Salmonella strains (n = 1052) was most often seen to tetracycline (23 %), streptomycin (22 %), nalidixic acid (18 %), and ampicillin (15 %). These data show trends in the epidemiology of Salmonella in different animal species which can be used as a base for future prevention, control, and therapy strategies.

  16. Use of whole-genome sequencing for Campylobacter surveillance from NARMS retail poultry in the United States in 2015.

    PubMed

    Whitehouse, Chris A; Young, Shenia; Li, Cong; Hsu, Chih-Hao; Martin, Gordon; Zhao, Shaohua

    2018-08-01

    Whole genome sequencing (WGS) has become a rapid and affordable tool for public health surveillance and outbreak detection. In this study, we used the Illuminia MiSeq ® to sequence 589 Campylobacter isolates obtained in 2015 from retail poultry meats as part of the National Antimicrobial Resistance Monitoring System (NARMS). WGS data were used to identify the Campylobacter species and to compare the concordance between resistance genotypes and phenotypes. WGS accurately identified 386 C. jejuni and 203 C. coli using gyrA sequence information. Ten resistance genes, including tetO, bla OXA-61 , aph(2″)-Ic, aph(2″)-If, aph(2″)-Ig, aph(3')-III, ant(6)-1a, aadE, aph(3")-VIIa, and Inu(C), plus mutations in housekeeping genes (gyrA at position 86, 23S rRNA at position 2074 and 2075), were identified by WGS analysis. Overall, there was a high concordance between phenotypic resistance to a given drug and the presence of known resistance genes. Concordance between both resistance and susceptible phenotypes and genotype was 100% for ciprofloxacin, nalidixic acid, gentamicin, azithromycin, and florfenicol. A few discrepancies were observed for tetracycline, clindamycin, and telithromycin. The concordance between resistance phenotype and genotype ranged from 67.9% to 100%; whereas, the concordance between susceptible phenotype and genotype ranged from 98.0% to 99.6%. Our study demonstrates that WGS can correctly identify Campylobacter species and predict antimicrobial resistance with a high degree of accuracy. Published by Elsevier Ltd.

  17. Effects of Menthol Supplementation in Feedlot Cattle Diets on the Fecal Prevalence of Antimicrobial-Resistant Escherichia coli

    PubMed Central

    Aperce, C. C.; Amachawadi, R.; Van Bibber-Krueger, C. L.; Nagaraja, T. G.; Scott, H. M.; Vinasco-Torre, J.; Drouillard, J. S.

    2016-01-01

    The pool of antimicrobial resistance determinants in the environment and in the gut flora of cattle is a serious public health concern. In addition to being a source of human exposure, these bacteria can transfer antibiotic resistance determinants to pathogenic bacteria and endanger the future of antimicrobial therapy. The occurrence of antimicrobial resistance genes on mobile genetic elements, such as plasmids, facilitates spread of resistance. Recent work has shown in vitro anti-plasmid activity of menthol, a plant-based compound with the potential to be used as a feed additive to beneficially alter ruminal fermentation. The present study aimed to determine if menthol supplementation in diets of feedlot cattle decreases the prevalence of multidrug-resistant bacteria in feces. Menthol was included in diets of steers at 0.3% of diet dry matter. Fecal samples were collected weekly for 4 weeks and analyzed for total coliforms counts, antimicrobial susceptibilities, and the prevalence of tet genes in E. coli isolates. Results revealed no effect of menthol supplementation on total coliforms counts or prevalence of E. coli resistant to amoxicillin, ampicillin, azithromycin, cefoxitin, ceftiofur, ceftriaxone, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfisoxazole, and sulfamethoxazole; however, 30 days of menthol addition to steer diets increased the prevalence of tetracycline-resistant E. coli (P < 0.02). Although the mechanism by which menthol exerts its effects remains unclear, results of our study suggest that menthol may have an impact on antimicrobial resistance in gut bacteria. PMID:28030622

  18. The incidence of antibiotic resistance and other characteristics amongst Escherichia coli strains causing fatal infection in chickens: the utilization of these characteristics to study the epidemiology of the infection

    PubMed Central

    Heller, E. D.; Smith, H. Williams

    1973-01-01

    Of 173 epidemiologically unrelated strains of Escherichia coli isolated from the pericardial sac of chickens that had died from infection with these organisms in England in 1972, approximately 1 year after the introduction of legislation forbidding the routine use of feeds containing `therapeutic' antibiotics, 83·8% were resistant to sulphonamides, 31·2% to tetracyclines, 20·8% to furazolidone, 18·5% to streptomycin, 2·9% to spectinomycin and 1·2% to ampicillin; none of the strains were resistant to chloramphenicol, neomycin, polymixin, trimethoprim or nalidixic acid. The sulphonamide resistance and possibly some of the resistance to other agents might have been the consequence of sulphonamides being exempted from the legislation. Much of the resistance, with the exception of that to furazolidone, was of the transferable type. Many strains possessed transfer factors in the absence of any known transferable characteristic. Colicine production was twice as common in the pathogenic strains as in a collection of strains isolated from the faeces of healthy chickens; about half of it was transferable. By means of serology, antibiotic resistance and other markers, it was found that several different kinds of E. coli were usually incriminated in any one outbreak of E. coli infection in broiler chickens. Sometimes the same kinds of E. coli were found in outbreaks in consecutive crops of chickens on the same farm. New kinds, too, appeared to be brought in by replacement chickens. PMID:4272208

  19. Species diversity and antibiotic resistance properties of Staphylococcus of farm animal origin in Nkonkobe Municipality, South Africa.

    PubMed

    Adegoke, Anthony A; Okoh, Anthony I

    2014-03-01

    The occurrence and antibiotic susceptibility profile of Staphylococcus isolates of healthy farm animal origin in Nkonkobe Municipality as well as the prevalence of putative antibiotic resistance genes were investigated using phenotypic and molecular methods. A total of 120 Staphylococcus isolates were isolated from 150 animal samples and consisted of Staphylococcus haemolyticus (30 %) and Staphylococcus aureus (23.3 %) from pig, Staphylococcus capitis (15 %) from goat, S. haemolyticus (5 %) and Staphylococcus xylosus (15 %) from cattle, and other staphylococci (11.7 %) from dead chicken and pigs. Besides this, the presence of these isolates was observed from the animal dung, showing that the organisms are shed to the environment. About 23.3 % of these isolates were coagulase-positive and 76.7 % were coagulase-negative Staphylococcus. Between 75 and 100 % of the isolates were resistant to penicillin G, tetracycline, sulfamethoxazole, and nalidixic acid; about 38 % were methicillin-resistant staphylococci, including 12.6 % methicillin-resistant S. aureus from pigs. In total, 12 % of all isolates were vancomycin resistant. Also, 12 % of the isolates were erythromycin resistant, while 40.2 % were resistant to ceftazidime. Only the genes mecA and mphC could be confirmed, whereas the genes vanA, vanB, ermA, ermB, and ermC could not be detected. The high phenotypic antibiotic resistance and the presence of some associated resistance genes is a potential threat to public health and suggest the animals to be important reservoirs of antibiotic resistance determinants in the environment.

  20. Antimicrobial resistance in Escherichia coli isolates from food animals, animal food products and companion animals in China.

    PubMed

    Lei, Tao; Tian, Wei; He, Liu; Huang, Xian-Hui; Sun, Yong-Xue; Deng, Yu-Ting; Sun, Yan; Lv, Dian-Hong; Wu, Cong-Ming; Huang, Liang-Zong; Shen, Jian-Zhong; Liu, Jian-Hua

    2010-11-20

    One thousand and thirty Escherichia coli isolates from food animals, animals-derived foods, and companion animals between 2007 and 2008 in Southern China were used to investigate their antimicrobial susceptibility to 14 different antimicrobials by the standard agar dilution method. More than 70% of isolates showed resistance to tetracycline, trimethoprim-sulphamethoxazole, nalidixic acid, and ampicillin. In general, resistance was less frequent in companion animal isolates vs food animals isolates, but cephalosporin and amikacin resistance was more frequent in companion animal isolates, 42.6% to 56.2% vs 14.1% to 24.3%, and 28.5% vs 18.8%, respectively, which was most likely due to the common use of these antimicrobials as treatment in pet animals. Fluoroquinolones resistance was high in all animal isolates (>50%). Food products showed lowest resistance among isolates from these three resources. PFGE analysis indicated that a majority of multidrug-resistant E. coli isolates showed unique, unrelated PFGE profiles and were unlikely to be the spread of a specific clone. This study provides useful information about the prevalence of antimicrobial resistance in E. coli isolated from animals and food products in China and provided evidence of the linkage of the use of antimicrobials in animals and its selection of antimicrobial resistance in bacterial isolates. The data from this study further warns the prudent use of antimicrobials in food and pet animals to reduce the risks of transmission of antimicrobial resistance zoonotic pathogen to humans. Copyright © 2010 Elsevier B.V. All rights reserved.